JPH09208922A - Glass cloth and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a glass cloth, undergoing the fraying preventing treatment, favorable for the environmental sanitation and useful for carrying out the production of prepregs of good quality. SOLUTION: This glass cloth is obtained by coating the selvedge parts thereof with a polyamide resin, especially a water-soluble or a water-dispersible polyamide resin as a fraying preventing agent in a prescribed width and drying the coated polyamide resin. This method for producing the glass cloth is to coat both the selvedge parts of the glass cloth or the inside thereof with the polyamide resin as the fraying preventing agent, dry the coated polyamide resin and then cut the glass cloth leaving the fraying preventing agent in the prescribed width in both the selvedge parts. Since the fraying preventing agent used for the glass cloth is soluble in water, the agent does not cause pollution of working environment over the whole process ranging from the preparation thereof to drying and is effective in environmental protection. Furthermore, the fraying preventing agent is excellent in preventing effects on fraying when preventing cut part ends of the glass cloth from fraying without any difference in thickness between coated parts and other parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fray-preventing glass cloth for use in printed wiring boards and a method for manufacturing the glass cloth. More particularly, the present invention relates to a novel fixing agent for preventing fraying of a cut end of a glass cloth woven by a fragment loom such as an air jet loom (anti-fray). Further, the anti-fraying agent for glass cloth of the present invention is characterized by being a polyamide resin, particularly a water-soluble or water-dispersion type polyamide resin.

[0002]

2. Description of the Related Art In recent years, for weaving glass cloth, a fragment loom such as an air jet loom has become mainstream instead of a cored loom such as a fly shuttle loom. In the glass cloth woven by the fragment loom, the wefts are individually driven with a constant length and cut into a little longer than the width of the cloth,
It has the characteristic that "the ears" remain in both ears. When the glass cloth having such tufts is used as it is in the step of impregnating the varnish such as epoxy resin, the tufts excessively impregnate the varnish and the cut glass fibers adhere to the prepreg surface, resulting in cost reduction. However, it causes a problem in quality.

On the other hand, in the case of removing such tufts or in the case of dividing into two pieces or three pieces in order to obtain an arbitrary width not only in the fragment weaving machine but also in the glass cloth woven by the corrugated weaving machine, the anti-raveling treatment is performed. If you use it for the varnish impregnation process by simply mechanically cutting it without applying the glass varnish, the warp of the glass cloth will be easily frayed and it will wind around the roll, which will cause a great loss such as the need to stop the production line or take measures. Occurs. Therefore, in order to prevent the above-mentioned fraying,
The following methods have been studied.

That is, an attempt was made to cut the glass yarn while melting and adhering the glass yarn with the laser beam at the tufted portion or the ground portion of the glass cloth. However, its adhesive strength is weak, and there are drawbacks such as easy peeling of the adhesive part even with a slight squeezing, and minute molten balls at the end of the glass yarn that are formed during melting and dropping into the varnish. Has not reached.

Attempts have also been made to use thermosetting resins such as epoxy-based or phenol-based resins (JP-A-4-19110, JP-A-6-2277).
JP-A-5-222676, JP-A-6-19296
No. 5 publication). However, even though glass cloth has a relatively high resistance to solvents such as methyl ethyl ketone, methyl cellosolve, toluene, hexane, acetone, and dimethylformamide contained in varnishes such as epoxy resin, it does not harden until it is cured after being applied to the glass cloth. It takes a considerable amount of time, and there are problems in terms of equipment and productivity.

Attempts have been made to use thermoplastic resins such as polyethylene terephthalate, polybutylene terephthalate, polyphenylene ether, and ethylene-vinyl acetate copolymer. Among them, conventionally used ethylene-vinyl acetate copolymers and the like have insufficient solvent resistance and are not preferable for use in printed wiring board applications.

Attempts have also been made to use a solution of polyethylene terephthalate or the like in a halogenated lower hydrocarbon solvent such as methylene chloride or chloroform (Japanese Patent Laid-Open Nos. 59-15563 and 60). -194182, JP-A-63-31567
4, JP-A-63-85158, JP-A-2-
No. 216277, JP-A-5-321153,
JP-A-6-57665 and JP-A-6-200480.
No.). This method can almost solve the problems in prepreg production, but as is well known, solvents such as methylene chloride are unfavorable solvents in the working environment.
The biggest issue is environmental measures.

That is, it is necessary to make a closed system for all steps of solution preparation, storage, coating, and drying, which results in a large capital investment and an increase in the manufacturing cost of glass cloth.
There are still problems to be solved. Moreover, the use of such an organic solvent is not preferable in terms of environmental protection.

[0009]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the prior art as described above and, in addition, it is preferable in terms of environmental hygiene and prevents fraying which is useful for producing a high quality prepreg. The purpose is to provide the applied glass cloth.

[0010]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that a polyamide resin is effective as an anti-raveling agent for the cut end of a glass cloth. The invention was completed. That is,
The present invention provides a glass cloth in which a polyamide resin is applied to a certain width of the ear portion of the glass cloth. It is also characterized in that the polyamide resin is water-soluble. It is also characterized in that the polyamide resin is a water dispersion type resin. Both ears of the glass cloth or the inside thereof, a polyamide resin is applied as a fray-preventing agent, and after drying, the fray-preventing agent is cut into both ears to leave a constant width, and the glass cloth is produced. I will provide a. Less than,
The present invention will be described in detail.

[I] Anti-raveling agent: The present invention is a novel adhesive agent for preventing raveling (prevention of ear raveling) of a cut end of a glass cloth woven by various types of looms, particularly a fragment loom such as an air jet loom. As a characteristic, a polyamide resin, in particular, a water-soluble or water-dispersion type polyamide resin is used. Specifically, it relates to a glass cloth obtained by applying a polyamide resin as a fray-preventing agent of the present invention to a certain width of the ears of the glass cloth and drying it.

The polyamide resin used in the glass cloth of the present invention is not particularly limited, but in addition to polycondensation of carboxylic acid and amine, polycondensation of various acid derivatives with amine and ring-opening polymerization of lactam. , Ring-opening polymerization involving decarboxylation of N-carboxy-α-amino acid anhydride,
Hydrogen transfer polymerization of acrylamide, solid-phase peptide synthesis by Merrifield method, anionic polymerization of isocyanate,
A polyamide resin obtained by liter polymerization of dinitrile and diester, copolymerization of ethyleneimine and carbon monoxide, or the like can be used.

From the viewpoint of environmental hygiene, it is particularly preferable to use a water-soluble or water-dispersible polyamide resin with water as the solvent. A water-soluble or water-dispersible polyamide resin is generally obtained by water-solubilizing an insoluble polyamide resin, for example, a polyamide resin obtained by ring-opening polymerization of a lactam (eg, N-methoxymethylated nylon, N- Ethoxymethylated nylon,
A hydrophilic monomer (acrylic acid, methacrylic acid, hydroxyethyl acrylate, polyethylene glycol monomethacrylate, itaconic acid, acrylamide, N-methylol acrylamide, etc.) is added to N-alkoxymethylated nylon such as N-butoxymethylated nylon.
Graft-polymerized (1: 0.3 weight ratio) (Japanese Patent Publication No. 7-25854) and

Lactams (eg, ε-caprolactam and mixtures thereof with small amounts of other lactams: other lactams include 2-pyrrolidone, δ-valerolactam, enanlactam, η-laurolactam, etc.) and polyols (eg, , A molecular weight of 100 to mainly oxyethylene units
3,000 polyols: Examples of polyols include polypropylene glycol, polypoxyethylene / oxypropylene glycol copolymer, polytetramethylene glycol, polycaprolactone diol, polybutadiene diol and hydrogenated products thereof in the presence of a catalyst. Anionically polymerized in JP-A-61-20312
No. 8),

Polyalkylene glycol (eg,
Polyethylene glycol, polypropylene glycol, etc.) copolyamide, ε-capronamide having a tertiary amino group, N- having a tertiary amino group in the main chain
A polyamide having a water-soluble hydrophilic property such as a copolyamide having a urea unit obtained by condensing an alkyliminobispropylamine and ε-caprolactam or a polycopolymerized polyamide (Japanese Patent Laid-Open No. 59-78239). ,

A diamine having a tertiary amino group and / or an oxyethylene group in the main chain [eg, N, N′-bis (γ-aminopropyl) piperazine, N- (β-aminoethyl) piperazine, etc. A monomer containing a tertiary amino group, an alkyldiamine containing an oxyethylene group in the main chain such as oxyethylene alkylamine] and a dicarboxylic acid (for example, adipic acid, sebacic acid, etc.) and further co-condensed Polymerization component (for example, α-pyrrolidone,
and α-piperidone, ε-caprolactam, etc.) are also copolymerized (Japanese Patent Publication No. 5-4348).

The water-soluble polyamide resin thus obtained generally exhibits rubber elasticity and is flexible, and its heat resistance and solvent resistance are remarkably improved as the crosslinking reaction proceeds.
Such a polyamide resin is applied to a portion of the glass cloth to be cut with a constant width. Upon coating, the polyamide resin should be 300 cps or less, preferably 100 cps
It is preferably diluted with a solvent to a viscosity of ps or less, more preferably 5 to 30 cps. The viscosity of polyamide resin is 3
A liquid thicker than 00 cps is not preferable because it does not sufficiently impregnate the single yarn of the glass cloth.

Solvents for reducing the viscosity of the polyamide resin include methylene chloride, carbon tetrachloride, chloroform,
Halogenated lower hydrocarbon solvents such as trichloroethylene and alcohols, ethers, ketones and the like are used, but water is most preferable from the viewpoint of preventing human body or environmental pollution. On the other hand, the resin may be used in combination with other resins such as melamine resin, epoxy resin, urethane resin, or mixed with a curing agent such as citric acid or lactic acid or a curing accelerator thereof.

[II] Manufacturing Method of Anti-Fray Glass Cloth As a method for applying the anti-fray agent to the glass cloth, a die coater, a spray coater, a roll coater and the like can be mentioned. The coating width should be as narrow as the adhesive strength allows, but in industrial production, considering the variation, it is 10
mm or less, preferably 4 to 8 mm. It is important to adjust the coating amount so that the resin solid content is 2 to 10% by weight, preferably 2 to 6% by weight, based on the coated portion of the glass cloth. At this time, if it is less than 2% by weight, a sufficient anti-raveling effect cannot be obtained, and if it exceeds 10% by weight, the applied portion becomes thicker than the other portions, causing abnormalities such as ear height.

According to the method of the present invention, a polyamide resin is applied as a fray-preventing agent to both ears of the glass cloth or the inside thereof, and after drying, the fray-preventing agent is left in both ears at a certain width to leave a certain width. The present invention relates to a method for manufacturing a glass cloth, which comprises cutting the glass cloth. In the method of the present invention, the glass cloth coated with the anti-raveling agent is further dried in a dryer under the condition that the moisture contained in the anti-raveling agent scatters without being overheated within a predetermined time. Although not particularly limited, for example, 100 to 200 ° C. and 5 to 30 seconds are suitable.

Any of the heating methods may be used to dry the anti-fray agent applied to the glass cloth, and examples thereof include a hot air drying method, an infrared drying method, a microwave drying method, and a cylinder drying method. The infrared drying method and the microwave drying method are preferable because it is desirable to avoid heating of a portion other than the anti-raveling agent application portion. After drying,
It does not matter if a melting step at 200 to 300 ° C. is added.
After passing through the drying and melting steps, the glass cloth is cut with a slitter at approximately the center of the applied anti-fray agent.
As the cutting position, it is desirable to cut the center of the coating width, but in industrial manufacturing, it is desirable to take the variation into account and the coating width center line ± 20% of the coating width. Therefore, the glass cloth after cutting has a width of 7 mm or less in both ears, preferably 2 to
The anti-fraying agent having a width of 4 mm is applied, and the ears including the tufts are removed from the glass cloth.

In the glass cloth used in the present invention, the number of warp threads and weft threads per unit length, the thickness, and the weight per unit area correspond to the Japanese Industrial Standard R-3414 and the US military standard (MIL standard). However, the present invention is not limited to this, and any one can be used.
For example, this glass fiber may have not only E glass and C glass but also various glass components such as S glass, H glass, and D glass. Further, any of the glass cloth at the stage where the sizing agent necessary for weaving is attached, the glass cloth at the stage where the sizing agent is removed, or the glass cloth which has been already treated with a silane coupling agent or the like by a known surface treatment method. But good.

[0023]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, which do not limit the scope of the present invention. (Example 1) Water-soluble polyamide resin (fine resin N
K-1001 (produced by Lead City Co., Ltd.) was diluted with a mixed liquid of water and methyl alcohol (methyl alcohol: water = 7: 3) to prepare a 10% by weight anti-raveling agent. The anti-raveling agent was applied to the inside of both ears of the glass cloth along the warp with a width of 10 mm by a roll coater, and then dried at 120 ° C. for 30 seconds. At this time, the adhesion amount of the anti-raveling agent is
It was 3% by weight based on the coated portion of the glass cloth (7628, manufactured by Asahi Schwebel Co., Ltd.).

Further, in the glass cloth, the central portion of the applied anti-raveling agent was cut with a slitter. After cutting, the strength at the time of peeling off one warp yarn at the most end perpendicularly to the warp yarn was measured by a tensile tester (Autograph AGS-500D,
(Manufactured by Shimadzu Corp.) and measured as dry ear strength. In addition, a glass cloth that had been soaked in dimethylformamide for 5 minutes and then air-dried was measured in the same manner to obtain a wet ear strength. On the other hand, the thickness of the central portion of the glass cloth and the thickness of the anti-fraying agent applied portion were measured, and the thickness ratio was calculated according to the following equation. Thickness ratio = thickness of anti-fraying agent applied portion + thickness of central portion of glass cloth

Example 2 Example 1 was repeated except that a water-soluble polyamide resin (Toresin FS-350, manufactured by Teikoku Kagaku Sangyo Co., Ltd.) was diluted with water to prepare a 10% by weight anti-raveling agent. I went the same way. (Example 3) Water-soluble polyamide resin (AQ nylon A-
90, manufactured by Toray Industries, Inc., was diluted with water, and the same procedure as in Example 1 was performed except that 10% by weight of the anti-raveling agent was prepared.

(Comparative Example 1) The same as Example 1 except that a polyester resin (HARDIC A-1300, manufactured by Asahi Kasei Kogyo Co., Ltd.) was dissolved in trichlorethylene to prepare 10% by weight of an anti-raveling agent. Went to. The results are shown in Table 1 below.

[0027]

[Table 1]

[0028]

EFFECTS OF THE INVENTION The glass cloth, which has been prevented from fraying according to the present invention, uses polyamide resin as a fraying-preventing agent, and therefore has a large adhesive strength and an excellent ear fraying property. Further, since the coating has flexibility, the glass cloth of the present invention may be wound, disentangled, or cracked or broken at the coated portion even when passing through a roll in the process, or wavy ears. There is no occurrence. Since the polyamide resin used as the anti-raveling agent in the present invention has good resistance to the solvent used for the varnish, the ears do not fray during the steps of impregnating and drying the varnish.

Furthermore, since the polyamide resin anti-fray agent used in the present invention is water-soluble, there is no work environment pollution during the entire process from adjustment to coating and drying, and it is also effective for environmental protection. The glass cloth obtained by the method of the present invention has almost no difference in thickness between the ear portion and the other portion,
When a prepreg is manufactured using the glass cloth, cut into a certain size and stacked, a difference in height between the central portion and the end portion hardly occurs. As described above, the glass cloth according to the present invention can be effectively used for printed wiring board applications.

Claims (4)

[Claims] 1. A glass cloth in which a polyamide resin is applied as a anti-raveling agent to a certain width of an ear portion of the glass cloth. 2. The glass cloth according to claim 1, wherein the polyamide resin is water-soluble. 3. The glass cloth according to claim 1, wherein the polyamide resin is a water dispersion type resin. 4. Both ears of the glass cloth or inside thereof,
A method for producing a glass cloth, which comprises applying a polyamide resin as an anti-raveling agent and drying it, and then cutting the glass cloth with leaving a certain width of the anti-raveling agent on both ears.