JPS6236892A - laminate board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laminate for a printed wiring board.

(Prior Art) With the development of electronic devices, the demand for printed circuit boards is increasing year by year, and these days, electronic devices that do not use printed circuit boards have become so widespread that it can be said that there are no such devices.

The laminates (typically copper-clad laminates and screen printed circuit laminates) used in these electronic devices, etc.
Basic electrical properties, heat resistance, chemical resistance, water resistance, and other properties are required, and in addition, the high performance of electronic devices in recent years,
These requirements are becoming increasingly strict as devices become smaller, thinner, and lighter.

Currently, laminates for printed wiring boards include epoxy-glass laminates obtained by impregnating a cloth base material made of glass fiber with epoxy resin, laminating and curing it, and paper-based laminates made of dry oil-modified phenolic resin. Phenol-paper yarn is used, which is obtained by impregnating a material, laminating it, and curing it.

(Problems to be Solved by the Invention) A major problem with epoxy-glass laminates is that the density of glass fibers is high, and there is a limit to their use for the purpose of weight reduction. On the other hand, phenol-paper yarns have problems in electrical properties and water absorption. Recently, for the purpose of weight reduction, the use of a filter cloth base material made of fine aramid material has been considered, but it has high water absorption and therefore has problems with electrical characteristics, so it has not been used satisfactorily.

An object of the present invention is to overcome the above-mentioned problems and provide a laminate for a printed wiring board that is lightweight, non-water-absorbent, and has excellent electrical characteristics.

(Comprehensive means for solving the problem) The present invention involves impregnating a thermosetting resin into a filter cloth base material obtained by melt-spinning an aromatic polyester that exhibits anisotropy when melted, and laminating the filter cloth base material with a thermosetting resin. The present invention relates to a laminate for printed wiring boards obtained by molding and curing.

In the present invention, polyester that exhibits anisotropy when melted means that when a polyester sample powder is placed on a heated sample stage between two polarizing plates crossed at 90° and heated, in a temperature range where it can flow. It means something that has the property of transmitting light.

As such aromatic polyester,
It consists of aromatic dicarboxylic acids, aromatic diols and/or aromatic hydroxycarboxylic acids shown in Nos. 18016 and 55-20008, and derivatives thereof, and in some cases, these and alicyclic dicarboxylic acids. , alicyclic diols, aliphatic diols, and copolymers with these derivatives.

Here, the aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, 4,4'-dicarboxydiphenyl, 2,
Examples include 6-dicarboxynaphthalene, 1,2-bis(4-carboxyphenoxy)ethane, etc., and their alkyl, arylalkoxy, and halogen group-substituted products.

Aromatic diols include hydroquinone, resorcinol, 4
, 4'-dihydroxydiphenyl, 4.4'-dihydroxybenzophenone, 4°4'-dihydroxyldiphenylmethane, 4,4'-dihydroxydiphenylethane, 2.2-bis(4-hydroxyphenyl)propane, 4.4' -dihydroxydiphenyl ether, 4.4
Examples include '-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfide, 2,6-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, and their alkyl, aryl, alkoxy, and halogen-substituted products.

Aromatic hydroxybenzoic acids include p-hydroxybenzoic acid, m-hydroxybenzoic acid, 2-hydroxynaphthalene-6-carboxylic acid, and 1-hydroxynaphthalene-6-carboxylic acid.
Examples thereof include 5-carboxylic acid, etc., and nuclear substituted products of these alkyl, aryl, alkoxy, and halogen groups.

The alicyclic dicarboxylic acid is trans-1.

Examples include 4-dicarboxycyclohexane, cls-1°4-dicarboxycyclohexane, and substituted products of these with alkyl, aryl, and halogen groups.

As alicyclic and aliphatic diols, trsns-1,4
-dihydroxycyclohexane, cls-1,4-dihydroxycyclohexane, ethylene glycol, 1.4
-butanediol, xylylene diol, etc.

Among these combinations, preferred aromatic polyesters for the present invention include (1) copolyesters consisting of 40 to 7,030 moles of p-hydroxybenzoic acid residues and 15 to 30 moles of aromatic diol residues; (2) A copolyester consisting of terephthalic acid and/or isophthalic acid and chlorohydroquinone, phenylhydroquinone, and/or hydroquinone, (3) Consisting of 20 to 80 moles of p-hydroxybenzoic acid residues and 20 to 80 bonic acid residues. Examples include copolyester.

These starting materials can be used as they are or by esterification with aliphatic or aromatic monocarboxylic acids or derivatives thereof, aliphatic alcohols or phenols or derivatives thereof, etc. , carry out a polycondensation reaction.

As the polycondensation reaction, known bulk polymerization, solution polymerization, suspension polymerization, etc. can be adopted.
, a polymerization catalyst such as a Gθ compound, a stabilizer such as a phosphorus-based compound, a filler such as TiO, caco, 2, 3, or the like can be optionally added.

The obtained polymer is used as it is or as a powder by heat treatment in an inert gas or under reduced pressure to prepare a sample for spinning.

Alternatively, it can also be used after being granulated once using an extruder.

A known screw type extruder can be used as an apparatus for melt spinning in the present invention. The cylinder temperature of the extruder is 280 to 420 at the tip (maximum temperature).
℃, especially 300 to 400℃ is preferred.

The spun fibers are rolled up as they are, or coated with an oil and then rolled up. Winding or drawing speed is 10-1
The speed is preferably 0,000 m/min, but from the viewpoint of productivity and stable spinning, the speed is preferably 100 to 2,000 m/min. From the viewpoint of strength and elastic modulus, it is preferable that the thickness and cross-sectional shape of the obtained fine thread be 1 to 10 deniers. The obtained fibers can be used as they are, but they can be further increased in strength and elasticity by being subjected to heat treatment, stretching, or a combination of these treatments.

The strength of the fiber used in the present invention is lfl/d or more, preferably 20 y/c1 or more, and the elastic modulus is 500 y/d.
Above, preferably 700.9/d or more is SM.

In the present invention, the filter cloth base material refers to a cloth-like processed product formed by weaving, knitting, or making into a nonwoven fabric the above-mentioned delicate fabric.

It also includes thick two-dimensional cloth-like products and three-dimensional structures.

Usual weaving methods such as plain weave and satin weave can be used, and knitting methods such as stockinette knitting and plain knitting can be used.

Immediately after spinning, it can be blown with wind and cut into a non-woven fabric using a wire mesh, or it can be used as short fibers in the form of paper.

Preferred thermosetting resins to be impregnated into the obtained cloth base material include epoxy resins, phenol resins, unsaturated polyester resins, polyide resins, and polyamideimide resins. Epoxy resins are particularly preferred from the viewpoint of having no water absorption and electrical properties. These modified resins can also be used. For example, butadiene-modified resol resins and nitrile-modified epoxy resins are also effective.

These thermosetting resins can be impregnated into the fabric base material as monomers or oligomers as they are, or in the form of a solution or slurry. Alternatively, it is also possible to form a film or sheet and impregnate it by sandwich-molding the fabric substrate.

The fabric base material impregnated with thermosetting resin is then thermocompression molded to produce a laminate.

After this, if further circuitry is necessary, heat it up or write a circuit on it by screen printing.

In addition, it is more preferable to surface-treat the fibers and cloth base materials before impregnating them with the thermosetting resin in order to improve the adhesiveness with the thermosetting resin without impairing the electrical properties.

(Operations and Effects of the Invention) Fibers obtained by melt-spinning aromatic polyester that exhibits anisotropy when melted have high strength and high elastic modulus, and a printed wiring board formed from such fibers and using a filter cloth base material. The laminate is lightweight, has high strength, is non-water absorbent, and has excellent electrical properties.

The laminate of the present invention can be widely used in electronic devices that are becoming lighter, thinner, and shorter.

(Example) Reference examples, examples, and comparative examples are shown below in order to explain the present invention in detail, but these are merely illustrative and are not limited thereto.

In addition, the delicate tensile test in the example was carried out using an Instron universal testing machine Nn, 1130, with a test interval of 20 cm and a tensile speed of 0.5 corners y'ml n.

The optical anisotropy was measured by placing the sample on a heating stage, raising the temperature at 25° C./min under polarized light, and observing it with the naked eye.

The "dry" sample state for measuring electrical properties is 20℃, 651RH
``Wet'' means ``dry'' measurement, then immersed in water at 50°C for 48 hours, taken out,
Measurements were made by wiping the surface of the laminate with gauze. Water absorption rate is "dry"
"It was determined from the weight change of the wet J sample.

Volume resistivity and surface resistance are JIS K6911-5-
13, Takeda Riken ultra-high insulation needle Model T
It was determined using R-450 and applying a voltage of 500v.

Dielectric breakdown voltage is JIS K6911-5-11
-3.

The dielectric properties were determined by the mutual induction bridge method according to JIS K6911-5-14.

Reference example 1 p-acetoxybenzoic acid 7.2011 (40 mol), terephthalic acid 2.49 Kf (15 mol), isophthalic acid 0
．． 839 (5 mol) and 5.459 (20.2 mol) of 4,4'-diacetoxydiphenyl were charged into a polymerization tank with comb-shaped stirring blades, and the temperature was raised while stirring under a nitrogen gas atmosphere to 330°C. Polymerization was carried out for 3 hours. During this time, the acetic acid produced was removed and polymerization was carried out with strong stirring, after which it was gradually cooled and the polymer was taken out of the system at 200°C.

The yield of the polymer was 11.00 f, which was 98.2 h of the theoretical yield. This was crushed with a hammer made by Wire Micron Co., Ltd. into particles of 2.5 m or less.

When this was treated in a rotary kiln at 280° C. for 5 hours under a nitrogen atmosphere, optical anisotropy was observed at 350° C. or higher.

This polyester was melt-spun using a screw extruder with a diameter of 30 m. The nozzle used had a hole diameter of 0.07m.
, the hole length is 0.14 m and the number of holes is 308.

When spinning was carried out at a cylinder tip temperature of 380° C. and a spinning head temperature of 360° C., spinning was carried out extremely stably, and pale yellow transparent fibers were obtained. When the kernel fiber was treated in nitrogen at 320°C for 3 hours, it had a denier of 3.21, a strength of 29.11i/d1, an elongation of 2.9%, and a Yayoi ratio of 1,010.
, F/d.

Example 1 Using the delicate material of Reference Example 1, a plain-woven fabric was produced using an automatic loom manufactured by Tsudakoma Kogyo Co., Ltd. Thread density for both warp and weft is 1
It was set as 1 piece/am. This fabric was cut into 10CIIXIOQI pieces, and the epoxy resin [Epoxy ES] manufactured by Sumitomo Chemical Industries was used.
It was immersed in a methyl cellosolve solution of A-011 and an initiator (engineered poxy resin 100.F, 4 g of an initiator, and 40 g of methyl cellosolve), taken out, and air-dried.
It was left at 30° C. for 10 minutes to semi-cure. Layer ξ prepregs and heat at 160℃ for 30 minutes at 50Kf/cm2
Laminate compression molding at a pressure of 160°C for 1 hour after molding
After curing, a large number of molded products with a thickness of 2 to 3 m and a fiber volume fraction of 50% were produced.

Table 1 shows the density, water absorption, and electrical properties of this laminate. For comparison, aramid fiber Kevlar manufactured by Kanebo Co., Ltd.
■49 plain woven fabric K-281 (using 1,140 denier thread, thread density is 6.8 threads/C11 for both warp and width)
) and Nichisha Boseki's Ka5smWAla product WEA-18.
Table 1 shows the physical properties of a laminate made using -105-BZ-2 under the same conditions and method as above.

Table 1 shows that the laminate made from the polyester fiber fabric base material according to the present invention is lighter, has lower water absorption, and has better electrical properties than those made from aramid fiber and glass fiber. I understand.

Reference Example 2 Liquid polybutadiene 10 with physical properties of number average molecule [1230, cis 1,4 structure of 70 or more, vinyl structure of 3 or less]
01 p-nonylphenol 3011 phenol 120
y1) Luene 501 and BF, phenol saki salt 0.5I
liquid polybutadiene 1 was added to the mixture and reacted at 80°C.
A composition fAl was obtained in which an average of 5.5 molecules of phenol groups and p-nonylphenol groups were added per molecule.

The resulting composition (Al 10011, paraformaldehyde 16.OF, hexamethylenetetra-OF 3.0.F1, toluene 64y1 isopropyl alcohol 16/F1 as a solvent was added, and the mixture was reacted at 80°C for 2 hours. After compression, use toluene to reduce the resin content to 50 weight ff1
% of uniformly transparent LB modified resol varnish was produced.

Example 2 The cloth base material of the polyester fiber according to the present invention used in Example 1 was impregnated with the varnish of Reference Example 2, and after drying, it was laminated.
Pressure was applied at 60° C. and 100 Kf/cs2G for 40 minutes.

The fines volume fraction in the resulting laminate was 45 inches. Table 2 shows the physical properties of this laminate.

Reference Example 3 A polyester of 2°5-diacetoxydiphenyl and terephthalic acid was synthesized using the apparatus of Reference Example 1 and in the same manner. The same applies to post-processing. This polyester is 335
Optical anisotropy was observed above ℃. Using this polyester, melt spinning was carried out at a cylinder temperature of 365°C and a spinning head temperature of 350°C to obtain a yellow, transparent and delicate product. This delicate 3
When treated in nitrogen at 20°C for 3 hours, the result was 4.26 denier, strength 24.9 y/d, elongation 3.2 strokes, and elastic modulus 7.
It became 86 Ii/d.

Example 3 A plain weave fabric was made from the fine polyester of Reference Example 3 in the same manner as in Example 1, and an epoxy resin-impregnated laminate was made in the same manner as in Example 1.

Table 3 shows the physical properties of the laminate. Note that the fiber volume fraction in the laminate was 52%.

Claims (1)

[Claims] A laminate for printed wiring boards obtained by impregnating a fabric base material made from fibers obtained by melt-spinning aromatic polyester that exhibits anisotropy when melted with a thermosetting resin, laminating and curing the material.