JPS6328020B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an epoxy resin copper-clad laminate for industrial equipment, electronic parts, and electronic equipment, and its objectives are heat resistance, high adhesion to copper foil,
The object of the present invention is to obtain a copper-clad laminate with excellent adhesion between high-rise layers. Conventionally, epoxy resin copper-clad laminates for industrial equipment, electronic parts, and electrical equipment are used by adding amine curing agents such as dicyandiamide and diaminodichlorodiphenylmethane to the epoxy resin.
Adhesion with copper foil and interlayer adhesion are good, but the glass transition temperature is low at 130-160℃, and the epoxy resin softens due to the heat generated during drilling during multilayer printed circuit board manufacturing, causing the inner layer copper foil inside the drill hole to soften. It has the disadvantage that it adheres to the substrate and causes smear defects, and when connecting an LSI to a substrate by bonding, the substrate becomes soft due to heat and pressure, making it impossible to obtain a highly reliable connection. Furthermore, when an aromatic tetrabasic acid anhydride curing agent is added to an epoxy resin, the varnish has a short pot life. The present invention aims to improve the above-mentioned drawbacks, and uses glycerin tristrimeritate and 5-(2,5-dioxotetrahydrofuryl)-3 for epoxy resins having an epoxy equivalent of 250 to 800 as resins for laminates.
-By using a mixture of two types of curing agents, methyl-3-cyclohexene-1,2-dicarboxylic anhydride, the varnish has a long pot life, and has high heat resistance and high adhesion to copper foil. , it is possible to obtain an epoxy resin copper-clad laminate with excellent interlayer adhesion. Next, the present invention will be explained in detail. The base material for the laminate used in the present invention is woven fabric, nonwoven fabric, matte, paper, etc. made of inorganic fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol, and acrylic, and natural fibers such as cotton. General base materials for laminates, such as combination base materials.
The copper foil is not particularly limited, and copper foils used for trunk laminates are generally used. As resins for laminates, glycerin tristrimeritate (hereinafter simply referred to as TMMG) shown by the following structural formula and 5-(2,5- dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride (hereinafter simply referred to as
It is used by adding MCTC). In the present invention, it is extremely important to use an epoxy resin having an epoxy equivalent of 250 to 800 in order to obtain high adhesion to copper foil and interlayer adhesion. If the epoxy resin has an epoxy equivalent of less than 250, the adhesion to copper foil and interlayer adhesion will decrease, and if the epoxy equivalent exceeds 800, the melt viscosity of the resin will be extremely high, making it difficult to use the resin for laminates as a substrate for laminates. When preparing prepreg by impregnating and drying the material, the volatilization of the solvent is inhibited, causing a foaming phenomenon in the prepreg, which makes it difficult for air bubbles to escape from the laminate during lamination molding, resulting in void defects. Epoxy resins include glycidyl ether of bisphenol A, halogenated bisphenol A
Both glycidyl epoxy resins such as glycidyl ether and glycidyl amine type, and non-glycidyl epoxy resins such as alicyclic cyclohexene derivative type can be used. TMMG used in the present invention
Although it has excellent heat resistance and good adhesion to copper foil and interlayer adhesion, it has the disadvantage of poor storage stability as an epoxy resin varnish because of its rapid reactivity. In addition, MCTC used in the present invention has excellent heat resistance and relatively slow reactivity, so it has good storage stability as an epoxy resin varnish, but it has the disadvantage of poor adhesion to copper foil and interlayer adhesion. By using these two together, it has become possible to achieve performance that could not be achieved with TMMG and MCTC alone. i.e.
We found that an epoxy resin varnish using a combination of TMMG and MCTC has good storage stability, and a copper-clad laminate using this varnish has excellent heat resistance, high adhesion to copper foil, and high adhesion between layers. Also, for 1 epoxy equivalent of epoxy resin
It is essential that the blending amount of TMMG is in the range of 0.20 to 0.60 acid anhydride equivalent, and the blending ratio of MCTC is in the range of 0.15 to 0.70 acid anhydride equivalent. TMMG
If the blending amount is less than 0.20 acid anhydride equivalent, the adhesion with copper foil and interlayer adhesion will be poor, and
If the amount of TMMG exceeds 0.60 acid anhydride equivalent, the storage stability of the epoxy resin varnish will deteriorate. Furthermore, if the amount of MCTC blended is less than 0.15 acid anhydride equivalent, the storage stability of the varnish will be poor, while if it exceeds 0.70 acid anhydride equivalent, the adhesion of the copper foil and the interlayer adhesion will deteriorate. Of course, in order to adjust the curing speed, the epoxy resin varnish of the present invention may contain other curing agents, imidazoles, and a third
It is also possible to add curing accelerators such as grade amines. The epoxy resin composition of the present invention can also be used in paints and adhesives. As described above, the present invention provides a copper-clad laminate in which a base material for a laminate is impregnated with a resin for a laminate, and dried prepreg and copper foil are heated and laminated to form a copper foil. Since we used an epoxy resin with a hardness of 250 to 800, when making copper-clad laminates with epoxy resin, we can impregnate the epoxy resin and improve the adhesion between the dried prepreg and the copper foil, as well as the interlayer adhesion. It is possible to produce a copper-clad laminate with high adhesion to copper foil and high adhesion between high layers, and it also contains 0.20 to 0.60 acid anhydride equivalent of glycerin tristyrene per 1 epoxy equivalent of the above-mentioned epoxy resin. Melitate and 0.15 to 0.70 acid anhydride equivalents of 5-
(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride was used as the resin for the laminate to which two types of curing agents were added, so this epoxy resin It is possible to impart heat resistance, adhesion to copper foil, and interlayer adhesion, which are the characteristics of glycerin tristrimeritate, to varnishes, and also to provide 5-(2-5-dioxotetrahydrofuryl)-3-methyl-3 -It is possible to simultaneously impart the heat resistance and storage stability that are the characteristics of cyclohexene 1,2-dicarboxylic acid anhydride, and by using this epoxy resin varnish, heat resistance, high adhesion to copper foil, high-rise joint It can be made into a copper-clad laminate with excellent adhesion. Next, the present invention will be explained based on examples. Example 1 In a three-necked flask, 218 g of acetone, 46 g of ethyl cellosolve acetate, 13.7 g of TMMG (0.2 acid anhydride equivalent per 1 epoxy equivalent), MCTC 28.6
g (0.65 acid anhydride equivalent per 1 epoxy equivalent)
and heated at 60°C for 15 minutes to obtain a transparent solution. Then, to this solution was added 333 g of a solution type epoxy resin, which was prepared by dissolving 75 g of a halogenated bisphenol A type epoxy resin with an epoxy equivalent of 750 in 25 g of methyl ethyl ketone. Then, the mixture was further heated at 55 to 65°C for 15 minutes to obtain a transparent epoxy resin varnish. The above epoxy resin varnish is impregnated into a plain weave glass cloth with a thickness of 0.1 mm to a resin content of 45%, and dried to obtain a prepreg.Four sheets of this prepreg are laminated, and a layer of 0.035 mm thick is applied to the top and bottom surfaces of the epoxy resin varnish. The laminates each containing one sheet of surface-treated copper foil were sandwiched between molds and laminated at a molding pressure of 20 kg/cm ² at 190°C for 180 minutes to obtain a double-sided copper-clad epoxy resin laminate. . Example 2 The amount of TMMG was 41.0 g (0.60 acid anhydride equivalent for 1 epoxy equivalent), and the amount of MCTC was 11.0 g (1 epoxy equivalent).
A double-sided copper-clad epoxy resin laminate was obtained in the same manner as in Example 1, except that 0.25 acid anhydride equivalent (based on the epoxy equivalent) was used. Example 3 In a three-necked flask, 218 g of acetone, 46 g of ethyl cellosolve acetate, 77 g of TMMG (0.45 acid anhydride equivalent per 1 epoxy equivalent), MCTC 44.1
g (0.40 acid anhydride equivalent per 1 epoxy equivalent)
and heated at 60°C for 15 minutes to obtain a homogeneous solution. Next, to this solution was added solution type epoxy resin 294, which was prepared by dissolving 85 g of bisphenol A type epoxy resin with an epoxy equivalent of 300 in 25 g of methyl ethyl ketone.
g was added and further heated at 55 to 65°C for 15 minutes to obtain a transparent epoxy resin varnish. A double-sided epoxy resin laminate was obtained by carrying out the same treatment as in Example 1 except that the above epoxy resin varnish was used. Comparative Example 1 19.6 g of 4,4' diamino 3,3' dichlorodiphenylmethane and 0.70 g of 2-ethyl-4-methylimidazole
was dissolved in 160 g of methyl ethyl ketone, and then treated in the same manner as in Example 1, except that an epoxy resin varnish containing 307 g of the same solution type epoxy resin as in Example 1 was used to form a double-sided copper-clad epoxy resin laminate. Obtained. Comparative Example 2 The amount of TMMG was 6.8g (per 1 epoxy equivalent).
A double-sided copper-clad epoxy resin laminate was obtained by carrying out the same treatment as in Example 1, except that the amount of MCTC was (0.75 acid anhydride amount per 1 epoxy equivalent) (0.1 acid anhydride equivalent). Comparative Example 3 Same as Example 1 except that the amount of TMMG was 51.3 g (0.75 acid anhydride equivalent per 1 epoxy equivalent) and the amount of MCTC was 4.4 g (0.10 acid anhydride equivalent per 1 epoxy equivalent). A double-sided copper-clad epoxy resin laminate was obtained by the same treatment. Comparative Example 4 In a three-necked flask, 190 g of acetone, 40 g of ethyl cellosolve acetate, 92.2 g of TMMG (0.45 acid anhydride equivalent per 1 epoxy equivalent),
Add 52.8 g of MCTC (0.40 acid anhydride equivalent per 1 epoxy equivalent) and heat at 60°C for 15 minutes (obtain a homogeneous solution, then add 195 g of bisphenol A type epoxy resin with an epoxy equivalent of 195 to this solution. A double-sided copper-clad epoxy resin laminate was obtained by performing the same treatment as in Example 1, except that it was further heated at 55 to 65°C for 60 minutes and a transparent epoxy resin varnish was used.Examples 1 to 3 and Comparative Example 1 The following table shows the blending ratio and performance of the epoxy resin varnishes No. 4 to 4 and the performance of the obtained double-sided copper-clad epoxy resin laminate.

[Table] *2 Measured using a dynamic viscoelasticity measuring device.
*3 Width 4-10mm perpendicular to the vertical direction of the glass cloth
The interlayer adhesion between the first and second layers of four glass cloth layers cut into rectangles was measured using a shortcut tensile tester.
As shown in the table above, Comparative Example 1 uses a conventional curing agent, but the epoxy resin varnish has good storage stability, good adhesion to copper foil, and interlayer adhesion, but has a low glass transition temperature. It is. Furthermore, in Comparative Examples 2 and 3, TMMG was blended in an amount outside the range of 0.20 to 0.60 per epoxy equivalent of the epoxy resin, and in Comparative Example 2, where the blended amount of TMMG was less than 0.20, the interlayer adhesion was poor. , the amount of TMMG is
In Comparative Example 3 where the ratio exceeds 0.60, the storage stability of the epoxy resin varnish and the appearance of the prepreg made with this varnish were not good. Comparative Example 4 is an experimental result when the epoxy equivalent is outside the range of 250 to 800, particularly when the epoxy equivalent is less than 250, and the adhesion to copper foil and interlayer adhesion are poor. On the other hand, in Examples 1 to 3, good results were obtained in terms of storage stability, appearance, glass transition temperature, adhesion to copper foil, and interlayer properties.

Claims (1)

[Claims] 1. In a copper-clad laminate made by impregnating a laminate base material with a laminate resin and heating and laminating dry prepreg and copper foil, an epoxy resin with an epoxy equivalent of 250 to 800 is used as the laminate resin. 0.20 to 0.60 acid anhydride equivalents of glycerin tristrimeritate and 0.15 to 0.70 acid anhydride equivalents of 5 to 1 epoxy equivalent.
-(2,5-dioxotetrahydrofuryl)-3-
An epoxy resin copper-clad laminate characterized by using a material to which two types of curing agents, methyl-3-cyclohexene-1,2-dicarboxylic anhydride, are added.