JPH0197636A - Manufacture of glass fiber reinforced laminated plate for electrical use - Google Patents

Abstract

PURPOSE:To facilitate operation by preventing breaks during a continuous manufacture, by specifying the tensil strength of glass paper with respect to the crosslinkable monomer in a setting unsaturated resin liquid to be impregnated. CONSTITUTION:A base material containing glass paper is impregnated with setting unsaturated resin liquid under continuous carriage and jointed, and cut after the laminate of a cover sheet and/or metal foil for continuous setting. The tensile strength of glass paper used should by 0.5kg/15mm or more to the crosslinkable monomer of the setting unsaturated resin liquid to be impregnated. For enhancement of the resistance of glass paper to the crosslinkable monomer, epoxy resin excellent in flux resistance is used as the binder, and its amount should be 1-50pts.wt. per glass paper 100pts.wt. The basis weight of the glass paper is 10-200g/m<2>, and one or more layers are used for the inner side according to the thickness.

Description

[Detailed description of the invention] Chikugori! The present invention relates to a method for continuously manufacturing a glass fiber reinforced electrical laminate using glass cloth as the outermost substrate and glass paper or cellulose-mixed glass paper as the intermediate substrate. Here, the electrical laminate refers to an insulating laminate used as a substrate for various electrical and electronic components, and a metal foil-covered laminate used as a printed circuit board.

In recent years, requirements for the quality of laminates used in consumer and industrial electronic devices have become increasingly strict, and glass substrates are increasingly being used.

Glass substrates include glass cloth, glass paper, glass paper mixed with cellulose, etc., and composite laminates using a combination of these different types of glass substrates have a wide range of uses and are widely used. Conventionally, this composite laminate is made by impregnating glass cloth and glass paper with epoxy resin varnish, then constructing a prepreg, and forming a large number of these sheets, or further adding metal foil,
For example, it is manufactured by stacking electrolytic copper foils, laminating them in a heated and pressurized press, and curing them.

On the other hand, JP-A-55-4838 and JP-A-56-9813
No. 6, etc., discloses a continuous manufacturing method for electrical laminates, and this method allows the laminate to have a more uniform thickness than the conventional pressing method, and has higher productivity. This method involves individually impregnating a plurality of base materials with a curable resin liquid while continuously conveying them in parallel, stacking and combining the impregnated base materials to form a cover sheet and/or
Alternatively, it consists of a continuous process such as laminating metal foil, curing it continuously, and then cutting it. When manufacturing composite laminates, glass paper is placed on the inside, but in a continuous manufacturing method that is virtually pressureless, the thickness of the glass paper corresponds to the thickness of the product at a ratio of 1:1. The thinner the glass paper is, the smaller its basis weight becomes, making it more likely to break during transportation. In addition, when glass paper is impregnated with a curable unsaturated resin liquid that is suitable for continuous production and is liquid itself and does not generate reaction by-products during curing,
The crosslinkable monomer deteriorates the binder of the glass paper, which also causes inconveniences such as the base material being easily broken during transportation.

Therefore, in the present invention, a base material containing glass paper is impregnated with a curable unsaturated resin liquid while being continuously conveyed, and the impregnated base materials are combined to form a cover sheet and/or In a method for producing glass fiber reinforced electrical laminates in which metal foil is laminated, continuously cured and then cut, the tensile strength of the glass paper is greater than the crosslinkable monomer in the curable unsaturated resin impregnated with. This is a continuous manufacturing method for a glass fiber reinforced electrical laminate, characterized by using glass paper having a hardness of 0.5 kg/mm or more.

In carrying out the present invention, the tensile strength of the glass paper used is 0.5 kg/15 mm or more based on the crosslinkable monomer in the curable unsaturated resin impregnated. Except it's paper. Japanese Patent Publication No. 55-4838, No. 56
-98136 etc. can be used. In particular, curing under substantially no pressure is preferable because the equipment and the like are simple.

Glass paper is a long sheet made by dispersing glass fibers with a thickness of 1 to 20 μm in water and making it wet using a binder such as acrylic resin, polyvinyl alcohol, epoxy resin, or melamine resin. It does not matter if it contains synthetic fibers such as paper or polyester, racon, asbestos, rock wool, etc. In the continuous manufacturing method where the glass paper is virtually pressureless, its thickness corresponds approximately 1:1 to the thickness of the product, so the thickness of the commonly used electrical laminate is 1.6 w. Considering the following,
Is the basis weight 10 to 200g/n? , more preferably 20
~1 o o g/rrr, and I on the inside depending on the plate thickness.
N or several layers can be used.

As a method of increasing the tensile strength of the glass paper with respect to the crosslinkable monomer in the curable unsaturated resin for impregnation, the base material is continuously conveyed and before being impregnated with the curable unsaturated resin liquid, In order to improve the dimensional stability of the glass paper base layer, which is the core part, at the same time, it is treated with an epoxy binder that is highly resistant to crosslinking monomers, or at the same time,
An inorganic filler material may be attached, and this treatment can prevent the glass paper from breaking even if it is impregnated with a curable unsaturated resin liquid in a later step.

In addition, in order to increase the resistance of glass paper to crosslinking monomers during wet papermaking in advance, it is effective to use an epoxy resin with excellent solvent resistance as a binder. Bisphenol type epoxy, cresol novolac type epoxy,
Examples include phenol novolac type epoxies. At this time, the binder may be a combination of the above-mentioned binder after papermaking and the epoxy resin binder during papermaking. That is, if either of the binders used has solvent resistance, the resistance to the crosslinking monomer will improve, but it is more preferable if both the binders used during and after papermaking have solvent resistance. The tensile strength of glass paper relative to the crosslinkable monomer increases in proportion to the amount of binder, making it difficult to break. - On the other hand, if the amount of binder is too large, problems such as poor dimensional stability, deterioration of electrical properties due to moisture absorption, and discoloration will occur when used as an electrical laminate. The amount is preferably from 1 to 50 parts by weight, more preferably from 5 to 30 parts by weight.When making glass paper by wet process, if the basis weight is the same and the fiber length is constant, the thickness of the glass fibers is The smaller the number of points of contact between the glass fibers, the higher the strength of the base material due to the binder bonding.In virtually pressureless continuous manufacturing methods, if the product is thin, the thickness of the glass paper used The glass fibers become thinner and more likely to break (thus, it is advantageous for the glass fibers to be smaller in thickness.

Glass cloth is a cloth in which 50 to 800 glass filaments (usually about 9 μm in thickness) are woven vertically and horizontally in various weaving methods such as satin weave, plain weave, open weave, and twill weave. It is a general term for In the present invention, one layer of such glass cloth is used on each outer side of the circle. In order to improve the adhesion of this glass cloth to the curable unsaturated resin used for impregnation, it is preferable to pre-treat it with a resin that has higher adhesion to glass fibers than the impregnating resin before impregnation.

The curable unsaturated resin refers to one in which the resin before curing contains a radically polymerizable carbon-carbon double bond unsaturated group and is cured by a radical polymerization reaction of the unsaturated group. Unsaturated polyester resin is a typical example, but other examples include epoxy acrylate resin, polyester acrylate resin, urethane acrylate resin, spiran resin, and diallyl phthalate resin. These resins can also be rendered flame retardant by containing halogen atoms, especially bromine, bonded to their backbones. Flame retardation can also be achieved by adding additive halogenated flame retardants to halogen-free resins. Since these flame-retardant unsaturated resins themselves are known, detailed explanations will be omitted.

Examples of crosslinking monomers in curable unsaturated resins include vinyl monomers, and styrene is common;
Examples include methylstyrene, vinyltoluene, chlorostyrene, divinylbenzene, carbon 1) (alkyl acrylate having 1 to 10 carbon atoms, alkyl methacrylate having 1 to 10 carbon atoms, diallyl phthalate, etc.), and each can be used in combination.

Furthermore, adding an inorganic filler to the curable unsaturated resin is a known method of increasing the dimensional stability of a composite material, and can also be applied to the present invention. Here, the inorganic filler used is water-insoluble and insulating. Examples include metal oxides such as silica, alumina, zirconia, titanium dioxide, and zinc white, metal hydroxides such as magnesium hydroxide and aluminum hydroxide, talc, kaolin, mica, wollastonite, and clay minerals. Examples include natural minerals, insoluble salts such as calcium carbonate, magnesium carbonate, barium sulfate, and calcium phosphate.

As a measure of the ease with which the glass paper breaks when the glass paper is conveyed in a continuous production method and impregnated with the curable unsaturated resin liquid, the crosslinkable monomer in the curable unsaturated resin is The glass paper was cut to a width of 15n+, immersed for 5 minutes, and the tensile strength was measured while wet according to JIS P-8135. The measurement conditions at this time were a chuck distance of 1001) and a pulling speed of 100 m/min.

In the continuous manufacturing method, when a plurality of base materials are laminated and combined, the running is controlled so that the positions of the ends do not shift. For this reason, it is necessary to apply tension to the base material, and at the same time it is necessary to withstand the weight of the curable unsaturated resin for impregnation. For this reason, if the tensile strength of the glass paper when immersed in the crosslinkable monomer is 0.5 kg/15 mm or more, it will not break in the continuous manufacturing method and will be easy to operate.

The present invention will be explained in detail below with reference to Examples.

Example 1 Base material layer has a thickness of 180. czm, basis weight 210
g/rrf glass cloth is used, and the basis weight is 35 in the middle.
g/n? Three layers of glass paper using 14 parts by weight of phenol novolac epoxy as a binder (100 parts by weight relative to glass fiber) were used, and 18 μm thick copper foil coated with epoxy adhesive to a thickness of 40 μm was stretched on both sides. A 6N double-sided copper-clad unsaturated polyester laminate was produced by a continuous process.

As the resin liquid for impregnation, 100 parts by weight of a flame-retardant unsaturated polyester resin (bromine content: 14% by weight), 4M% of antimony trioxide, 1 part by weight of benzoyl peroxide, and 50 parts by weight of aluminum hydroxide were uniformly mixed. A liquid resin was used.

While each base material is continuously conveyed, it is individually impregnated with the curable resin liquid, then combined, and after laminating copper foil on both sides, it is continuously passed through a tunnel type curing furnace.
It was heat cured at 150°C for 15 minutes and 150°C for 10 minutes.

Example 2 Glass paper with a basis weight of 35 g/rd and using 7 parts by weight of acrylic resin as a binder (100 parts by weight of glass fiber) was coated with 100. Weight part, epoxy binder 4
A double-sided copper-clad laminate having a thickness of 1.6 mm was produced by the same procedure as in Example 1, by immersing it in a treatment solution in which part by weight was dispersed as an emulsion, drying it at 150° C. for 5 minutes, and transporting it.

Example 3 Tsubo! A double-sided copper-clad laminate with a thickness of 1.6 mm was manufactured using glass paper using 60 parts by weight (based on 100 parts by weight of glass fiber) of phenol novolak epoxy as a binder at 35 g/rrr in the same manner as in Example 1.

Comparative Example 1 A double-sided copper-clad laminate having a thickness of 1.6 mm was manufactured using the same glass paper as in Example 2 and the same operations as in Example 1 without epoxy binder treatment.

(Margin below)

Claims (4)

[Claims] (1) Multiple rows of substrates with glass cloth on both outsides and glass paper on the inside are continuously conveyed in parallel, and the reaction by-products are individually delivered to the substrates in a liquid state during curing. Electrical use, which includes the process of impregnating a curable unsaturated resin liquid that does not generate any In the method for producing a laminate, the glass fiber has a tensile strength of 0.5 kg/15 mm or more relative to the crosslinkable monomer in the curable unsaturated resin liquid impregnated with the glass paper. Continuous manufacturing method for reinforced electrical laminates. (2) The method according to item 1, wherein the binder of the glass paper is an epoxy resin. (3) The method according to item 1 or 2, wherein the amount of binder in the glass paper is 1 to 50 parts by weight per 100 parts by weight of the glass paper. (4) The basis weight of glass paper is 10 to 200 g/m
The method according to any one of paragraphs 1 to 3, which is ^2.