JP2019161206A - Manufacturing method of thermoplastic liquid crystal polymer multilayer structure - Google Patents

Abstract

To provide a manufacturing method of a multilayer structure formed by thermoplastic liquid crystal polymer.SOLUTION: The manufacturing method includes: a shape fixing step for boosting a heat press machine 300 to first pressure at less than thermocompression bonding temperature of thermoplastic liquid crystal polymer, pressurizing a preparatory laminate 130 by a heat-resisting cushioning material 150 and a metal plate 152 through protection materials 142, 144, sealing ends of the protection materials 142, 144 by pressure application of the heat-resisting cushioning material 150 on the side of the preparatory laminate 130, wrapping the preparatory laminate 130 in a state that the protection materials 142, 144 are brought into contact with all side faces of the preparatory laminate 130 to fix a shape so that the preparatory laminate 130 becomes a desired shape of the thermoplastic liquid crystal polymer multilayer structure; and a thermocompression bonding step for decompressing the first pressure, increasing the temperature up to a thermocompression bonding temperature under second pressure lower than the first pressure to thermally compress adjacent thermoplastic liquid crystal polymer sub-structure.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method for producing a thermoplastic liquid crystal polymer multilayer structure composed of a thermoplastic polymer capable of forming an optically anisotropic molten phase (hereinafter referred to as a thermoplastic liquid crystal polymer).

  The thermoplastic liquid crystal polymer is a material useful as a dielectric layer for forming a multilayer circuit board and the like because it has heat resistance despite being a material that can be bonded by thermocompression bonding. In forming a multilayer circuit board, it is advantageous to increase the production efficiency by laminating a large number of thermoplastic liquid crystal polymer layers at once. However, in the multilayering process, it is necessary to perform processing at a high temperature, and a new manufacturing method is required for increasing the number of liquid crystal polymer layers.

  As a manufacturing method for increasing the number of layers, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2006-049502), a laminate in which a resin film and a conductor pattern are laminated is disposed between hot press plates, and at least Heating / pressurizing the laminate from above and below by the hot press plate with a buffer member according to the arrangement of the conductor pattern interposed between the surface of the laminate and the hot press plate. A method for manufacturing a multilayer substrate comprising a pressing step is disclosed.

JP 2006-049502 A

  In Patent Document 1, the unevenness on the surface of the multilayer substrate is transferred to the buffer member after heating and pressurization, and the buffer member cannot be used repeatedly, and individual buffer members are used according to the arrangement of the conductor pattern. It is characterized by that. However, using individual buffer members in accordance with the arrangement of the conductor pattern complicates the manufacturing method and is inefficient.

Therefore, an object of the present invention is to provide a method for efficiently producing a thermoplastic liquid crystal polymer multilayer structure by a simple production method while suppressing excessive flow of the thermoplastic liquid crystal polymer and collapsing of the shape of the circuit layer. There is to do.
Another object of the present invention is to provide a method for producing a thermoplastic liquid crystal polymer multilayer structure that can repeatedly use the heat-resistant cushioning material used in the production method, and that reduces the production cost.

  The inventors of the present invention have intensively studied to achieve the above object, and as a result, unlike a general plastic, a thermoplastic liquid crystal polymer has a very low shear rate and an extremely low melt viscosity. When heating and pressurizing with a heat press machine with a buffer member interposed in order to produce a structure, the pattern derived from the buffer member is transferred to the surface of the thermoplastic liquid crystal polymer multilayer structure at the thermocompression bonding temperature. I found out.

  As a result of further research, (i) in a heat press machine, a metal plate is interposed between a cushion material formed of heat-resistant fibers and a protective material for protecting the thermoplastic liquid crystal polymer multilayer structure, (Ii) When the thermoplastic liquid crystal polymer multilayer structure is pressurized with a heat-resistant cushion material and a metal plate at a temperature lower than the thermocompression bonding temperature, and the side of the multilayer structure is sealed with a heat-resistant cushion material, iii) It has been found that the thermoplastic liquid crystal polymer multilayer structure can be fixed in a desired shape by the protective material, and (iv) during thermocompression bonding, the pressure is applied at a pressure lower than the pressure applied to fix the shape. When the temperature is increased to the thermocompression bonding temperature and the heat pressing is performed, (v) the thermocompression bonding can be performed satisfactorily while the shape of the thermoplastic liquid crystal polymer multilayer structure is fixed by the protective material. The surface of the thermoplastic liquid crystal polymer multilayer structure is not adversely affected by the heat cushioning material, further, it heat-resistant cushion material is repeatedly available, finding, and have completed the present invention.

That is, the present invention can be configured in the following manner.
[Aspect 1]
Selected from the group consisting of (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a thermoplastic liquid crystal polymer film having a conductor layer on both sides. A pre-laminated body in which at least two thermoplastic liquid crystal polymer substructures are superposed is heated and pressurized in a hot press machine through protective materials disposed on the upper and lower surfaces thereof to produce a thermoplastic liquid crystal polymer multilayer structure. A method,
On at least one of the upper and lower surfaces of the preliminary laminate, a heat-resistant cushion material and a metal plate are arranged in order from the hot press side,
Below the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, the hot press is pressurized to the first pressure, and (I) the preliminary laminate is pressurized with the heat-resistant cushioning material and the metal plate through the protective material. (II) At the side of the preliminary laminate, the end of the protective material is sealed by pressurization of the heat-resistant cushion material, and (III) the protective material is in contact with all side surfaces of the preliminary laminate. A shape fixing step of fixing the shape so that the preliminary laminated body becomes the shape of a desired thermoplastic liquid crystal polymer multilayer structure by wrapping the preliminary laminated body in a state;
A thermocompression bonding step of depressurizing from the first pressure, raising the temperature to a thermocompression bonding temperature under a second pressure lower than the first pressure, and thermocompression bonding the adjacent thermoplastic liquid crystal polymer substructure;
A method for producing a thermoplastic liquid crystal polymer multilayer structure comprising:
[Aspect 2]
The manufacturing method according to aspect 1, wherein the conductor layer is selected from the group consisting of a conductor pattern, a conductor foil, and a conductor film,
When a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure,
The protective material in contact with the surface on which the conductor pattern is formed is a multilayer composite material that can be deformed according to the shape of the conductor pattern,
The manufacturing method in which the protective material in contact with the surface on which the conductor pattern is not formed is a single layer sheet.
[Aspect 3]
3. The manufacturing method according to aspect 2, wherein the multilayer composite material is formed of a first metal foil, a pair of high-density polyethylene sheets whose MD directions are orthogonal to each other, a second metal foil, and a low-friction film. Manufacturing method.
[Aspect 4]
The manufacturing method according to any one of aspects 1 to 3, wherein the heat resistant cushion material is a heat resistant fiber cushion material.
[Aspect 5]
It is a manufacturing method of aspect 4, Comprising: The manufacturing method whose said heat resistant fiber cushion material is an organic fiber nonwoven fabric whose melting | fusing point or thermal decomposition temperature is 260 degreeC or more, or a metal fiber nonwoven fabric.
[Aspect 6]
It is a manufacturing method as described in any one aspect of aspect 1-5, Comprising: The manufacturing method whose difference of a 1st pressure and a 2nd pressure is 0.8-2.5 MPa.
[Aspect 7]
It is a manufacturing method as described in any one aspect of aspect 1-6, Comprising: The length ( _CL ) of the vertical direction of the said heat-resistant cushioning material and the length ( _CW ) of the side of a horizontal direction are preliminary laminated bodies. A manufacturing method having the following relationship with respect to the vertical length (P _L ) and the horizontal side length (P _W ).
P _L + 1 ≦ C _L ≦ P _L +10 (unit: cm) and P _W + 1 ≦ C _W ≦ P _W +10 (unit: cm)
[Aspect 8]
A process according to any one of Embodiments 1 to 7, the vertical length (M _L) and transverse side length of the metal plate (M _W) is, the heat-resistant cushion material In the longitudinal direction (C _L ) and the lateral side length (C _W ), the longitudinal length (P _L ) and the lateral side length (P _W ) of the preliminary laminate. On the other hand, a manufacturing method having the following relationship.
P _L −1.0 ≦ M _L ≦ P _L (unit: cm)
P _W −1.0 ≦ M _W ≦ P _W (unit: cm)
C _L −11 ≦ M _L ≦ C _L −1.2 (unit: cm) and C _W −11 ≦ M _W ≦ C _W −1.2 (unit: cm)

  In this invention, while being able to manufacture a thermoplastic liquid crystal polymer multilayer structure efficiently, the heat-resistant cushioning material used in the case of manufacture can be repeatedly utilized, and manufacturing cost can be reduced.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. The drawings are not necessarily drawn to scale, but are exaggerated in illustrating the principles of the invention.
It is a schematic sectional drawing for demonstrating the state before a shape fixing process about the manufacturing method of the thermoplastic liquid crystal polymer multilayer structure by 1st embodiment of this invention. It is a schematic sectional drawing for demonstrating the state which applies a pressure to a preliminary | backup laminated body in the shape fixing process about embodiment of FIG. It is a schematic sectional drawing for demonstrating the state before a shape fixing process about the manufacturing method of the thermoplastic liquid crystal polymer multilayer structure by 2nd embodiment of this invention. It is a schematic sectional drawing for demonstrating the state before a shape fixing process about the manufacturing method of the thermoplastic liquid crystal polymer multilayer structure by 3rd embodiment of this invention. FIG. 5 is a schematic cross-sectional view for explaining a state in which pressure is applied to the pre-laminated body in the shape fixing step for the embodiment of FIG. 4. It is a schematic sectional drawing for demonstrating the state before a shape fixing process about the manufacturing method of the thermoplastic liquid crystal polymer multilayer structure by Comparative Examples 4-8. It is a schematic sectional drawing for demonstrating the state before a shape fixing process about the manufacturing method of the thermoplastic liquid crystal polymer multilayer structure by Comparative Examples 9-13.

  In the method for producing a thermoplastic liquid crystal polymer multilayer structure of the present invention, (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a conductor layer on both sides. A pre-laminated body in which at least two thermoplastic liquid crystal polymer substructures selected from the group consisting of thermoplastic liquid crystal polymer films on the surface are superposed is heated by specific heating and pressure control from the upper and lower surfaces in a hot press machine. A thermoplastic liquid crystal polymer multilayer structure in which the adjacent thermoplastic liquid crystal polymer substructures are bonded is manufactured by pressure bonding.

(Thermoplastic liquid crystal polymer)
The thermoplastic liquid crystal polymer is composed of a liquid crystal polymer that can be melt-molded (or a polymer that can form an optically anisotropic melt phase), and the thermoplastic liquid crystal polymer can be any liquid crystal polymer that can be melt-molded. The chemical structure is not particularly limited, and examples thereof include a thermoplastic liquid crystal polyester or a thermoplastic liquid crystal polyester amide having an amide bond introduced therein.

  Further, the thermoplastic liquid crystal polymer may be a polymer in which an isocyanate-derived bond such as an imide bond, a carbonate bond, a carbodiimide bond, or an isocyanurate bond is further introduced into an aromatic polyester or an aromatic polyester amide.

  Specific examples of the thermoplastic liquid crystal polymer used in the present invention include known thermoplastic liquid crystal polyesters and thermoplastic liquid crystal polyester amides derived from the compounds (1) to (4) listed below and derivatives thereof. Can be mentioned. However, it goes without saying that there is an appropriate range of combinations of various raw material compounds in order to form a polymer capable of forming an optically anisotropic melt phase.

(1) Aromatic or aliphatic dihydroxy compounds (see Table 1 for typical examples)

(2) Aromatic or aliphatic dicarboxylic acids (see Table 2 for typical examples)

(3) Aromatic hydroxycarboxylic acids (see Table 3 for typical examples)

(4) Aromatic diamine, aromatic hydroxyamine or aromatic aminocarboxylic acid (see Table 4 for typical examples)

  Representative examples of the liquid crystal polymer obtained from these raw material compounds include copolymers having the structural units shown in Tables 5 and 6.

  Among these copolymers, a polymer containing at least p-hydroxybenzoic acid and / or 6-hydroxy-2-naphthoic acid as a repeating unit is preferable. In particular, (i) p-hydroxybenzoic acid and 6-hydroxy- A polymer containing a repeating unit with 2-naphthoic acid, or (ii) at least one aromatic hydroxycarboxylic acid selected from the group consisting of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, and at least one kind A copolymer containing a repeating unit of an aromatic diol and at least one aromatic dicarboxylic acid is preferred.

  For example, in the polymer (i), when the thermoplastic liquid crystal polymer contains at least repeating units of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, p-hydroxybenzoic acid of the repeating unit (A) And the molar ratio (A) / (B) of the repeating unit (B) to 6-hydroxy-2-naphthoic acid is about (A) / (B) = 10/90 to 90/10 in the liquid crystal polymer. Desirably, it is desirable that (A) / (B) = about 15/85 to 85/15, and more preferably (A) / (B) = 20/80 to 80/20. It may be a degree.

  In the case of the polymer (ii), at least one aromatic hydroxycarboxylic acid (C) selected from the group consisting of p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, and 4,4′-dihydroxy At least one aromatic diol (D) selected from the group consisting of biphenyl, hydroquinone, phenylhydroquinone and 4,4′-dihydroxydiphenyl ether, and a group consisting of terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid The molar ratio of each repeating unit in the liquid crystal polymer of at least one kind of aromatic dicarboxylic acid (E) is aromatic hydroxycarboxylic acid (C): aromatic diol (D): aromatic dicarboxylic acid (E) = (30-80): (35-10): (35-10) More preferably, it may be (C) :( D) :( E) = (35-75) :( 32.5-12.5) :( 32.5-12.5), Preferably, it may be about (C) :( D) :( E) = (40-70) :( 30-15) :( 30-15).

  The molar ratio of the repeating unit derived from 6-hydroxy-2-naphthoic acid in the aromatic hydroxycarboxylic acid (C) may be, for example, 85 mol% or more, preferably 90 mol% or more, more Preferably, it may be 95 mol% or more. The molar ratio of the repeating unit derived from 2,6-naphthalenedicarboxylic acid in the aromatic dicarboxylic acid (E) may be, for example, 85 mol% or more, preferably 90 mol% or more, more preferably 95 mol. % Or more.

  The aromatic diol (D) is a repeating unit derived from two different aromatic diols selected from the group consisting of hydroquinone, 4,4′-dihydroxybiphenyl, phenylhydroquinone, and 4,4′-dihydroxydiphenyl ether. (D1) and (D2) may be sufficient. In this case, the molar ratio of the two aromatic diols may be (D1) / (D2) = 23/77 to 77/23, and more preferably. May be 25/75 to 75/25, more preferably 30/70 to 70/30.

  Moreover, it is preferable that the molar ratio of the repeating structural unit derived from the aromatic diol and the repeating structural unit derived from the aromatic dicarboxylic acid is (D) / (E) = 95/100 to 100/95. Outside this range, the degree of polymerization does not increase and the mechanical strength tends to decrease.

  Note that the optically anisotropic melt phase referred to in the present invention can be formed, for example, by placing the sample on a hot stage, heating and heating in a nitrogen atmosphere, and observing the transmitted light of the sample. .

  The thermoplastic liquid crystal polymer preferably has a melting point (hereinafter referred to as Tm) in the range of 260 to 360 ° C, and more preferably has a Tm of 270 to 350 ° C. Tm is obtained by measuring the temperature at which the main endothermic peak appears with a differential scanning calorimeter (Shimadzu Corporation DSC).

  The thermoplastic liquid crystal polymer may be a thermoplastic polymer such as polyethylene terephthalate, modified polyethylene terephthalate, polyolefin, polycarbonate, polyarylate, polyamide, polyphenylene sulfide, polyether ether ketone, and fluororesin within a range not impairing the effects of the present invention. Various additives and fillers may be added.

  The thermoplastic liquid crystal polymer film is obtained, for example, by extruding a melt-kneaded product of the thermoplastic liquid crystal polymer. Any method can be used as the extrusion molding method, but the well-known T-die method, inflation method and the like are industrially advantageous. In particular, in the inflation method, stress is applied not only in the mechanical axis direction (hereinafter abbreviated as MD direction) of the thermoplastic liquid crystal polymer film but also in the direction orthogonal to this (hereinafter abbreviated as TD direction). Since the film can be stretched uniformly in the direction, a thermoplastic liquid crystal polymer film in which the molecular orientation in the MD direction and the TD direction, the dielectric properties, etc. are controlled can be obtained.

  For example, in the extrusion molding by the T-die method, the melt sheet extruded from the T-die may be formed by simultaneously stretching not only in the MD direction of the thermoplastic liquid crystal polymer film but also in both the TD direction and the TD direction. Alternatively, a melt sheet extruded from a T-die may be stretched once in the MD direction and then stretched in the TD direction to form a film.

  In addition, in the extrusion molding by the inflation method, a predetermined draw ratio (corresponding to a stretching ratio in the MD direction) and a blow ratio (corresponding to a stretching ratio in the TD direction) with respect to a cylindrical sheet melt-extruded from a ring die. The film may be formed by stretching.

  The stretch ratio of such extrusion molding may be, for example, about 1.0 to 10, preferably about 1.2 to 7, more preferably about 1. as the stretch ratio (or draw ratio) in the MD direction. It may be about 3-7. Further, the draw ratio (or blow ratio) in the TD direction may be, for example, about 1.5 to 20, preferably about 2 to 15, and more preferably about 2.5 to 14.

(Integration process of conductor layer and thermoplastic liquid crystal polymer film)
When forming a conductive layer (a conductive layer such as a signal layer, a power supply layer, a ground layer, for example, a conductive pattern, a conductive foil, a conductive film, etc.) on a thermoplastic liquid crystal polymer film, it is known or commonly used. The integration step of the conductor layer and the thermoplastic liquid crystal polymer film can be performed by the method. By this integration step, a thermoplastic liquid crystal polymer film having a conductor layer on one side may be produced, or a thermoplastic liquid crystal polymer film having a conductor layer on both sides may be produced.
For example, a metal foil or the like is thermocompression bonded to a thermoplastic liquid crystal polymer film to form a single-sided metal-clad laminate or double-sided metal-clad laminate, and further etched as necessary to form the necessary conductor layer shape. May be.

  The conductor forming the conductor layer may be various conductive metals such as gold, silver, copper, iron, nickel, aluminum, or alloy metals thereof. The thickness of the conductor layer can be appropriately set as necessary, and may be, for example, about 5 to 50 μm, and more preferably in the range of 8 to 35 μm.

  Thus, as the thermoplastic liquid crystal polymer substructure used in the thermoplastic liquid crystal polymer multilayer structure, (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one surface, and (Iii) A thermoplastic liquid crystal polymer film having a conductor layer on both sides can be produced.

(Deaeration drying process)
If necessary, the thermoplastic liquid crystal polymer substructure may be subjected to a degassing drying step for removing air and moisture present in the thermoplastic liquid crystal polymer film. The degassing drying step may be performed on individual thermoplastic liquid crystal polymer substructures and combinations thereof prior to the shape fixing step, or may be performed on the pre-laminated body as part of the shape fixing step. Or both may be performed.

When it is performed prior to the shape fixing step, the degassing drying step is not particularly limited as long as it is performed before the shape fixing step. For example, prior to the step of integrating the thermoplastic liquid crystal polymer film and the conductor layer. Further, it may be performed in a thermoplastic liquid crystal polymer film, or may be performed as part of an integration process of the thermoplastic liquid crystal polymer film and the conductor layer.
By the deaeration drying step, the thermal adhesiveness of the thermoplastic liquid crystal polymer substructure can be improved, and the interlayer adhesiveness of the thermoplastic liquid crystal polymer substructure can be improved.

  The shape of the thermoplastic liquid crystal polymer substructure subjected to the degassing drying step is not particularly limited as long as the thermoplastic liquid crystal polymer film can be degassed and dried. For example, in the degassing drying step, the thermoplastic liquid crystal polymer substructure may be the thermoplastic liquid crystal polymer film itself, or a thermoplastic liquid crystal in which a conductor layer is formed on one or both sides of the thermoplastic liquid crystal polymer film. It may be provided as a sheet of polymer substructure. Furthermore, these thermoplastic liquid crystal polymer substructures may be provided as rolls as necessary.

  Furthermore, if necessary, the thermoplastic liquid crystal polymer substructure may be a multilayer laminate of a plurality of thermoplastic liquid crystal polymer substructures (for example, a multilayer laminate or a temporary assembly in which a plurality of thermoplastic liquid crystal polymer substructures are laminated). The multilayer circuit may be subjected to a degassing and drying step.

  In the degassing drying step, the thermoplastic liquid crystal polymer substructure is subjected to degassing drying under a specific vacuum (for example, vacuum drying) and / or degassing drying under heating (for example, heat drying), It becomes possible to extremely reduce the air and moisture present inside and on the surface of the thermoplastic liquid crystal polymer film. And in the thermoplastic liquid crystal polymer substructure which passed through such a deaeration drying process, it becomes possible to improve the thermal adhesiveness.

  For example, a thermoplastic liquid crystal polymer film that has been subjected to a degassing drying process can achieve high adhesion without performing a softening treatment such as breaking the skin layer. However, the present invention does not deny the softening process. The thermoplastic liquid crystal polymer film may be subjected to a surface treatment such as a softening treatment as necessary.

  In the degassing drying step, the thermoplastic liquid crystal polymer substructure is (a) degassed and dried under vacuum at a vacuum degree of 1500 Pa or less for 30 minutes or more, and / or (b) in the range of 80 ° C to 300 ° C. The thermoplastic liquid crystal polymer film can be deaerated and dried by being deaerated and dried under heating. In the deaeration drying step, the deaeration drying may be performed under a condition that satisfies either (a) the deaeration drying step under vacuum or (b) the deaeration drying step under heating. ) And (b) are preferably degassed and dried under conditions that satisfy both.

  The case of deaeration and drying under conditions satisfying both (a) and (b) means deaeration and drying performed under conditions where both (a) and (b) are satisfied simultaneously (that is, under vacuum heating). A degassing drying process in which the conditions of (a) and (b) are separately performed on the thermoplastic liquid crystal polymer substructure, that is, the order of (a) to (b), or (b ) To (a) may be performed separately in the order of deaeration and drying.

  In addition, when performing a deaeration drying process separately, in the range which does not have a bad influence on the thermal adhesiveness of a thermoplastic liquid crystal polymer film, between (a) and (b) or between (b) and (a) A separate drying step may be performed.

  Moreover, in a deaeration drying process, from a viewpoint of improving deaeration drying property, you may perform deaeration drying under the non-pressurization (under pressure release) which does not substantially pressurize. For example, the degassing drying step may be performed in a low pressure state or in a pressure release state (for example, under a pressure of about 0 to 0.7 MPa, preferably under a pressure of about 0 to 0.5 MPa).

  (A) Deaeration drying under vacuum may be performed at a vacuum degree of 1500 Pa or less, preferably 1300 Pa or less, more preferably 1100 Pa or less. When performing deaeration drying under vacuum independently, it may be carried out at room temperature (for example, in the range of 10 to 50 ° C., preferably in the range of 15 to 45 ° C.). You may go on. The heating temperature in that case may be, for example, 50 to 300 ° C. (for example, 50 to 250 ° C.), preferably 80 to 250 ° C., and more preferably about 80 to 200 ° C.

  (B) Deaeration drying under heating may be performed in the range of 80 to 300 ° C, preferably in the range of 80 to 250 ° C, and more preferably in the range of 80 to 200 ° C. In addition, deaeration drying under heating may set a predetermined temperature range with respect to the melting point Tm of the thermoplastic liquid crystal polymer film. In that case, for example, it may be heated in the range of (Tm-235) ° C. to (Tm-10) ° C. (eg, the range of (Tm-200) ° C. to (Tm-50) ° C.), The range of (Tm-225) ° C to (Tm-50) ° C (for example, the range of (Tm-190) ° C to (Tm-60) ° C), more preferably (Tm-215) ° C to (Tm-70). ) ° C. (for example, (Tm−180) ° C. to (Tm−70) ° C.).

  By heating in a specific temperature range as described above, water in the film (for example, the inside of the film or the surface of the film) is degassed and dried while suppressing the sudden generation of moisture from the film. It is possible to increase the kinetic energy of air existing on the surface and degas dry from the film surface.

  In addition, when performing deaeration drying under a heating independently, you may carry out on the conditions which do not contain the vacuum degree 1500Pa or less, for example, you may carry out under the atmospheric pressure (or normal pressure) which does not adjust a pressure. However, you may heat as needed under the conditions decompressed from atmospheric pressure (for example, exceeding 1500 Pa and less than 100,000 Pa, preferably about 3000 to 50000 Pa).

The time required for the degassing and drying step can be appropriately set according to various conditions such as the state of the thermoplastic liquid crystal polymer film in the thermoplastic liquid crystal polymer substructure, the degree of vacuum, and / or the heating temperature. The thermoplastic liquid crystal polymer film From the viewpoint of removing moisture and air from the whole, for example, each degassing drying step (under vacuum, under heating, under vacuum heating) is the same or different and takes 30 minutes or more, 40 minutes or more, or 50 minutes or more. It may be 6 hours or less, 4 hours or less, 3 hours or less, 2 hours or less, or 1.5 hours or less.
In addition, the time required for the degassing drying step may be appropriately set in consideration of, for example, the time when the moisture content of the thermoplastic liquid crystal polymer film falls within a predetermined range (for example, 380 ppm or less, 300 ppm or less, or 200 ppm or less). Good.

As described above, in the degassing drying step, when (a) degassing drying under vacuum and (b) degassing drying under heating are performed in combination, the thermal adhesiveness of the thermoplastic liquid crystal polymer substructure is increased. As long as it can be improved, the order of (a) deaeration drying under vacuum and (b) deaeration drying under heating may be any order, but preferably heating is performed as the first deaeration drying step. After performing deaeration drying below, deaeration drying under vacuum may be performed as a second deaeration drying step.
Specifically, for example, the deaeration drying step is a first deaeration drying step of performing deaeration drying by heating in a range of 80 ° C. to 300 ° C. for a predetermined time, and a vacuum degree of 1500 Pa or less and further predetermined And a second deaeration drying step for performing deaeration drying for a period of time. When performing these deaeration drying processes, it can carry out combining the conditions mentioned above suitably.

[Manufacturing Method According to First Embodiment]
A method for producing a thermoplastic liquid crystal polymer multilayer structure according to an embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic cross-sectional view for explaining a state before a shape fixing step in a method for producing a thermoplastic liquid crystal polymer multilayer structure according to an embodiment of the present invention, and FIG. 2 is a preliminary lamination in the shape fixing step. It is a schematic sectional drawing for demonstrating the state which applies a pressure to a body.

  As shown in FIG. 1, in the first embodiment of the present invention, the preliminary laminate 130 is heated from both the upper and lower surfaces by a hot press machine (preferably a vacuum hot press machine) 100 including an upper platen 110 and a lower platen 120. And pressurized. The preliminary laminated body 130 is composed of three thermoplastic liquid crystal polymer substructures 131, 132, and 133 in order from the top. In the thermoplastic liquid crystal polymer substructures 131 and 132, a conductor pattern is formed only on the top surface, and in the thermoplastic liquid crystal polymer substructure 133, a conductor pattern is formed on the top and bottom surfaces. Therefore, a conductor pattern is formed as a conductor layer on the upper and lower surfaces of the preliminary laminate 130.

  A first protective material 142 is disposed above the preliminary laminated body 130, and a second protective material 144 is disposed below the preliminary laminated body 130. Between the first protective material 142 and the upper platen 110, a first heat-resistant cushioning material 150 is disposed on the upper platen 110 side, and a first metal plate 152 is disposed on the first protective material 142 side. Established. On the other hand, a second heat-resistant cushion material 160 is disposed on the lower platen 120 side between the second protective material 144 and the lower platen 120, and the second metal plate 162 is disposed on the second protective material 144 side. Is disposed.

(Shape fixing process)
In the shape fixing step, the temperature of the hot press is increased to a first pressure below the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, and (I) the pre-laminate is placed through the protective material with the heat-resistant cushion material and Pressurized with a metal plate, (II) at the side of the preliminary laminate, the end of the protective material is sealed by pressurization of the heat-resistant cushion material, and (III) the protective material is all of the preliminary laminate. By wrapping the preliminary laminated body in a state of being in contact with the side surface, the shape of the preliminary laminated body is fixed so as to be the shape of a desired thermoplastic liquid crystal polymer multilayer structure.
For example, as shown in FIG. 2, first, according to pressurization from the hot press machine 100, the upper and lower platens 110, 120, the first and second heat resistant cushion materials 150, 160, the first and second metal plates 152, 162, and the first and second protective materials 142 and 144 sandwich the preliminary laminate 130 from above and below, so that the preliminary laminate 130 has the shape of the desired thermoplastic liquid crystal polymer multilayer structure. The pressure is increased to 1 and the pre-laminated body 130 is pressurized for a predetermined time. In this shape fixing step, the first and second heat-resistant cushion materials 150 and 160 sink on the upper and lower surfaces of the preliminary laminate 130 according to the thickness of the preliminary laminate 130 by the first pressure.

  As a result, the upper and lower surfaces of the preliminary laminate 130 are pressed by the first and second heat-resistant cushion materials 150 and 160 via the first and second protective materials 142 and 144, respectively. On the other hand, on the side of the preliminary laminate 130 where the preliminary laminate is not disposed, the first and second heat-resistant cushion materials are in a state where the first and second protective members 142 and 144 are in contact with each other. Pressurized by 150,160.

  As a result, the first and second protective materials 142 and 144 protect the portions that are in contact with the upper surface and the lower surface of the preliminary laminated body 130, respectively, and are in contact with all the side surfaces of the preliminary laminated body 130. The body 130 is wrapped and sealed with the first and second heat-resistant cushion materials 150 and 160 at the side of the pre-laminated body 130. And the shape of the preliminary | backup laminated body 130 is fixed also including a side surface by forming a seal structure with the 1st and 2nd protective material 142,144. As a result, the shape of the pre-laminated body 130 is fixed so as to be a desired shape of the thermoplastic liquid crystal polymer multilayer structure, and the thermoplastic liquid crystal polymer of the pre-laminated body 130 is pressed under pressure in a subsequent thermocompression bonding step. It can suppress flowing to the side.

  The first pressure applied to the pre-laminated body in the shape fixing step is not particularly limited as long as the shape of the heat-resistant cushion material is deformed to make the pre-laminated body a desired shape. 2-6 MPa may be sufficient, Preferably it is 2.5-5.5 MPa, More preferably, it is 3-5 MPa, More preferably, it may be 3.5-4.5 MPa.

The step of increasing the pressure to the first pressure may be performed at room temperature or less than the thermocompression bonding temperature in the thermocompression bonding step (for example, less than the glass transition temperature of the thermoplastic liquid crystal polymer to be fused). It may be in a heated state as appropriate. When heating, it may be heated before boosting. By heating, the pre-laminated body can be deaerated to improve the adhesiveness. In addition,
The peak temperature of tanD that appears when the temperature is raised from 25 ° C. to 220 ° C. at a rate of 3 ° C./min in dynamic viscoelasticity measurement (DMA) is defined as the glass transition temperature.

As described in the section of the deaeration drying process, the deaeration drying process may be performed on the preliminary laminate as part of the shape fixing process. In this case, the deaeration and drying conditions may be performed with reference to the conditions described in the above-described deaeration and drying process. From the viewpoint of degassing and drying the pre-laminated body, it is preferable to heat the pre-laminated body before increasing the pressure to the first pressure. For example, the heating temperature is not particularly limited as long as it is lower than the thermocompression bonding temperature in the thermocompression bonding process. For example, when the thermocompression bonding temperature is T ° C, it is (T-200) to (T-50) ° C. The temperature may be preferably (T-180) to (T-70) ° C, more preferably (T-160) to (T-90) ° C. Specifically, for example, it may be performed by heating in the range of 80 to 300 ° C, preferably in the range of 80 to 200 ° C, more preferably in the range of 100 to 200 ° C, still more preferably in the range of 115 to 200 ° C. It may be broken.
Further, the holding time at the heating temperature may be, for example, about 5 to 120 minutes, preferably about 5 to 60 minutes, and the moisture content of the thermoplastic liquid crystal polymer film is within a predetermined range (for example, 380 ppm or less, It may be set appropriately in view of the point of time when it becomes 300 ppm or less, or 200 ppm or less.

(Thermo-compression process)
In the thermocompression bonding step, the pressure is reduced from the first pressure, the temperature is raised to a thermocompression bonding temperature under a second pressure lower than the first pressure, and the adjacent thermoplastic liquid crystal polymer substructure is thermocompression bonded.
Specifically, after the shape of the preliminary laminated body is fixed to a desired shape by the shape fixing step, the pressure is then reduced and the pressure is reduced to a second pressure lower than the first pressure. Since the heat-resistant cushioning material has rebound resilience while being deformed, the shape of the preliminary laminated body can be maintained without changing the position with the protective material while closely approaching the shape of the preliminary laminated body. In particular, because the heat-resistant fiber cushion material used in the present invention is formed of fibers, even if the pressure is reduced from the first pressure to a predetermined pressure, the shape of the gap between the fibers is fixed as it is under pressure. can do. As a result, even if decompression is performed, the shape of the preliminary laminated body can be maintained without changing the positions of the heat-resistant cushioning material and the protective material already fixed.

  The second pressure is a range in which the shape of the deformed heat-resistant cushioning material or the protective material is maintained, the preliminary laminated body is fixed to a predetermined shape, and the thermoplastic liquid crystal polymer molecules do not flow excessively depending on the heating temperature. For example, it may be 0.5 to 3.5 MPa, preferably 1.0 to 3.0 MPa, and more preferably 1.5 to 2.5 MPa.

  The difference between the first pressure and the second pressure may be, for example, about 0.8 to 2.5 MPa, and preferably about 1.3 to 2.3 MPa.

  For example, as shown in FIG. 2, in the thermocompression bonding step, the temperature of the preliminary laminate 130 is increased to the thermocompression bonding temperature under the second pressure, and is held for a predetermined time, thereby adjoining the thermoplastic liquid crystal polymer. The substructures 131, 132, 133 are thermocompression bonded together.

  By disposing the first and second metal plates 152 and 162, the pattern derived from the first and second heat-resistant cushion materials 150 and 160 is formed on the surface of the pre-laminated body 130 in the thermocompression bonding step. Can be prevented.

  On the other hand, the conductor pattern formed on the upper and lower surfaces of the pre-laminated body 130 is protected by the protective materials 142 and 144 during thermocompression bonding, so that the conductor pattern does not shift even when pressure is applied from the metal plate. Thermocompression bonding can be performed. As such a protective material, a multilayer composite material that can be deformed according to the shape of the conductor pattern is preferable.

  The thermocompression bonding temperature is not limited as long as any one of adjacent units can be fused between the thermoplastic liquid crystal polymers forming the thermoplastic liquid crystal polymer substructure.

  For example, the thermocompression bonding temperature may be determined after grasping the heat fusion temperature of the thermoplastic liquid crystal polymer substructure in advance. For example, when the melting point of the thermoplastic liquid crystal polymer film to be fused is (Tm), the thermocompression bonding temperature may be, for example, in the range of (Tm−20) to (Tm + 20) ° C., preferably (Tm− 15)-(Tm + 5) degree C degree may be sufficient. From the viewpoint of performing reliable fusion, the thermoplastic liquid crystal polymer film to be fused may be a thermoplastic liquid crystal polymer film having the highest melting point in the preliminary laminate.

  The time for holding at the thermocompression bonding temperature may be, for example, about 1 to 30 minutes, preferably about 1 to 15 minutes.

  After the thermocompression bonding step, the temperature is decreased and the pressure is released, and then the thermoplastic liquid crystal polymer multilayer structure is removed from the protective material to obtain a thermoplastic liquid crystal polymer multilayer structure having a desired shape (laminated structure). it can. Further, the heat resistant cushioning material can recover the resilience and maintain the cushioning property by releasing the pressure, so that the heat resistant cushioning material can be used a plurality of times. In particular, in the heat resistant fiber cushion material, since the space between the fibers can be increased and the cushioning property can be maintained, the heat resistant cushion material can be repeatedly used a plurality of times (particularly 10 times or more).

[Manufacturing Method According to Second Embodiment]
In FIG. 3, the schematic sectional drawing for demonstrating the state before a shape fixing process is shown about the manufacturing method which concerns on 2nd embodiment. 3, members that are the same as or correspond to those in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted. Compared with the manufacturing method according to the first embodiment, the manufacturing method according to the second embodiment basically includes the same steps, and the description of the overlapping steps will not be repeated.

  As shown in FIG. 3, in the second embodiment of the present invention, the upper and lower platens 110 and 120, the first and second heat-resistant cushion materials 150 and 160, and the first according to the pressure from the hot press machine 200. The pre-lamination body 230 is heated and pressurized from above and below by the second metal plates 152 and 162 and the first and second protective members 242 and 244. The preliminary laminated body 230 includes three thermoplastic liquid crystal polymer substructures 231, 232, and 233 in order from the top. The thermoplastic liquid crystal polymer substructure 231 is a single thermoplastic liquid crystal polymer layer, and the thermoplastic liquid crystal polymer substructures 232 and 233 have a conductor pattern formed only on the upper surface of the thermoplastic liquid crystal polymer layer. Therefore, the preliminary laminated body 230 has no conductor pattern on the upper and lower surfaces thereof.

  A first protective material 242 is disposed above the preliminary laminated body 230, and a second protective material 244 is disposed below the preliminary laminated body 230. Between the first protective material 242 and the upper platen 110, a first heat-resistant cushioning material 150 is disposed on the upper platen 110 side, and a first metal plate 152 is disposed on the first protective material 242 side. Established. On the other hand, a second heat-resistant cushion material 160 is disposed on the lower platen 120 side between the second protective material 244 and the lower platen 120, and the second metal plate 162 is disposed on the second protective material 244 side. Is disposed.

(Shape fixing process)
The shape fixing step is performed in substantially the same manner as in FIG. 2 except that the first and second protective members 242 and 244 are used instead of the first and second protective members 142 and 144 in FIG. In the second embodiment, the first and second protective members 242 and 244 surround the upper and lower surfaces of the preliminary laminated body 230, respectively, and the first and second protection members protrude from the side of the preliminary laminated body 230. The ends of the materials 242 and 244 are pressed from above and below by the first and second heat resistant cushion materials 150 and 160.

(Thermo-compression process)
After the shape of the preliminary laminated body 230 is fixed to a desired shape by the shape fixing step, the pressure is then reduced and the pressure is reduced to a second pressure lower than the first pressure. Then, under the second pressure, the temperature of the preliminary laminated body 230 is raised to the thermocompression bonding temperature and maintained for a predetermined time, so that the adjacent thermoplastic liquid crystal polymer substructures 231, 232, 233 are thermocompression bonded. The

  Since no conductive patterns are formed on the upper and lower surfaces of the preliminary laminated body 230, the heat does not affect the shapes of the upper and lower surfaces of the preliminary laminated body 230 even when pressure is applied from a metal plate during thermocompression bonding. Crimping can be performed. In such a case, a single layer sheet may be used as the first and second protective members 242 and 244 in order to simplify the manufacturing process.

  When a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure, the protective material in contact with the surface on which the conductor pattern is formed is deformed according to the shape of the conductor pattern. The possible multilayer composite material may be sufficient and the protective material which touches the surface in which the said conductor pattern is not formed may be a single layer sheet.

[Manufacturing Method According to Third Embodiment]
A method for producing a thermoplastic liquid crystal polymer multilayer structure according to another embodiment of the present invention will be described below with reference to FIGS. In the present invention, since at least one of the upper and lower surfaces of the pre-laminated body may be provided with a protective material, a metal plate, and a heat-resistant cushion material in order from the side closest to the surface of the pre-laminated body, FIG. In No. 5, these are arranged on one side of the preliminary laminate. In the figure, for ease of understanding, the metal plate and heat-resistant cushioning material are placed only above the pre-laminated body, but naturally the metal plate and heat-resistant cushioning material are placed only below the pre-laminated body. May be.

  FIG. 4 is a schematic cross-sectional view for explaining the state before the shape fixing step in the method for producing a thermoplastic liquid crystal polymer multilayer structure according to the third embodiment of the present invention, and FIG. It is a schematic sectional drawing for demonstrating the state which applies a pressure to a preliminary | backup laminated body. 4 and 5, members that are the same as or correspond to those in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted. The manufacturing method according to the third embodiment basically includes the same steps as those of the manufacturing method according to the first embodiment, and the description of the overlapping steps will not be repeated.

  As shown in FIG. 4, in the third embodiment of the present invention, the preliminary laminated body 130 is heated and pressurized from both the upper and lower surfaces by a hot press machine 300 including an upper platen 110 and a lower platen 120. The preliminary laminated body 130 is composed of three thermoplastic liquid crystal polymer substructures 131, 132, and 133 in order from the top. In the thermoplastic liquid crystal polymer substructures 131 and 132, a conductor pattern is formed only on the top surface, and in the thermoplastic liquid crystal polymer substructure 133, a conductor pattern is formed on the top and bottom surfaces. Therefore, conductor patterns are formed as conductor layers on the upper and lower surfaces of the preliminary laminate.

  A first protective material 142 is disposed above the preliminary laminated body 130, and a second protective material 144 is disposed below the preliminary laminated body 130. Between the first protective material 142 and the upper platen 110, a first heat-resistant cushioning material 150 is disposed on the upper platen 110 side, and a first metal plate 152 is disposed on the first protective material 142 side. Established. On the other hand, nothing is disposed between the second protective material 144 and the lower platen 120, and the second protective material 144 directly contacts the lower platen 120 during pressurization.

  In the present invention, at least one of the upper and lower surfaces of the preliminary laminate may be provided with a protective material, a metal plate, and a heat-resistant cushion material in order from the side closer to the surface of the preliminary laminate. Even with the heat resistant cushioning material 150 alone, sufficient subsidence with respect to the pre-lamination body can be achieved with respect to the pressure applied by the upper and lower platens, and therefore the arrangement of the metal plate and the heat resistant cushioning material is omitted on the lower platen side. .

(Shape fixing process)
As shown in FIG. 5, the heat press machine 300 including the upper platen 110 and the lower platen 120 causes the first heat-resistant cushioning material 150, the first metal plate 152, and the first protective material 142 from the upper surface to be viewed from the lower surface. The pre-laminated body 130 is sandwiched between the upper and lower surfaces by the second protective material 144, and the pre-laminated body 130 is pressurized to the first pressure so as to have a desired thermoplastic liquid crystal polymer multilayer structure, During this time, the pre-laminated body 130 is pressurized. In the shape fixing step, the first heat-resistant cushion material 150 is deformed by the first pressure.

  The first and second protective materials 142 and 144 respectively surround the upper and lower surfaces of the preliminary laminated body 130 and the first and second protective materials 142 and 144 that protrude to the side of the preliminary laminated body 130. The end is further pressed from above and below by the first heat-resistant cushioning material 150 and the lower platen 120. In this case, the seal structure of the first and second protective members 142 and 144 is formed by pressing the first heat-resistant cushion material 150 against the lower platen 120. With this sealing structure, the shape of the preliminary laminated body 130 is fixed including the side surface, and the thermoplastic liquid crystal polymer of the preliminary laminated body 130 is prevented from flowing laterally under pressure in a temperature raising process performed later. it can.

  On the other hand, when the first metal plate 152 is disposed, even if pressure is applied to the shape fixing step so that the first heat-resistant cushion material 150 is deformed, a pattern derived from the heat-resistant cushion material 150, etc. Can be prevented from being reflected on the surface of the preliminary laminate 130.

  Further, following the deformation of the first heat-resistant cushioning material 150, the first and second protective materials 142 and 144 are deformed so that the end portions thereof wrap around the side surface of the preliminary laminated body 130. As a result, the side surface of the preliminary laminated body 130 is wrapped by the protective materials 142 and 144 and the heat-resistant cushioning material 150, and the shape is fixed so that the preliminary laminated body 130 has the shape of a desired thermoplastic liquid crystal polymer multilayer structure. can do.

  The step of increasing the pressure to the first pressure may be performed at room temperature or may be appropriately heated as long as it is lower than the thermocompression bonding temperature of the thermoplastic liquid crystal polymer. When heating, it may be heated before boosting.

(Thermo-compression process)
After fixing the shape of the preliminary laminated body 130 to a desired shape by the shape fixing step, the pressure is then reduced to a second pressure lower than the first pressure. In the thermocompression bonding step, under the second pressure, the temperature of the preliminary laminated body 130 is raised to the thermocompression bonding temperature and held for a predetermined time, so that the adjacent thermoplastic liquid crystal polymer substructures 131, 132, and 133 are adjacent to each other. Thermocompression bonded. At the time of thermocompression bonding, the conductor pattern formed on the upper and lower surfaces of the pre-laminated body 130 is protected by the protective materials 142 and 144, so that the conductor pattern does not shift even when pressure is applied from the metal plate. It can be performed.

  After the thermocompression bonding step, the temperature is decreased and the pressure is released, and then the thermoplastic liquid crystal polymer multilayer structure is removed from the protective material to obtain a thermoplastic liquid crystal polymer multilayer structure having a desired shape (laminated structure). it can.

  In addition to the representative first, second, and third embodiments described above, various embodiments may be included based on the concept of the present invention. The points common to the embodiments will be described below.

(Heat resistant cushioning material)
The heat-resistant cushion material is not particularly limited as long as it has rebound resilience while having deformability, and preferable heat-resistant cushion materials include heat-resistant cushion sheets and heat-resistant fiber cushion materials.

From the viewpoint of having rebound resilience while having deformability, the basis weight of the heat-resistant cushioning material can be appropriately selected according to the type of the constituent material, but from the viewpoint of having good rebound resilience, for example, 100 -3000 g / m < ² > may be sufficient, Preferably it is 150-2500 g / m < ² >, More preferably, 300-2000 g / m < ² > may be sufficient. Further, the cushioning property may be increased by stacking several of these heat-resistant cushioning materials.

  For example, the heat resistant fiber cushion material is a cushion material formed of a heat resistant fiber assembly. The heat-resistant fiber assembly may be formed of, for example, a heat-resistant fiber that can be used at a thermocompression bonding temperature, for example, a heat-resistant fiber having a thermal deformation temperature equal to or higher than the thermocompression bonding temperature. It can be set according to the pressure bonding temperature. For example, as a standard of heat-resistant fiber, a fiber that can be used as a cushioning material at 260 ° C. may be used.

Examples of heat resistant fibers include heat resistant organic fibers, metal fibers, and inorganic fibers. More specifically, the heat-resistant organic fiber may be a fiber having a melting point or a thermal decomposition temperature of 260 ° C. or higher, such as an aramid fiber (meta-aramid fiber, para-aramid fiber), semi-aromatic polyamide. system fibers (e.g., polyamide (PA9C) fibers constituted by the _{C 9} aliphatic diamine units and aromatic dicarboxylic acid units), polyimide (PI) fibers, polyphenylene sulfide (PPS) fibers, polyetheretherketone (PEEK) fibers , Polybenzimidazole (PBI) fiber, polyparaphenylene benzoxazole (PBO) fiber, and novoloid fiber. Examples of the metal fiber include stainless steel fiber, copper fiber, nickel fiber, and aluminum fiber. Examples of the inorganic fiber include glass fiber. These fibers may be used alone or in combination of two or more as the fibers constituting the heat resistant fiber cushion material.

  The fiber aggregate is not particularly limited as long as it is a fiber aggregate exhibiting cushioning properties, and may be a woven fabric, a knitted fabric, a mechanically bonded nonwoven fabric (for example, needle punched nonwoven fabric), a felt, a web, or the like. From this point of view, a nonwoven fabric, felt, a plate-like molded product of metal fiber or inorganic fiber is preferable, and a metal fiber nonwoven fabric or an organic fiber nonwoven fabric having a melting point or a thermal decomposition temperature of 260 ° C. or more is more preferable.

  The fiber diameter of the heat resistant fiber cushion material may be, for example, 1 to 30 μm, preferably 2 to 20 μm, and more preferably 5 to 18 μm.

  The heat-resistant cushion sheet is a cushion material formed of a heat-resistant material other than fibers. Examples of heat resistant materials other than fibers include heat resistant resins and heat resistant rubbers. Examples of the heat resistant cushion sheet include a heat resistant cushion sheet having a Shore hardness of about A50 to A95, for example, “Super Tempex” manufactured by Seibu Polymer Kasei Co., Ltd., “Sylbest” manufactured by Kinyo Co., Ltd., and the like.

  According to the manufacturing process of the present invention, the heat-resistant cushioning material can be used repeatedly, and the manufacturing cost can be reduced.

In addition, the vertical length (C _L ) and the horizontal side length (C _W ) of the heat-resistant cushion material are the same as the vertical length (P _L ) and the horizontal side length of the preliminary laminate. It is preferable to have the following relationship with respect to (P _W ).
P _L + 1 ≦ C _L ≦ P _L +10 (unit: cm) and P _W + 1 ≦ C _W ≦ P _W +10 (unit: cm)
More preferably, it has the following relationship.
P _L + 2 ≦ C _L ≦ P _L +8 (unit: cm) and P _W + 2 ≦ C _W ≦ P _W +8 (unit: cm)

  For example, the heat resistant cushioning material may have a thickness of about 0.5 to 20 mm, preferably about 1 to 18 mm, and more preferably about 1.5 to 16 mm.

  Moreover, when the total thickness after lamination | stacking of the preliminary laminated body laminated | stacked by hot press is set to D (unit: mm), the thickness of a heat-resistant cushioning material is (D + 0.5)-as total thickness in a hot press machine. It may be about (D + 20) mm, preferably about (D + 1) to (D + 15) mm, more preferably about (D + 2) to (D + 10) mm.

(Metal plate)
The metal plate is disposed in order to prevent the shape derived from the heat-resistant cushion material from appearing on the surface of the thermoplastic liquid crystal polymer multilayer structure. Therefore, when the heat resistant cushion material is not provided, the metal plate may not be provided.
As a metal which comprises a metal plate, the well-known or usual metal material with high compression resistance can be used, for example, Preferably it is stainless steel or copper.

  For example, the metal plate may have a thickness of about 0.1 to 2 mm, preferably about 0.2 to 0.8 mm, and more preferably about 0.3 to 0.6 mm.

Further, the vertical length (M _L ) and the horizontal side length (M _W ) of the metal plate are the vertical length (C _L ) and the horizontal side length of the heat-resistant cushioning material. It may have the following relationship with respect to (C _W ), the length in the vertical direction (P _L ) and the length of the side in the horizontal direction (P _W ).
P _L −1.0 ≦ M _L ≦ P _L (unit: cm)
P _W −1.0 ≦ M _W ≦ P _W (unit: cm)
C _L −11 ≦ M _L ≦ C _L −1.2 (unit: cm) and C _W −11 ≦ M _W ≦ C _W −1.2 (unit: cm)

Preferably, it may have the following relationship.
P _L −0.8 ≦ M _L ≦ P _L (unit: cm)
P _W −0.8 ≦ M _W ≦ P _W (unit: cm)
C _L −8 ≦ M _L ≦ C _L −0.5 (unit: cm) and C _W −8 ≦ M _W ≦ C _W −0.5 (unit: cm)

(Protective layer)
In the thermocompression bonding step, the protective material is used to protect the surface of the preliminary laminate by wrapping the surface of the preliminary laminate, that is, the upper and lower surfaces and the side surfaces. Examples of the protective material include a composite material of a metal foil such as a polytetrafluoroethylene sheet, a polyimide sheet, and an aluminum foil and a heat-resistant polymer sheet.

  For example, the protective material may be properly used depending on the state of the surface of the preliminary laminate, and when the conductor pattern is formed on the outermost surface of the preliminary laminate, the protective material in contact with the outermost surface is It may be a multilayer composite material that can be deformed according to the shape of the conductor pattern.

  On the other hand, when the conductor pattern is formed on the outermost surface of the preliminary laminate, the protective material in contact with the outermost surface may be a multilayer composite material that can be deformed according to the shape of the conductor pattern, From the simplicity of work, it may be a simple single layer sheet.

  For example, as a multilayer composite material, a first metal foil (preferably an aluminum foil), a pair of high-density polyethylene sheets whose MD directions are orthogonal to each other, a second metal foil (preferably an aluminum foil), and a low A multilayer composite material formed of a frictional film is particularly preferably used.

  As the high density polyethylene sheet, a known or commonly used HDPE sheet can be used. For example, the viscosity average molecular weight of the high density polyethylene is, for example, 20,000 to 500,000, preferably about 50,000 to 300,000, and more preferably 100,000. About 200,000 may be sufficient.

  Examples of the low friction film include a film having a low coefficient of friction defined by JIS K 7125 having a low coefficient of friction of 0.30 or less (preferably about 0.05 to 0.25). Examples thereof include an ultrahigh molecular weight polyethylene film and a polytetrafluoroethylene film.

  For example, the ultrahigh molecular weight polyethylene film has a static friction coefficient of about 0.10 to 0.25, and the viscosity average molecular weight is, for example, 1 million or more, preferably about 2 million to 7 million, and more preferably 3 million to 600. It may be about 10,000. In addition, the measuring method of the intrinsic viscosity number used for calculation of a viscosity average molecular weight can be measured based on JISK7367-3: 1999.

Further, the polytetrafluoroethylene film has a static friction coefficient of about 0.08 to 0.12, and its melt viscosity at 380 ° C. is 10 ¹⁰ poise or more, preferably 10 ¹⁰ to 10 ¹¹ poise. May be.

(Thermoplastic liquid crystal polymer multilayer structure)
In the production method of the present invention, the polymer can be prevented from flowing and crushing the conductor pattern in the thermocompression bonding process, and unintentional displacement between layers can be prevented, and excellent integration between the thermoplastic liquid crystal polymer substructures is excellent. A thermoplastic liquid crystal polymer multilayer structure can be obtained.

  As the thermoplastic liquid crystal polymer substructure, various shapes can be used as long as they are formed from a thermoplastic liquid crystal polymer and a plurality of thermoplastic liquid crystal polymer substructures can be integrated by thermocompression bonding. Preferably, in the thermoplastic liquid crystal polymer multilayer structure, the thermoplastic liquid crystal polymer substructure includes (i) a thermoplastic liquid crystal polymer layer alone (L), and (ii) a thermoplastic liquid crystal polymer layer having a conductor layer on one surface ( CL), and (iii) can be selected from the group consisting of a thermoplastic liquid crystal polymer layer (CLC) having a conductor layer on both sides. Here, examples of the conductor layer include a conductor pattern, a conductor foil, a conductor film, and the like, and a desired shape may be appropriately formed on these conductor layers as necessary.

  The thermoplastic liquid crystal polymer multilayer structure may have three or more conductor layers. Moreover, according to a use, you may have a conductor layer 5 layers or more, 7 layers or more. The upper limit of the conductor layer can be appropriately set according to the application, and may be, for example, about 20 layers.

  In addition, the thermoplastic liquid crystal polymer films constituting the thermoplastic liquid crystal polymer multilayer structure may have the same or different melting points. If they are different, the temperature difference between the film with the lowest melting point and the film with the highest melting point exceeds 0 ° C and is 100 ° C or less, preferably 10 ° C or more and 90 ° C or less, more preferably 20 ° C or more. 80 degrees C or less may be sufficient.

  Further, the thermoplastic liquid crystal polymer films constituting the thermoplastic liquid crystal polymer multilayer structure may have the same thickness or different thicknesses. If they are different, the difference between the thickest film and the thinnest film may be more than 0 μm and 50 μm or less, preferably 10 μm or more and 40 μm or less, more preferably 20 μm or more and 30 μm or less.

  The manufacturing method of the thermoplastic liquid crystal polymer multilayer structure may include processing steps known to those skilled in the art, such as blind vias, perforation for through holes, and plating treatment, if necessary.

  For example, the thermoplastic liquid crystal polymer multilayer structure can be effectively used as a part used in the electric / electronic field, office equipment / precision equipment field, etc., for example, a circuit board (particularly, a millimeter wave radar board), etc. As useful.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited at all by this Example. In the following examples and comparative examples, various physical properties were measured by the following methods.

[Melting point]
Using DSC (manufactured by TA Instruments, “Q2000”), about 5 mg of sample, the temperature was raised from room temperature to the temperature at which the sample was polymerized at a rate of 20 ° C. per minute, and kept at that temperature for 2 minutes. The temperature was cooled to 25 ° C. at a rate of 20 ° C., held at 25 ° C. for 2 minutes, and the endothermic peak temperature when the temperature was raised again at a rate of 20 ° C. per minute was taken as the melting point.

[Transfer of pattern to thermoplastic liquid crystal polymer multilayer structure (LCP multilayer structure)]
About the surface of the thermoplastic liquid crystal polymer multilayer structure obtained after the thermocompression bonding step, whether or not the pattern of the heat-resistant cushion material was transferred by visual inspection was evaluated based on the following criteria.
○: The transferred pattern is not confirmed on the surface of the thermoplastic liquid crystal polymer multilayer structure.
X: The transferred pattern was confirmed on the surface of the thermoplastic liquid crystal polymer multilayer structure.

[Cushion material shape retention]
The shape retention of the heat resistant cushion material after the thermocompression bonding process was evaluated according to the following criteria.
○: The heat-resistant cushioning material retained its shape and was not fused to the platen, and the cushioning property was restored again after the pressure was released.
X: The heat-resistant cushioning material could not retain its shape and was fused to the platen, and / or the cushioning property was not recovered after the pressure was released.

[Flow and collapse of thermoplastic liquid crystal polymer multilayer structure (LCP multilayer structure)]
The flow and crushing of the thermoplastic liquid crystal polymer multilayer structure obtained after the thermocompression bonding step was visually evaluated according to the following criteria.
○: The thermoplastic liquid crystal polymer multilayer structure was bonded without shifting in each layer, the conductor pattern on the surface was not crushed, and the resin did not flow laterally on the side surfaces.
×: The thermoplastic liquid crystal polymer multilayer structure has at least one of the following phenomena: the layers are bonded in a shifted state, the conductor pattern on the surface is crushed, or the resin is flowing laterally on the side surface. One was occurring.

(Reference Example 1)
A copper foil of the same size on both sides of a thermoplastic liquid crystal polymer film having a melting point of 310 ° C. (manufactured by Kuraray Co., Ltd., “BEXTER”, 30 cm long × 40 cm wide × 18 μm thick) (manufactured by Fukuda Metal Foil Powder Co., Ltd., “ CF-H9A-DS-HD2-12 ") was superposed and subjected to thermocompression bonding at 290 ° C. and 2 MPa by a vacuum batch press (“ VH2-1600 ”manufactured by Kitagawa Seiki Co., Ltd.) to produce a double-sided copper-clad plate. . Thereafter, a conductor pattern was formed by etching to obtain a thermoplastic liquid crystal polymer substructure in which the conductor pattern was formed on both surfaces.

(Reference Example 2)
A thermoplastic liquid crystal polymer film having a melting point of 310 ° C. (manufactured by Kuraray Co., Ltd., “BEXTER”, 30 cm long × 40 cm wide × 18 μm thick) on one side of the same size copper foil (Fukuda Metal Foil Powder Co., Ltd.) “CF-H9A-DS-HD2-12”) is superimposed and a single-sided copper-clad plate is produced by thermocompression bonding at 290 ° C. and 2 MPa by a vacuum batch press (“VH2-1600” manufactured by Kitagawa Seiki Co., Ltd.). did. Thereafter, a conductor pattern was formed by etching to obtain a thermoplastic liquid crystal polymer substructure in which the conductor pattern was formed on one surface.

[Example 1]
In the hot press machine, as shown in FIG. 1, a heat-resistant cushioning material, a metal plate, and a protective material are arranged in order from the upper platen of the hot-pressing machine, and the heat-resistant cushioning material in order from the lower platen of the hot press machine. In addition, a metal plate and a protective material were disposed, and the preliminary laminated body was aligned and disposed between these protective materials. The preliminary laminate is composed of the thermoplastic liquid crystal polymer substructures obtained in Reference Examples 1 and 2 as shown in FIG. 1, and is composed of three thermoplastic liquid crystal polymer substructures. The protective material and the pre-laminated body have the same center point in the thickness direction.

In addition, a stainless steel web (manufactured by Nippon Seisen Co., Ltd., “Naslon web”, fiber diameter 8 μm, basis weight 1800 g / m ² , length 33 cm × width 43 cm × thickness 15 mm) is used as a heat-resistant cushion material, and metal A SUS plate (length 30 cm × width 40 cm × thickness 0.4 mm) was used as the plate. Furthermore, as a protective material, from the preliminary laminate toward the platen side, a polytetrafluoroethylene film (thickness 30 μm, static friction coefficient 0.12), a first aluminum foil (thickness 50 μm), a first high-density polyethylene film (Okura) “HD film” manufactured by Kogyo Co., Ltd., thickness 50 μm), second high-density polyethylene film in the MD direction orthogonal to the first high-density polyethylene film (manufactured by Okura Kogyo Co., Ltd., “HD film” , Thickness 50 μm, melt flow index 0.05), and second aluminum foil (thickness 50 μm). The size of the protective material is 34 cm long × 44 cm wide.

First, a shape fixing step was performed using a vacuum batch press (“VH2-1600” manufactured by Kitagawa Seiki Co., Ltd.) as a hot press. Specifically, the upper and lower surfaces of the preliminary laminate were pressurized at 4 MPa for 10 minutes at a vacuum of 4 torr and 160 ° C. By this operation, as shown in FIG. 2, the side surface of the pre-laminated body was wrapped with the protective material and the heat-resistant cushion material, and the protective material was sealed with the heat-resistant cushion material on the side of the pre-laminated body.
Next, the pressure applied to the pre-laminated body was reduced to 2 MPa, the temperature was raised to 300 ° C., held for 30 minutes, the pre-laminated body was subjected to thermocompression bonding, cooled to room temperature, and then the pressure was released. A thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 2]
As a heat-resistant cushioning material, a stainless steel felt (manufactured by Nippon Seisen Co., Ltd., “Naslon Felt”, fiber diameter 8 μm, basis weight 1500 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. In the same manner as in Example 1, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 3]
Example 1 except that para-aramid fiber needle punched non-woven fabric (manufactured by Ichikawa Co., Ltd., “ACE BOARD”, basis weight 1300 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. In the same manner as above, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 4]
As a heat-resistant cushioning material, _{C 9} aliphatic diamine units and composed of a terephthalic acid unit semi-aromatic polyamide resin (manufactured by Kuraray Co., Ltd., "GENESTAR PA9T") meltblown nonwoven (basis weight 800 g / ^{m 2} of the vertical 33cm A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1 except that × horizontal 43 cm × thickness 3 mm) was used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 1]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Example 1 except that a non-woven polyester nonwoven fabric (weight per unit area: 4400 g / m ² , length 33 cm × width 43 cm × thickness 20 mm) was used as the cushion material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 5]
A thermoplastic liquid crystal polymer film having a melting point of 310 ° C. (manufactured by Kuraray Co., Ltd., “BEXTER”, 30 cm long × 40 cm wide × 18 μm thick) and the thermoplastic liquid crystal polymer substructure obtained in Reference Example 2 are shown in FIG. In combination, a preliminary laminate was formed with three thermoplastic liquid crystal polymer substructures.

  A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1 except that a polytetrafluoroethylene sheet was used as a protective material for the preliminary laminate. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 6]
As a heat-resistant cushioning material, a stainless steel felt (manufactured by Nippon Seisen Co., Ltd., “Naslon Felt”, fiber diameter 8 μm, basis weight 1500 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. In the same manner as in Example 5, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 7]
Example 5 except that para-aramid fiber needle punched non-woven fabric (“IC board”, basis weight 1300 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) was used as the heat-resistant cushion material. In the same manner as above, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 8]
As a heat-resistant cushioning material, _{C 9} aliphatic diamine units and composed of a terephthalic acid unit semi-aromatic polyamide resin (manufactured by Kuraray Co., Ltd., "GENESTAR PA9T") meltblown nonwoven (basis weight 800 g / ^{m 2} of the vertical 33cm A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 5 except that × horizontal 43 cm × thickness 3 mm) was used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 2]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Example 5 except that a polyester non-woven fabric (weight per unit area: 4400 g / m ² , length 33 cm × width 43 cm × thickness 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 9]
In the hot press machine, as shown in FIG. 4, a heat-resistant cushioning material, a metal plate, and a protective material are arranged in order from the upper platen of the hot press machine, and between the lower platen and the preliminary laminate of the hot press machine. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1 except that only the protective material was provided. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 10]
As a heat-resistant cushioning material, a stainless steel felt (manufactured by Nippon Seisen Co., Ltd., “Naslon Felt”, fiber diameter 8 μm, basis weight 1500 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. In the same manner as in Example 9, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 11]
Example 9 except that para-aramid fiber needle punched non-woven fabric (manufactured by Ichikawa Co., Ltd., “ACE board”, basis weight 1300 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushioning material. In the same manner as above, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 12]
As a heat-resistant cushioning material, a melt blown nonwoven fabric (weight per unit area: 800 g / m ² , length 33 cm × width) of a semi-aromatic polyamide-based resin (Genare PA9T manufactured by Kuraray Co., Ltd.) composed of C ₉ aliphatic diamine units and terephthalic acid units A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9 except that 43 cm × thickness 3 mm) was used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Example 13]
The thermoplastic liquid crystal polymer substructures obtained in Reference Examples 1 and 2 were degassed and dried at 200 ° C. for 60 minutes using a hot air oven to reduce the moisture content to 100 ppm or less, and then a preliminary laminate was formed and fixed in shape. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9 except that the steps were performed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.
In addition, the thermoplastic liquid crystal polymer multilayer structure obtained through the degassing drying step has high adhesiveness between the respective layers, and it was difficult to peel off between adjacent thermoplastic liquid crystal polymer substructures.

[Example 14]
The thermoplastic liquid crystal polymer substructure obtained in Reference Examples 1 and 2 was degassed and dried for 60 minutes at 200 ° C. and a vacuum degree of 1500 Pa or less using a vacuum oven, and the moisture content was adjusted to 100 ppm or less. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 9 except that the shape fixing step was performed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.
In addition, the thermoplastic liquid crystal polymer multilayer structure obtained through the degassing drying step has high adhesiveness between the respective layers, and it was difficult to peel off between adjacent thermoplastic liquid crystal polymer substructures.

[Comparative Example 3]
A thermoplastic liquid crystal polymer multilayer structure was used in the same manner as in Example 9 except that a non-woven polyester nonwoven fabric (weight per unit area: 4400 g / m ² , length 33 cm × width 43 cm × thickness 20 mm) was used as the cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 4]
In the heat press machine 400, as shown in FIG. 6, a heat-resistant cushioning material 150 and a protective material 142 are disposed in order from the upper platen 110 of the heat press machine without using a metal plate. A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Example 1 except that the heat-resistant cushion material 160 and the protective material 144 were disposed in order from the platen. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 5]
As a heat-resistant cushioning material, a stainless steel felt (manufactured by Nippon Seisen Co., Ltd., “Naslon Felt”, fiber diameter 8 μm, basis weight 1500 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. In the same manner as in Comparative Example 4, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 6]
Comparative Example 4 except that para-aramid fiber needle punched nonwoven fabric (“IC board”, basis weight 1300 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used as the heat-resistant cushion material. In the same manner as above, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 7]
As a heat-resistant cushioning material, _{C 9} aliphatic diamine units and composed of a terephthalic acid unit semi-aromatic polyamide resin (manufactured by Kuraray Co., Ltd., "GENESTAR PA9T") meltblown nonwoven (basis weight 800 g / ^{m 2} of the vertical 33cm A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Comparative Example 4 except that (horizontal 43 cm × thickness 3 mm) was used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 8]
A thermoplastic liquid crystal polymer multilayer structure is produced in the same manner as in Comparative Example 4 except that a non-woven polyester nonwoven fabric (weight per unit area: 4400 g / m ² , length 33 cm × width 43 cm × thickness 20 mm) is used as a cushioning material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 9]
In the hot press machine 500, as shown in FIG. 7, heat was applied in the same manner as in Example 1 except that the size of the metal plate was increased and a SUS plate (length 31 cm × width 41 cm × thickness 0.4 mm) was used. A heat-resistant cushioning material 150, a metal plate 552, and a protective material 142 are arranged in order from the upper platen 110 of the press 500, and a heat-resistant cushioning material 160, a metal plate 562, and a protective material are arranged in order from the lower platen of the hot press. A thermoplastic liquid crystal polymer multilayer structure was obtained except that 144 was disposed. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 10]
As a heat-resistant cushioning material, a stainless steel felt (manufactured by Nippon Seisen Co., Ltd., “Naslon Felt”, fiber diameter 8 μm, basis weight 1500 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) is used. In the same manner as in Comparative Example 9, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 11]
Comparative Example 9 except that para-aramid fiber needle punched nonwoven fabric ("IC board", basis weight 1300 g / m ² , length 33 cm × width 43 cm × thickness 7 mm) was used as the heat-resistant cushion material. In the same manner as above, a thermoplastic liquid crystal polymer multilayer structure was obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 12]
As a heat-resistant cushioning material, _{C 9} aliphatic diamine units and composed of a terephthalic acid unit semi-aromatic polyamide resin (manufactured by Kuraray Co., Ltd., "GENESTAR PA9T") meltblown nonwoven (basis weight 800 g / ^{m 2} of the vertical 33cm A thermoplastic liquid crystal polymer multilayer structure was obtained in the same manner as in Comparative Example 9 except that (width 43 cm × thickness 3 mm) was used. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

[Comparative Example 13]
A thermoplastic liquid crystal polymer multilayer structure was prepared in the same manner as in Comparative Example 9 except that a non-woven polyester nonwoven fabric (weight per unit area: 4400 g / m ² , length: 33 cm × width: 43 cm × thickness: 20 mm) was used as the cushion material. Obtained. Table 7 shows the evaluation of the obtained thermoplastic liquid crystal polymer multilayer structure.

  In Examples 1-8, since the heat-resistant cushioning material was combined with the metal plate and thermocompression bonding was performed in a state where the protective material was in contact with the side surface of the preliminary laminate, the obtained thermoplastic liquid crystal polymer multilayer structure had heat resistance The pattern derived from the cushion material was not transferred, and the flow of the thermoplastic liquid crystal polymer and the collapse of the conductor pattern were not confirmed. Further, the heat-resistant cushioning material could retain its shape in the thermocompression bonding process, and no fusion to the platen occurred. Moreover, after releasing the pressure, the cushioning property was recovered again. Therefore, it is estimated that the heat resistant cushioning material can withstand repeated use.

  Moreover, also in Examples 9 to 14 in which the heat-resistant cushion material is disposed only on one surface of the pre-laminated body, the obtained thermoplastic liquid crystal polymer multilayer structure is derived from the heat-resistant fiber cushion material. The pattern to be transferred was not transferred, and the flow of the thermoplastic liquid crystal polymer and the collapse of the conductor pattern were not confirmed. Further, the heat-resistant cushioning material could retain its shape in the thermocompression bonding process, and no fusion to the platen occurred. Moreover, after releasing the pressure, the cushioning property was recovered again.

  On the other hand, since Comparative Examples 1-3, 8 and 13 used a polyester nonwoven fabric with low heat resistance as a cushioning material, the resulting thermoplastic liquid crystal polymer multilayer structure had no transfer derived from the polyester nonwoven fabric, The polyester melts due to a thermocompression bonding temperature equal to or higher than the melting point of the polyester resin (melting point: less than 260 ° C.) used in the nonwoven fabric, and the flow of the liquid crystal polymer cannot be stopped sufficiently, which is not practical. Further, since the polyester resin melts, the thermoplastic liquid crystal polymer multilayer structure is severely misaligned and cannot be stacked in many layers.

  In Comparative Examples 4 to 7, since the heat resistant cushion material was used without being combined with the metal plate, the flow of the thermoplastic liquid crystal polymer and the crushing of the conductor pattern were not confirmed, but the pattern derived from the heat resistant fiber cushion material was used. It has been transferred to the surface of the thermoplastic liquid crystal polymer multilayer structure.

  In Comparative Examples 9 to 13, since the size of the metal plate was larger than that of the pre-laminated body and the protective material was hot-pressed in a state where the protective material could not contact the side surface at the corners of the pre-laminated body, The pressure increased at the edge of the body, and even when any cushion material was used, the pressure became non-uniform and the resin flowed at the edge.

  According to the production method of the present invention, it is possible to efficiently produce a thermoplastic liquid crystal polymer multilayer structure, and the obtained thermoplastic liquid crystal polymer multilayer structure can be used in the electrical / electronic field, office equipment / precision equipment field, and the like. It can be effectively used as a component used in the above, for example, a circuit board (particularly, a millimeter wave radar board).

  As described above, the preferred embodiments of the present invention have been described. However, various additions, modifications, or deletions are possible without departing from the spirit of the present invention, and such modifications are also included in the scope of the present invention. It is.

100, 200, 300, 400, 500 ... Hot press machine 110 ... Upper platen 120 ... Lower platen 130, 230 ... Preliminary laminate 131, l32, 133, 231, 232, 233 ... Thermoplastic liquid crystal polymer substructure 142, 242 ... 1st protective material 144,244 ... 2nd protective material 150 ... 1st heat-resistant cushioning material 152 ... 1st metal plate 160 ... 2nd heat-resistant cushioning material 162 ... 2nd metal plate

Claims (8)

Selected from the group consisting of (i) a thermoplastic liquid crystal polymer film, (ii) a thermoplastic liquid crystal polymer film having a conductor layer on one side, and (iii) a thermoplastic liquid crystal polymer film having a conductor layer on both sides. A pre-laminated body in which at least two thermoplastic liquid crystal polymer substructures are superposed is heated and pressurized in a hot press machine through protective materials disposed on the upper and lower surfaces thereof to produce a thermoplastic liquid crystal polymer multilayer structure. A method,
On at least one of the upper and lower surfaces of the preliminary laminate, a heat-resistant cushion material and a metal plate are arranged in order from the hot press side,
Below the thermocompression bonding temperature of the thermoplastic liquid crystal polymer, the hot press is pressurized to the first pressure, and (I) the preliminary laminate is pressurized with the heat-resistant cushioning material and the metal plate through the protective material. (II) At the side of the preliminary laminate, the end of the protective material is sealed by pressurization of the heat-resistant cushion material, and (III) the protective material is in contact with all side surfaces of the preliminary laminate. A shape fixing step of fixing the shape so that the preliminary laminated body becomes the shape of a desired thermoplastic liquid crystal polymer multilayer structure by wrapping the preliminary laminated body in a state;
A thermocompression bonding step of depressurizing from the first pressure, raising the temperature to a thermocompression bonding temperature under a second pressure lower than the first pressure, and thermocompression bonding the adjacent thermoplastic liquid crystal polymer substructure;
A method for producing a thermoplastic liquid crystal polymer multilayer structure comprising: It is a manufacturing method of Claim 1, Comprising: The said conductor layer is selected from the group which consists of a conductor pattern, conductor foil, and a conductor film,
When a conductor pattern is formed on at least one of the upper surface and the lower surface of the thermoplastic liquid crystal polymer multilayer structure,
The protective material in contact with the surface on which the conductor pattern is formed is a multilayer composite material that can be deformed according to the shape of the conductor pattern,
The manufacturing method in which the protective material in contact with the surface on which the conductor pattern is not formed is a single layer sheet.   The manufacturing method according to claim 2, wherein the multilayer composite material is a first metal foil, a pair of high-density polyethylene sheets whose MD directions are orthogonal to each other, a second metal foil, and a low friction film. The manufacturing method currently formed.   It is a manufacturing method as described in any one of Claims 1-3, Comprising: The manufacturing method whose said heat resistant cushion material is a heat resistant fiber cushion material.   It is a manufacturing method of Claim 4, Comprising: The manufacturing method whose said heat resistant fiber cushion material is an organic fiber nonwoven fabric whose melting | fusing point or thermal decomposition temperature is 260 degreeC or more, or a metal fiber nonwoven fabric.   It is a manufacturing method as described in any one of Claims 1-4, Comprising: The manufacturing method whose difference of a 1st pressure and a 2nd pressure is 0.8-2.5 MPa. It is a manufacturing method as described in any one of Claims 1-6, Comprising: The length ( _CL ) of the vertical direction and the length ( _CW ) of the horizontal direction of the said heat resistant cushion material are preliminary | backup lamination | stacking. longitudinal length of the body (P _L) and the length of the lateral sides with respect to (P _W), with the following relationships, manufacturing method.
P _L + 1 ≦ C _L ≦ P _L +10 (unit: cm) and P _W + 1 ≦ C _W ≦ P _W +10 (unit: cm) A method according to any one of claims 1 to 7, the vertical length (M _L) and transverse side length of the metal plate (M _W) is, the heat-resistant cushion The longitudinal length (C _L ) and lateral side length (C _W ) of the material, and the longitudinal length (P _L ) and lateral side length (P _W ) of the preliminary laminate. In contrast, a manufacturing method having the following relationship:
P _L −1.0 ≦ M _L ≦ P _L (unit: cm)
P _W −1.0 ≦ M _W ≦ P _W (unit: cm)
C _L −11 ≦ M _L ≦ C _L −1.2 (unit: cm) and C _W −11 ≦ M _W ≦ C _W −1.2 (unit: cm)

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