JPH011537A - Continuous manufacturing method for electrical rigid laminates - 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]

The present invention relates to a method for continuously producing a laminate and a metal foil-clad laminate in which sheet-like substrates impregnated with a thermosetting resin are superimposed. In particular, it is aimed at metal foil-clad laminates used in laminated insulating boards and printed circuit boards used in electrical applications. In the present invention, the term "laminate" is used to refer to both a laminate, which is often used as an insulating plate without metal foil laminated on its surface, and a metal foil-clad laminate. The laminate has excellent heat resistance against soldering temperatures up to 260°C, excellent electrical insulation properties, dielectric properties, punching processability, chemical resistance, peel strength of metal foil, and surface smoothness of the laminate. It is required that no harmful volatile substances with odor or toxicity are emitted during heating. Furthermore, it does not produce large troublesome warps during printing or heating processes, does not contain air bubbles that impair thermal conductivity and degrade quality, has excellent dimensional stability under various environments, and is low cost, among many other benefits. The shape of the laminate that requires the following characteristics is, for example, a thickness of about 0.5 tm to about 5 tm,
The practical size is usually about 1 m square, and it is a plate-like object with a smooth surface. Conventionally, these laminates were made by impregnating one base material with a varnish made by dissolving resin components in a solvent, then drying the solvent to create a prepreg, which was then cut to a certain size and then laminated in multiple layers in a batch process. It was manufactured using methods such as pressurizing and heating. In this conventional method, the prepreg must be non-adhesive due to workability and process constraints, which limits the resin component and requires a solvent, which requires a complicated manufacturing process. The reality is that there is a big problem with productivity. In addition, conventional metal-clad laminates are made by, for example, impregnating a base material with a varnish in which a resin component is dissolved in a solvent, then drying the solvent to create a prepreg, which is cut to a certain size, and then It was produced by a batch method in which adhesive-coated metal foil, which had been previously coated with adhesive and baked in the B state, was layered on top of the multiple layers of metal foil, and then heated and pressed. These products are used, for example, as circuit boards for printed wiring, but the fact is that the process is complicated, and because they are produced in batches, they require manpower and pose a major problem in productivity. In recent years, from this point of view, several proposals have been made to continuously produce laminates or metal foil clad laminates (U.S. Patent M 3.236.714, U.S. Patent No. 4).
．． 012.267, JP-A-53-88872). However, all of them have the following eight problems, and the advantages of continuous production methods cannot be fully utilized in terms of cost and characteristics, and the current situation is that they have not been fully put into practical use. That is, 3. When using a solvent-based resin varnish that requires a drying process, the resin component that is attached to the substrate after drying usually becomes an extremely highly viscous semi-fluid or solid. Since the surface of the base material to which such a resin component is attached is not a mirror surface, when multiple layers of the base materials are stacked, voids or air bubbles are formed between the layers. To eliminate these voids and bubbles,
Lamination requires heat and considerable pressure, and extremely difficult equipment is required to maintain such high pressure during the curing process. Additionally, drying process lids require drying ovens and solvent recovery equipment, reducing their advantages over conventional lids. b. Also, when using a mature curing resin that generates reaction by-products such as gas and liquid during the curing reaction process, even if it is a resin liquid that does not require the drying process as described above. , a similar difficulty exists in that pressurization must be maintained during the curing process in order to avoid adverse effects such as foaming due to generated by-products. Difficult issue 1: Pressure must be maintained during the curing reaction process for the molded product that is continuously transported.
On the other hand, it is easy to conceive of a compromise solution of arranging local pressurization, such as installing a large number of pairs of heated pressure rolls in series. However, according to the experiments conducted by the present inventors, in such a method, the pressure applied to any fixed point of the molded body fluctuates periodically, causing internal bubbles to swell and other characteristics. No eroded laminate is obtained. Furthermore, applying pressure periodically to an uncured state where the resin component is in a fluid or semi-fluid state due to heating causes unnecessary flow of the resin component, resulting in a corrugated surface, making it almost impossible to obtain a desired product. It's impossible. Therefore, a highly rigid plate-like material such as an iron plate was continuously supplied between the molded body and the pressure roll to solve the problems of local pressurization and pressure fluctuations, but this method had the disadvantage of requiring a complicated device. The weight ratio of the thermosetting resin liquid impregnated and adhered to the base material to the base material is an important issue in quality design of the laminate. However, in the present invention, as will be described later, the curing or molding of the laminated base material is performed under no pressure conditions. There is no way to remove it. However, at the time when sheet-like or film-like coatings are laminated on both sides of the resin liquid-impregnated base material laminate, the weight ratio of the resin liquid amount of the resin liquid-impregnated base material before curing is less than 10% of the base material. So,
A plurality of sheet-like base materials do not bond well even during curing, and therefore, localized peeling occurs after curing, or the base materials sometimes separate into pieces. Even in such extreme cases, the products were often unsatisfactory in terms of heat resistance and mechanical strength due to insufficient effectiveness as a composite laminated material of resin and base material. The weight ratio of the resin liquid amount of the resin liquid-impregnated base material is expressed by the ratio of the weight of the impregnated resin liquid to the weight of the resin liquid-impregnated base material. If the weight ratio of the thermosetting resin liquid to the base material exceeds 90%, in the process of continuously curing the fit layer under no-pressure conditions, there may be areas where curing has not progressed sufficiently, especially in the first half of the process. If the base material does not have sufficient resin liquid holding capacity, the resin liquid will suddenly flow out from both edges of the fill 11 or sea 1~ shaped coating, and the required weight ratio of the resin liquid amount will be reduced. We cannot allow it to become impossible to secure
There was a problem in that the resin liquid that flowed out contaminated the inside of the curing furnace. In addition, at such a high resin liquid ratio, the base material is unevenly distributed in the obtained laminate, resulting in a homogeneous one. )There is a difficult problem. If highly porous substrates are used to achieve even higher resin ratios, such substrates will have Il! Many materials have high mechanical strength, and in continuous manufacturing methods such as the present invention, the long substrates often break during the process of continuous conveyance, and even if a temporary product is obtained, the inside of the laminate is The reinforcing effect of the base material was not sufficient, and in many cases, the mechanical strength was particularly insufficient. The method of the present invention essentially involves impregnating a sheet-like base material with a thermosetting resin liquid that does not require drying and generates almost no reaction by-products such as gas or liquid during the curing reaction process. A laminate is continuously produced by continuously conveying a plurality of sheets of material, then continuously laminating (overlapping) them, and curing them continuously and under no pressure. Furthermore, in the method of the present invention, at the time when the film-like or sheet-like coating is laminated on the resin liquid-impregnated base material laminate, the impregnated base material (i.e., the base material impregnated with the resin liquid).
The weight ratio of the resin liquid to the
It is characterized by carrying out a step of adjusting it within a range of 0 to 70%. The following method can be used to adjust the weight ratio of the thermosetting resin liquid. (Left below) λ, When impregnating a film or sheet-like substrate with a thermosetting resin liquid, an excessive amount of resin is supplied in advance to the impregnating device so that the excess resin liquid adheres to the surface of the substrate. In the process of continuously conveying a plurality of base materials, each base material is passed through a slit field (Fig.
After scraping off the excess amount of persimmon fat and adjusting the amount of adhering resin liquid by adjusting the J play, the laminating device (3)
The base materials are laminated. b. A squeezing roller (Fig. 4) is provided between the impregnating device (2) and the laminating device (3), and the roller (Fig. 4) is used to collect the tea scoop impregnated with excess resin liquid. After squeezing out the resin liquid and adjusting the amount of impregnated resin liquid appropriately,! The material is sent to the A-layer device (3) for lamination of base materials. C0 When a plurality of resin liquid-impregnated base materials are milled using a layering device composed of a pair of rollers or a combination of a roller and a blade (Fig. 1, Fig. 4 to Fig. 6), the distance between the rollers or The distance between the roller and the blade can be adjusted, and by adjusting the lamination interval, excess resin liquid in the resin liquid-impregnated base material is removed, and the resin liquid is laminated while maintaining an appropriate amount of resin liquid. d. A laminating device (2) (Fig. 4) consisting of a pair of rollers is provided on the exit side of the laminating device (3), and when laminating the coating on both sides of the laminated base material, the distance between the rollers in the laminating device area is By adjusting the distance f, the coating can be laminated while removing excess resin liquid from the laminated base material. e. By combining methods 3 to d above, excess resin liquid is removed in several stages, and a laminate with an appropriate amount of resin liquid is finally obtained. E. Continuously conveying the resin liquid-impregnated base material five times; Continuously laminating the base materials; Continuously conveying the laminated base material to a laminating device; Laminating the coating on the laminated base material. In one or more of the steps, a thermosetting resin liquid is supplied to the surface of the film-like or sheet-like base material or the surface iζ where the laminated base material and the coating are laminated, by a device 1351 (FIG. 4). 1. Therefore, the resin liquid is supplied separately and the weight ratio of the resin liquid to the base material is adjusted appropriately. By combining one or more of the methods g and a%e with the method f, the amount of resin liquid impregnated into the laminate f is finally adjusted to the optimum amount. The above-mentioned thermosetting resin liquid does not contain a solvent component that is essentially unnecessary for curing, and the main component is a thermosetting resin in which the entire Al fat component becomes a component of the thermoset product. It refers to a resin liquid that does not substantially generate reaction by-products such as condensed water or carbon dioxide gas during curing. For example, it is unsaturated polyester resin, vinyl ester resin, epoxy acrylate resin, diallyl phthalate resin,
These are radical-containing type or addition reaction type such as epoxy resin liquid. Therefore, for example, condensed citron resins containing phenolic resins, melamine resins, etc. as main components are excluded in the present invention. Note that the thermosetting resin may contain materials for advancing curing as usual. For example, if the resin liquid is an unsaturated polyester resin liquid, it may contain polymeric monomers for crosslinking. In the case of epoxy resin and other resin liquids, it contains a curing agent. In order to finish the surface layer of the laminate well, the method of the present invention blocks oxygen in the atmosphere to ensure good curing when the samurai contains a curing catalyst in the form of a thermosetting thin film or a radical release type. To do this, simultaneously with lamination or after lamination, a film or sheet-like coating is impregnated with a resin liquid and laminated on both sides of the base material.The surface of the laminate may be unevenly laminated if necessary. After one piece of resin is cured, it is peeled off by winding or the like, and the peeled off coating is collected and reused, which is preferable since it is possible to reduce the manufacturing cost of the laminate. When manufacturing a single-sided or double-sided metal foil-clad laminate, by laminating a metal foil that is not intended to be peeled off as a coating on one or both sides of the laminate, the coating can be cured by the surface coating of the laminate. It not only promotes the product, but also makes it a very logical component of the product. In the continuous production of laminates, the present invention is designed to provide a method for manufacturing laminates according to the properties, intended use, and manufacturing conditions required for the product before impregnating the sorted base material with thermosetting resin liquid. In this method, a sheet-like base material is subjected to an appropriate pre-impregnation process and, if necessary, a drying process is added after the pre-impregnation process. In particular, when impregnating a cellulose base material with unsaturated polyester alm ffl during the impregnation process, the base material is pre-impregnated with a solution of an N-methylol compound, and the solvent is removed by drying. By doing so, it is possible to complete a 4A electrical laminate with excellent properties even when moisture is absorbed. The method of the present invention also includes impregnating a sheet-like base material with a thermosetting resin liquid. At this time, the resin liquid is subjected to a vacuum treatment in an environment below atmospheric pressure, and then ladled or under reduced pressure. This method impregnates a sheet-like substrate with an aliphatic compound, shortens the impregnation time of the resin liquid, and almost completely eliminates the incorporation of air bubbles into the product. The present invention further makes it possible to cut the laminate with a cutter when heating the sheet-like substrate impregnated with the thermosetting synthetic resin liquid and proceeding with the curing process continuously and under virtually no pressure. In addition, if the coating laminated on the surface of the laminate is an obstacle (in the initial cured state that is hard enough to be peeled off), cut it to a practical size and continue to cure it by 1 ciA after cutting.
This is a method that can reduce warpage and residual strain of the laminate due to curing to a practically acceptable level. The present invention uses a thermosetting resin liquid that essentially does not require drying and generates hardly any reaction by-products such as gas or dispersion during the curing reaction process. Compared to the method of impregnating a resin varnish, a drying device or a solvent recovery device for the resin varnish is not required, and the properties of the resin liquid are substantially unchanged from the impregnation step to the lamination step (summer joining process of multiple sheets of impregnated base material) R5. It remains unchanged. For example, a craftsman might lay down a sheet-like base material sufficiently impregnated with a resin liquid, and when the resin liquids come into contact with each other, (the degreasing material has a low viscosity, It is possible to suppress the dust generated in the tube to the minimum level, and there is no need to apply special heating or knife pressure during the layering process. Because there is no such thing as heat-hardening, it is possible to produce products with excellent properties at low prices without the need for difficult and unrealistic equipment to apply and maintain high pressure as described above. The present invention has the advantage that it can be manufactured by impregnating a sheet-like base material with a thermosetting
The fact that it was possible to continuously manufacture hard products (products with excellent properties by heating) under no-pressure conditions is nothing short of a masterpiece. Necessary product distortion can be eliminated, and products with excellent dimensional stability during heating, especially in the thickness direction, can be manufactured. If pressure is applied during hardening, the inner layer soaked in the base material will flow out, which will disturb the uniform distribution of the base material and the fat-resistant layer in the laminate, resulting in a decrease in electrical insulation performance. 7. The present invention does not require any special equipment (because the milling process is carried out under no pressure conditions, so there is no need to apply pressure), and the above-mentioned method of controlling local pressure is unnecessary. δS has excellent surface smoothness! It has the advantage of being able to manufacture products that are The term "no pressure" as used in the present invention means that the operation is carried out under normal atmospheric pressure without artificial pressurization. Regarding ii, when laminating film-like or sheet-like coverings, the TJ! i Receives the weight pressure of the cover. However, the weight pressure is actually 0.01 kg, 'c+a
', usually less than 0.01, margin white y/ctl -0,001I;9/-*,
Such a micro-pressure is used in the present invention without impairing the molding conditions such as flow and outflow of the wood 1ja, and results in improved results. In addition, since the present invention does not require a complicated device that performs continuous heating and pressurization, the heating method and continuous conveyance method during curing can be selected with great care. For example, 3. Using rolls arranged at 1 m intervals as supports for the heating proboscis, hot air is blocked from one or both sides of the roll. b. A method well known as a floating dryer, in which the upper and lower parts of the heating proboscis are A jet stream of heated air is ejected from l, and it is conveyed while floating in the air. It is propelled over the heating plate by C9 heat medium and °4 heat, and heat transfer from 1 to n0 heat, O d, heat medium and 4 heat. Heating is done using a heating plate or radiant heat from the heating proboscis. In both cases, unnecessary pressure is eliminated and the material is heated and cured.
This is a preferable method that involves continuous conveyance. The laminate manufactured by the uninvented method has superior product thickness accuracy compared to the product number manufactured by the North American method using the traditional batch method. For example, if you take a laminate with a thickness of 0.511I11 and use the conventional method, the variation range of thickness will be 70 to 160.
However, in general thickness according to the present invention, the thickness varies by at most 20 to 30 μ. Moreover, the thermal expansion coefficient in the thickness direction is 40 to 60% of the mature expansion coefficient of the laminate produced by the Takumi method. Furthermore, it is significantly superior in terms of lower manufacturing costs, higher manufacturing speeds, and simpler equipment. The present invention is as shown in FIG.
To the sheet-like base material (6) which is sent from 3g inkstone,
Continuous drying equipment uz, impregnation equipment jit t21, loading equipment (
3), Continuous heat curing furnace (4), Drawer temperature Ni t13)%0
The cutting devices (5) are arranged in sequence, and the continuous thermosetting furnace (4) is equipped with a U
The laminate (7) is manufactured continuously without any O-pressure handle. The sheet-like base material (6) referred to in the present invention is a conventional laminate 1ζ
The same base materials as those used can be used, such as glass fiber cloth, glass non-woven cloth, etc., paper made from cellulose fibers such as kraft paper and linter paper, and non-acupuncture materials such as asbestos cloth. Refers to a sheet-like or band-like material made of quality fibers. When paper is used as a sheet-like base material, from the viewpoint of impregnability and quality, the density (bulk ratio ■) when air-dried is 0.3 to 0.
．． Paper made of living cellulose fibers, such as kraft paper, having a molecular weight of 7 g/d is preferable. Before being impregnated with the thermosetting resin liquid, the sheet-like base material is subjected to an appropriate pre-synthesis process and, if necessary, a drying process, depending on the characteristics required for the product, usage, manufacturing conditions, etc. In this case, a sheet-like base material that has undergone pre-impregnation treatment may be stored in the base material supply section (1). Or bleed impregnating device-J bleed and if necessary l! J! The dry hemp paste is placed in front of the hardening ladle impregnating device (2), and the base material supply section is placed against the sheet-like base material (6) fed from ). Pre-impregnation can be carried out arbitrarily. The continuous drying device IUZ is installed to remove the solvent when pre-impregnation is performed with a solution S using a solvent in the pre-impregnation device t1411ζ. If the pre-impregnation is carried out by impregnation of a liquid compound without a solvent or adsorption of a gaseous compound, the drying device may be omitted if not required. The pre-impregnation process includes the following treatments, but this IC
(Of course, this is not limited to the characteristics of the base material and may be changed depending on the intended use.) (1) If the base material is a glass stone base material, it may be treated by silane coupling cutting. Pretreatment with various coupling agents and surfactants. Impregnation of various thermoplastic resins into the base material for the purpose of modifying the initial properties of the laminate 14) Pre-impregnation with various thermosetting resin solutions (5) Various impregnations
Pre-impregnation with 251-phase fatty acids i6) Impregnation and reaction of reactive compounds with the substrate surface, such as cellulose atylation (7) One of the solutions when using a resin liquid with a short pot life in the impregnation process (8) Impregnation with inorganic filler slurry liquid Among the various pre-impregnations described above, (3 for υ), glass 1B
By pre-treating the Ts material with vinyl alcohol disilane and then impregnating it with an unsaturated polyester resin solution in the impregnation step, a laminate with a bending strength 1.5 times that of one without pre-impregnation is obtained. can be manufactured continuously. +311 (g) For kraft paper, 10% polyethylene glycol is applied to the paper in advance, and then an unsaturated polyester resin liquid is impregnated in the impregnation process, so that the untreated material is (7) For lζS, commercially available polyamide resin for curing evo-gyu resin is coated with a glass cloth base material in advance so that the size and amount are 30% of that of the epoxy resin. By pre-impregnating, drying, and then impregnating with a commercially available epoxy resin liquid in the impregnation process, the problem of resin liquid potripe in the storage tank or impregnation bath can be solved. It is desirable that the amount of impregnation deposited on the base material is 50% or less of the final impregnation fζ, and an excessive amount of pre-impregnation may impair the impregnation of the resin liquid in the next impregnation step. The reason why the impregnation process is important is as follows. When paper mainly composed of cellulose fibers is impregnated with an unsaturated polyester resin liquid, the resulting paper-based unsaturated polyester resin laminate has a Various properties, including electrical insulation, thermal properties of solder, copper foil peeling strength, punching workability,
Although the mechanical strength and the like are extremely good, it suffers from the drawback that the properties as a laminate may deteriorate due to moisture absorption. Although the unsaturated polyester resin itself has excellent electrical insulation, heat resistance, moisture repellency, and water resistance, it has poor adhesion to cellulose, which is the main component of the paper base material.
This is thought to be due to the fact that the interface between the resin and cellulose fibers peels due to moisture absorption, which increases the amount of moisture absorbed and ultimately leads to a decline in various properties. A method of treating with melamine or methylolguanamine (Japanese Patent Publication No. 38-13781), a method of formalizing paper base material with formaldehyde (Japanese Patent Publication No. 40-29189)
), an example in which a cellulose base material was converted into acrylamide methyl ether with N-methylol acrylamide, washed with water and dried, and then diallylphthalate resin was applied (Japanese Patent Publication No. 39-24
121) etc. are known. However, in the method of treating with methylolmelamine or methylonylguanamine and the method of formalizing the paper base with formaldehyde, it is necessary to use a large amount of these treating agents in order to obtain sufficient effects. In addition, the method of converting cellulose into acrylamide methyl ether, as disclosed in Japanese Patent Publication No. 39-24121, requires a long time for the methyl etherification reaction, and also requires a water washing step, etc. Acrylamide methyl etherified cellulose is synthesized through a complicated post-processing process, and laminates are manufactured using it as a base material, but the disadvantage is that the punching processability of the resulting laminates is not good. As a result of repeated research, the inventors of the present application have invented a method that can prevent the deterioration of properties due to moisture absorption S.The method is based on the polymerization monomer used in combination with the unsaturated polyester resin,
For example, an unsaturated polyester resin laminate is manufactured using cellulose as a base material, which is obtained by impregnating a car with a solution of an N-methylol compound having an unsaturated bond as a functional group that is copolymerizable with a vinyl monomer and drying it. As a result, an electrical laminate with excellent properties not only under normal conditions but also when absorbing moisture was completed. Moreover, this laminate can eliminate the various drawbacks of the conventional unsaturated polyester resin laminate described above. Drying is characterized in that it is only necessary to remove water, alcohol, etc., which are the solvents of the N-methylol compound, and there is no need to react the cellulose with the N-methylol compound. The unsaturated polyester resin used in the present invention may be either liquid or solid at room temperature, but one that is liquid at room temperature is particularly preferred. The unsaturated polyester resin liquid is generally well-known and has a molecular structure of, for example, ethylene glycol, propylene glycol, diethylene glycol, 1゜4-butanediol and 1゜4-butanediol. , 5-bentanediol, saturated polybasic acids such as phthalic anhydride, inphthalic acid, terephthalic acid, adipic acid, sebacic acid, azelaic acid, unsaturated polybasic acids such as maleic anhydride and fumaric acid, and glycols such as It is a mixture of crosslinking monomers. Polymerization monomers used as crosslinking monomers are generally styrene, but others include α-methylstyrene, vinyltoluene, chlorostyrene, divinylbenzene, T-alkyl acrylate having 1 to 10 carbon atoms, and carbon number Monomers such as 1 to 10 alkyl methacrylates, diallyl phthalates, triallyl cyanurates, etc. can also be used. The amount of these polymerized monomers used is 20 to 50% by weight of the unsaturated polyester resin. In particular, a mixture of styrene and divinylbenzene has shown good results when copolymerizable or for the purpose of reinforcing the mechanical strength of the resulting product. Furthermore, a general-purpose organic peroxide is added as a curing catalyst, and a curing accelerator is added as necessary during curing. When curing an unsaturated polyester resin liquid, a curing catalyst (polymerization initiator) is usually added. In the case of thermosetting unsaturated polyester (M resin), organic peroxides are generally used, and those described below are preferred. lζ, or a curing catalyst that is sensitive to light alone, or radiation 1
It is of course possible to use known curing catalysts, such as c-sensitive curing catalysts. Although many organic peroxides for curing unsaturated polyester resins are known, the selection of the polymerization initiator is important since the invention relates to the production of new electrical laminates by pressureless molding. Decomposition products of organic peroxides remain in the product, albeit in small amounts. Electrical laminates and copper-clad laminates are usually heated at various temperatures and pressures of about 100°C to 260°C during the processing process, and the above-mentioned decomposition products volatilize during the processing process, causing odor in some cases. This odor is undesirable as it impairs the working environment. According to the ωF research conducted by the present inventor, organic peroxides such as aliphatic peroxides, especially those selected from aliphatic peroxyesters, may be used alone or in combination. We have manufactured an electrical laminate with significantly reduced odor when used. Aliphatic peroxides refer to the following: ROOH, RmM(OOH)n, ROOR, RmM(O
OR')n. RnMOOMR'n, R(CO2H)n, R50200
H. R50200CR1, R50200502R1, R(C
O2Brin. (However, it, R', R#, R/I are aliphatic hydrocarbons, and M is a metal or metalloid.) Specifically, for example, di-t-butyl peroxide, 2
,5-dimethyl-2,5-di(t-butylperoxy)
hexane, acetyl peroxide, imbutyryl peroxide,

The odor of [-butylperoxy-2-ethylhexanoate, etc.] is a human sensuous thing and varies slightly from person to person, so sufficient consideration must be given to the evaluation method. In the present invention, a detailed analysis was carried out by employing a multiperson odor test and a gas chromatograph analysis of odor components. Aliphatic peroxyesters have the following general formula: ]NCOOR1艮SO□OOR' (However, λ and R are aliphatic hydrocarbons, and Ω is an integer from 1 to 4 determined depending on the structure of the skin.) For example, ester, L-butylperoxy-2-ethylhexanoate, t-butylperoxylaureutate, and the like. It is considered that the reason why aliphatic peroxides or peroxy esters are preferable is that aromatic catalytic decomposition products are not present among the volatile components generated during heating. When an aromatic residual peroxide is used, aromatic decomposition products will volatilize, causing odor. The temperature and time conditions for curing the resin liquid vary depending on the organic peroxide used, but in the present invention,
Since molding is carried out under pressureless conditions, curing is preferably started at a temperature of 100°C or less in order to eliminate foaming due to vaporization of the liquid copolymerized monomer at an early stage, and thereafter. A temperature range of 50 to 150°C is suitable. Electrical laminates and copper-clad laminates [In this case, advanced features such as heat resistance, dimensional stability under heating or moisture absorption, punching properties, adhesive strength between the laminate and copper foil, and electrical insulation properties are required. characteristics are required. Therefore, for the purpose of these improvements, various additives, mixtures, fillers, etc. may be added to the polyester resin group, and this does not limit the present invention in any way. The epoxy resin liquid to be impregnated into the sheet-like substrate may be a bisphenol Ag epoxy resin, a novolac type epoxy resin, or a mixture thereof, a mixture containing a reactive diluent as required, and a curing agent. Can be used in combination. It is preferable to use a liquid type epoxy resin. As the curing agent, any well-known hardening type or amine curing type can be used. In particular, in the present invention, when an epoxy resin liquid consisting of an epoxy resin and an acid anhydride curing agent is used, the viscosity of the resin liquid is adjusted to a viscosity suitable for impregnating the base material, that is, a viscosity of 8 times 0 at 25°C.
．． It is suitable that it can be set to 5 to 30 poise, preferably 1 to 15 poise. The curing agents commonly used as epoxy curing agents include various amine-based, amidoamine-based, dicyandiamide, and imidazole-based curing agents, but when using bisphenol A type epoxy resin, which has good physical properties, It is difficult to adjust the viscosity to an appropriate range unless a large amount of dissemination and cutting is used, which is accompanied by a noticeable decrease in physical properties, and in the case of amine-based and amidoamine-based curing agents, the pot life is short. On the other hand, dicyandiamide curing agents and imidazole curing agents have a long pot life, but have the disadvantage of requiring high temperatures and long hours for curing. When using an acid anhydride curing agent, such a drawback does not exist and it is a suitable curing agent for the present invention. More specifically, the epoxy mIll? of the present invention? m I
To be specific, as the epoxy resin, bisphenol A type liquid epoxy resin is suitable, but other epoxies such as bisphenol F5 and novolac type can also be used, and if necessary, solid epoxy plum fat or a diluent can be mixed. You may. As acid anhydride curing agents, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyl tetrahydro(hydrophthalic acid, methyl hexahydrophthalic anhydride, methyl endic anhydride, etc.) can be used, and these Of course, it is also possible to use a mixture.Among them, methyl tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methylendic anhydride, which are liquid at room temperature, are suitable for the method of the present invention.As the curing aid, Commercially available curing aids such as 2-ethyl-
4-methylimidazole, boron trifluoride complex compounds, tertiary amines, benzyl, methylamine, benzyldimethylammonium chloride, tertiary amine salts, etc. can be used. In addition, the sheet-like base material is made of a long glass cloth. In particular, it is preferable to use silane coupling treatment by pre-impregnation as described above. The N-methylol compounds having as a functional group an unsaturated bond that can be combined with a vinyl monomer and used for the pre-impregnation of the present invention include the following. ■, Modified aminotriazine methylol compound. In other words, methylol compounds of aminotriazines such as guanamines or melamine (or compounds in which part or all of their methylol groups are etherified with lower alcohols such as methanol) can be copolymerized with vinyl monomers as a functional group. This is a modified amide/triazine methylol compound with an unsaturated bond introduced. For example, a partial ester compound of an unsaturated carboxylic acid such as acrylic acid or itaconic acid and a methylol compound of aminotriazine; or a partial ether compound of an unsaturated alcohol such as allyl alcohol and a methylol compound of aminotriazine; or acrylamide, methacrylamide, etc. A condensation product of an unsaturated carbonamide and a methylol compound of aminotriazine; or a condensation product of an epoxy compound having an unsaturated group such as glycidyl methacrylate and a methylol compound of aminotriazine. ■, General formula % Formula % (However, R1 amount ■ (or CH3R2=H or C, ~3
It is an amidomethylol compound represented by (alkyl group), among which,
N-methylol acrylamide, N-methoxymethylol acrylamide, N-butoxymethylol acrylamide, N-methylol methacrylamide,
Preferred are N-methoxymethylol methacrylamide, N-butoxymethylol methacrylamide, and the like. One or a mixture of two or more of these or a co-condensate of two or more of these may be used. Furthermore, in addition to (I) and (6) above, instead of the methylol compound of the modified aminotriazine described in (I) above, it also includes a mixture of melon and the following a and b. 3. N-methylol compounds such as aminotriazine methylol compounds that do not have as a functional group an unsaturated bond that can co-combine with vinyl monomers, N-methylol compounds, and modifiers for the N-methylol compounds, i.e., aJjl N-methylol compounds. A compound that has as a functional group an unsaturated bond that can be combined with a group that can be condensed with or added to a vinyl-luminium compound, such as an unsaturated carboxylic acid such as acrylic acid or itaconic acid, or an unsaturated bond such as allyl alcohol. It is also an embodiment of the present invention to impregnate and dry a paper base material with a solution of a mixture of alcohol, or an unsaturated carbonamide such as acrylamide or methacrylamide, or an epoxy compound having an unsaturated group such as glycidyl methacrylate. (I). Almost the same effect as in the case of impregnation with the treatment agent of type (6) can be achieved. This is due to the reaction between the methylol compound of aminotriazine described in item (3) and the modifier described in item (b) during drying of the treated paper or subsequent impregnation and curing of the unsaturated polyester resin. The main purpose of the present invention is to improve the adhesion between the unsaturated polyester resin and the paper base material and to prevent the deterioration of various properties when moisture is absorbed. In order to achieve this effect, it is necessary to use the above-mentioned (I) and (II) as treatment agents for paper base materials.
As shown in (2), a compound having both an N-methylol group capable of bonding with cellulose and an unsaturated bond as a functional group that can be copolymerized with a polymerizable vinyl monomer that is a crosslinking agent for unsaturated polyester resin is used. or (as shown in IIDI), an N-methylol compound that does not have as a functional group an unsaturated bond copolymerizable with a vinyl monomer, and a modifier for an N-methylol compound that has an unsaturated bond. It is necessary to use a mixture of these.If these are treated with a compound having only one functional group, either an N-methylol group or an unsaturated bond copolymerizable with a vinyl monomer, The effect is not sufficient. For example, when treated with methylolmelamine having only N-methylol groups, or with acrylamide having only unsaturated bonds, when the resulting laminate absorbs moisture, The various performances were not satisfactory.The concentrations of the treated solutions shown in (1) to (III) above used in the present invention are the same as those for the paper base material after drying (i.e., only for the paper base material).
The adhesion amount is 3 to 30 parts by weight, preferably 6 to 20 parts by weight.
It is desirable to apply tli[ to 3 parts by weight. If the amount is less than 3 parts by weight, the effect will not be sufficient, and if it exceeds 30 parts by weight, the plate will become brittle when made into a laminate and the punching workability will deteriorate. let As a solvent for dissolving these processing agents, solvents such as water, alcohols, ketones, and esters can be used. In addition, in order to efficiently advance the etherification reaction between cellulose and the N-methylol group of the above-mentioned treatment agent, it is effective to add an acidic condensation catalyst or to increase the curing temperature of the paper after impregnation treatment. . By such a method, it is possible to partially induce the etherification reaction of the cellulose prior to the subsequent impregnation and curing reaction of the unsaturated polyester resin, but the special effect of this reaction, which precedes curing, has not been recognized. In the present invention, it is not necessarily necessary to proceed with the above etherification reaction during the paper processing process (it is not necessary to proceed with the above etherification reaction in the paper processing process). On the other hand, depending on the type of catalyst added, the electrical insulation properties of the resulting plate may be reduced, or the plate may become hard and its punching workability may be degraded. Additives such as a desired combination inhibitor, a polymerization catalyst, a surfactant, a plasticizer, etc. can be appropriately combined and used by adding them to the processing agent bath liquid. A paper base material, or in some cases a cloth base material, which is usually used in the laminate is impregnated using a dipping bath, a roll coater, a spray, etc., and then the solvent is removed by drying to obtain a treated base material. The drying mentioned here only needs to be done to remove the used solvent, and there is no need to react the base cellulose with the treatment agent. Methylolmelamine, methylolguanamine, etc.
Using a paper base pre-impregnated with a methylol compound (only methylol compounds that do not have combinable unsaturated bonds as a functional group),
When a laminate was created using the unsaturated polyester resin according to the method of the present invention and its performance was investigated, it was found that the electrical insulation properties and soldering heat resistance decreased less due to moisture absorption than when no pretreatment was performed. Although there was a considerable improvement in the water occupancy (ml), on the other hand, cracks were likely to occur due to impact, and therefore, the punching workability of this product was not suitable for practical use. It is thought that the influence of the dynamics of the unsaturated polyester resin used is also large, and the present inventor used the pre-treated paper described above to examine many unsaturated polyester resins on the market, but did not find any good results. It has been rare to find any material that has punchability and is practical.In view of the current situation, the present inventors conducted intensive research and found that vinyl monomers used as functional groups in the pretreatment of cellulose base materials were found. Even if known methylol compounds such as methylolmelamine and methylolguanamine, which do not have an unsaturated bond as a functional group that can copolymerize with the body, are used, one methylol compound may be added to the molecule for the purpose of imparting flexibility. a hydroxyl group, a carboxyl group that can be condensed with a methyl group,
By mixing or condensing higher aliphatic derivatives having one or more groups such as amide 7 groups and amide groups, the resulting 411-layer plate solves the above-mentioned drawbacks and has excellent punching workability and moisture resistance. It has been found that an excellent laminate can be obtained. This will be explained in detail below. In the present invention, methylolmelamine and methylolguanamine (that is, methylol compounds that do not have an unsaturated bond as a functional group that can be copolymerized with a vinyl monomer) include melamine, formoguanamine, acetoguanamine,
It refers to initial condensates of guanamines such as propioguanamine, benzoguanamine, and adipodiguanamine and formaldehyde, or those obtained by etherifying some or all of their methylol groups with lower alcohols such as methanol or butanol. Examples of higher aliphatic derivatives that are mixed or condensed with the above-mentioned methylolmelamine and methylolguanamine for the purpose of improving punching processability include the following. i.e. E-wa fatty acids such as caprylic acid, capric acid, lauric acid, myristic acid, valmitic acid, stearic acid;
Unsaturated fatty acids such as oleic acid, erucic acid, linoleic acid, eleostearic acid, and lylunic acid; and esters of the above fatty acids with polyhydric alcohols such as ethylene glycol, polyethylene glycol, propylene glycol, glycerin, pentaerythritol, and sorbitol. and aliphatic amides which are derivatives from fatty acids such as those mentioned above; and saturated or unsaturated higher alcohols such as caprylic alcohol, lauryl alcohol, myristyl alcohol, cetyl alurur, stearyl alcohol, oleyl alcohol, rylyl alcohol, and higher Examples include ethers of alcohols and polyhydric alcohols, and aliphatic amines that are derivatives of higher alcohols. Also, oxyfatty acids and derivatives thereof such as lysyllic acid can be used for the same purpose. The required f-molecule contains a group that can be condensed with the methylol group of methylolmelamine or methylolguanamine, such as a hydroxyl group, carboxyl group, amino group, or amide group, and a long chain that acts to weaken the cohesive force of methylolmelamine or methylolguanamine. A necessary condition for a punching processability modifier is that it also has an alkyl group. The number of higher aliphatic derivatives that meet these conditions is extremely large, but according to the results of studies conducted by the present inventors, when the number of carbon atoms is 8 or more, they are effective as punching processability modifiers. Oleic acid, oleyl alcohol and derivatives thereof, such as oleic acid monoglyceride, which have 18 carbon atoms and one unsaturated group,
It has also become clear that when oleic acid diglyceride, oleic acid amide, and oleylamine are used, the performance of the resulting laminate is well-balanced and is a preferred embodiment of the present invention. By the way, the use of such a modifier depends on the glass transition temperature 1 of the unsaturated polyester resin used in the laminate.
The optimum amount varies but is usually in the range of 3 to 40 parts to 10,041 parts of methylolmelamine or methylolguanamine. How to use it If you have any questions about how to use it, you can either mix the modifier with methylolmelamine or methylolguanamine in the form of a solution or tA tA solution, or use No. IIIJ by condensing it in advance. Good too. In this case, water, alcohols, ketones, esters, etc. are used as learning agents. In addition, the concentration of these treatment agent systems is the same as in the case of N-methylol acrylamide described above, and the total adhesion q to the cellulose fiber base material after drying is 3 to 30 FJHjt.
It is desirable to increase the adhesion so that it is preferably 6 to 20 parts by weight, and the effect is not sufficient if the adhesion amount is less than 5 aia parts. (This results in deterioration of punching processability.) Due to the solution or suspension of the processing agent prepared under the above conditions, cellulose paper bases such as kraft paper and linter paper, and even cellulose materials such as cotton and rayon, are used. Immerse the fabric base material in a bath,
After impregnation using a roll coater or spray, a treated substrate is obtained by drying to remove the solvent. Desirable drying temperature is 70 to 150°C, and drying time is about 1 to 60 minutes. In addition, the unsaturated polyester Tochi fat family used is the same as those mentioned above. The two types of paper pre-impregnation treatments (paper pre-treatment) related to the present invention have been described above. This method [7] has excellent punching workability, but in order to provide excellent low-temperature punching workability, the glass transition temperature of the cured product of the unsaturated polyester resin must be 20 to 80. It is preferable to use a resin at ℃. However, not only in the case of the above-mentioned paper pretreatment, but generally in the present invention, when the glass transition temperature is 20 to 80 °C,
The present inventors have discovered that it has excellent punching workability. When electrical laminates and copper-clad laminates are put into practical use, they are often subjected to stamping, followed by molding and drilling (thus, excellent punching and drilling properties are required). Particularly in recent years, with the miniaturization of electronic components and the increase in the density of circuits, the current situation is that more sophisticated processing characteristics are desired. A laminate has been made by impregnating crystalline polyester or polyester that is solid at room temperature with a crosslinking agent as a solution using a solvent, drying it to form a prepreg, and then molding it under heat and pressure. The resulting laminate has a high glass transition temperature < iff and has excellent thermal properties, but has problems with punching workability, particularly during low-temperature punching, which is usually performed at about 50 to 80°C. (As a result of thorough research, it was found that the difference between the glass transition temperature of a cured product of an unsaturated polyester resin composition and the optimal punching temperature of a laminate made from such a resin composition) should be solved. 1. The punching temperature of the laminate, which has been found to be closely related, is in the range from the glass transition temperature of the cured resin composition to 20°C above the glass transition temperature, particularly preferably from the glass transition temperature to 20°C. It has been found that a temperature range of about 10°C is suitable.Using an unsaturated polyester resin composition in which the glass transition temperature of the unsaturated polyester persimmon fat composition cured product is 20 to 80°C, preferably 30 to 70°C. When a laminate is formed, the processing temperature during punching is in the range from the glass transition temperature of the resin composition @cured product to 20°C, particularly preferably 1.
It was discovered that this material has excellent low-temperature punching workability when heated to a temperature of 0° C., and the present invention has been achieved. The punching workability referred to in the present invention is A S -r M D
517-44 according to the punching workability test method,
Evaluation was made according to the scoring criteria. When all evaluation items Iζ of the end face, surface, and hole were evaluated in the range of excellent to fair, the punching workability was determined to be "good." If you value low-temperature punching properties, use unsaturated polyester 1M1L! The glass transition temperature of the cured composition is 20 to 8.
An unsaturated polyester resin composition having a temperature of 0°C, preferably 30 to 70°C is used. If a material with a glass transition temperature exceeding 80°C is used, low-temperature punching may result in undesirable chipping or worm-eaten edges, cracks or clear protuberances on the edges or around the hole, chipping between poles on the hole wall, or holes. There are two cases where the periphery of the hole has a significant bulge or the hole has a significant taper.When punching is performed at a temperature below 20°C, the periphery of the hole has a significant bulge or taper. In the latter case, although the punching process can be performed better by cooling the test piece than in case 1, it is not practical. Glass transition temperature is 30-70℃
When an unsaturated polyester resin composition in the range of 1 is used, a product with particularly excellent low-temperature punching processability can be obtained. The punching temperature for low-temperature punching type products is usually about 50 to 80°C in related industries, but the present invention can be applied within a wide processing temperature range of about 30 to 80°C. To make it possible to provide various products that can be easily punched. When considering low-temperature punching properties, Fuhiwa polyester resin is determined based on the raw materials used, such as the types of glycols and the copolymerization ratio of these with saturated dibasic acids and unsaturated dibasic acids, as well as the type and type of crosslinking monomer. The properties of the cured resin change depending on the blending ratio, and therefore the properties of the laminate to be assembled also change. The unsaturated polyester resin used for this purpose may be the one mentioned above, but the glass transition temperature of the one mixed with a crosslinking monomer and cured is 20 to 80.
C. Preferably in the range of 30 to 70.degree. C. All combinations are applicable. For example, specifically, an unsaturated polyester diethylene glycol, inphthalic acid, and maleic anhydride with the following composition (molar ratio) = 3:2:1 propylene glycol.
〃 = 1:11.3-butanediol 〃〃 = 1.4-butanediol, inftanei, maleic anhydride = 2:1:1 diglobylene glycol 〃〃 = diethylene glycol
〃 l = 〃Propylene glycol, anhydrous phthalate, maleic anhydride = 〃
〃 Glutaric acid // ==
//〃 Succinic acid 〃=〃 〃 Pimelic acid 〃=〃〃 Adipic acid 〃=〃 〃 Sebacic acid 〃=〃〃 Azelaic acid Maleia anhydride Vg1= ttResin liquid made of 65% of the above unsaturated polyester and 35% of styrene, etc. Among the above resin liquids, propylene glycol: isophthalic acid: maleic anhydride =
The glass transition temperature of the 1-layer resin liquid, which uses a 2:1:1 resin, is approximately 70°C, but as a result of low-temperature punching evaluation of this resin liquid at 75°C, it was found that the low-temperature punching process was extremely superior. It showed workability. In addition, the polymerization monomer as a crosslinking monomer is a general f
This styrene is used, but substituted styrenes such as vinyltoluene, chlorostyrene, dichlorostyrene, and divinylbenzene, vinyl acetate, acrylic esters, methacrylic esters (for example, butyl acrylate, etc.), diallyl phthalate, triallyl cyanurate, etc. Polymerizable esters or a combination of these and styrene may be used, and the cured product of the unsaturated polyester resin composition containing these polymerizable esters has a glass transition temperature of 20 to 80.
℃ Preferably in the range of 30 to 70℃ (just mix as much as possible. For example, unsaturated polyester resin with a composition of diethylene glycol, isophthalic acid, maleic anhydride - 3:2:1, styrene, and butyl acrylate are mixed in the following manner. Examples include resin liquids mixed at the weight ratio shown in Table 1.It is also possible to mix rubber, plasticizers, fillers, and other additives, but it is also possible to mix these in the weight ratio. It is necessary to adjust the cured resin composition so that it falls within the scope of the present invention.Rubbers include maleated polybutadiene and/or copolymers thereof.Plasticizers include ihaftal with adipic acid. These include commercially available ester plasticizers made from acids and glycols, and epoxidized soybean oil.Inorganic materials include calcium carbonate, silicic anhydride, and titanium oxide, which are used as fillers in unsaturated polyester resins. As the base material, the above-mentioned known materials can be used, but a particularly desirable product can be obtained when the base material is used as the base material. Copper-clad laminate is 3
It exhibits favorable punching workability at a processing temperature of 0 to 80°C, and according to the present invention, it solves the drawbacks of conventional unsaturated polyester base laminates, and it also It was also possible to obtain a product with excellent punching workability. In the present invention, when impregnating a sheet-like base material with a resin liquid,
As with the conventional method (compared to the case of impregnating with so-called varnish, which is a mixture with a solvent, sufficient consideration must be given to the problem that the viscosity of the resin liquid to be impregnated is higher. Impregnation equipment (2) E-koha , as shown in Fig. 4 to Fig. 6 (a method in which the substrate (6) is impregnated with resin liquid while passing through a bath containing resin liquid, and a sheet-like substrate conveyed horizontally as shown in Fig. 1). There are curtain flow one-sided methods that supply resin liquid from a nozzle to the top surface of the material (1), and others.Dip type impregnation methods tend to leave air bubbles inside the base material, so care must be taken.Curtain flow one-sided methods The method of impregnating from one side of the substrate, such as Even when the impregnation has progressed macroscopically to the bottom surface, it still contains many air bubbles microscopically, especially when the base material is paper. However, the air bubbles gradually disappear, and then It usually takes 7 to 20 minutes for this to occur. Some of the air bubbles seem to disappear during the curing process, but normally as mentioned above (if the layers are laminated and hardened before the air bubbles disappear, the product will deteriorate). It contains small air bubbles inside, which impairs the thermal conductivity of the laminate, which can lead to undesirable overheating of electronic components mounted on the product and impair the transparency and quality of the laminate. Of course, the impregnating property varies depending on parameters such as pressure, viscosity, wettability (contact angle) between the base material and the resin liquid, time, etc., but it generally takes the form described above.As mentioned above, it is usually 7 to 7. The fact that about 20 minutes of impregnation time is required means that it is necessary to increase the distance that the impregnated base materials are individually transported from the start of impregnation until the resin liquid-impregnated base materials are laminated (superimposed). Alternatively, the overall line speed (conveying speed) may be limited to a low speed.However, for practical use, it goes without saying that it is preferable to secure a faster impregnation speed. Air bubbles are mostly correlated with impregnation conditions and heating and pressure conditions during curing; the longer the impregnation time, the fewer air bubbles inside the impregnated base material, and the higher the molding pressure, the more air bubbles remain during curing. It is said to be advantageous because it dissolves air bubbles into the resin layer. However, long impregnation time and high molding pressure are disadvantageous because productivity decreases and the equipment becomes large. By treating the liquid under reduced pressure, air bubbles in the product can be almost completely eliminated in a short impregnation time and even when the molding pressure during curing is substantially no pressure. According to this method, when compared with the same impregnation method and other methods of the same manufacturing method that do not involve depressurization treatment,
/3 to 1/10 iζ The term "reduced pressure treatment" as used in the present invention, which can shorten the impregnation time, means a treatment in which the resin liquid is exposed to an environment at atmospheric pressure or lower. Therefore, for example, a resin liquid containing a curing catalyst is placed in a pressure-resistant container, and the space inside the container is depressurized. Alternatively, the resin liquid is injected into a vacuum container at any time. Alternatively, the resin-impregnated base material may be temporarily treated in a vacuum container, but the present invention is not limited thereto. In the case of the first two, contact with the atmosphere during impregnation is acceptable. Once the liquid has been depressurized, it is exposed to the atmosphere (ζ approx. 30 ~
Even if you leave it for 60 minutes, the effect will not be lost. The pressure reduction conditions are determined by the vapor pressure of the solvent and monomer in the resin liquid.
~100 rmH9 is good. Although the treatment time varies depending on the treatment method, a few minutes is sufficient for the method of dropping the resin liquid into a vacuum container. Decompression treatment is a resin liquid that can be impregnated without the need for easily volatile solvents, does not substantially generate reaction by-products such as gas or liquid during the curing reaction process, and can be molded without pressure. It is more effective. This is because virtually no-pressure molding is possible without being limited by the reduced-pressure treatment conditions imposed by solvent recovery, but the risk of bubble generation under these molding conditions can be safely avoided, and pressure is not applied during curing. do not need. In particular, an unsaturated polyester resin that is liquid at room temperature is one of the most preferred embodiments of the present invention, and has a viscosity of 0.
．． Any commercially available one having a value of about 1 to 15 poise can be used. Styrene is generally used as a crosslinking monomer for unsaturated polyester resins, but the vapor pressure of styrene at room temperature is about 6 HP, and styrene is also used in the present invention. is preferable. The proportion of styrene in the resin liquid is generally about 30 to 50% by weight. In this case, a method of injecting into a container with a pressure of about 2 to 30 mF (F) is sufficient to achieve the purpose. The reduced-pressure treated resin liquid is continuously supplied to a large number of sheet-like substrates that are being sent together. One end of the pipe is opened at the bottom of the resin liquid storage section (8), and the other end is connected to the upper part of the pressure reducing apparatus (9). The nozzle 5ζ is connected, and due to the negative pressure of the pressure reducing device (9),
The resin liquid is extracted from the reservoir (8) and jetted through the pipe into the pressure reducing device (9). The amount of ejection may be controlled by providing a cock f16) in the nozzle of the pressure reducing device (9) or using a liquid supply pump (not shown). The pressure reducing device (9) is equipped with a deaeration port on the side and a leak valve 0.
7), the oil rotary vacuum pump 419 is connected via the cold trap (181), and the inside of the pressure reducing device (9) is under negative pressure, preferably less than 30 ml of HF (7 g).The degree of vacuum is measured using a manometer. The lower part of the pressure reducing device (9) is connected to the impregnating device (2) via a resin liquid supply pump C1J. The resin liquid spouted inside falls into the cylindrical sealed container of the pressure reducing device.The falling distance in the pressure reducing device (9) is set at 50 to 100C.
1! Normally, the depressurization process will be completed if the temperature is reduced to 1. If the fallen resin liquid is always strained so that one can remains at the bottom of the container, the reduced pressure treated resin liquid can be stably supplied. When it is necessary to adjust the back pressure according to the capacity of the resin liquid supply pump, place a cylindrical sealed container above the supply pump, or place the depressurized liquid in a cushion tank (Fig. (not shown) may be stored. Next, the resin liquid is supplied to the impregnation device (2) by the supply pump 20, but when an impregnation bath is used, it is not preferable to use an apparatus in which the resin liquid remains in the bath for a long time. Base material +
A method of supplying from one side, such as a curtain flow one-sided system, which can directly supply the resin liquid C, is preferable. The overflowing resin liquid is collected in the resin liquid storage section (8) and subjected to the depressurization treatment again. A large number of base materials impregnated with resin liquid are continuously fed for one second, and then, for example, a laminating device (
3), and at the same time, a covering film or metal foil to be bonded is laminated on both sides, and then transported to a thermosetting furnace (4) under no pressure. After curing, it is cut into a predetermined length to obtain a laminate (7) or a metal foil clad laminate. Decompression treatment can be applied to any material used in conventional methods, such as paper whose main component is cellulose fiber, glass cloth, glass fiber non-woven fabric, asbestos cloth or synthetic woven fabric, and synthetic fiber non-woven fabric. Cloth is particularly effective. This method is surprising in that it can ensure excellent productivity, and although the present inventor has not fully elucidated the reason for this fact, Cζ is dissolved in the resin liquid by the reduced pressure treatment. As a result of the reduced amount of dissolved air, after treatment,
The amount of air that can be dissolved in the resin liquid increases, and therefore (the air trapped in the substrate during impregnation can be dissolved into the impregnating resin liquid at a sufficient rate, and the air bubbles inside disappear before the end of curing). It is assumed that the reduced pressure treatment has the effect of removing air bubbles that are trapped when mixing catalysts, modifiers, etc. into the resin liquid, but this is not the main focus of the present invention. It is well known that a resin solution that can be allowed to stand still is treated under reduced pressure for the purpose of defoaming in a viscous resin solution.The conventional vacuum treatment for defoaming can be carried out in the present invention. It is considered that this is not the same as vacuum treatment.The reason is that even if paper is impregnated with a 4 poise unsaturated polyester resin liquid that has been left to stand still and sufficiently degassed, the impregnation speed is lower than that before it was left to stand still. However, if the resin liquid is subjected to the reduced pressure treatment described in the present invention, and then intentionally stirred and impregnated with a material containing air bubbles, the time it takes for the air bubbles inside the impregnated paper to disappear will be significantly reduced. In any case, according to the present invention, the time required for air bubbles to disappear in impregnated paper is generally reduced to 7.
2 to 5 minutes. A similar effect can be obtained when a glass cloth base material is impregnated with an epoxy resin liquid. In the vacuum treatment method of the present invention, it is preferable to increase the surface area of the resin solution to be treated, such as by ejecting it from a vacuum container, rather than exposing the resin solution that can be allowed to stand still to the vacuum hinge ζ as described above. According to this method, the effects of the present invention will not be lost even if the treatment liquid contains air bubbles and the air bubbles are further drawn in during supply. The reduced pressure treatment according to the method of the present invention has the effect of reducing dissolved oxygen, thereby eliminating the influence of oxygen on the radical reaction during curing of the unsaturated polyester resin. In the case of unsaturated polyester substitute resins that are liquid at room temperature, common commercially available products contain about 0.03 to 0.1% of water. This was reduced to 0.04 el by the depressurization treatment of the present invention.
It is preferable for the content to be less than I, preferably less than 0.02%, in terms of production and product performance, since it eliminates bubbles that form under the moisture and does not inhibit the Ic curing reaction. In the lamination step fζ, the plurality of resin liquid-impregnated base materials are converged and laminated using a roll and a blade-like object, or two rolls. At this time, remove the excess resin impregnated or attached to each impregnated base material.
The spacing between the rolls and the blades or rolls is adjusted according to the desired product thickness. Simultaneously with the lamination or afterward, the coating is laminated using a separately installed laminator, and it is preferable that the width dimension of this coating protrude beyond both ends of the laminated resin solution-impregnated base material. . When such a coating is used, even if excess resin liquid is squeezed out from the ends of the resin liquid-impregnated base material laminate during lamination, it is possible to retain the resin liquid, which is preferable. In the present invention, after laminating sheet-like base materials and laminating film-like or sheet-like coatings (hereinafter sometimes abbreviated as "coatings") on the upper and lower surfaces, continuous curing is performed in the curing process. Since the application of pressure is essentially troublesome and unnecessary, a wide variety of coatings can be selected depending on the purpose. For example, when the resin to be impregnated is unsaturated polyester resin or epoxy resin, various types of release paper or cellophane with a thickness of about 10 to 200 μm, various synthetic resin films such as Teflon and polyester, or aluminum, steel, stainless steel, iron, Various metal foils such as phosphor bronze can be used. As shown in the embodiment of FIG. 4, the coating O3 can be peeled off from the laminate after the resin liquid has hardened, and the coating can be reused by winding it up on a recovery roll 1ζ, which is desirable from a cost perspective. For this purpose, it is preferable that the coating is easily peeled off from the cured laminate, and the thermosetting resin and the coating are appropriately combined, and a release agent is used if necessary. In the present invention, the coating is formed into an endless belt.
If it is used after straining, the coating can be continuously peeled off and reused, which is preferable. In this case, a sheet-like material with a thickness of about 1+s can be used, and stainless steel, phosphor bronze, and Teflon are preferable materials. The release agent is applied in advance to the entire surface or both edges 6 of the surface of the coating that is in contact with the surface of the laminate before laminating the coating. If a release agent is applied to the entire surface of the proboscis 82, the release agent may migrate to the product laminate, which may impair the printing performance of various pastes or resists on the product, which may be undesirable. In such a case, it is preferable to apply the mold release agent to both edges of the laminate. This is because after the laminate passes through the thermosetting furnace (4), the coating is peeled off and both parts of the product are removed, so the areas to which the release agent has been applied will not become a product. , the aforementioned unfavorable effects can be eliminated. As the mold release agent, a silicone mold release agent is suitable, and for example, Daifree MS743 (trade name, manufactured by Daikin Industries, Ltd.) gives good results. Among product characteristics, smoothness is important for printing resistance pastes and resists on products, and transparency is important because it allows the shape of these printed patterns and the circuit pattern of the printed circuit board, as described below, to be confirmed from the back side. It's meaningful because it's easy. In the present invention, the required number of base materials impregnated with resin liquid are laminated, but at this time, rolls or blades are used to remove excess resin liquid or air bubbles that are mixed in during lamination. However, it is desirable to control the amount of resin required. At the same time as the sheet-like base materials are laminated (Fig. '41), or laminated by a laminating machine M'23C (Fig. 4) consisting of a pair of rolls installed on the downstream side of the laminating device, the sheets are laminated at the same time. Compressive force acts on the laminate of the base material impregnated with resin liquid (generally, the surface of the base material is not smooth macroscopically or microscopically at this point, so if a coating with low rigidity is used, this microscopic Because the coating follows the surface and macroscopic irregularities, and in the present invention, it is cured under no-pressure conditions, the surface properties of the product may not be sufficient.According to research by the present inventors. , E, and d3 are 1i1・CI (where E is the modulus of elasticity?/cd, and d is the thickness c-), and the rigidity value of the film or sheet material is 3X10.
When it was 1 or more, practically preferable surface smoothness was obtained. Furthermore, more desirable results are obtained when the stiffness value is 5×10 Kg·4 or more. The present invention is achieved by covering both sides with such a coating and curing the resin liquid. In the present invention, the base material has a thickness of 200 to 300 mm.
Linter paper or kraft paper having a μ and a basis weight of around 150 n/rIe is suitable. These papers usually have microscopic irregularities as shown in Figure 2, but the stiffness value is 3X10-''?
a coating of less than 1, for example a polyester film with a thickness of 35μ (having a flexural modulus of 28,100 Kg/ci;
Therefore, the stiffness value was 1.54XIO'), as shown in FIG. 2, the film would follow the unevenness of the paper, resulting in a product with poor surface smoothness. When the rigidity value of the coating exceeds 3KgxlO-3Kti·I, the ability to follow the irregularities of the base material is reduced. For example, the stiffness value is 2.
When a polyester film of 81×10 −2 9×1 and 100p in thickness is used, as shown in FIG. 3, the following of the unevenness f of the base material is slight. More preferably, a coating with a stiffness value of 5×10 −·1 or more, for example, an aluminum foil with a thickness of 100 μ (flexural modulus of elasticity of 0.67×1t)′KP·((therefore, a stiffness value of 6.7×10′)・cm) or thickness is 10
0P stainless steel foil (flexural modulus is 186001CP/
, ffl, and therefore the stiffness value is 1.86 to 7·α), etc. are suitable in the present invention. The coating may be a single film or sheet, and
It may also be a composite film or sheet. In general, the stiffness decreases as the temperature increases, but in the present invention, since covering the product Ct body with the coating is usually possible at room temperature, the stiffness value at room temperature is applied, but in particular Plastic films whose stiffness value significantly decreases at the curing temperature are not preferred. Also, those that have high adhesiveness to cured unsaturated polyester resins, epoxy resins, etc. are not preferred. From this point of view, cellophane, polyester, polypropylene, Teflon, polyamideimide film, etc. are suitable. Also, aluminum foil, rolled copper foil, and stainless steel foil are suitable. As described above, in the present invention, the coating can be easily peeled off without using a special release agent or release paper between the coating and the laminate, and there is no need to insert release paper. be. If a film-like material is inserted for the purpose of mold release, it is preferably a composite sheet-like material bonded to a coating. The coating is desirably long so that it can be continuously fed out from a roll and recovered while being rolled up after peeling. Furthermore, if the coating is formed into an endless belt, it can be used continuously and repeatedly. For such use, the stiffness value of the coating should be 3X10'
It is preferable to have KS′·1 or more and flexibility. If the rigidity is too high, the flexibility will decrease, so 3X10-
The range of 39.1 to 3X10"K61.α is suitable. Also, as can be easily inferred from Fig. 3, the surface geometry of the product depends on the surface roughness and geometric surface texture of the coating. The surface condition of the product is one of the most important characteristics, especially for laminates for electrical applications. For example, when manufacturing film-type composition carbon resistors by applying resistance paste to an insulating substrate. , if the surface roughness of the insulating plate is large,
Unusual protrusions or pinholes may occur on the coated resistor.
These protrusions and pinholes may cause noise during use.
It also reduces the service life. The preferred surface smoothness is R
max (maximum height of surface roughness) is approximately 5 microns or less,
More preferably, it is about 4 microns or less. On the other hand, if Rmax becomes significantly small, the adhesive force between the resistor paste and the surface of the insulating substrate decreases, and the applied resistor may peel off. The adhesiveness between the resistance paste and the insulating substrate is determined by chemical factors, ie, the compatibility or polarity of the resistance paste and the insulating substrate, and physical factors, ie, the surface roughness of the insulating substrate. When it is about 0.4 micron or more, the adhesiveness between the coated resistor and the substrate and the transferability of the paste are good. Surface smoothness was based on JIS-BO601. The measurement was carried out using a stylus type surface roughness measuring machine under the conditions of a stylus tip radius of 2.5 microns and a measuring force of 0.12. In order to obtain the one-layer body as described above in the present invention,
This can be achieved by using a film or sheet coating having a surface roughness of 0.4 microns or more and about 5 microns or less. Although the case where the base material is paper has been described above, the same applies to the case where other base materials are used. For example, in the case of glass cloth, there may be unevenness due to the texture, but this is not a problem (it is obvious that the present invention can be applied to it. The coated material is laminated on one side of the laminated base of the impregnated base material and peeled off after the resin liquid hardens.However, on the other side of the Q waste material, there is a laminated layer that is a type of coating but is not intended to be peeled off. An electrical laminate with excellent surface smoothness can be produced by laminating metal foils or by laminating metal foils for bonding on both sides of the laminate. Electrolytic t!A foils intended for use in printed circuit boards are widely available on the market, and it is preferable to use them from the viewpoints of corrosion resistance, etching properties, adhesion properties, etc. We will discuss single-sided metal foil laminates and double-sided metal foil laminates in which electrolytic copper foil, electrolytic iron foil, aluminum foil, etc. are laminated on one or both sides for use as substrates.For example, commercially available 1 oz/ft. When using electrolytic copper foil in step 2, if the base material is special paper, the smoothness of the surface of the copper foil may be slightly inferior to that of conventional press-formed products. According to the inventor's study, this does not have any adverse effect on screen printability, etching, or other properties.For example, in the present invention, when using an unsaturated polyester resin, the method described above Even if electrolytic copper foil, etc. is directly bonded, practical products can be manufactured if carefully carried out. - Layer To obtain a high-performance product, it is necessary to When continuously laminating metal foil on a laminate, a more preferable metal foil-clad laminate can be obtained by continuously supplying an adhesive between the metal foil and the laminate.Previously applied pressure For example, in the production of paper-based phenolic resin copper-clad boards, an electrolytic copper foil with an adhesive is used, which is a phenol-modified butyl rubber adhesive baked into the B state. In the manufacturing method, rather than using a commercially available metal foil with adhesive, the method is similar to the apparatus shown in FIG.
In this configuration in which metal foil (I) is laminated, an appropriate adhesive stored in an adhesive tank (10,000 yen) is continuously supplied by an adhesive supplying device between the laminated base material and the metal foil. was found to be preferable in terms of productivity and quality.More preferably, it is applied to the metal foil immediately before lamination and then subjected to an appropriate heat treatment for film formation.Adhesion between the metal foil and the resin-impregnated base material In order to effectively achieve this, the adhesive must be a liquid or semi-liquid, i.e. viscous, that does not contain components that need to be removed, such as solvents, and does not generate unnecessary reaction by-products during the curing process. From this point of view, for example, unsaturated polyester adhesives, epoxy resin adhesives, polyisocyanate adhesives, or these modified adhesives are suitable. By introducing such a suitable adhesive, it is possible to continuously produce a metal foil-clad laminate that has excellent adhesion strength of metal foil, as well as excellent solder heat resistance and electrical insulation properties. The supply method may be to coat the metal foil immediately before laminating the metal foil, or to coat the surface of the laminate and laminate the metal foil, or to inject it into the joint surface during lamination. However, in the above method, depending on the method of supplying the adhesive, air bubbles may be introduced into the adhesive, and certain combinations of resin liquid and adhesive may cause abnormal curing or separation of the mixture. Therefore, the present invention also proposes a further improved method.Immediately before laminating the metal foil (IO) drawn out from the metal foil supply device +111, As shown in Figure 6, an adhesive coating device (to) and an adhesive heat treatment device (4) are arranged, and the process of continuously applying adhesive to metal foil and heat-treating the coating film is added.Adhesive coating As for the equipment, a normal roll coater, flake coater, wire bar coater, comma coater, etc. can be used.The first purpose of heat treating the coating film is to dry the solvent when using a solution-based adhesive. Therefore, in the present invention fζ, it is not necessary to be non-adhesive after drying the solvent as in the conventional method. - The purpose of Kimi 2 is to precure a thermosetting adhesive, and to The degree of curing should be controlled to an appropriate degree. At this time, it is preferable not to proceed with curing too much (generally, it is best to control the degree of curing to a degree that maintains some tackiness. Third
The purpose of this is especially when using a two-component heating type epoxy resin adhesive, which has a relatively high viscosity and therefore may introduce air bubbles during mixing, causing the coating film to contain air bubbles. can be removed by such a hot saw EJ+. Hereinafter, a paper-based copper-clad laminate using 1 non-foamed polyester 1 degreaser and an epoxy adhesive will be explained as an example.
As the adhesive, a mixture of bisphenol A type epoxy resin, polyamide resin, and fingers is suitable. The paper unwound from the paper unwinding reel comes into contact with a resin liquid in an impregnating bath and becomes resin-impregnated paper. For example, seven sheets of resin-impregnated paper are stacked using a laminating device (3) consisting of a pair of rolls. This assembled product is then laminated with electrolytic copper foil. The foil fζ is the front. Adhesive is applied as shown. When using epoxy adhesive, heat treatment is 100 to 15
It is best to do this at a temperature of 0°C for about 2 to 7 minutes. During lamination, it may be cooled to room temperature. At this time, it is best to perform heat treatment to the extent that some stickiness remains when touched with the finger. If it is completely dry to the touch, the adhesion with the polyester resin-impregnated paper will be impaired, and if it is too dry, the resin liquid and adhesive will be mixed together in the subsequent curing process.
In some cases, the performance of the adhesive may be reduced. The thickness of the adhesive coating may be about 10 to 100 μm, and preferably about 20 to 40 μm. Then, it is transported to a curing furnace (4). At this time, if necessary, a cover film such as cellophane or polyester film is laminated on the opposite side of the surface to which the metal foil is bonded. It is also possible to use metal foil instead of the cover film to produce a double-sided metal foil laminate. The curing conditions must be selected depending on the catalyst, conveyance speed, etc., and, for example, 100° C. for 1 hour is preferable. The above method (thereby, the peel strength of steel melt is 1.6
Copper-clad laminated IJ bodies of xp to XXXPC in the NEMA standard, which is ~2.0 Kl/C10, can be manufactured with excellent productivity. As described above, the present invention has made possible the continuous production of metal foil-clad laminates, which has not yet been put into practical use industrially. The thermosetting resin liquid to be impregnated into the base material is preferably liquid at room temperature, but is not limited thereto, and even if it is solid at room temperature, it can be turned into liquid by adding t to meet the purpose f of the present invention. Of course, this can be used. Next, an example will be described in which the adhesive effect of the present invention is further improved. When using an unsaturated polyester resin and an epoxy resin as an adhesive, it is preferable to use an amine-curing epoxy resin from the viewpoint of matching the curing speed of both. Peroxides used as peroxydicarbonates,
Ketone peroxides, hydroperoxides,
Or rather than using diacyl peroxides etc.
Use of one or more peroxides selected from peroxyketals, dialkyl peroxides, and peroxyesters provides particularly favorable results in terms of solder thermal properties, electrical insulation properties, and adhesive properties. A good blending amount is about 0.5 to 2.0 parts based on the resin liquid. Although the inventor has not fully elucidated the reason for this,
In general, solder heat resistance, electrical insulation properties, and adhesive properties depend on the properties of the cured adhesive, but during the process where the resin-impregnated base material and adhesive come into contact and curing is completed, peroxide diffuses into the adhesive layer. Alternatively, it can be assumed that mixing of the resin liquid and adhesive occurs, and when peroxydicarbonates, ketone peroxides, hydroperoxides, or diacyl peroxides are used, these substances may cause abnormalities in the epoxy resin. It is thought that this may cause curing and the resulting cured product may not have sufficient properties. Therefore, preferred catalysts include peroxyketals such as 1-1-bis(t-butylperoxy)3
．． 3.5-)limethylcyclohexane, 1-1-bis(
C-butylperoxy)cyclohexane, n-butyl-
4,4-bis(1-butylperoxy)valerate, dialkyl peroxides such as di[-butylperoxide, 2,5-dimethyl-2,5-di(butylperoxy)hexine-3, Examples of peroxy esters include [-butyl peroxy acetate,
[-Butylperoxy 2-ethylhexanoate, [-
butyl peroxylaurate, [-butyl peroxybenzoate, etc. As unsaturated polyester,
It may be a known compound synthesized from an unsaturated dibasic acid, a saturated dibasic acid and a glycol, or it may be a bisphenol A type polyester resin or a vinyl ester type resin.Styrene is commonly used as a crosslinking monomer. As the epoxy resin, bisphenol A type is preferred, and as the amine curing agent, well-known ones such as aliphatic amines and aromatic amines can be used. Any of these can be used. Furthermore, polyamide resins, terminal amino-terminated polybutadiene nitrile rubber, etc. may also be used as this type of curing agent. Alternatively, a mixture of the above curing agents may be used. By this,
Although it is possible to efficiently produce a metal foil-clad laminate with excellent performance, it is also possible to combine an unsaturated double bond such as a vinyl group with an epoxy group, especially in the area where the resin-impregnated base material and the adhesive come into contact. By interposing a compound containing a compound such as glycidyl methacrylate, glycidyl allyl ether, partially epoxidized soybean oil, etc., the affinity between the unsaturated polyester resin layer and the epoxy resin layer is further improved. This is effective in suppressing the occurrence of defective products due to peeling at the interface. In addition, when impregnating the base material with epoxy resin, especially when the base material is a commercially available glass cloth surface-treated for epoxy resin, and when using commercially available 4-foil for printed circuit electrolysis,
Since epoxy resin has good adhesion to copper foil, it is possible to obtain a product with excellent adhesion strength to copper foil without introducing an adhesive as described above. When the substrate is impregnated with unsaturated polyester resin or epoxy resin, better results can be obtained by applying a surface treatment agent, particularly a silane coupling agent, to the surface of the copper foil. This surface treatment agent is applied prior to applying an adhesive to the surface of the metal foil. As the silane coupling agent, any silane coupling agent that is generally used for the interface between inorganic and organic materials can be used, but Union Carbide Charge-1100 and A-187 were suitable. It is preferable to thinly (continuously) apply a 0.1-1% alcohol solution or aqueous solution of a silane coupling agent to the metal foil, and then dry it continuously. Regardless of whether a metal foil is used or not, it is best to pass the metal foil through a hot air oven and dry it with hot air at 100°C for several minutes. Dry for a few minutes to 20 minutes.Drying removes adhering moisture and improves adhesion with adhesives and resins.In order to minimize warping, twisting, and other deformation of the product, the following invention was introduced. Curable resin generally shrinks in volume as it cures, causing residual strain inside the resin and warping or twisting of the product.Also, if the resin is not completely cured, the product may If the resin is placed in a heated environment, new warping or twisting will occur.Furthermore, incomplete curing will significantly reduce heat resistance, chemical resistance, and mechanical properties.Also, the curing of the resin will If the product is not completely cured, if the product is subsequently placed in a heated environment, not only will new warpage and twisting occur, but incomplete curing will result in poor heat resistance, chemical resistance, and mechanical properties. According to the research of the present inventor, in order to complete curing when manufacturing laminates continuously, it is necessary to use the extremely largest curing equipment,
Alternatively, there are problems that require extremely slow line speeds. In the present invention, the laminate is cut at a stage where the curing has progressed to a certain extent, and then the laminates are cut to a standard size, stacked in multiple layers, and placed in a heating chamber to proceed with curing. It is possible to proceed with the curing of the whole at the same time. Therefore, it is sufficient to cure the laminate in the continuous manufacturing process to the point where it can be cut with a guillotine cutter and the laminated coating is not obstructive (it can be peeled off).As a result, it is economical and practical. For example, when unsaturated polyester resin is used, it is possible to cut it even though it normally takes 10 hours at 100℃ to fully cure it. About 15 minutes is sufficient for this to occur. Residual strain due to curing shrinkage of the resin layer can be removed relatively easily by releasing it as warp in the width direction, but residual strain in the longitudinal direction can be removed by releasing it as a warp. Because of this, it cannot normally be removed, resulting in anisotropy in the residual strain in the vertical and horizontal directions of the product.This can cause increased warpage and twisting when the product is subsequently placed in a heated environment. In the present invention, since curing is further progressed after cutting, warpage and residual strain can be made isotropic to a practically acceptable degree during the curing process.The size of warp in the metal foil laminate depends on the resin used. Generally, epoxy resins are small (unsaturated polyester resins and diallyl phthalate resins are large).Also, even if they are the same type of resin, the composition varies depending on the composition.For example, unsaturated polyester resin and paper A laminate with a thickness of 1.6 tone and covered with a 35 μm thick copper foil has a range of 0.5 to 30% of the 9m specified by JISC-6481. However, after cutting the above-mentioned continuous body, Curing is preferably carried out at a temperature higher than the temperature of a continuous heat curing furnace, or at a temperature equivalent to the environment to which the product is exposed in practice, and then the warp can be made substantially flat by mechanically correcting the warpage. It was found that this product significantly reduces the warpage that occurs in the product in practical use, for example in a heated environment.The device shown in Figure 5 is used as a cutting device (5) in the continuous production of laminates. A second curing device (to) is installed on the downstream side of the curing device.
The laminate (7) is placed on a conveying device (toward) passing through the ID and cured for a short period of time at 150°C for 15 minutes, and then transported to the exit of the curing device 4 with two warp correction devices 13υ (2) and a turn. This is where a table ■ is placed. Long laminate single layer body (7
) is cut into practical dimensions, enters the second curing device ■,
For example, 1.
Processed at 50°C for 15 minutes, and two warp correction devices @c+n
pass. The laminate (7) passes in two directions, vertically and horizontally, between three adjacent rollers provided in the warpage correction device, and warpage is mechanically corrected. In order to obtain high productivity, the coating is not only applied to the upper and lower surfaces of the laminated base material impregnated with resin liquid, but also 1.1 to several layers are sandwiched in the middle, and after curing, the intermediate coating is layered at the border. By separating the layers into upper and lower layers, a large number of laminates could be manufactured at the same time. Since the drying time, impregnating time, and curing time described above in the present invention hardly change, productivity has been dramatically improved. It has been found that the coating acts as a separator when the substrate is layered in multiple stages. Therefore, the base material can be laminated on both sides of the coating, and the lamination of the coating and the base material can be repeated in multiple stages. If the coating is a metal foil, it can be peeled off after molding;
Further, by adhering the metal foil to either one of the laminates on both sides, a single-sided metal foil-covered laminate and a double-sided metal-foil-covered laminate are simultaneously obtained. In this case, if necessary, apply adhesive to one side of the metal foil in advance. As an example of implementation, when producing a 35P thick copper foil laminate with a thickness of 1.61111 by laminating paper substrates impregnated with unsaturated polyester resin, paper impregnated with unsaturated polyester resin For example, place 8I layer of pre-dried cellophane in the middle of the base material, laminate base materials of a predetermined thickness on top and bottom, cover with copper foil, and laminate to create two single-sided copper sheets at the same time. We were able to manufacture foil-covered laminates, achieving twice the productivity compared to conventional continuous manufacturing methods. According to the present invention, products of various types having different thicknesses can be laminated and manufactured simultaneously with the coating as a boundary, which is advantageous in preventing a decrease in productivity due to switching of products. As described above, the present invention dramatically improves the productivity of laminates in a continuous manufacturing method, but compared to manufacturing by IPi stacking, the laminate Since the overall thickness of the material is thick, the conditions such as heating efficiency during curing, heat transfer of curing reaction heat, and heat radiation change, so consideration is required. A heating furnace that can control heating, heat generation, heat transfer, and heat radiation in detail depending on the number of stages, such as a furnace with an internal furnace (divided into a few blocks and capable of appropriate temperature control), is also used. When using a catalyst or curing agent, in consideration of the heat generated during the curing reaction, a small amount of the catalyst, etc. is added to the base material located in the center compared to the impregnated resin liquid in the impregnated base material located on the outside. It is desirable to impregnate the resin liquid in a reduced amount.If the thickness is difficult to cut with a guillotine cutter, it is preferable to install a movable slicer to cut it. The characteristics of the products manufactured in each example are summarized in Table 7. Example 1 An unsaturated polyester resin was manufactured using the manufacturing equipment shown in Figure 4. As a liquid, 37% by weight of styrene as a polymerization monomer is added to an unsaturated polyester synthesized by a conventional method using maleic acid, isophthalic acid, and ethylene glycol as raw materials in a molar ratio of 82:18:100. To obtain 100 parts by weight of this product, 1 part by weight of cumene hydroperoxide was added as a curing catalyst and 6 parts by weight as a curing aid.
% cobalt naphthenate solution was added to obtain an unsaturated polyester resin liquid composition. The properties of this cured resin liquid composition were as shown in Table 2. Table 2 Commercially available kraft paper mainly composed of cellulose fibers shown in Table 3 was used as the sheet-like base material. Table 3 Table 4 The polyester film was peeled off using a coating stripping device 12IJ consisting of a pair of rolls, and wound up using a coating winding device. The spacing between the laminating rollers was adjusted so that the weight ratio of the resin liquid to the two impregnated paper substrates was about 55% immediately after laminating the polyester films. In this way, finally, a laminate having a thickness of 0.501 mm and an external dimension of 1020!1lIIIX1020 was continuously manufactured. The laminate was subjected to an alkali resistance test by immersing it in a 5% caustic soda aqueous solution at 40° C. for 30 minutes and a solvent resistance test by immersing it in boiling toluene for 2 minutes, but no abnormalities were found in all the examples. Example 2 In Example 1, a hot air drying device was operated as the substrate drying device (2), and the paper base material was continuously passed through the hot air drying device at 100° C. for 10 minutes. Other conditions are the same as in Example 1. Example 3 In Example 2, the number of paper base materials to be continuously conveyed was set to 5.
A laminate having a thickness of 1.5 mm was produced. The spacing between the laminating rollers was adjusted, and the weight ratio of the (M fat liquid) to the five sheets of impregnated paper base material was approximately 60%. Made of polymer).Na2
The glass transition temperature of the cured product was 120°C. Example 5 In Example 3, the unsaturated polyester was changed to the following. That is, maleic acid, isophthalic acid, and diethylene glycol are used as raw materials, and the molar ratio of each is 32:6.
Styrene was mixed to an unsaturated polyester resin synthesized by a conventional method at a ratio of 8:100 to a ratio of 37 weight percent. This resin liquid has a viscosity of 4.5 poise at 25°C and is a liquid unsaturated polyester resin at room temperature. Note that the glass transition temperature of the cured product obtained from this resin liquid was about 55°C. Example 6. 7. 8゜The dip impregnation method adopted in Examples 3.4 and 5 was changed, and the resin liquid was allowed to flow down from above the paper base.
A single-sided impregnation method using a so-called curtain flow method was used. As a result, there were almost no microscopic bubbles in the product compared to Examples 1 to 5, and a product with better ring heat resistance was obtained. In addition, the test results of the products are as shown in Example 3.
The results were similar to those of 4 and 5. Examples 9.10 and 11 In Examples 6.7 and 8, the resin liquids were previously treated under reduced pressure and the impregnation time was shortened to 4 minutes. As shown in Fig. 1, an example of depressurization treatment is shown in Fig. 1.
The resin liquid was injected into the inside of a sealable cylindrical container with a height of 100C11 at a rate of 10j/min, and the pressure inside the container was adjusted to be always 20 mHg. The resin liquid treated under reduced pressure was drawn out from the lower part of the cylindrical container using a pump and was supplied above the paper base material. There were almost no air bubbles in the product, and the product properties were the same as those of Examples 3.4 and 5, even though the impregnation time was greatly shortened.
The results were the same as those of . Examples 12.13 and 14 In Examples 3.4 and 5, cumene hydroperoxide used as a curing catalyst was converted to t-butyl peroxy-2-ethylhexanoate, which is an aliphatic peroxy ester. changed. In this product, the odor generated under heating conditions of 180° C. for 30 minutes was significantly reduced. In addition, in order to cut the obtained 1a body after curing and further harden it,
Heat treatment was performed in a hot air oven at ℃ for 10 hours. This laminate had stable qualities such as solder heat resistance, dimensional stability, and insulation properties. Example 15 The unsaturated polyester resin composition used in Example 14 (with respect to 100 parts by weight of the unsaturated polyester resin synthesized in Example 5, t-butylperoxy-
Using 1 part by weight of 2-ethylhexanoate and 0.2 parts by weight of cobalt naphthenate (6), the vacuum treatment and impregnation method shown in Examples 9, 10 and 11 were performed. The conveyance speed of the substrate was tripled so that the impregnation time was 5 minutes and the curing temperature was 100'C1, and the curing time was 22.5 minutes. Other manufacturing conditions were the same as in Example 1. After a curing time of 22.5 minutes, it was cut to obtain a laminate.
With this curing time, curing was insufficient and the quality was not sufficient. Therefore, after cutting, we added a process of heat treatment in a hot air oven at 100 degrees, 10 hours, and 160 degrees CIO to further promote sufficient hardening. products were obtained. By simply providing a hot air stove separately and adding a heat treatment process after cutting, the production efficiency of the apparatus of Example 1 was improved by four times. Example 16 The paper base material of Example 1 was subjected to the following pre-impregnation treatment. A long piece of paper was immersed in an 8% methanol solution of N-methylolacrylamide for 5 minutes, taken out, air-dried for about 30 minutes, and then heated and dried at 100°C for 20 minutes. An N-methylol acrylamide treated paper was obtained. At this time, the amount of N-methylol acrylamide attached to the paper was 1162%. Prepare 5 rolls of the long treated paper mentioned above,
A laminate with a thickness of 1.5M was obtained in the same manner as in Example 15 while continuously conveying these individually. Compared to Example 15, the properties are markedly improved in solder heat resistance and electrical properties during moisture absorption treatment. Example 17 In Example 16, the coating film followed the unevenness of the paper base material, and gentle undulations were observed on the surface. In Example 16, this coating was coated with a long piece of stainless steel foil (material: 5US) with a thickness of 100 μm1 and a so-called BA surface finish.
304) + Manufactured with modifications. Further, the surface roughness of this stainless steel foil was Rmax = 2.5 microns, and the rigidity value = 1.861'f.ox. The above-mentioned undulations disappeared, the surface smoothness of the product was evaluated as excellent, and the surface appearance, printability of various resists and pastes,
The transfer properties of these inks were satisfactory. Example 18 The paper substrate described in Example 1 was subjected to the following pre-impregnation treatment. That is, in 50 parts by weight of methanol in which 1.5 parts by weight of oleic acid monoglyceride (Riken Vitamin Oil Suchemal 0L-100) was dissolved, 6 parts by weight of methylolmelamine (Nippon Carbide Kogyo Nikaresin S-305) was dissolved in 50 parts by weight of water. A turbid treatment liquid was prepared by pouring the mixture with strong stirring. The above-mentioned long paper was continuously immersed in this treatment liquid, and after being taken out, the long treated paper base material was heated and dried at 120° C. for 20 minutes and wound into a roll. In Example 17, the long treated paper was changed to the one described above, and the thickness was 1
．． A 5-shoulder laminate was obtained. Product characteristics are shown in Table 7. This table was approximately the same as the characteristics of the product of Example 17. Example 19 In Example 18, a laminate was manufactured by laminating stainless steel foil on both sides of a base material impregnated with a resin liquid and soldering this after curing. /
ft2 electrolytic A foil (manufactured by Koushu Metal Foil Powder Industry Co., Ltd., T-7), this electrolytic copper foil was not peeled off after curing, and only the stainless steel foil on the opposite side was peeled off to obtain a copper foil-clad laminate. Ta. Other conditions are the same as in Example 18. Example 20 The product of Example 19 has a drawback of a large amount of warping. Therefore, as shown in the device shown in Fig. i5, a warping process was added, and the gap between the three rolls was adjusted and corrected, thereby greatly improving the warped bond. Example 21 In order to improve the adhesion strength and solder heat resistance test results of the copper foil of the product obtained in Example 19, before laminating a long electrolytic copper foil in Practical Example 19, the process shown in Fig. 6 was carried out. An adhesive coating step was added to the device. The adhesive has the formulation shown in Table 5. Coating thickness on copper foil is 60
It was set as μm. The peel strength of the electrolytic copper foils of the products in Table 5 satisfactorily met the JIS standards. Example 22 In Practical Example 21, immediately after coating the electrolytic copper foil with the coolant using the apparatus shown in FIG. 6, the 'ra\II copper foil was passed through a heat treatment apparatus and a heat treatment process was added at 100°C for 5 minutes. A single-sided copper foil plate was manufactured. The properties of solder heat resistance and peel strength of electrolytic copper foil are the same as those described above in Example 23. .5
-The characteristics of the product in which beef san has been changed to trimethyl Schiff a are as follows:
The solder heat resistance during temperature absorption (conditions were C-96155/95) was improved to 10 to 27 seconds, and other characteristics were the same as those of Example 22. Example 24 An experiment was conducted in which no curing aid was added to real blood example 23. The characteristics of the product were similar to those of Example 23. Example 25 In Example 23, a silane coupling agent (Ucc Crack A-18) was added before coating the adhesive onto the electrolytic copper foil.
7) Apply an aqueous solution containing 0.5% by weight to the surface of the electrolytic copper foil for about 10 minutes.
Continuous coating process to a thickness of μm, then 100°
A single-sided copper-clad board was manufactured by adding a step of drying under conditions of 0.2 minutes. In particular, solder heat resistance and electrolytic copper foil peel strength were improved. Example 26 Commercially available long glass cloth (Nittobo Co., Ltd. WE18-Z I
While continuously conveying 8 sheets of s), first, at 100℃,
Continuously dried under conditions of 10 minutes, then Example 9.1
Liquid f at room temperature treated under reduced pressure in the same manner as 0 and 11
i6 Epoxy resin composition shown in Table (viscosity is 6 at 25°C,
5 poise) was allowed to flow down from above the glass cloth using a curtain flow system. (Left below) Table 6 Impregnation time: 10 minutes. Eight glass cloths were laminated, and a commercially available electrolytic copper foil (Digashi Metal IT-7) coated on both sides with a silane coupling agent (UCC-A-1100) was continuously laminated. The spacing between the laminating rollers was adjusted so that the weight ratio of the resin liquid to the impregnated base material was about 58%. Then, it was continuously cured at 130° C. for 60 minutes, cut, and then further heat-treated at 180° C. for 2 hours to obtain a product with external dimensions of 1020 mi×1102 O+x and thickness of 1.61 mm. An excellent laminate with good balance in all properties was obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an outline of an apparatus used to implement the present invention. FIG. 2 is a cross-sectional view of a product using a coating with low rigidity. FIG. 3 is a cross-sectional view of a product using a highly rigid coating. @Figures 4 to 6 are explanatory diagrams showing other examples of devices used to implement the present invention.

Claims (1)

[Claims] 1. A thermosetting resin liquid which is liquid at room temperature and which essentially does not require a drying process and hardly generates reaction by-products such as gas or liquid during the curing reaction process under reduced pressure. A film-like or The sheet-like coating is laminated and then continuously cured under conditions of substantially no molding pressure. Method B, in which the thermosetting resin liquid to be impregnated is excessively impregnated in advance, and the excess resin liquid is removed at the same time and/or before laminating the sheet-like coating on the laminated base material of the impregnated base material. When laminating liquid-impregnated substrates and/or laminating sheet-like coatings on both sides of the laminated substrate, a method of supplying a new thermosetting resin liquid allows the resin liquid after laminating the coating to be applied. The amount of resin liquid added to the impregnated laminated base material is adjusted to a desired specific amount within the range of 30 to 80% by weight based on the resin liquid impregnated laminated base material,
A continuous hard laminate for electrical use, characterized in that the curing of the resin liquid-impregnated laminated base material is at least to the extent that it can be peeled off from the surface of the laminated base material without any hindrance when the sheet-like coating is not adhered to the surface of the laminated base material. Production method. (2) One or both of the film-like or sheet-like coverings is metal foil, and after the impregnating resin liquid has hardened, one or both of the coverings is used as a metal foil-clad laminate without being peeled off. A method for continuously manufacturing a laminate according to claim 1. (3) The continuous manufacturing method of a laminate according to claim 2, wherein the metal foil is an electrolytic copper foil for printed circuits. (4) The method for continuously producing a laminate as defined in any one of claims 1 to 3, wherein the thermosetting resin is an unsaturated polyester resin that is liquid at room temperature. (5) The method for continuously producing a laminate as defined in any one of claims 1 to 3, wherein the thermosetting resin is an epoxy resin that is liquid at room temperature. (6) A method for continuously manufacturing a laminate as defined in any one of claims 1 to 3, wherein the sheet-like base material is cellulose-based. (7) A method for continuously manufacturing a laminate as defined in any one of claims 1 to 3, wherein the sheet-like base material is made of glass fiber. (8) Any of claims 1 to 3, wherein the sheet-like material is impregnated in advance with a pre-impregnating liquid before being impregnated with the resin liquid, and the pre-impregnated base material is dried if necessary. Continuous manufacturing method for laminates specified in (9) The sheet-like base material is cellulose-based, the thermosetting resin is an unsaturated polyester resin that is liquid at room temperature, and the pre-impregnation liquid is an N- 9. The continuous production method of a laminate according to claim 8, which contains a methylol compound. (10) The continuous production method of a laminate according to claim 9, wherein the N-methylol compound is a modified aminotriazine methylol compound. (11) N-methylol compounds have a general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (However, R_1 is H or CH_2, R_2 is H or C
The method for continuously producing a laminate according to claim 9, which is a compound represented by the following alkyl groups (_1_ to_3). (12) The sheet-like base material is cellulose-based, the thermosetting resin is an unsaturated polyester resin that is liquid at room temperature, and the pre-impregnation liquid is N containing no unsaturated bonds that can be copolymerized with the polymerization monomer. - a methylol compound, a, a functional group that can be condensed with or added to the N-methylol compound, b, and a polyfunctional compound that has an unsaturated bond that is copolymerizable with a polymerizable monomer; A method for continuously manufacturing a laminate according to Scope Item 8. (13) The sheet-like base material is cellulose-based, the thermosetting resin is an unsaturated polyester resin that is liquid at room temperature, and the pre-impregnation liquid is a mixture of A and B or a condensation product of A and B. A method for continuously producing a laminate according to claim 8, wherein A is a methylolmelamine and/or methylolguanamine, and B is a higher aliphatic derivative having at least one group capable of bonding to a methylol group in the molecule. (14) The continuous production method of a laminate according to claim 13, wherein the group capable of condensing with a methylol group is a group selected from the group consisting of a hydroxyl group, a carboxyl group, an amino group, and an amide group. (15) The higher fat derivative is one type or a mixture of two or more types selected from the group consisting of oleyl alcohol, oleic acid, oleic acid monoglyceride, oleic acid diglyceride, oleic acid amide, and oleylamine. Continuous manufacturing method for laminates. (16) The mixture or condensation product of the N-methylol compound and higher aliphatic derivative is dipped into a sheet-like substrate and the total amount of the mixture or condensation product deposited on the substrate after drying is 3 to 30 parts by weight. 13. The method for continuously manufacturing a laminate according to item 13. (17) Claims 6 or 9 to 1, wherein the sheet-like base material is paper mainly composed of cellulose fibers.
A method for continuous production of a laminate as specified in any of Clause 6. (18) The continuous production method of a laminate as defined in claim 4 or any one of claims 9 to 16, wherein the curing catalyst is an aliphatic peroxide. (19) The continuous production method of a laminate according to claim 18, wherein the aliphatic peroxide is an aliphatic peroxyester. (20) The polymerizable monomer used for crosslinking the thermosetting resin is styrene and/or a styrene derivative, or a mixture of these and divinylbenzel. A method for continuously manufacturing a laminate as defined in any one of Items 9 to 16. (21) The thermosetting resin is an unsaturated polyester resin that is liquid at room temperature, and the cured product thereof has a glass transition temperature of 20 to 80°C.
A method for continuously producing a laminate as defined in any of Items 17 to 17. (22) The sheet-like base material is impregnated using a single-sided impregnation method in which the resin liquid flows down from above the base material. Continuous body manufacturing method. (23) The rigidity value of the film-like or sheet-like covering is E
・d^3 (E is the bending elastic modulus Kg/cm^2, d is the thickness c
A method for continuously manufacturing a laminate as defined in any one of claims 1 to 3 and 9 to 17, wherein the weight is 3×10^-^3Kg·cm or more when expressed as m). (24) The surface roughness of the film-like or sheet-like coating, expressed as Rmax, is approximately 0.4 microns or more and approximately 5 microns or less.
A continuous manufacturing method for a laminate as defined in either paragraph or paragraph 23. (25) Any one of claims 2, 3, and 9 to 17, wherein the metal foil is laminated by continuously supplying an adhesive between the metal foil and the base material impregnated with a resin liquid. Continuous manufacturing method for laminates specified in the above paragraph. (26) Claim 25, wherein the adhesive is supplied by continuously applying it to the surface of the metal foil before laminating the metal foil.
2. Continuous manufacturing method of the laminate described in 2. (27) The continuous production method of a laminate according to claim 26, wherein the metal foil coated with the adhesive is subjected to a coating film heat treatment step before being laminated. (28) The adhesive does not substantially contain components removed by drying such as solvents, and does not substantially generate gaseous or liquid reaction by-products during the curing reaction process of the adhesive. 26. The continuous production method of a laminate according to claim 25, wherein the molding pressure is substantially no pressure when the adhesive adheres to the resin liquid-impregnated laminate substrate and cures together. (29) The thermosetting resin liquid is an unsaturated polyester resin that is liquid at room temperature, and the adhesive is an amine-oxidized epoxy resin. Claim 2 uses one or more peroxides selected from the group of esters or dialkyl peroxides.
A method for continuously producing a laminate as defined in any of Items 5 to 28. (30) A patent claim in which a compound having both a copolymerizable unsaturated double bond and an epoxy group is interposed near the joint between the resin liquid-impregnated laminated base material and the adhesive applied to the metal foil and then cured. The method prescribed in any of paragraphs 25 to 28. (31) The metal foil passes through a step of continuously drying adhering moisture before applying the adhesive.
The method described in section. (32) The method according to claim 25, wherein the metal foil undergoes a step of continuously applying a surface treatment agent before the drying step. (33) The method according to claim 32, wherein the surface treatment agent is a silane coupling agent. (34) The method according to claim 1, wherein the pressure reduction treatment is performed by squirting the resin liquid into a container whose pressure is reduced to 30 mmHg or less and accumulating it at the bottom of the container. (35) The elongated laminate is cut into practical dimensions during curing and is further cured after cutting.
The method specified in any of paragraphs 9 to 16. (36) Film-like or sheet-like coatings are laminated in multiple stages on both sides of the resin liquid-impregnated laminated base material and sandwiched between the resin liquid-impregnated base materials, cured, and cut, and then the intermediate coating is separated. A method according to any one of claims 1 to 3, in which a laminate is separated into upper and lower parts and a large number of laminates are obtained at the same time. (37) The method defined in any one of claims 1 to 3, wherein the coating passes through a step of continuously applying a mold release agent to the entire surface or both edges. (38) The method defined in any one of claims 1 to 3, wherein the coating is continuously peeled off and wound up and recovered after the laminate is cured. (39) The coating is an endless belt and is continuously peeled off after the laminate is cured.
The method prescribed in any of the paragraphs. (40) The method according to claim 1, wherein the weight ratio of the resin liquid amount of the resin liquid-impregnated base material to the impregnated base material is 30 to 70%.