JPH0137264B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a thermosetting resin laminate that imparts bacterial resistance. Laminated boards made of thermosetting resins such as epoxy resins, phenolic resins, silicone resins, polyimide resins, and polyurethane resins are susceptible to the growth of fungi (mold, bacteria, etc.) when exposed to high humidity. Thermosetting resin laminates include those used as electrical insulating materials, and printed wiring laminates with metal such as copper foil pasted thereon. When bacteria grow on such thermosetting resin laminates, the insulation deteriorates drastically.
Significant damage will occur, such as erosion of circuits and changes in appearance. Conventionally, in order to effectively prevent the growth of bacteria,
Paints containing antibacterial agents have been applied to processed products such as laminates and copper-clad laminates. However, it is more rare to impart bacteria resistance to the thermosetting resin laminate itself. However, as described below, in the case of thermosetting resin laminates, prepregs are manufactured by using a varnish-impregnated base material through a high-temperature drying process, so even if an antibacterial agent is added to the varnish,
In the drying process, the antibacterial agent evaporates and is lost, or the antibacterial agent is contained inside the laminate in addition to the surface of the laminate, which is not only not effective in imparting antibacterial properties, but also reduces electrical performance. There were drawbacks that could have a negative impact on the A commonly used method for manufacturing a thermosetting resin laminate will be explained step by step. Depending on the purpose of use, thermosetting resins such as epoxy resins, phenolic resins, silicone resins, polyimide resins, and silicone resins are dissolved in a solvent to make a varnish. A solvent is further added to the varnish to obtain a suitable viscosity for impregnation, and a substrate such as glass cloth or paper is impregnated with this. Then add this one to 150
Heat in an oven at ~180℃ for 5 to 20 minutes, dry,
Semi-cured prepreg. Layer several sheets of prepreg (for printed wiring boards, place copper foil on top) and heat at 150 to 180℃.
Sandwiched between press heating plates heated to 10 to 150
A laminate is obtained by heating and pressing at a pressure of Kg/cm ³ for 60 to 180 minutes. The present inventors have studied various methods for producing a laminate in which antibacterial agents act effectively, and have devised the production method of the present invention as shown below. That is, the present invention impregnates a base material with a thermosetting resin varnish and dries it to form a prepreg, sprays a p-chloro-m-xylenol solution onto the surface of the prepreg, and dries it at room temperature, that is, a low temperature of 50°C or less. , a laminated layer having bacterium resistance, characterized in that p-chloro-m-xylenol is attached in a proportion of 0.1 to 2.0% by weight based on the resin content in the prepreg, and then the prepregs are laminated and heated and pressurized. This is a method of manufacturing a board. The thermosetting resin varnish used in the present invention is
It can be applied to varnishes of thermosetting resins, such as epoxy resins, phenolic resins, polyimide resins, silicone resins, or modified resins thereof, which should undergo semi-cured prepreg in the process of manufacturing laminates. These resin varnishes are impregnated into base materials such as glass cloth, linter paper, and kraft paper under appropriate conditions and dried. The antibacterial agent used in the present invention includes p-chloro-m-xylenol (hereinafter referred to as
(abbreviated as PCM) is used. To attach PCM to the prepreg surface, it is dissolved in a solvent that dissolves and evaporates easily, and applied by spraying.
It is preferable to dry the solvent at room temperature or at a low temperature of 50° C. or lower, which corresponds to the boiling point of acetone or lower. P.C.M. One of the cases in which the present invention is most effective is when a laminate having bacterium resistance is created using the above method. PCM can be considered to be added in the varnish melting process of the general thermosetting resin laminate manufacturing method described above, but PCM easily volatizes.
It volatilizes during heating and drying, making it impossible to obtain a laminate with antibacterial properties. According to the present invention, even a volatile antibacterial agent can be effectively left on the surface of the prepreg. As a result of examining the amount of PCM deposited, good results were obtained when it was deposited at a ratio of 0.1 to 2.0% by weight based on the resin content in the prepreg. The amount of adhesion
If it is less than 0.1% by weight, sufficient bacterial resistance cannot be obtained.
Furthermore, if the amount exceeds 2.0% by weight, it will adversely affect soldering heat resistance, chemical resistance, peel strength, moldability, etc. In the present invention, the laminate and copper-clad laminate obtained using PCM have both antibacterial properties and electrical properties, and can also satisfy various properties as a printed wiring board. In the present invention, there is no need to particularly change the conditions for impregnating and drying the prepreg and the laminating heating and pressurizing conditions from those generally used for thermosetting resin laminates. According to the present invention, in the prepreg impregnation and drying process,
PCM does not volatilize and is effective only on the prepreg surface, which is effective in imparting bacterial resistance to laminates.
By attaching PCM, it is possible to produce a laminate with excellent bacteria resistance. Examples are shown below. Parts and % mean parts by weight and % by weight, respectively. Example 1 Manufacture of varnish: 80 parts of Epicote 1001 (epoxy resin manufactured by Ciel Chemical Co., Ltd.) and 20 parts of Epicote 828 (epoxy resin manufactured by Ciel Chemical Co., Ltd.) are dissolved in 40 parts of methyl ethyl ketone. To this is added 40 parts of a 10% solution of dicyandiamide in dimethylformamide (i.e. 4 parts of dicyandiamide) and 2-ethyl-4-
0.1 part of methylimidazole was added and stirred to form a uniform varnish. Manufacturing of prepreg: AS7628/308 for the varnish
(Glass cloth made by Asahi Siebel Co., Ltd.) was immersed in the 165
It was dried in an oven maintained at ℃ for 6 minutes to obtain a semi-cured glass cloth base epoxy resin prepreg. Note that the resin content of this product was 40.3%. Attachment of antibacterial agent: 50% of PCM to the prepreg
% acetone solution was sprayed so that the proportion of PCM was 0.5% based on the resin content in the prepreg. This prepreg was left at room temperature to volatilize the acetone. Molding: 8 sheets of prepreg coated with antibacterial agent were stacked, and electrolytically treated copper foil with a thickness of 0.035 mm was placed on top and bottom of each sheet, one sheet at a time, with the treated side facing the prepreg side, and heated to 170℃. Sandwiched between heating plates, 45
A copper-clad laminate was obtained by heating and pressing at a pressure of Kg/cm ² for 70 minutes. Example 2 Manufacture of varnish: 100 parts of Epicote 1045 (brominated epoxy resin manufactured by Ciel Chemical Co., Ltd.) is dissolved in 40 parts of methyl ethyl ketone. To this were added 40 parts of a 10% solution of dicyandiamide in dimethylformamide (ie 4 parts of dicyandiamide) and 0.1 part of 2-ethyl-4-methylimidazole and stirred to form a uniform varnish. Manufacture of prepreg: A prepreg was obtained in the same manner as in Example 1. Attachment of antibacterial agent: 50% of PCM to the prepreg
% acetone solution to the resin content in the prepreg.
It was sprayed so that the percentage of PCM was 1.5%.
This prepreg was left at room temperature to volatilize the acetone. Molding: A copper-clad laminate was obtained in the same manner as in Example 1. Comparative Example 1 The prepreg of Example 1 to which no PCM was attached was used and molded in the same manner as in Example 1 to obtain a copper-clad laminate. Comparative Example 2 The prepreg of Example 2 to which no PCM was attached was used and molded in the same manner as in Example 2 to obtain a copper-clad laminate. Characteristic tests were conducted on the copper-clad laminates manufactured in Examples and Comparative Examples, and the results shown in Table 1 were obtained.

【table】

[Table] As shown in Table 1, the copper-clad laminate according to the present invention has significantly improved bacterial resistance. It can be seen that the antibacterial resistance is improved, and the soldering heat resistance, peel strength, bending strength, electrical properties, and chemical resistance are at the same level as the comparative example.

Claims (1)

[Claims] 1 A prepreg is obtained by impregnating a base material with thermosetting resin varnish and drying it, then spraying a p-chloro-m-xylenol solution on the surface of the prepreg and drying at a low temperature of 50°C or less to reduce the resin content in the prepreg. 1. A method for producing a laminate having antibacterial properties, which comprises depositing p-chloro-m-xylenol in a proportion of 0.1 to 2.0% by weight, and then laminating prepregs and heating and pressurizing them.