JPH0919976A - Composite laminated plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composite laminated plate free from the obscurity, discoloration by heating, heat deterioration, and solvent resistance of a resist image by the simultaneous exposure of both surfaces. SOLUTION: In a central layer, a nonwoven fabric is used as a substrate, and an epoxy resin is used as a matrix resin which contains 0.01-0.1wt.% of an organic ultraviolet absorbing agent which absorbs ultraviolet rays 300-450nm in wavelength, 0.1-2wt.% of titanium oxide, and 60-120wt.% of one or more kinds of inorganic fillers selected from clay, talc, aluminum hydroxide, wollastonite, silica, alumina, calcium aluminate, and calcium carbonate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite laminate excellent in ultraviolet ray shielding property. The laminated board of the present invention is particularly suitable for electrical insulation or a printed wiring board, but is not limited thereto.

[0002]

2. Description of the Related Art In the process of manufacturing a printed wiring board, there is a step of forming a solder resist. This solder resist plays an important role in preventing short circuits due to solder bridges between lines during soldering and for permanent protection of conductor patterns. In recent years, a photo printing method has been adopted as a method for forming a solder resist, and simultaneous double-sided exposure has come to be carried out. Therefore, even in the case of glass-based epoxy resin laminates for high-density wiring boards, and glass cloth and glass nonwoven fabric composite substrate epoxy resin laminates with excellent processability, so-called composite laminates, both sides can be exposed simultaneously, It has become necessary to prevent the transmission of light.

Known examples of the ultraviolet ray impermeable laminated plate include a laminated plate in which a matrix resin is mixed with an ultraviolet absorber, and a laminated plate in which an ultraviolet ray shielding agent is adhered to a glass fiber base material. As the organic UV-screening agent to be added to the matrix resin, organic UV-absorbing agents such as benzophenone and benzotriazole are known, organic fluorescent whitening agents such as coumarin, and inorganic UV-screening agents such as titanium oxide. . Furthermore, a large amount of inorganic filler such as clay or calcium carbonate is added to block ultraviolet rays.

[0004]

However, the laminated plate containing the ultraviolet absorber has a problem of discoloration due to heating, thermal deterioration,
There are drawbacks such as a decrease in solvent resistance and deterioration of the absorbent itself due to light, resulting in uneven properties. Further, the laminated plate containing titanium oxide satisfies the required performance in terms of heat resistance, but the proportion of long-wavelength ultraviolet rays that do not absorb and diffusely reflect increases, and the use of high-sensitivity resist blurs the resist image. . Further, a large amount of an inorganic filler such as clay or calcium carbonate must be used, the viscosity of the resin becomes high, and it becomes difficult to impregnate the base material. It is an object of the present invention to obtain a composite laminate having excellent UV shielding properties without impairing the original properties of the laminate.

[0005]

[Means for Solving the Problems] The inventors of the present invention have studied various ultraviolet shielding materials and have reached the present invention. In the present invention, the central layer is made of a non-woven fabric as a base material, and 0.01 to 0.1% by weight of an organic ultraviolet absorber that absorbs ultraviolet rays having a wavelength of 300 nm to 450 nm, titanium oxide of 0.1% to 2% by weight, and , Clay, talc, aluminum hydroxide, wollastonite, silica, glass powder, magnesium hydroxide, alumina, calcium aluminate or calcium carbonate 1
A composite laminate comprising an epoxy resin containing 60 to 120% by weight of one or more inorganic fillers as a matrix resin.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of organic ultraviolet absorbers include hydroxybenzophenones, hydroxybenzotriazoles, diaminostyrylbenzyl sulfonic acid derivatives, imidazole derivatives and coumarin derivatives. Examples thereof include 2-hydroxy-4-octoxybenzophenone, 2- (2-hydroxy-5-methyl-phenyl) benzotriazole, 4-methyl-7-diethylaminocoumarin, bis- (1,5-diphenyl). −
Pyrazolin-3-yl) -styrene, 1- (phenyl)
-3--3- (4-tert-butyl-styryl) -5-
(4-tert-butyl-phenyl) -pyrazoline and the like can be mentioned. Two or more of these may be used in combination without any problem.

Of these, particularly suitable are 4-methyl-7-diethylaminocoumarin, bis- (1,5-diphenyl-pyrazolin-3-yl) -styrene, 1-
(Phenyl) -3-3- (4-tert-butyl-styryl) -5- (4-tert-butyl-phenyl) -pyrazoline.

Further, in the present invention, in addition to the organic ultraviolet absorber, titanium oxide powder and an inorganic filler are used in combination. Examples of the inorganic filler used in combination include clay, talc, aluminum hydroxide, wollastonite, silica, glass powder, magnesium hydroxide alumina, calcium aluminate, calcium carbonate, etc. These are used alone or in combination as necessary. can do. The maximum particle size of titanium oxide and the inorganic filler is 10 to 100 μm.
m, preferably 40 μm or less.

As the base material of the central layer, a glass non-woven fabric in which short fibers such as E glass, C glass, D glass and S glass are bonded with an organic binder is used. A non-woven fabric obtained by mixing glass fibers with cellulosic fibers or organic fibers may be used. 0.01% by weight to 0.1% by weight of an organic ultraviolet absorber is added to a commonly used epoxy resin varnish, and then 0.1% by weight to 2% by weight of titanium oxide and 60% by weight to 120% by weight of an inorganic filler. %, And the glass nonwoven fabric base material is impregnated with the varnish uniformly dispersed. A woven fabric made of fibers such as E glass, C glass, D glass, and S glass is used as the base material of the surface layer, and the matrix resin of the surface layer may be any epoxy resin for the laminated plate, and is not particularly limited. .

If the amount of the organic ultraviolet absorber added is less than 0.01% by weight, the effect is small, and if it is more than 0.1% by weight, the solvent resistance is lowered and discoloration due to heating occurs. Further, titanium oxide is preferably 2% by weight or less. This is because there is little change in hue when the laminate is used. Furthermore, if the amount of the inorganic filler used in combination with titanium oxide is 60% by weight or less, the effect of increasing the amount is small, and if it is 120% by weight or more, the viscosity of the resin increases, making it difficult to impregnate a glass fiber base Will be.

An electrical laminate comprising a glass fiber base material and an epoxy resin composition is prepared by impregnating a glass fiber base material with the epoxy resin composition, stacking several prepregs obtained by curing the resin to the B stage, and applying heat and pressure. Obtained. When the central layer is composed of a plurality of prepregs, at least one of the prepregs may have an ultraviolet shielding property, and it is not necessary that all the prepregs composing the central layer have an ultraviolet shielding property.

[0012]

Function: Wavelength of 300 nm to 450 for organic resin
The organic UV absorber that absorbs UV of 0.01 nm is 0.01 to
An epoxy resin composition containing 0.1% by weight, titanium oxide of 0.1% by weight to 2% by weight, and an inorganic filler of 60% by weight to 120% by weight, and a glass non-woven fabric substrate are used as a central layer. Therefore, the UV absorber does not come into direct contact with the outside air,
It is resistant to discoloration and thermal deterioration due to heating and has good solvent resistance. In addition, the combined use of organic UV absorber and titanium oxide can reduce the amount of each used, discoloration due to heating due to the organic UV absorber, the effect of thermal deterioration, and diffuse reflection of long wavelength ultraviolet rays due to titanium oxide. Is less.
As a result, blurring of the resist image is eliminated, and the hue change of the laminated plate is reduced. The surface layer uses a conventionally used epoxy resin, and the center layer uses a small amount of organic UV absorber and titanium oxide in addition to the inorganic filler conventionally used in composite laminates. It is possible to obtain a composite laminate having the same electrical properties, chemical properties, mechanical properties, and economy as those of the above composite laminate and having a good ultraviolet shielding property.

[0013]

【Example】

Preparation of Resin Varnish A Brominated epoxy resin (epoxy equivalent 470 g / eq,
Bromine content 21.0%) 100 parts (parts by weight, the same applies hereinafter), dicyandiamide 3 parts, 2-ethyl-4-methylimidazole 0.17 parts, ethylene glycol monomethyl ether 25 parts and N, N dimethylformamide 25.
The parts were mixed to obtain a resin varnish A.

Preparation of Resin Varnish B Resin varnish A was mixed with 70 parts of aluminum hydroxide and 2 parts of talc.
0 part, 1- (phenyl) -3-3 (4-tert-butyl-styryl) -5- (4-tert-butyl-phenyl) -pyrazoline 0.05 part by weight, titanium oxide 0.5 part by weight are mixed. A resin varnish B was obtained.

Preparation of Resin Varnish C Resin varnish A was mixed with 70 parts of aluminum hydroxide and 2 parts of talc.
Resin varnish C was obtained by mixing 0 parts.

A resin varnish A having a thickness of 0.2 mm and a basis weight of 2
A glass cloth of 10 g / m ² was impregnated with a resin content of 42% by weight and dried to obtain a prepreg for a surface layer. The resin varnish B was impregnated into a glass non-woven fabric having a thickness of 0.4 mm and a basis weight of 75 g / m ^{2 so} that the resin content was 90% by weight, and dried to obtain a prepreg for the center layer. One prepreg for the center layer is sandwiched by two prepregs for the surface, and a thickness of 18
A copper foil having a thickness of μm was arranged, and press-molded at 170 ° C. for 90 minutes under the condition of 3 MPa to obtain a double-sided composite copper-clad laminate having a thickness of 0.8 mm.

Comparative Example 1 A resin varnish A having a thickness of 0.2 mm and a basis weight of 210 g / m ^{2 was used.}
Impregnating the glass cloth of so that the resin content is 42% by weight,
A prepreg for a surface layer was obtained by drying. Resin varnish C
A glass non-woven fabric having a thickness of 0.4 mm and a basis weight of 75 g / m ² was impregnated with a resin content of 90% by weight and dried to obtain a center layer prepreg. One prepreg for the center layer is sandwiched between two prepregs for the surface layer, a copper foil having a thickness of 18 μm is arranged on the outer side, and press-molded under the conditions of 170 ° C., 90 minutes and 3 MPa, and a thickness of 0.8 mm. A double-sided composite copper clad laminate was obtained.

Comparative Example 2 A resin varnish A having a thickness of 0.2 mm and a basis weight of 210 g / m ^{2 was used.}
Impregnating the glass cloth of so that the resin content is 42% by weight,
A prepreg for a surface layer was obtained by drying. Similar to the prepreg for the surface layer, resin varnish A, thickness 0.4 mm, basis weight 75
A glass non-woven fabric of g / m ² was impregnated with a resin content of 90% by weight and dried to obtain a prepreg for a center layer. One prepreg for the center layer is sandwiched between two prepregs for the surface layer, and a copper foil having a thickness of 18 μm is arranged outside the prepreg for 170 ° C.
Press-molded under the condition of 0 minutes, 3 MPa, thickness 0.8 mm
A double-sided composite copper-clad laminate was obtained.

The electrical properties, chemical properties, and mechanical properties of the laminates obtained in the examples were equivalent to those of the laminates obtained in Comparative Examples 1 and 2.

Next, with respect to each of the obtained double-sided copper-clad laminates, the copper foil was removed by etching, and the copper foil was 700
Irradiation with ultraviolet rays of mJ / cm ² was carried out, and ultraviolet ray transmittances at wavelengths of 350 nm and 420 nm were obtained. The UV illuminance meter used was UV-MOI manufactured by Oak Manufacturing Co., Ltd., and the sensors used were UV-35 and UV-42. Table 1 shows the results.

[0021]

[Table 1]

Next, with respect to each of the obtained double-sided copper-clad laminates, copper foil was etched to form a simulated pattern, and a photosensitive solder resist film was laminated on both surfaces thereof. Then, both sides were simultaneously exposed through the respective masks on the front and back sides and developed, and the resolutions were compared by the edge shapes. As a result, the edge shapes of the laminates of Examples were sharp, but the edge shapes of the laminates of Comparative Examples 1 and 2 were unclear.

[0023]

As described above, according to the present invention, a composite laminate having a good ultraviolet shielding property can be obtained by using an organic ultraviolet absorber, titanium oxide and an inorganic filler in combination.

Claims (1)

[Claims] 1. The center layer is made of a non-woven fabric as a base material and has a wavelength of 30.
0.01 to 0.1% by weight of an organic ultraviolet absorber that absorbs ultraviolet rays of 0 nm to 450 nm, 0.1% by weight of titanium oxide
2% by weight and one or more inorganic fillers 6 selected from clay, talc, aluminum hydroxide, wollastonite, silica, glass powder, magnesium hydroxide, alumina, calcium aluminate or calcium carbonate 6
A composite laminate comprising an epoxy resin containing 0 to 120% by weight as a matrix resin.