JP7095224B2 - A prepreg for a coreless substrate, a method and an apparatus for manufacturing a prepreg for a coreless substrate, and a coreless substrate and a manufacturing method thereof. - Google Patents

Description

The present invention relates to a prepreg for a coreless substrate, a method and an apparatus for manufacturing a prepreg for a coreless substrate, and a coreless substrate and a method for manufacturing the same.

FRP (Fiber Reinforced Plastics) is a composite material whose strength is improved by using a material with high elasticity such as fiber as an aggregate and putting the aggregate in a base material (matrix) such as plastic. Is. FRP is an inexpensive, lightweight and durable composite material that takes advantage of weather resistance, heat resistance, chemical resistance and light weight, and is particularly used as a prepreg for printed wiring boards by taking advantage of its insulation. ing.

Due to the miniaturization and higher performance of electronic devices in recent years, printed wiring boards are required to have higher wiring densities and higher integrations than ever before, as well as thinner substrates.
As a package structure based on these requirements, for example, Patent Document 1 and Patent Document 2 propose a coreless substrate mainly composed of a build-up layer capable of high-density wiring without having a core substrate. .. This coreless substrate is a substrate composed of only a build-up layer, which is obtained by forming a build-up layer on a support (core substrate) such as a metal plate and then removing the support (core substrate). Become.

Since the rigidity of the coreless substrate is reduced due to the thinning by removing the support (core substrate), the problem that the semiconductor package warps when the semiconductor element is mounted and packaged becomes more remarkable. Warpage is considered to be one of the factors that cause poor connection between a semiconductor element and a printed wiring board, and in a coreless substrate, even more effective reduction of warpage is desired.

Many of the traditional printed wiring board prepregs are manufactured by the Hand Lay-up method. The hand lay-up method is a method in which a varnish in which a resin is dissolved is applied to an aggregate using a coating machine or the like, and then dried and thermally cured (Patent Document 3).

Japanese Unexamined Patent Publication No. 2005-72085 Japanese Unexamined Patent Publication No. 2002-26171 Japanese Unexamined Patent Publication No. 01-272416

With the thinning of the substrate, a fiber base material having a thinner thickness than the conventional one is being used as an aggregate. Since such a thin fiber base material has weak mechanical strength, when the varnish is applied, dried, etc. by the hand lay-up method, its own weight exceeds the load capacity of the fiber base material and the fiber base material is cut. was there. Further, when the gap of the coater is narrowed in order to adjust the amount of resin applied to the fiber base material, there is a problem that the workability is inferior, such as tearing.
Further, in order to achieve both high accuracy of the thickness after lamination and resin filling property (moldability) in the inner layer circuit pattern, the amount of resin adhered to the aggregate differs by several mass%, and the thermosetting resin is used. It is complicated because a plurality of types of prepregs must be manufactured from one type of aggregate, such as those having different curing times and those combining them. Further, since the coating conditions are changed for each production, the loss of the material used for production is large.
Furthermore, the conventional prepreg has a large variation in thickness when the wiring board is formed, and the dimensional change generated by the thermal history when soldering the wiring board and the semiconductor device is also large, which is caused by these. Warpage occurred, and the level of warpage reduction required for coreless substrates was not achieved.

The subject of the present invention is a method and apparatus for manufacturing a prepreg for a coreless substrate, which has good workability and can obtain a prepreg for a coreless substrate having excellent thickness accuracy and dimensional stability, and a coreless substrate obtained by the manufacturing method. It is an object of the present invention to provide a prepreg, a coreless substrate using the prepreg for a coreless substrate, and a method for manufacturing the same.

As a result of elite research, the present inventors have achieved good workability and productivity by a manufacturing method in which a resin film containing a thermosetting resin composition is pressed against an aggregate under normal pressure, which is excellent in workability. We have found that a prepreg having excellent dimensional stability can be obtained, and have reached the present invention. That is, the present invention relates to the following [1] to [15].
[1] A method for producing a prepreg for a coreless substrate, wherein a resin film (I) containing a thermosetting resin composition is attached to at least one surface of a sheet-shaped aggregate.
A method for producing a prepreg for a coreless substrate, wherein the pasting is performed by a film pressure welding step in which the resin film (I) is pressure-welded to at least one surface of the sheet-shaped aggregate under normal pressure.
[2] The method for producing a prepreg for a coreless substrate according to the above [1], wherein the film pressure welding step is a step of pressing the resin film (I) against both surfaces of the sheet-shaped aggregate.
[3] The film pressure welding step heats the resin film (I) in the range of -40 ° C to + 20 ° C, which is the minimum melt viscosity temperature of the resin film (I), and at least the sheet-like aggregate. The method for manufacturing a prepreg for a coreless substrate according to the above [1] or [2], which is a step of pressure-welding to one surface.
[4] The resin film (I) has a maleimide compound (a) having at least two N-substituted maleimide groups in one molecule, and an amine compound (b) having at least two primary amino groups in one molecule. ), And the method for producing a coreless substrate prepreg according to any one of the above [1] to [3], which comprises a thermosetting resin composition containing a thermoplastic elastomer (c).
[5] The resin film (I) has a maleimide compound (a) having at least two N-substituted maleimide groups in one molecule and an amine compound having at least two primary amino groups in one molecule (5). B), a thermosetting resin composition containing a modified polyimide (X) which is a reaction product of the above [1] to [3]. The method for manufacturing a prepreg for a coreless substrate according to any one.
[6] The method for producing a prepreg for a coreless substrate according to the above [4] or [5], wherein the thermosetting resin composition further contains a thermosetting resin (d).
[7] A coreless substrate prepreg manufacturing apparatus used in the method for manufacturing a coreless substrate prepreg according to any one of the above [1] to [6].
A device for manufacturing a prepreg for a coreless substrate, which has a film pressure contacting means for pressing and attaching the resin film (I) to at least one of the sheet-shaped aggregates under normal pressure.
[8] A coreless substrate prepreg manufactured by the method for manufacturing a coreless substrate prepreg according to any one of the above [1] to [6].
[9] The dimensional change rate (i) after etching measured according to the following measuring method is −8.0 to +8.0%, and the dimensional change rate (ii) after heating at 170 ° C. for 1 hour is -4. The prepreg for a coreless substrate according to the above [8], which is 0.0 to + 4.0%.
<Measurement method of dimensional change rate>
A 250 cm square copper-clad laminate having 12 μm-thick electrolytic copper foils on both surfaces of the prepreg is used as an evaluation substrate, and a total of four reference holes are provided adjacent to each other in a portion 1 cm vertically and 1 cm horizontally from the four corners. Using the average value of the distance between holes as the standard dimension,
After removing the copper foil by immersing the evaluation board in a copper etching solution, the average value of the distances between adjacent holes is defined as the post-etching dimension.
The evaluation substrate after etching is calculated based on the following formula with the average value of the distances between adjacent holes after heating at 170 ° C. for 1 hour as the dimension after heating.
Dimensional change rate (i) (%) = (post-etching dimension-standard dimension) x 100 / standard dimension Dimensional change rate (ii) (%) = (post-heating dimension-post-etching dimension) x 100 / post-etching dimension [10 ] The coreless substrate prepreg according to the above [8] or [9], wherein the value of the thickness accuracy measured according to the following measuring method is 10% or less.
<Measurement method of thickness accuracy>
A total of 11 points in the width direction in 50 mm increments from the center of the copper-clad laminate having electrolytic copper foils with a thickness of 12 μm on both surfaces of the prepreg, and 10 points in 50 mm increments in the length direction starting from the 11 points. The maximum thickness, the minimum thickness and the average thickness are measured, and the rate of change of the maximum thickness with respect to the average thickness and the rate of change of the minimum thickness with respect to the average thickness are calculated based on the following formula. Each is obtained, and the larger value is used as the thickness accuracy value.
Maximum thickness change rate (%) = (maximum thickness-average thickness) x 100 / average thickness Minimum thickness change rate (%) = (average thickness-minimum thickness) x 100 / average thickness [11] The prepreg for a coreless substrate according to any one of the above [8] to [10], wherein the elastic modulus of the cured product is 10 to 20 GPa.
[12] The prepreg for a coreless substrate according to any one of the above [8] to [11], wherein the cured product has a coefficient of thermal expansion of 5.0 to 6.5 ppm / ° C.
[13] A coreless substrate containing an insulating layer formed by using the prepreg for a coreless substrate according to any one of the above [8] to [12].
[14] A semiconductor package in which a semiconductor element is mounted on the coreless substrate according to the above [13].
[15] A method for manufacturing a coreless substrate, in which a build-up layer formed by alternately laminating conductor layers and insulating layers is formed on a support, and then the build-up layer is separated from the support. A method for manufacturing a coreless substrate, wherein at least one layer of the insulating layer is formed by using the prepreg for a coreless substrate manufactured by the method for manufacturing a prepreg for a coreless substrate according to the above [1] to [6].

According to the present invention, a method and an apparatus for manufacturing a prepreg for a coreless substrate, which has good workability and can obtain a prepreg for a coreless substrate having excellent thickness accuracy and dimensional stability, and a prepreg for a coreless substrate obtained by the manufacturing method. , And a coreless substrate using the prepreg for a coreless substrate and a method for manufacturing the same can be provided.

It is a conceptual diagram of the manufacturing method of the prepreg of this invention, and the manufacturing apparatus of a prepreg. It is a schematic diagram which shows one aspect of the manufacturing method of the coreless substrate of this invention.

[Manufacturing method and manufacturing equipment of prepreg for coreless substrate]
The method for producing a prepreg for a coreless substrate (hereinafter, also simply referred to as “prepreg”) of the present invention is a method for producing a thermosetting resin composition on at least one surface of a sheet-like aggregate (hereinafter, also simply referred to as “aggregate”). A method for manufacturing a prepreg for a coreless substrate to which a resin film (I) (hereinafter, also simply referred to as “resin film (I)”) containing the above-mentioned resin film (I) is attached. ) Is a method for manufacturing a prepreg for a coreless substrate, which is carried out by a film pressure welding step of pressure-welding to at least one surface of the sheet-shaped aggregate.
The coreless substrate prepreg manufacturing apparatus of the present invention is a coreless substrate prepreg manufacturing apparatus used in the method for manufacturing a coreless substrate prepreg of the present invention, and the resin film (I) is formed under normal pressure. It is a prepreg manufacturing apparatus for a coreless substrate, which has a film pressure contacting means for pressing and attaching to at least one of the sheet-shaped aggregates.
Here, "pasting" means a state in which the thermosetting resin composition of the resin film (I) is in contact with the aggregate, and the thermosetting resin composition of the resin film (I) is contained in the aggregate. The latter state is particularly preferable, including the state of entering the gap.
The film pressure welding step may be a step of pressing the resin film (I) against one surface of the sheet-shaped aggregate, or may be a step of pressing the resin film (I) against both surfaces of the sheet-shaped aggregate. However, from the viewpoint of productivity, it is preferable to perform a step of pressure-welding to both surfaces of the sheet-shaped aggregate.

Hereinafter, a preferred embodiment of the prepreg manufacturing method and the prepreg manufacturing apparatus 1 of the present invention will be specifically described with reference to FIG. 1.
The prepreg manufacturing apparatus 1 will be described as an apparatus in which a pair of resin films (I) 54 are melt-bonded to both sides of the sheet-shaped aggregate 40, respectively, but one resin film (I) 54 is described as a sheet-shaped bone. It may be a device to be attached only to one surface of the material 40. In this case, in FIG. 1, one of the resin film delivery device 3, the protective film peeling mechanism 4, and the protective film winding device 5, which is below (or above) the aggregate 40, is unnecessary.

The method for manufacturing a prepreg of the present invention can be performed by the prepreg manufacturing apparatus 1.
The prepreg manufacturing apparatus 1 is placed under normal pressure from the viewpoint of workability. Here, in the present specification, "under normal pressure" is synonymous with "under atmospheric pressure". When the prepreg is manufactured by this method, for example, there is a tendency that the problem of workability that tends to occur when a vacuum laminator or the like is adopted does not occur, and excellent workability can be obtained.

The prepreg manufacturing device 1 includes an aggregate delivery device 2, a pair of resin film delivery devices 3 and 3, a sheet heating and pressurizing device (film pressure contacting means) 6, and a prepreg winding device 8. It is preferable that the prepreg manufacturing apparatus 1 further includes a sheet pressure cooling device 7, a pair of protective film peeling mechanisms 4 and 4, and a pair of protective film winding devices 5 and 5.

The aggregate delivery device 2 is a device that rotates a roll on which a sheet-shaped aggregate 40 is wound in a direction opposite to the winding direction to deliver the aggregate 40 wound on the roll. In FIG. 1, the aggregate delivery device 2 sends the aggregate 40 from the lower side of the roller toward the sheet heating / pressurizing device 6.

The pair of resin film delivery devices 3 and 3 can rotate the roll on which the resin film (I) 50 with a protective film is wound and the roll while applying a predetermined tension to the resin film (I) 50 with a protective film to be sent out. The resin film (I) 50 with a protective film wound around the roll is rotated in the direction opposite to the winding direction, and the resin film (I) 50 with a protective film is wound around the roll. It is a device that sends out. As will be described later, the resin film (I) 50 with a protective film is the surface of the resin film (I) 54 and one of the aggregate side films of the resin film (I) 54 (of both surfaces of the resin film (I) 54). , The surface on the aggregate 40 side) is a sheet-like film including a protective film 52 laminated on 54a.
In the resin film (I) 50 with a protective film, a support is usually attached to the surface of the resin film (I) opposite to the surface to which the protective film 52 is attached. That is, it has a structure of a support / resin film (I) / protective film. When the resin film (I) has one or more composed of a group consisting of a support and a protective film, the layer formed by forming the thermosetting resin composition is referred to as a "resin layer". Sometimes referred to.

The pair of resin film delivery devices 3 and 3 are located on the front surface 40a side and the back surface 40b side of the delivered aggregate 40, respectively.
One resin film delivery device 3 is located on the surface 40a side of the sent aggregate 40, and the protective film 52 is on the side of the sent aggregate 40, so that the resin film (I) with one protective film (I) It is a device that feeds 50 from the lower side of the roller toward one of the protective film peeling mechanisms 4.
Similarly, the other resin film delivery device 3 is located on the back surface 40b side of the fed aggregate 40, and the protective film 52 is on the side of the fed aggregate 40, so that the resin film with the other protective film is provided. (I) A device that feeds 50 from the upper side of the roller toward the other protective film peeling mechanism 4.

The pair of protective film peeling mechanisms 4 and 4 are turning rollers located on the front surface 40a side and the back surface 40b side of the delivered aggregate 40, respectively.
One protective film peeling mechanism 4 receives the resin film (I) 50 with a protective film, which is sent out from the one resin film delivery device 3 and advances toward the one protective film peeling mechanism 4, on the surface of the rotating turning roller. The resin film (I) 54 of one of the resin films (I) 50 with a protective film is advanced toward the sheet heating and pressurizing device 6, and the one protective film 52 is moved toward the one protective film winding device 5. This is a mechanism for peeling one protective film 52 from one of the resin films (I) 50 with a protective film by advancing toward. As a result, the aggregate side film surface 54a of one of the resin films (I) 54 is exposed.
Similarly, the other protective film peeling mechanism 4 is a turning roller that rotates the resin film (I) 50 with the other protective film, which is sent out from the other resin film delivery device 3 and advances toward the other protective film peeling mechanism 4. The other resin film (I) 54 of the other resin film (I) 50 with a protective film is advanced toward the sheet heating and pressurizing device 6, and the other protective film 52 is moved toward the other protective film. It is a mechanism for peeling the other protective film 52 from the other protective film-attached resin film (I) 50 by advancing toward the winding device 5. As a result, the aggregate side film surface 54a of the other resin film (I) 54 is exposed.

The pair of protective film winding devices 5 and 5 are located on the front surface 40a side and the back surface 40b side of the sent aggregate 40, respectively, and are peeled off by the pair of protective film peeling mechanisms 4 and 4, the protective film 52 and It is a winding device that winds up 52.

The sheet heating / pressurizing device 6 has a pair of heating / compression rollers and a compression force applying mechanism (not shown) that applies a compressive force to the pair of heating / compression rollers. The pair of heat compression rollers have a heating body inside so that they can be heated at a predetermined set temperature.
The sheet heating and pressurizing device 6 presses the resin films (I) 54 and 54 against the inserted aggregate 40 with a pair of rotating heating and compression rollers to form a sheet-shaped prepreg 60 (film pressure welding step), and also prepares the prepreg. 60 is sent out toward the sheet pressure cooling device 7. Specifically, the resin films (I) 54 and 54 delivered from the pair of protective film peeling mechanisms 4 and 4, respectively, are laminated on the front surface 40a and the back surface 40b of the aggregate 40 delivered from the aggregate delivery device 2. The aggregate 40 delivered from the aggregate delivery device 2 and the resin films (I) 54 and 54 delivered from the pair of protective film peeling mechanisms 4 and 4, respectively, are placed between the pair of heat compression rollers. Get in.
At this time, one resin film (I) 54 is laminated on the aggregate 40 so that the aggregate side film surface 54a side of one resin film (I) 54 adheres to the surface 40a side of the aggregate 40, and also. The other resin film (I) 54 is laminated on the aggregate 40 to form the prepreg 60 so that the aggregate side film surface 54a side of the other resin film (I) 54 adheres to the back surface 40b side of the aggregate 40. To. The prepreg 60 sent out from the sheet heating / pressurizing device 6 is in a high temperature state.

The sheet pressure cooling device 7 has a pair of cooling compression rollers and a compression force applying mechanism (not shown) for applying a compressive force to the pair of cooling compression rollers. The pair of cooling compression rollers compresses and cools the high-temperature prepreg 60, which is sent out from the sheet heating and pressurizing device 6, by the pair of rotating cooling compression rollers, and sends the prepreg winding device 8 to the prepreg winding device 8.

The prepreg winding device 8 has a roll for winding the sheet-shaped prepreg 60 sent out from the sheet pressure cooling device 7, and a drive mechanism (not shown) for rotating the roll.
After laminating the rollers, it is preferable to cool them with a cooling compression roller to remove unnecessary heat and flatten the product.

The above-mentioned prepreg manufacturing apparatus 1 operates as follows.
First, the sheet-shaped aggregate 40 is sent out from the aggregate delivery device 2 toward the sheet heating / pressurizing device 6. At this time, the front surface 40a and the back surface 40b of the aggregate 40 are exposed.

On the other hand, the protective film peeling mechanism of one of the resin films (I) 50 with a protective film is removed from the lower side of the roller of one of the resin film delivery devices 3 so that the protective film 52 is on the side of the sent aggregate 40. It is being sent out toward 4. Further, the other protective film peeling mechanism 4 is used to remove the other protective film-attached resin film (I) 50 from the upper side of the roller of the other resin film delivery device 3 so that the protective film 52 is on the side of the sent aggregate 40. Is being sent out toward.

Next, the one of the resin films (I) 50 with a protective film sent out is hung on the turning roller which is the one protective film peeling mechanism 4, and when the resin film (I) 50 is turned, the aggregate side film surface 54a is exposed. The one protective film 52 is peeled off from the one protective film-attached resin film (I) 50, and the one resin film (I) 54 is advanced toward the sheet heating / pressurizing device 6. As a result, the aggregate side film surface 54a of one of the resin films (I) 54 is exposed. Similarly, the other protective film-attached resin film (I) 50 that has been sent out is hung on the turning roller, which is the other protective film peeling mechanism 4, so that the aggregate side film surface 54a is exposed when the resin film (I) 50 is turned. The other protective film 52 is peeled off from the other protective film-attached resin film (I) 50, and the other resin film (I) 54 is advanced toward the sheet heating / pressurizing device 6. As a result, the aggregate side film surface 54a of the other resin film (I) 54 is exposed.
The pair of protective films 52 and 52 that have been peeled off are wound by the pair of protective film winding devices 5 and 5, respectively.

The aggregates are sent out so that the resin films (I) 54 and 54, which are sent out from the aggregate delivery device 2 and have the front surface 40a and the back surface 40b laminated on the aggregate 40, respectively, from which the aggregate side film surfaces 54a and 54a are melted. The aggregate 40 sent out from the device 2 and the resin films (I) 54 and 54 sent out from the pair of protective film peeling mechanisms 4 and 4, respectively, enter between the pair of heat compression rollers 6. Further, under normal pressure, the aggregate side film surfaces 54a and 54a of the pair of resin films (I) 54 and 54 are pressed against the aggregate 40 with the front surface 40a and the back surface 40b, respectively, by the sheet heating and pressurizing device 6. A prepreg 60 is obtained (film pressure welding step). At this time, by controlling the temperature of the heating body inside the pair of heating and compressing rollers, the pair of heating and compressing rollers are maintained at a predetermined temperature, and pressure is applied while heating during the film pressure welding step.

When the resin film (I) is heat-pressed and adhered to the aggregate, the temperature of the heat compression roller is minus the minimum melt viscosity temperature measured by a leometer of the thermosetting resin composition used for forming the resin film (I). The range from 40 ° C to plus 20 ° C is preferable. That is, in the film pressure welding step, the resin film (I) is heated to a range of -40 ° C to + 20 ° C, which is the minimum melt viscosity temperature of the resin film (I), and is applied to at least one surface of the sheet-shaped aggregate. The step of pressure welding is preferable.
The minimum melt viscosity temperature of the thermosetting resin composition is preferably 60 to 150 ° C., more preferably 80 to 140 ° C., and even more preferably 100 to 130 ° C. from the viewpoint of prepreg productivity.

The prepreg 60 sent out from the sheet heating / pressurizing device 6 is further pressurized and cooled by the sheet pressurizing / cooling device 7.
The prepreg 60 sent out from the sheet pressure cooling device 7 is wound by the prepreg winding device 8.

Next, the sheet-shaped aggregate and the resin film (I) used in the method for producing a prepreg of the present invention will be described in order.

<Sheet-like aggregate>
Examples of the sheet-like aggregate include woven fabrics and non-woven fabrics in which an inorganic fiber base material, an organic fiber base material, or the like is used alone or in combination.
Examples of the inorganic fiber base material include glass such as E glass, D glass, S glass and Q glass, and a fiber base material such as carbon, and examples of the organic fiber base material include polyimide, polyester, tetrafluoroethylene, aramid and cell roll. And the like, and the fiber base material can be mentioned.
As the aggregate, those having a shape such as woven fabric, non-woven fabric, robink, chopped strand mat, and surfaced mat can be used. Among these, woven fabric or non-woven fabric is preferable.
The material and shape of the aggregate are appropriately selected depending on the intended use, performance, etc. of the molded product, and may be a fiber base material consisting of one type of material and one type of shape, or two or more types, if necessary. It may be an aggregate made of the above materials, or it may be an aggregate having two or more kinds of shapes.
The thickness of the aggregate is, for example, 0.002 to 0.5 mm, preferably 4 to 100 μm, more preferably 6 to 50 μm, and 8 to 8 to 3 from the viewpoint of making the substrate thinner and enabling high-density wiring. 20 μm is more preferable, and 8 to 15 μm is particularly preferable.
From the viewpoint of heat resistance, moisture resistance, processability, etc., the aggregate is preferably surface-treated with a silane coupling agent or the like, or mechanically opened.

<Resin film (I)>
The resin film (I) is a resin film containing a thermosetting resin composition.
The resin film (I) is preferably in the state of a "resin film with a support (I)" in which a support is attached to one surface of the resin film (I), and further, the other of the resin film (I). It may be in the state of "a support and a resin film (I) with a protective film" having a protective film on the surface of the surface.

The thermosetting resin composition comprising the resin film (I) has a maleimide having at least two N-substituted maleimide groups in one molecule from the viewpoints of heat resistance, low thermal expansion property, dielectric property and dimensional stability. Compound (a) (hereinafter, also referred to as "component (a)" or "maleimide compound (a)"), an amine compound (b) having at least two primary amino groups in one molecule (hereinafter, "(b)" ) Ingredients ”or“ amine compound (b) ”) is preferably contained.
Further, from the same viewpoint, the thermosetting resin composition contains a maleimide compound (a) having at least two N-substituted maleimide groups in one molecule and at least two primary amino groups in one molecule. It is preferable to contain the modified polyimide (X) which is a reaction product of the amine compound (b) having.
Hereinafter, each component constituting the thermosetting resin composition will be described.

(Maleimide compound (a) having at least two N-substituted maleimide groups in one molecule)
The maleimide compound (a) is not particularly limited as long as it is a maleimide compound having at least two N-substituted maleimide groups in one molecule. The maleimide compound (a) may be used alone or in combination of two or more.
As the maleimide compound (a), a maleimide compound having two N-substituted maleimide groups in one molecule is preferable, and a compound represented by the following general formula (a-1) is more preferable.

（一般式（ａ－１）中、Ｘ^ａ１は、下記一般式（ａ１－１）、（ａ１－２）、（ａ１－３）又は（ａ１－４）で表される基である。）

(In the general formula (a-1), ^Xa1 is a group represented by the following general formulas (a1-1), (a1-2), (a1-3) or (a1-4)).

（一般式（ａ１－１）中、Ｒ^ａ１は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。ｐは０～４の整数である。）

(In the general formula (a1-1), R ^a1 is an aliphatic hydrocarbon group or a halogen atom having 1 to 5 carbon atoms independently. P is an integer of 0 to 4).

（一般式（ａ１－２）中、Ｒ^ａ２及びＲ^ａ３は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。Ｘ^ａ２は炭素数１～５のアルキレン基、炭素数２～５のアルキリデン基、エーテル基、スルフィド基、スルホニル基、カルボニルオキシ基、ケト基、単結合又は下記一般式（ａ１－２－１）で表される基である。ｑ及びｒは各々独立に０～４の整数である。）

(In the general formula (a1-2), Ra ^{2 and Ra 3 are independently aliphatic hydrocarbon groups or halogen atoms having 1 to 5 carbon atoms. X a2 is an} alkylene group having 1 to 5 carbon atoms and carbon. The numbers 2 to 5 are an alkylidene group, an ether group, a sulfide group, a sulfonyl group, a carbonyloxy group, a keto group, a single bond, or a group represented by the following general formula (a1-2-1). Q and r are each. It is an independently integer from 0 to 4.)

（一般式（ａ１－２－１）中、Ｒ^ａ４及びＲ^ａ５は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。Ｘ^ａ３は炭素数１～５のアルキレン基、炭素数２～５のアルキリデン基、エーテル基、スルフィド基、スルホニル基、カルボニルオキシ基［－Ｏ－Ｃ（＝Ｏ）－］、ケト基又は単結合である。ｓ及びｔは各々独立に０～４の整数である。）

(In the general formula ( ^a1-2-1 ), Ra4 and ^Ra5 are independently aliphatic hydrocarbon groups or halogen atoms having 1 to 5 carbon atoms. X ^a3 is an alkylene group having 1 to 5 carbon atoms. , Alkylidene group with 2 to 5 carbon atoms, ether group, sulfide group, sulfonyl group, carbonyloxy group [-OC (= O)-], keto group or single bond. S and t are 0 independently. It is an integer of ~ 4.

（一般式（ａ１－３）中、ｎは１～１０の整数である。）

(In the general formula (a1-3), n is an integer of 1 to 10.)

（一般式（ａ１－４）中、Ｒ^ａ６及びＲ^ａ７は各々独立に、水素原子又は炭素数１～５の脂肪族炭化水素基である。ｕは１～８の整数である。）

(In the general formula (a1-4), ^Ra6 and ^Ra7 are independently hydrogen atoms or aliphatic hydrocarbon groups having 1 to 5 carbon atoms. U is an integer of 1 to 8.)

In the general formula (a1-1), the aliphatic hydrocarbon group represented by ^Ra1 includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group and n. -Centyl group and the like can be mentioned. The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, and more preferably a methyl group. Further, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.
Among the above, an aliphatic hydrocarbon group having 1 to 5 carbon atoms is preferable as ^Ra1 .
p is an integer of 0 to 4, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0, from the viewpoint of availability. When p is an integer of 2 or more, the plurality of ^Ra1s may be the same or different.

In the general formula (a1-2), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by ^Ra2 and ^Ra3 and the halogen atom are the same as in the case of ^Ra1 . The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, more preferably a methyl group and an ethyl group, and further preferably an ethyl group.
Examples of the alkylene group having 1 to 5 carbon atoms represented by ^Xa2 include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group and the like. Be done. The alkylene group is preferably an alkylene group having 1 to 3 carbon atoms, and more preferably a methylene group, from the viewpoint of heat resistance and low thermal expansion.
Examples of the alkylidene group having 2 to 5 carbon atoms represented by ^Xa2 include an ethylidene group, a propyridene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group and an isopentylidene group. Among these, an isopropylidene group is preferable from the viewpoint of heat resistance and low thermal expansion.
Among the above options, X ^a2 is preferably an alkylene group having 1 to 5 carbon atoms and an alkylidene group having 2 to 5 carbon atoms. More preferable ones are as described above.
q and r are each independently an integer of 0 to 4, and from the viewpoint of availability, both are preferably an integer of 0 to 2, more preferably 0 or 2. When q or r is an integer of 2 or more, the plurality of Ra ^2s or Ra ^3s may be the same or different from each other.

In the general formula ( ^a1-2-1 ), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by ^Ra4 and Ra5 and the halogen atom are the same as those in the case of ^Ra2 and ^Ra3 . , The preferred ones are the same.
The alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^a3 are the same as the alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^a2 . The same is true for those mentioned and preferred.
Among the above options, X ^a3 is preferably an alkylidene group having 2 to 5 carbon atoms, and more preferable one is as described above.
s and t are integers of 0 to 4, and from the viewpoint of availability, both are preferably integers of 0 to 2, more preferably 0 or 1, and even more preferably 0. When s or t is an integer of 2 or more, the plurality of Ra ^4s or Ra ^5s may be the same or different from each other.
The general formula (a1-2-1) is preferably represented by the following general formula (a1-2-1').

（一般式（ａ１－２－１’）中のＸ^ａ３、Ｒ^ａ４、Ｒ^ａ５、ｓ及びｔは、一般式（ａ１－２－１）中のものと同じであり、好ましいものも同じである。）

(X ^a3 , R ^a4 , R ^a5 , s and t in the general formula (a1-2-1') are the same as those in the general formula (a1-2-1), and the preferred ones are also the same. .)

The group represented by the general formula (a1-2) is preferably a group represented by the following general formula (a1-2'), and any one of the following (a1-i) to (a1-iii). The group represented by (a1-i) or (a1-iii) below is more preferable, and the group represented by (a1-iii) is further preferable.

（一般式（ａ１－２’）中のＸ^ａ２、Ｒ^ａ２、Ｒ^ａ３、ｑ及びｒは、一般式（ａ１－２）中のものと同じであり、好ましいものも同じである。）

(X ^a2 , R ^a2 , R ^a3 , q and r in the general formula (a1-2') are the same as those in the general formula (a1-2'), and the preferred ones are also the same.)

In the general formula (a1-3), n is an integer of 1 to 10, preferably an integer of 1 to 5, and more preferably an integer of 1 to 3 from the viewpoint of availability.
In the general formula (a1-4), the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by ^Ra6 and ^Ra7 and the halogen atom are the same as in the case of R ^a1 in the general formula (a1-1). The same is true for the preferred ones. u is an integer of 1 to 8, preferably an integer of 1 to 3, and more preferably 1.

In the general formula (a-1), ^Xa1 is any of the groups represented by the general formula (a1-1), (a1-2), (a1-3) or (a1-4). Of these, the group represented by (a1-2) is preferable from the viewpoint of low warpage, dimensional stability, heat resistance and availability.

Specific examples of the maleimide compound (a) include bis (4-maleimidephenyl) methane, polyphenylmethane maleimide, bis (4-maleimidephenyl) ether, bis (4-maleimidephenyl) sulfone, 3,3'-dimethyl-. 5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, m-phenylenebismaleimide, 2,2-bis [4- (4-maleimidephenoxy) phenyl] Examples include propane.
Among these, bis (4-maleimidephenyl) methane, bis (4-maleimidephenyl) sulfone, 3,3'-dimethyl-5,5'-diethyl from the viewpoint of high reactivity and higher heat resistance. -4,4'-Diphenylmethane bismaleimide, 2,2-bis [4- (4-maleimide phenoxy) phenyl] propane is preferable, and 3,3'-dimethyl-5,5'from the viewpoint of solubility in a solvent. -Diethyl-4,4'-diphenylmethane Bismaleimide, bis (4-maleimidephenyl) methane is more preferable, and bis (4-maleimidephenyl) methane is further preferable from the viewpoint of production cost.

When the thermosetting resin composition contains the maleimide compound (a), the content thereof is in the thermosetting resin composition from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. 20 to 90 parts by mass is preferable, 30 to 85 parts by mass is more preferable, and 40 to 80 parts by mass is further preferable with respect to 100 parts by mass of the solid content of the resin component.
Here, the solid content in the present embodiment means a component in the thermosetting resin composition other than a volatile substance such as water and a solvent described later. That is, the solid content includes liquid, starch syrup-like or wax-like substances at room temperature around 25 ° C., and does not necessarily mean that it is solid.
The solid content of the resin component in the thermosetting resin composition is, for example, that the thermosetting resin composition has a maleimide compound (a), an amine compound (b), a thermoplastic elastomer (c) described later, and a thermosetting compound described later. When it contains one or more selected from the group consisting of the sex resin (d), it corresponds to the total amount thereof. The curing accelerator (e) described later is not included in the resin component.

(Amine compound (b) having at least two primary amino groups in one molecule)
The amine compound (b) is not particularly limited as long as it is an amine compound having at least two primary amino groups in one molecule. The amine compound (b) may be used alone or in combination of two or more.
As the amine compound (b), an amine compound having two primary amino groups in one molecule is preferable, and a diamine compound represented by the following general formula (b-1) is more preferable.

（一般式（ｂ－１）中、Ｘ^ｂ１は、下記一般式（ｂ１－１）又は（ｂ１－２）で表される基である。）

(In the general formula (b-1), X ^b1 is a group represented by the following general formula (b1-1) or (b1-2).)

（一般式（ｂ１－１）中、Ｒ^ｂ１は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。ｐは０～４の整数である。）

(In the general formula (b1-1), R ^b1 is an aliphatic hydrocarbon group or a halogen atom having 1 to 5 carbon atoms independently. P is an integer of 0 to 4).

（一般式（ｂ１－２）中、Ｒ^ｂ２及びＲ^ｂ３は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。Ｘ^ｂ２は炭素数１～５のアルキレン基、炭素数２～５のアルキリデン基、エーテル基、スルフィド基、スルホニル基、カルボオキシ基、ケト基、単結合又は下記一般式（ｂ１－２－１）で表される基である。ｑ及びｒは各々独立に０～４の整数である。）

(In the general formula (b1-2), R ^b2 and R ^b3 are independently aliphatic hydrocarbon groups or halogen atoms having 1 to 5 carbon atoms. X ^b2 is an alkylene group having 1 to 5 carbon atoms and carbon. The number 2 to 5 is an alkylidene group, an ether group, a sulfide group, a sulfonyl group, a carbooxy group, a keto group, a single bond or a group represented by the following general formula (b1-2-1). Q and r are independent of each other. Is an integer from 0 to 4.)

（一般式（ｂ１－２－１）中、Ｒ^ｂ４及びＲ^ｂ５は各々独立に、炭素数１～５の脂肪族炭化水素基又はハロゲン原子である。Ｘ^ｂ３は炭素数１～５のアルキレン基、炭素数２～５のアルキリデン基、エーテル基、スルフィド基、スルホニル基、カルボオキシ基、ケト基又は単結合である。ｓ及びｔは各々独立に０～４の整数である。）

(In the general formula (b1-2-1), R ^b4 and R ^b5 are independently aliphatic hydrocarbon groups or halogen atoms having 1 to 5 carbon atoms. X ^b3 is an alkylene group having 1 to 5 carbon atoms. , Alkylidene group, ether group, sulfide group, sulfonyl group, carbooxy group, keto group or single bond having 2 to 5 carbon atoms. S and t are independently integers of 0 to 4).

In the general formula (b1-1), the aliphatic hydrocarbon group represented by R ^b1 includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group and n. -Centyl group and the like can be mentioned. The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, and more preferably a methyl group. Further, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.
Among the above, an aliphatic hydrocarbon group having 1 to 5 carbon atoms is preferable as R ^b1 .
p is an integer of 0 to 4, preferably an integer of 0 to 2, and more preferably 2 from the viewpoint of availability. When p is an integer of 2 or more, the plurality of R ^b1s may be the same or different.

In the general formula (b1-2), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ^b2 and R ^b3 and the halogen atom are the same as in the case of R ^b1 . The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, more preferably a methyl group and an ethyl group, and further preferably an ethyl group.
Examples of the alkylene group having 1 to 5 carbon atoms represented by X ^b2 include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group and the like. Be done. The alkylene group is preferably an alkylene group having 1 to 3 carbon atoms, and more preferably a methylene group, from the viewpoint of heat resistance and low thermal expansion.
Examples of the alkylidene group having 2 to 5 carbon atoms represented by X ^b2 include an ethylidene group, a propyridene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group and an isopentylidene group. Among these, an isopropylidene group is preferable from the viewpoint of heat resistance and low thermal expansion.
Among the above options, as X ^b2 , an alkylene group having 1 to 5 carbon atoms and an alkylidene group having 2 to 5 carbon atoms are preferable. More preferable ones are as described above.
q and r are each independently an integer of 0 to 4, and from the viewpoint of availability, both are preferably an integer of 0 to 2, more preferably 0 or 2. When q or r is an integer of 2 or more, the plurality of R ^b2s or R ^b3s may be the same or different from each other.

In the general formula (b1-2-1), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ^b4 and R ^b5 and the halogen atom include the same as in the case of R ^b2 and R ^b3 . , The preferred ones are the same.
The alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^b3 are the same as the alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^b2 . The same is true for those mentioned and preferred.
Among the above options, X ^b3 is preferably an alkylidene group having 2 to 5 carbon atoms, and more preferable one is as described above.
s and t are integers of 0 to 4, and from the viewpoint of availability, both are preferably integers of 0 to 2, more preferably 0 or 1, and even more preferably 0. When s or t is an integer of 2 or more, the plurality of R ^b4s or R ^b5s may be the same or different from each other.
The general formula (b1-2-1) is preferably represented by the following general formula (b1-2-1').

（一般式（ｂ１－２－１’）中のＸ^ｂ３、Ｒ^ｂ４、Ｒ^ｂ５、ｓ及びｔは、一般式（ｂ１－２－１）中のものと同じであり、好ましいものも同じである。）

(X ^b3 , R ^b4 , R ^b5 , s and t in the general formula (b1-2-1') are the same as those in the general formula (b1-2-1), and the preferred ones are also the same. .)

The group represented by the general formula (b1-2) is preferably a group represented by the following general formula (b1-2'), and any of the following formulas (b1-i) to (b1-iii). The group represented by (b1-ii) is more preferable, and the group represented by (b1-ii) is further preferable.

（一般式（ｂ１－２’）中のＸ^ｂ２、Ｒ^ｂ２、Ｒ^ｂ３、ｑ及びｒは、一般式（ｂ１－２）中のものと同じであり、好ましいものも同じである。）

(X ^b2 , R ^b2 , R ^b3 , q and r in the general formula (b1-2') are the same as those in the general formula (b1-2'), and the preferred ones are also the same.)

Examples of the amine compound (b) include diaminobenzidine, diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenylsulfone, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl. , 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl-6,6'-disulfonic acid, 2,2', 5,5'-tetra Chloro-4,4'-diaminobiphenyl, 4,4'-methylene-bis (2-chloroaniline), 1,3'-bis (4-aminophenoxy) benzene, 2,2'-bis [4- (4) -Aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2'-Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,4'-bis (4-aminophenoxy) benzene, 4,4'-diaminodiphenyl sulfide, 2,2'-dimethyl Examples thereof include -4,4'-diaminobiphenyl, 4,4'-diamino-3,3'-biphenyldiol, 9,9'-bis (4-aminophenyl) fluorene, o-tridin sulfone and the like.

Further, the amine compound (b) is preferably a siloxane compound having at least two primary amino groups in one molecule from the viewpoint of low thermal expansion and elasticity, and two primary amino groups in one molecule. A siloxane compound having an amino group is more preferable, and a siloxane compound having a primary amino group at both ends is further preferable.
As the amine compound (b), an amine compound having two primary amino groups in one molecule is preferable, and a diamine compound represented by the following general formula (b-1) is more preferable.

（式中、Ｒ^ｂ６及びＲ^ｂ７は、各々独立に、アルキル基、フェニル基又は置換フェニル基を示し、ｍは、１～１００の整数を示す。）

（式中、Ｒ^ｂ６、Ｒ^ｂ７、Ｒ^ｂ８及びＲ^ｂ９は、各々独立に、アルキル基、フェニル基又は置換フェニル基を示し、Ｘ^ｂ４及びＸ^ｂ５は、各々独立に、２価の有機基を示す。ｍ’は１～１００の整数を示す。）

(In the formula, R ^b6 and R ^b7 each independently represent an alkyl group, a phenyl group or a substituted phenyl group, and m represents an integer of 1 to 100.)

(In the formula, R ^b6 , R ^b7 , R ^b8 and R ^b9 each independently represent an alkyl group, a phenyl group or a substituted phenyl group, and X ^b4 and X ^b5 each independently have a divalent organic group. Indicates. M'indicates an integer from 1 to 100.)

In the general formulas (b-2) and (b-3), the alkyl groups represented by R ^b6 , R ^b7 , R ^b8 and R ^b9 include methyl group, ethyl group, n-propyl group, isopropyl group and n-. Examples thereof include a butyl group, an isobutyl group, a t-butyl group, an n-pentyl group and the like. As the alkyl group, an alkyl group having 1 to 5 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is further preferable.
Examples of the substituent having the phenyl group in the substituted phenyl group include an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, and an alkynyl group having 2 to 5 carbon atoms. Examples of the alkyl group having 1 to 5 carbon atoms include the same as those described above. Examples of the alkenyl group having 2 to 5 carbon atoms include a vinyl group and an allyl group. Examples of the alkynyl group having 2 to 5 carbon atoms include an ethynyl group and a propargyl group.
R ^b6 , R ^b7 , R ^b8 and R ^b9 are all preferably alkyl groups having 1 to 5 carbon atoms, and more preferably methyl groups.
m and m'are an integer of 1 to 100 from the viewpoint of low thermal expansion, and an integer of 5 to 50 is preferable from the viewpoint of compatibility and high elasticity. An integer of 10 to 40 is more preferred.
In the general formula (b-3), the divalent organic group represented by X ^b4 and X ^b5 is an alkylene group, an alkenylene group, an alkynylene group, an arylene group, —O— or a divalent linkage thereof. The group etc. can be mentioned. Examples of the alkylene group include an alkylene group having 1 to 10 carbon atoms such as a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group and a 1,5-pentamethylene group. Be done. Examples of the alkenylene group include an alkenylene group having 2 to 10 carbon atoms. Examples of the alkynylene group include an alkynylene group having 2 to 10 carbon atoms. Examples of the arylene group include an arylene group having 6 to 20 carbon atoms such as a phenylene group and a naphthylene group. Among these, the divalent organic group represented by X ^b4 and X ^b5 is preferably an alkylene group, more preferably a 1,3-trimethylene group.

As the amine compound (b), a commercially available product can be used. Commercially available products of the amine compound (b) include, for example, "PAM-E" (functional group equivalent 130 of amino group) and "KF-8010" (functional group of amino group) which are siloxane compounds having amino groups at both ends. Equivalent 430), "X-22-161A" (amino group functional group equivalent 800), "X-22-161B" (amino group functional group equivalent 1,500), "KF-8012" (amino group functionality) Base equivalent 2,200), "KF-8008" (amino group functional group equivalent 5,700) [above, manufactured by Shin-Etsu Chemical Industry Co., Ltd.], "BY16-871" (amino group functional group equivalent 130), " BY16-853U ”(functional group equivalent of amino group 460) [above, manufactured by Tohredo Corning Co., Ltd.] and the like (the unit of functional group equivalent of amino group is g / mol).

When the thermosetting resin composition contains the amine compound (b), the content thereof is in the thermosetting resin composition from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. 5 to 50 parts by mass is preferable, 10 to 40 parts by mass is more preferable, and 12 to 30 parts by mass is further preferable with respect to 100 parts by mass of the solid content of the resin component.

(Modified polyimide (X))
The modified polyimide (X) is obtained by reacting the component (a) and the component (b), and has a structural unit (a') derived from the component (a) and a structural unit (b) derived from the component (b). b') and is contained.
The modified polyimide (X) may be used alone or in combination of two or more.
There is no particular limitation on the reaction method between the component (a) and the component (b). The reaction temperature is preferably 70 to 200 ° C., more preferably 100 to 130 ° C. from the viewpoint of productivity and sufficient progress of the reaction. The reaction time is preferably 0.5 to 10 hours, more preferably 1 to 6 hours.

The reaction between the component (a) and the component (b) is preferably carried out in an organic solvent. Examples of the organic solvent include alcohol solvents such as ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; acetate, γ-butyrolactone, and the like. Ester-based solvent; Ether-based solvent such as tetrahydrofuran; Fragrant solvent such as toluene, xylene, mesitylen, etc .; Nitrogen atom-containing solvent such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone; Sulfur atom-containing solvent such as dimethylsulfoxide, etc. Can be mentioned.
Among these, cyclohexanone, propylene glycol monomethyl ether, methyl cellosolve, and γ-butyrolactone are preferable from the viewpoint of solubility, and cyclohexanone and propylene glycol are preferable from the viewpoint of low toxicity and high volatility and difficult to remain as a residual solvent. Monomethyl ether and dimethylacetamide are preferable, and propylene glycol monomethyl ether is more preferable.

The ratio [(a) / (b)] of the equivalent of the maleimide group derived from the component (a) to the equivalent of the primary amino group derived from the component (b) in the reaction is the prevention of gelation and heat resistance. From the viewpoint, it is preferably more than 1, more preferably 5 to 35, still more preferably 12 to 30.

The content of the structural unit (a') in the modified polyimide (X) is preferably 30 to 95% by mass, preferably 40 to 90%, from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. The mass% is more preferable, and 60 to 85% by mass is further preferable.
The content of the structural unit (b') in the modified polyimide (X) is preferably 5 to 70% by mass, preferably 10 to 60% by mass, from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. The mass% is more preferable, and 15 to 40% by mass is further preferable.
The preferable contents of the structural unit (a') and the structural unit (b') in the thermosetting resin composition are based on 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. , Each of which is the same as the preferred embodiment of the contents of the component (a) and the component (b) in the thermosetting resin composition.
However, when the thermosetting resin composition further contains one or more selected from the group consisting of the component (a) and the component (b) in addition to the modified polyimide (X), each component and each component are derived. It is preferable that the total content with the structural unit is a suitable embodiment of the content of the component (a) and the component (b) in the thermosetting resin composition described above.

When the thermosetting resin composition contains the modified polyimide (X), the content thereof is in the thermosetting resin composition from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. With respect to 100 parts by mass of the solid content of the resin component, 40 to 100 parts by mass is preferable, 50 to 95 parts by mass is more preferable, and 60 to 92 parts by mass is further preferable.

(Thermoplastic elastomer (c))
The thermosetting resin composition preferably further contains the thermoplastic elastomer (c). That is, the resin film (I) comprises a thermosetting resin composition containing the component (a), the component (b) and the thermoplastic elastomer (c), or the component (a) and the component (b). It is preferable that it contains a thermosetting resin composition containing a modified polyimide (X) which is a reaction product of the above and a thermoplastic elastomer (c).
The thermoplastic elastomer (c) may be used alone or in combination of two or more.
Examples of the thermoplastic elastomer (c) include styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, acrylic-based thermoplastic elastomers, and silicone-based thermoplastic elastomers. , Derivatives of these elastomers and the like. These usually consist of a hard segment component and a soft segment component, and the former generally contributes to heat resistance and strength, and the latter contributes to flexibility and toughness.
Among these, from the viewpoint of heat resistance and insulation reliability, a styrene-based thermoplastic elastomer is preferable, and the elasticity of the thermosetting resin composition can be reduced while maintaining good adhesion to the copper foil. From the viewpoint, acrylic thermoplastic elastomers are preferable.

Styrene-based thermoplastic elastomers are polymers formed of molecules containing at least structural units derived from styrene. Examples of the structural unit other than the styrene-derived structural unit of the styrene-based thermoplastic elastomer include a butadiene-derived structural unit, an isoprene-derived structural unit, a maleic acid-derived structural unit, and a maleic anhydride-derived structural unit. These may be contained alone or in two or more kinds.
The structural unit derived from butadiene and the structural unit derived from isoprene are preferably hydrogenated. When hydrogenated, the structural unit derived from butadiene is a structural unit in which ethylene units and butylene units are mixed, and the structural unit derived from isoprene is a structural unit in which ethylene units and propylene units are mixed.

Styrene-based thermoplastic elastomers include styrene-butadiene-styrene block copolymer hydrogenated products, styrene-isoprene-styrene, from the viewpoints of low thermal expansion, adhesive strength with metal circuits, heat resistance, elastic coefficient, and high frequency characteristics. The hydrogenated product of the block copolymer is preferable, and the hydrogenated product of the styrene-butadiene-styrene block copolymer is more preferable.
The hydrogenated additives of the styrene-butadiene-styrene block copolymer include SEBS in which the hydrogenation rate of the carbon-carbon double bond is usually 90% or more (preferably 95% or more), and 1 in the butadiene block. , 2-The carbon-carbon double bond at the bond site is partially hydrogenated SBBS (the hydrogenation rate to the total carbon-carbon double bond is about 60 to 85%). Among these, SEBS is more preferable.

Acrylic thermoplastic elastomers are polymers formed of molecules containing at least structural units derived from acrylic acid esters. The structural unit derived from the acrylic acid ester means a structural unit formed when the acrylic acid ester monomer is polymerized.
The acrylic thermoplastic elastomer contains a repeating structural unit derived from a plurality of different acrylic acid esters in the molecule, and further comprises a repeating structural unit derived from one or more kinds of monomers other than the acrylic acid ester. It may be included. Alternatively, the acrylic thermoplastic elastomer may consist of repeating structural units derived from a plurality of different types of acrylic acid esters in the molecule.

Acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, t-butyl acrylate, pentyl acrylate, hexyl acrylate, cyclohexyl acrylate, acrylic acid. Examples thereof include octyl, decyl acrylate, lauryl acrylate, and benzyl acrylate.
Examples of the monomer other than the acrylic acid ester include vinyl-based monomers such as acrylonitrile, acrylamide, acrylic acid, methacrylic acid, methacrylic acid ester, styrene, ethylene, propylene, and butadiene.

The weight average molecular weight (Mw) of the acrylic thermoplastic elastomer is preferably 1,000 to 200,000, more preferably 2,000 to 150,000. When the weight average molecular weight (Mw) is at least the lower limit value, low elasticity is excellent, and when it is at least the upper limit value, compatibility and fluidity are excellent.
The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC) and converted by a calibration curve prepared using standard polystyrene.

The thermoplastic elastomer (c) may have a reactive functional group at at least one of the molecular terminal and the molecular chain. Examples of the reactive functional group include an epoxy group, a hydroxyl group, a carboxy group, an amino group, an amide group, an isocyanato group, an acrylic group, a (meth) acrylic group, a vinyl group and the like. By having a reactive functional group, the compatibility with other resin components is improved, and the internal stress generated during curing of the thermosetting resin composition can be more effectively reduced, and as a result, the coreless substrate can be obtained. It is possible to remarkably reduce the warp of the. In particular, from the viewpoint of low thermal expansion and adhesive strength with a metal circuit, it is preferable to have at least one selected from the group consisting of an epoxy group, a hydroxyl group, a carboxy group, an amino group and an amide group, and it is preferable to have heat resistance and insulation reliability. From the viewpoint of sex, it is more preferable to have at least one selected from the group consisting of an epoxy group, a hydroxyl group and a carboxy group.

When the thermosetting resin composition contains the thermoplastic elastomer (c), the content thereof improves the compatibility with other resin components, and effectively makes the cured product have low curing shrinkage and low thermal expansion. From the viewpoint of expression, 1 to 60 parts by mass is preferable, 2 to 50 parts by mass is more preferable, and 4 to 25 parts by mass is further preferable with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. ..

(Thermosetting resin (d))
The thermosetting resin composition preferably further contains the thermosetting resin (d). However, the thermosetting resin (d) does not contain the component (a) and the component (b).
Examples of the thermosetting resin (d) include an epoxy resin, a phenol resin, an unsaturated imide resin (however, the component (b) is not included), a cyanate resin, an isocyanate resin, a benzoxazine resin, an oxetane resin, and an amino resin (however). , The above (a) component is not included), unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone resin, triazine resin, melamine resin and the like. Among these, one or more selected from the group consisting of epoxy resin and cyanate resin is preferable, and epoxy resin is more preferable, from the viewpoint of moldability and electrical insulation, and from the viewpoint of adhesive strength with a metal circuit.
The thermosetting resin (d) may be used alone or in combination of two or more.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin and other bisphenol type epoxy resins; phenol novolac type epoxy resin, cresol novolac type epoxy resin, α-naphthol / cresol novolac type epoxy resin. , Novolak type epoxy resin such as bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin, aralkyl novolak type epoxy resin; stillben type epoxy resin, triazine skeleton containing epoxy resin, fluorene skeleton containing epoxy resin, triphenol methane type epoxy resin , Biphenyl type epoxy resin, xylylene type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, polyfunctional phenols and polycyclic aromatic diglycidyl ether compounds such as anthracene. Examples thereof include a phosphorus-containing epoxy resin into which a phosphorus compound has been introduced. Among these, aralkyl novolac type epoxy resin and α-naphthol / cresol novolac type epoxy resin are preferable from the viewpoint of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. As the aralkyl novolac type epoxy resin, an aralkyl novolac type epoxy resin having a biphenyl skeleton is preferable.

When the thermosetting resin composition contains the thermosetting resin (d), the content thereof is the thermosetting resin composition from the viewpoints of low warpage, dimensional stability, thickness accuracy, low thermal expansion and low elasticity. With respect to 100 parts by mass of the solid content of the resin component in the product, 1 to 45 parts by mass is preferable, 2 to 40 parts by mass is more preferable, and 3 to 35 parts by mass is further preferable.

(Curing accelerator (e))
The thermosetting resin composition preferably further contains a curing accelerator (e).
Examples of the curing accelerator (e) include organic metal salts such as zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonatocobalt (III); imidazoles. And derivatives thereof; organic phosphorus compounds; secondary amines; tertiary amines; quaternary ammonium salts and the like. Among these, imidazoles and derivatives thereof are preferable from the viewpoint of heat resistance, flame retardancy and adhesive strength with a metal circuit, and organic phosphorus compounds are preferable from the viewpoint of low thermal expansion.
The curing accelerator (e) may be used alone or in combination of two or more.
When the thermosetting resin composition contains the curing accelerator (e), the content thereof is 0.1 to 10 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. Is preferable, 0.3 to 5 parts by mass is more preferable, and 0.7 to 1.5 parts by mass is further preferable. When the content of the curing accelerator (e) is 0.1 part by mass or more, heat resistance, flame retardancy and copper foil adhesiveness tend to be excellent, and when it is 10 parts by mass or less, heat resistance and aging It tends to be excellent in stability and press formability.

(Inorganic filler (f))
The thermosetting resin composition preferably further contains an inorganic filler (f).
Examples of the inorganic filler (f) include silica, alumina, talc, mica, kaolin, aluminum hydroxide, boehmite, magnesium hydroxide, zinc borate, zinc tinate, zinc oxide, titanium oxide, boron nitride, calcium carbonate, and sulfuric acid. Preferable examples include barium, aluminum borate, potassium titanate, glass powder, and hollow glass beads. Examples of the glass powder include E glass, T glass, D glass and the like.
The inorganic filler (f) may be used alone or in combination of two or more.
Among these, silica is preferable from the viewpoint of dielectric properties, heat resistance and low thermal expansion. Examples of silica include precipitated silica manufactured by a wet method and having a high water content, and dry silica manufactured by a dry method and containing almost no bound water or the like. Dry silica is further classified into crushed silica, fumed silica, molten spherical silica and the like depending on the manufacturing method. Among these, fused spherical silica is preferable from the viewpoint of low thermal expansion and fluidity when filled in the resin.

The average particle size of the inorganic filler (f) is preferably 0.1 to 10 μm, more preferably 0.3 to 8 μm, and even more preferably 0.3 to 3 μm. When the average particle size is 0.1 μm or more, the fluidity when highly filled in the resin tends to be maintained well, and when it is 10 μm or less, the mixing probability of coarse particles is reduced and defects caused by coarse particles are caused. There is a tendency to suppress the occurrence. Here, the average particle size is the particle size of a point corresponding to a volume of 50% when the cumulative frequency distribution curve by the particle size is obtained with the total volume of the particles as 100%, and the laser diffraction scattering method is used. It can be measured with the particle size distribution measuring device or the like.
The inorganic filler (f) may be surface-treated with a coupling agent. The method of surface treatment with a coupling agent may be a method of surface-treating the inorganic filler (f) before compounding by a dry method or a wet method, and the surface-untreated inorganic filler (f) may be used by another method. A so-called inorganic blend treatment method may be used in which a silane coupling agent is added to the composition after blending with the components to form a composition.
Examples of the coupling agent include a silane-based coupling agent, a titanate-based coupling agent, a silicone oligomer and the like.

When the thermosetting resin composition contains the inorganic filler (f), the content thereof is 100 parts by mass of the solid content of the resin component in the thermosetting resin composition from the viewpoint of moldability and low thermal expansion. On the other hand, 20 to 300 parts by mass is preferable, 50 to 200 parts by mass is more preferable, and 70 to 200 parts by mass is further preferable.

(Other ingredients)
Even if the thermosetting resin composition contains a flame retardant, an ultraviolet absorber, an antioxidant, a photopolymerization initiator, a fluorescent whitening agent, an adhesiveness improving agent, etc., as long as the effect of the present invention is not impaired. good.

Flame retardants include halogen-containing flame retardants containing bromine, chlorine, etc .; triphenyl phosphate, tricresyl phosphazene, trisdichloropropyl phosphate, phosphoric acid ester compounds, phosphorus flame retardants such as red phosphorus; guanidine sulfamate. , Nitrogen flame retardants such as melamine sulfate, melamine polyphosphate, melamine cyanurate; phosphazene flame retardants such as cyclophosphazene and polyphosphazene; inorganic flame retardants such as antimony trioxide.

Examples of the ultraviolet absorber include benzotriazole-based ultraviolet absorbers.
Examples of the antioxidant include a hindered phenol-based antioxidant, a hindered amine-based antioxidant, and the like.
Examples of the photopolymerization initiator include benzophenones, benzyl ketals, thioxanthone-based photopolymerization initiators, and the like.
Examples of the fluorescent whitening agent include a fluorescent whitening agent of a stilbene derivative.
Examples of the adhesiveness improving agent include urea compounds such as ureasilane, and coupling agents such as silane-based, titanate-based, and aluminate-based.

The thermosetting resin composition may be in the state of a varnish in which an organic solvent is used as a diluting solvent and each component is dissolved or dispersed in the organic solvent so that it can be easily used in the production of the resin film (I).
Examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; alcohol solvents such as methyl cellosolve; ether solvents such as tetrahydrofuran; aromatic solvents such as toluene, xylene and mesitylen. .. The organic solvent may be used alone or in combination of two or more.
The solid content concentration of the varnish is preferably 40 to 90% by mass, more preferably 50 to 80% by mass. When the solid content concentration of the varnish is within the above range, the coatability is kept good, and the thickness of the resin film (I) and the like can be easily adjusted to an appropriate range.

(Manufacturing method of resin film (I))
The resin film (I) can be obtained, for example, by applying the thermosetting resin composition to a support, and then drying and semi-curing (B-staged). The semi-curing (B-stage) is preferably performed so that the viscosity of the thermosetting resin composition is such that the workability of the laminate is good. The drying conditions are, for example, 90 to 130 ° C. for 1 to 10 minutes.
Examples of the support include organic films such as polyethylene terephthalate (hereinafter, also referred to as “PET”), biaxially stretched polypropylene, polyethylene, polyvinylfluorate, and polyimide; copper, aluminum, and alloy films of these metals; these organic films or Examples thereof include a film in which the surface of a metal film is subjected to a mold release treatment with a mold release agent. Among these, PET film is preferable from the viewpoint of price and handleability.
The thickness of the support is preferably 10 to 120 μm, more preferably 15 to 80 μm, and even more preferably 15 to 70 μm from the viewpoint of handleability.
Further, workability is good when a protective film is laminated on the surface to which the thermosetting resin composition is applied and semi-cured, and the thermosetting resin composition is sandwiched and wound. The protective film can be made of the same material as the support.

The thickness of the resin film (I) (excluding the thickness of the support and the protective film) may be appropriately determined according to the thickness of the aggregate or the like, and the resin film (I) thinner than the thickness of the aggregate may be used. When used, another resin film (I) may be laminated again on the resin film (I) laminated on the aggregate.
When a plurality of resin films (I) are used, those having different thermosetting degrees, compounding composition, etc. of the film (I) may be used in combination.
The solid content of the thermosetting resin composition in the prepreg is preferably 20 to 90% by mass, more preferably 30 to 85% by mass, and even more preferably 40 to 80% by mass.

[Prepreg for coreless board]
The prepreg for a coreless substrate of the present invention is a prepreg for a coreless substrate manufactured by the method for manufacturing a prepreg for a coreless substrate of the present invention.

From the viewpoint of reliability at the time of package formation, the prepreg of the present invention has a dimensional change rate (i) after etching measured according to the following measuring method of −8.0 to +8.0% and at 170 ° C. for 1 hour. The dimensional change rate (ii) after heating is preferably -4.0 to + 4.0%, and the dimensional change rate (i) after etching is -5.0 to + 5.0%, and It is more preferable that the dimensional change rate (ii) after heating at 170 ° C. for 1 hour is −2.5 to + 2.5%.
<Measurement method of dimensional change rate>
A 250 cm square copper-clad laminate having 12 μm-thick electrolytic copper foils on both surfaces of the prepreg is used as an evaluation substrate, and a total of four reference holes are provided adjacent to each other in a portion 1 cm vertically and 1 cm horizontally from the four corners. Using the average value of the distance between holes as the standard dimension,
After removing the copper foil by immersing the evaluation board in a copper etching solution, the average value of the distances between adjacent holes is defined as the post-etching dimension.
After heating the evaluation substrate after etching at 170 ° C. for 1 hour, the average value of the distances between adjacent holes is defined as the dimension after heating.
Based on the following equations, the dimensional change rate (i) after etching and the dimensional change rate (ii) after heating at 170 ° C. for 1 hour are calculated respectively.
Dimensional change rate (i) (%) = (post-etching dimension-standard dimension) x 100 / standard dimension Dimensional change rate (ii) (%) = (post-heating dimension-post-etching dimension) x 100 / post-etching dimension

From the viewpoint of improving productivity such as improving yield and reducing the amount of warpage of the package, the prepreg of the present invention preferably has a thickness accuracy value of 10% or less, preferably 7.5%, measured according to the following measuring method. Is more preferable.
<Measurement method of thickness accuracy>
A total of 11 points in the width direction in 50 mm increments from the center of the copper-clad laminate having electrolytic copper foils with a thickness of 12 μm on both surfaces of the prepreg, and 10 points in 50 mm increments in the length direction starting from the 11 points. The maximum thickness, the minimum thickness and the average thickness are measured, and the rate of change of the maximum thickness with respect to the average thickness and the rate of change of the minimum thickness with respect to the average thickness are calculated based on the following formula. Each is obtained, and the larger one is used as the value of thickness accuracy.
Maximum thickness change rate (%) = (maximum thickness-average thickness) x 100 / average thickness Minimum thickness change rate (%) = (average thickness-minimum thickness) x 100 / average thickness More specifically, the thickness accuracy can be measured by the method described in the examples.

From the viewpoint of reducing the amount of warpage of the package, the prepreg of the present invention preferably has an elastic modulus of 8 to 35 GPa, more preferably 10 to 20 GPa.
Here, it is generally known that the coefficient of thermal expansion of the prepreg follows the Scapery equation represented by the following equation (1).
A≈ (ArErFr + AgEgFg) / (ErFr + EgFg) (1)
(In the above equation (1), A is the coefficient of thermal expansion of the prepreg, Ar is the coefficient of thermal expansion of the resin composition, Er is the coefficient of elasticity of the resin composition, Fr is the coefficient of integral expansion of the resin composition, and Ag is the glass cloth. The coefficient of thermal expansion, Eg represents the elastic coefficient of the glass cloth, and Fg represents the body integration rate of the glass cloth.)
Therefore, when glass cloth having the same physical properties at an arbitrary volume fraction is used, it is preferable to reduce the elastic modulus and the thermal expansion coefficient of the resin composition.
The elastic modulus of the cured product can be measured by the method described in Examples.

From the viewpoint of reducing the amount of warpage of the package, the prepreg of the present invention preferably has a coefficient of thermal expansion of the cured product of 3.0 to 6.7 ppm / ° C., preferably 4.0 to 6.5 ppm / ° C. Is more preferable, and 5.0 to 6.0 ppm / ° C. is even more preferable.
The coefficient of thermal expansion of the cured product can be measured by the method described in Examples.

The thickness of the entire prepreg of the present invention may be appropriately adjusted according to the thickness of the inner layer circuit and the like, but is preferably 10 μm or more, more preferably 20 μm or more from the viewpoint of thinning the substrate, formability and workability. It is preferably 700 μm or less, more preferably 500 μm or less, still more preferably 200 μm or less, still more preferably 100 μm or less, still more preferably 80 μm or less, particularly preferably 50 μm or less, and most preferably 40 μm or less.

[Coreless substrate and its manufacturing method]
The coreless substrate of the present invention contains an insulating layer formed by using the prepreg for the coreless substrate of the present invention.
In the coreless substrate of the present invention, for example, a build-up layer in which a conductor layer and an insulating layer are alternately laminated by using the prepreg of the present invention is formed on a support (core substrate), and then the support is formed. It can be manufactured by a method of separation. The method for forming the build-up layer is not particularly limited, and a known method can be adopted. For example, the buildup layer can be formed by the following method (see FIG. 2).
First, the prepreg 2 of the present invention is arranged on the support (core substrate) 1. The prepreg 2 may be arranged after the adhesive layer is arranged on the support (core substrate) 1. After that, the prepreg 2 is heat-cured to form an insulating layer. Next, a via hole 3 is formed by a drill cutting method, a laser processing method using a YAG laser, a CO ₂ laser, or the like, and then surface roughening treatment and desmear treatment are performed as necessary. Subsequently, the circuit pattern 4 is formed by a subtractive method, a full additive method, a semi-additive method (SAP: Semi Additive Process), a modified semi-additive method (m-SAP: modified Semi Additive Process), or the like. By repeating the above process, the build-up layer 5 is formed. By separating the formed build-up layer 5 from the support (core substrate) 1, a coreless substrate can be obtained. The screw-up layer 5 may be formed on one side of the support (core substrate) 1 or on both sides.
The coreless substrate of the present invention contains one or more insulating layers obtained by curing the prepreg of the present invention, and may include an insulating layer obtained by curing a prepreg, a resin film, or the like other than the prepreg of the present invention. good.
The thickness of the coreless substrate of the present invention is usually small because it does not have a core substrate, and specifically, it is preferably 15 to 200 mm, more preferably 30 to 150 mm, still more preferably 35 to 100 mm.

[Semiconductor package]
The semiconductor package of the present invention is formed by mounting a semiconductor element on the coreless substrate of the present invention, and is manufactured, for example, by mounting a semiconductor element such as a semiconductor chip or a memory at a predetermined position on the coreless substrate.

Next, the present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention.

[Manufacturing of modified polyimide (X)]
Production Example X1: Synthesis of Modified Polyimide (X-1) In a reaction vessel with a volume of 2 liters that can be heated and cooled equipped with a thermometer, a stirrer and a moisture quantifier with a reflux condenser, both-ended diamine-modified siloxane (Shinetsu Chemical Co., Ltd.) 72 g of Kogyo Co., Ltd., trade name: X-22-161A), 252 g of bis (4-maleimidephenyl) methane (Nippon Kayaku Co., Ltd., trade name: BMI), and 270. 0 g was added and reacted at 110 ° C. for 3 hours to obtain a modified polyimide (X-1) -containing solution.

Production Example X2: Synthesis of Modified Polyimide (X-2) In a reaction vessel with a volume of 2 liters that can be heated and cooled equipped with a thermometer, a stirrer and a moisture meter with a reflux condenser, both-ended diamine-modified siloxane (Shinetsu Chemical Co., Ltd.) 85g of Kogyo Co., Ltd., trade name: X-22-161B) and 2,2-bis [4- (4-maleimidephenoxy) phenyl] propane (manufactured by Nippon Kayaku Co., Ltd., trade name: BMI-4000) 289 g and 270.0 g of propylene glycol monomethyl ether were added and reacted at 110 ° C. for 3 hours to obtain a modified polyimide (X-2) -containing solution.

[Making varnish]
Production Examples 1 to 12
Each component shown below is mixed at the blending ratio shown in Table 1 (the numerical value in the table is the mass part of the solid content, and in the case of a solution or a dispersion liquid, it is the solid content equivalent amount) to obtain an organic solvent. Using methyl ethyl ketone, a uniform varnish-like thermosetting resin composition having a solid content concentration of 65% by mass (hereinafter, also simply referred to as “wanis”) was prepared. The details of the components used in each example are as follows.

[Modified polyimide (X)]
X-1: Modified polyimide (X-1) synthesized in Production Example X1
X-2: Modified polyimide (X-2) synthesized in Production Example X2

[Maleimide compound (a)]
・ BMI: Bis (4-maleimidephenyl) methane [manufactured by Keiai Kasei Co., Ltd., trade name]
BMI-4000: 2,2-bis [4- (4-maleimide phenoxy) phenyl] propane [manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name]

[Amine compound (b)]
X-22-161A: Diamine-modified siloxane at both ends [manufactured by Shin-Etsu Chemical Co., Ltd., trade name, functional group equivalent of amino group: 800 g / mol]
X-22-161B: Diamine-modified siloxane at both ends [manufactured by Shin-Etsu Chemical Co., Ltd., trade name, functional group equivalent of amino group: 1,500 g / mol]

[Thermoplastic elastomer (c)]
Epofriend (registered trademark) CT-310: Epoxy-modified styrene-butadiene copolymer resin [manufactured by Daicel Corporation, trade name]
Tough Tech (registered trademark) M1913: Carboxylic acid-modified hydrogenated styrene-butadiene copolymer resin [manufactured by Asahi Kasei Chemicals Co., Ltd., trade name]
SG-P3: Epoxy group-containing acrylic thermoplastic elastomer [manufactured by Nagase ChemteX Corporation, trade name]

[Thermosetting resin (d)]
NC-7000-L: Naphthalene skeleton-containing epoxy resin (more specifically, α-naphthol / cresol novolac type epoxy resin) [Nippon Kayaku Co., Ltd., trade name]
-NC-3000-H: Biphenyl aralkyl type epoxy resin [manufactured by Nippon Kayaku Co., Ltd., product name]

[Curing accelerator (e)]
G-8009L: Isocyanate mask imidazole [manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name]
-TPP-S: Triphenylphosphine Triphenylborane [manufactured by Hokuko Chemical Industry Co., Ltd., trade name]

[Inorganic filler (f)]
-SC2050-KNK: Fused silica (manufactured by Admatex Co., Ltd., trade name, average particle size: 0.5 μm)

[Prepreg preparation: Method (A)]
Examples 1 to 6
The varnish obtained above is applied to a PET film having a width of 580 mm (manufactured by Teijin DuPont Film Co., Ltd., trade name: G2) so that the coating width is 525 mm and the dried resin layer has a predetermined thickness. It was adjusted and applied, and dried at 120 ° C. for 3 minutes to prepare a resin film with a support.
Next, a resin film with a support is placed on both surfaces of the glass cloth as an aggregate so that the resin layer faces the glass cloth, and is sandwiched between pressure rolls to support both surfaces of the glass cloth. A resin film with a body was pressed and attached, and a thermosetting resin composition was impregnated into a glass cloth to prepare a prepreg. After that, it was cooled with a cooling roll and wound up.
The pressure roll conditions were a roll temperature of 100 ° C., a linear pressure of 0.2 MPa, and a speed of 2.0 m / min.
The content of the thermosetting resin composition in the obtained prepreg, the thickness of the glass cloth, and the type of the glass cloth are shown in the section of the measuring method described later.

[Prepreg preparation: Method (B)]
Comparative Examples 1 to 6
The varnish obtained above is applied to a glass cloth as an aggregate using a coating machine, and then dried at 130 ° C. for 10 minutes to remove the solvent and semi-cure the thermosetting resin composition. , A prepreg was prepared. The coating amount was adjusted by the squeeze roll method.
The content of the thermosetting resin composition in the obtained prepreg, the thickness of the glass cloth, and the type of the glass cloth are shown in the section of the measuring method described later.

[Copper-clad laminate]
Using the prepreg obtained above, a copper-clad laminate was produced. For the copper-clad laminate, a predetermined number of prepregs determined according to the evaluation items described later and electrolytic copper foils (thickness: 12 μm) are arranged above and below the prepreg, and pressed at a pressure of 2.5 MPa and a temperature of 240 ° C. for 60 minutes. Was produced.

[Measuring method]
The prepreg was evaluated by the measurement method shown below. The evaluation results are shown in Table 1.

(1) Dimensional change rate In the production of the above copper-clad laminate, the prepregs obtained in each example (resin composition content 78% by mass, glass cloth thickness: 9.6 μm, glass cloth) were used as prepregs. Type: E glass cloth, total thickness of prepreg: 25 μm) Two sheets were used to obtain a copper-clad laminate. The copper-clad laminate cut out into 250 cm squares is used as an evaluation substrate, and a total of four reference holes are provided in the sections 1 cm vertically and 1 cm horizontally from the four corners, and a CNC image measuring machine (manufactured by Mitutoyo Co., Ltd., trade name) is provided. : QV-H606T1L-D) was used to measure the distance between adjacent holes, and the average value was used as the reference dimension.
Next, the copper foil was removed by immersing the evaluation substrate in a copper etching solution (type of chemical solution: ammonium persulfate, temperature: 40 ° C., treatment time: 5 minutes), and then the adjacent holes were separated by the same method. The distance was measured, and the average value was taken as the dimension after etching.
Subsequently, the evaluation substrate from which the copper foil was removed by etching was heated in air at 170 ° C. for 1 hour, the distance between adjacent holes was measured by the same method, and the average value was measured after heating. And said.
From each of the dimensions obtained above, the dimensional change rate (i) after etching and the dimensional change rate (ii) after heating at 170 ° C. for 1 hour were calculated based on the following equations.
Dimensional change rate (i) = (post-etching dimension-standard dimension) x 100 / standard dimension Dimensional change rate (ii) = (post-heating dimension-post-etching dimension) x 100 / post-etching dimension

(2) Thickness accuracy In the production of the above copper-clad laminate, the prepregs obtained in each example (resin composition content 78% by mass, glass cloth thickness: 9.6 μm, glass cloth type) were used as prepregs. : E glass cloth, total thickness of prepreg: 25 μm) A copper-clad laminate was obtained using one sheet.
A total of 11 points in the width direction in 50 mm increments from the center of the obtained copper-clad laminate in the width direction, and 10 points in 50 mm increments in the length direction starting from each of the 11 points (that is, 11 points x 10 points = 110 points). ) Is measured in units of 0.001 mm using an upright gauge, the maximum thickness, minimum thickness and average thickness are obtained, and the change in maximum thickness with respect to the average thickness is obtained based on the following formula. The rate of change of the minimum thickness with respect to the rate and the average thickness are obtained, and the larger one is used as the value of the thickness accuracy.
Maximum thickness change rate (%) = (maximum thickness-average thickness) x 100 / average thickness Minimum thickness change rate (%) = (average thickness-minimum thickness) x 100 / average thickness

(3) Coefficient of thermal expansion In the production of the above copper-clad laminate, the prepregs obtained in each example (resin composition content 48% by mass, glass cloth thickness: 0.10 mm, glass cloth) were used as prepregs. Type: E glass cloth, total thickness of prepreg: 0.11 mm) 4 sheets were used to obtain a copper-clad laminate. A 5 mm square evaluation substrate from which the copper foil was removed was prepared by immersing the copper-clad laminate in a copper etching solution, and thermomechanical analysis was performed by a compression method using a TMA test device (TMA2940, manufactured by DuPont). .. After the evaluation substrate was mounted on the apparatus in the X direction, the measurement was carried out twice in succession under the measurement conditions of a load of 5 g and a heating rate of 10 ° C./min. The average coefficient of thermal expansion from 30 ° C. to 100 ° C. in the second measurement was calculated and used as the value of the coefficient of thermal expansion.

(4) Flexural modulus In the production of the above copper-clad laminate, the prepregs obtained in each example (resin composition content 48% by mass, glass cloth thickness: 0.10 mm, glass cloth) were used as prepregs. Type: E glass cloth, total thickness of prepreg: 0.11 mm) 4 sheets were used to obtain a copper-clad laminate. A 50 mm × 25 mm evaluation substrate from which the copper foil was removed was prepared by immersing the copper-clad laminate in a copper etching solution, and a 5-ton tencilon manufactured by Orientec Co., Ltd. was used at a crosshead speed of 1 mm / min and between spans. The flexural modulus was measured under the condition of a distance of 20 mm.

From Table 1, it can be seen that the prepregs of Examples 1 to 6 obtained by the production method of the present invention have a small dimensional change rate and a small thickness variation. Further, the degree of increase in the dimensional change rate when the flexural modulus is reduced is that the prepregs of Examples 1 to 6 obtained by the manufacturing method of the present invention are compared with Comparative Examples 1 to 6 manufactured by the conventional manufacturing method. It can be seen that it is significantly reduced compared to the prepreg.
From the above results, it can be seen that the manufacturing method of the present invention has good workability, and that the manufacturing method of the present invention can obtain a prepreg for a coreless substrate having excellent thickness accuracy and dimensional stability.

1 Prepreg manufacturing equipment 2 Aggregate delivery device 3 Resin film delivery device 4 Protective film peeling mechanism 5 Protective film winding device 6 Sheet heating and pressurizing device (film pressure welding means)
7 Sheet pressure cooling device 8 Prepreg winding device 40 Aggregate 40a Surface of aggregate (one surface of aggregate, one of both surfaces of aggregate)
40b Back side of aggregate (the other surface of the aggregate, the other of both surfaces of the aggregate)
50 Resin film with protective film (I)
52 Protective film 54 Resin film (I)
54a The surface of the resin film (I) on the aggregate side (the surface of the film on the aggregate side)
60 prepreg

Claims (14)

A method for producing a prepreg for a coreless substrate, wherein a resin film (I) containing a thermosetting resin composition is attached to at least one surface of a sheet-shaped aggregate.
The pasting is performed by a film pressure welding step in which the resin film (I) is pressure-welded to at least one surface of the sheet-shaped aggregate under normal pressure.
The coreless substrate prepreg has a dimensional change rate (i) of −8.0 to +8.0% after etching measured according to the following measurement method, and a dimensional change rate (ii) after heating at 170 ° C. for 1 hour. Is a method for manufacturing a prepreg for a coreless substrate, which is -4.0 to + 4.0%.
<Measurement method of dimensional change rate>
A 250 cm square copper-clad laminate having 12 μm-thick electrolytic copper foils on both surfaces of the prepreg is used as an evaluation substrate, and a total of four reference holes are provided adjacent to each other in a portion 1 cm vertically and 1 cm horizontally from the four corners. Using the average value of the distance between holes as the standard dimension,
After removing the copper foil by immersing the evaluation board in a copper etching solution, the average value of the distances between adjacent holes is defined as the post-etching dimension.
The evaluation substrate after etching is calculated based on the following formula with the average value of the distances between adjacent holes after heating at 170 ° C. for 1 hour as the dimension after heating.
Dimensional change rate (i) (%) = (post-etching dimension-standard dimension) x 100 / standard dimension Dimensional change rate (ii) (%) = (post-heating dimension-post-etching dimension) x 100 / post-etching dimension A method for producing a prepreg for a coreless substrate, wherein a resin film (I) containing a thermosetting resin composition is attached to at least one surface of a sheet-shaped aggregate.
The pasting is performed by a film pressure welding step in which the resin film (I) is pressure-welded to at least one surface of the sheet-shaped aggregate under normal pressure.
The coreless substrate prepreg is a method for manufacturing a coreless substrate prepreg, wherein the thickness accuracy value measured according to the following measuring method is 10% or less.
<Measurement method of thickness accuracy>
A total of 11 points in the width direction in 50 mm increments from the center of the copper-clad laminate having electrolytic copper foils with a thickness of 12 μm on both surfaces of the prepreg, and 10 points in 50 mm increments in the length direction starting from the 11 points. The maximum thickness, the minimum thickness and the average thickness are measured, and the rate of change of the maximum thickness with respect to the average thickness and the rate of change of the minimum thickness with respect to the average thickness are calculated based on the following formula. Each is obtained, and the larger value is used as the thickness accuracy value.
Maximum thickness change rate (%) = (maximum thickness-average thickness) x 100 / average thickness Minimum thickness change rate (%) = (average thickness-minimum thickness) x 100 / average thickness A method for producing a prepreg for a coreless substrate, wherein a resin film (I) containing a thermosetting resin composition is attached to at least one surface of a sheet-shaped aggregate.
The pasting is performed by a film pressure welding step in which the resin film (I) is pressure-welded to at least one surface of the sheet-shaped aggregate under normal pressure.
The coreless substrate prepreg is a method for manufacturing a coreless substrate prepreg, wherein the elastic modulus of the cured product is 10 to 20 GPa. The method for manufacturing a prepreg for a coreless substrate according to any one of claims 1 to 3, wherein the film pressure welding step is a step of pressing the resin film (I) against both surfaces of the sheet-shaped aggregate. .. The film pressure welding step heats the resin film (I) in the range of -40 ° C to + 20 ° C, which is the minimum melt viscosity temperature of the resin film (I), while heating at least one surface of the sheet-like aggregate. The method for manufacturing a prepreg for a coreless substrate according to any one of claims 1 to 4, which is a step of pressure-welding to the coreless substrate. The resin film (I) has a maleimide compound (a) having at least two N-substituted maleimide groups in one molecule, an amine compound (b) having at least two primary amino groups in one molecule, and The method for producing a prepreg for a coreless substrate according to any one of claims 1 to 5, which comprises a thermosetting resin composition containing a thermoplastic elastomer (c). The resin film (I) comprises a maleimide compound (a) having at least two N-substituted maleimide groups in one molecule and an amine compound (b) having at least two primary amino groups in one molecule. The present invention according to any one of claims 1 to 6, which comprises a thermosetting resin composition containing a modified polyimide (X) which is a reaction product of the above and a thermoplastic elastomer (c). How to make prepregs for coreless substrates. The method for producing a prepreg for a coreless substrate according to claim 6 or 7, wherein the thermosetting resin composition further contains a thermosetting resin (d). The method for producing a prepreg for a coreless substrate according to any one of claims 1 to 8, wherein the sheet-like aggregate has a thickness of 0.002 to 0.5 mm. The method for manufacturing a prepreg for a coreless substrate according to any one of claims 1 to 9, wherein the prepreg for a coreless substrate has a coefficient of thermal expansion of a cured product of 5.0 to 6.5 ppm / ° C. A prepreg for a coreless substrate manufactured by the method for manufacturing a prepreg for a coreless substrate according to any one of claims 1 to 10. A method for manufacturing a coreless substrate, wherein an insulating layer is formed by using the prepreg for a coreless substrate according to claim 11. A method for manufacturing a semiconductor package in which a semiconductor element is mounted on a coreless substrate manufactured by the method for manufacturing a coreless substrate according to claim 12. A method for manufacturing a coreless substrate, wherein a build-up layer formed by alternately laminating conductor layers and insulating layers is formed on a support, and then the build-up layer is separated from the support. A method for manufacturing a coreless substrate, wherein at least one layer of the above is formed by using the prepreg for a coreless substrate manufactured by the method for manufacturing a prepreg for a coreless substrate according to any one of claims 1 to 10.

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