JPH01286854A - Continuous manufacture of laminate - Google Patents

Abstract

PURPOSE:To make a continuously a laminate, whose high-frequency property is favorable by enabling adjustment into the moderate resin content, by a method wherein side chain double bond type resin containing resin solution is cured under pressurization by making use of the same. CONSTITUTION:A drawing-out device 1 of a base material A, pretreatment device 2 of the base material, a drying machine 3, an impregnating device 4 of a curing resin solution, squeeze rolls 5, a double endless belt press device 7d having a pairs of pressurizing rollers group, a drawing-out device 8 of a mold release film or a metallic foil, a cutting device 9 of a laminate C and a heating and curing furnace 10 are made principal parts. Although the double endless belt press is exemplified before, as a pressurizing device at the time of curing, structure where a belt moves forward in a vertical direction of a laminated body B while performing surging vertically is favorable as the structure of the other preferable double endless belt press. It is considered that the belt of a pressurizing part advances within a heating and curling furnace 12 through the directional control roller groups 11, 11... arranged zigzag, the laminated body B placed between the directional control roller groups is moved forward in the vertical direction by performing surging and a squeezing effect at a directional control part of the belt is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for continuously manufacturing laminates, and in particular, to continuously and efficiently manufacture laminates suitable for various electrical insulation laminates and printed circuit board laminates. related to the method of production.

[Prior Art] Attempts to continuously manufacture laminates have been made for a long time, and examples using unsaturated polyester resin include U.S. Pat.
JP-A-47-14255 is an example using a double belt press device which presses the laminate from above and below via an endless belt.

However, unsaturated polyester resins generally have a relatively low molecular weight of 3000 to 5000,
The conditions for molding into a laminate are in many cases virtually no pressure, suppressing excessive flow and outflow of the impregnated resin in the base material, and in the case of heating and pressing, a special unsaturated polyester resin is used. There are many examples where the prepreg state is used. Therefore, when the above-mentioned substantially no-pressure condition is used, the resin content in the laminate tends to increase, which tends to cause a decrease in the hot rigidity of the obtained laminate.

Recently, a laminate using a side chain double bond type resin made of 1,2 polybutadiene has been developed and put into practical use for applications where high frequency characteristics are important.

When a side chain double bond type resin containing 1.2 polybutadiene as a main component is used in a laminate, its high frequency properties are excellent, but the moldability cannot necessarily be said to be excellent.

In other words, 1.2 All polybutadienes are viscous liquids, so in order to improve their impregnation properties, it is necessary to dilute them with a solvent such as toluene to lower their viscosity. It is customary to evaporate the post-solvent to form a prepreg, and then laminate and cure it. Furthermore, since the curing speed is slow, in order to cure the laminate and obtain an excellent laminate, it is necessary to
It was necessary to use harsh conditions such as a temperature of 0° C. or higher and a high pressure of 10 kg/c or higher.

The poor moldability of these 1.2 polybutadienes results in problems in reducing the manufacturing cost of laminates.

[Problem to be solved by the invention] Based on the above circumstances, we focused on the good high-frequency characteristics of side chain double bond type resin, and created a new resin that can be adjusted to an appropriate resin content and allows continuous production of laminates. There was a need for a continuous manufacturing method for laminates using .

[Means for Solving the Problems] The present invention was made in view of the above circumstances, and the impregnating liquid using the side chain double bond type resin applied to the present invention has excellent high frequency characteristics and has a relatively high molecular weight. However, the present invention was completed based on the discovery that the impregnation property is good and that the resin/substrate weight ratio can be easily controlled by changing the molding conditions. That is, the gist of the present invention is, firstly, by continuously conveying a plurality of elongated base materials, impregnating the base materials with a curable resin liquid, then laminating them, and curing and cutting the laminate. A method for continuous production of laminates characterized in that a resin composition containing a side chain double bond type resin as a main component is used as a curable resin liquid and is cured under pressure, Second, the pressurization and curing,
The present invention is a method for continuous production of a laminate, in which the laminate is passed through a group of direction changing rollers arranged in a staggered manner and undulated in the upper and lower directions.

Hereinafter, the content of the present invention will be explained in detail.

The side chain double bond type resin referred to in the present invention is a polymer consisting of a main chain and a side chain, where the main chain is a backbone polymer containing a vinyl monomer unit having a functional group, and the side chain is a backbone polymer containing a vinyl monomer unit having a functional group. It is a side chain double bond type resin that is a branch having a radically reactive carbon-carbon double bond formed through a functional group, and the vinyl monomer unit that makes up the main chain is The vinyl monomer unit is an essential unit, and if necessary, a vinyl monomer unit without a functional group is included, and these polymerize to form the main chain.

Monomers constituting the above essential units include acrylic acid,
Vinyl monomers having a carboxyl group as a functional group such as methacrylic acid, maleic anhydride, and maleic acid monoester, vinyl monomers having a glycidyl group as a functional group such as glycidyl methacrylate, glycidyl acrylate, etc. Allyl alcohol, 2-hydroxy Typical examples include vinyl monomers having a hydroxyl group as a functional group, such as ethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, and N-methylol acrylamide, especially acrylic acid and methacrylate. Acids are most preferably used.

In the present invention, the vinyl monomer unit having a functional group may be present as an active functional group when the main chain is formed by polymerization, or may be polymerized by reacting the side chain described below with the functional group of the monomer in advance. It refers to a type of vinyl monomer unit that has a functional group that serves to connect a side chain to the main chain, regardless of whether it is attached to the main chain.

Examples of vinyl monomers without functional groups include styrene,
α-methylstyrene, chlorostyrene, vinyltoluene, vinyl chloride, vinylidene chloride, vinyl bromide, acrylonitrile, ethylene, propylene, butadiene, acrylic ester, methacrylic ester, vinyl acetate, vinyl propionate, diester maleate, ethyl vinyl Examples include benzene.

The weight average molecular weight of the main chain composed of these vinyl monomer units is from 5,000 to 400,000, preferably from 10,000 to 200,000. This value is appropriately selected depending on the type of side chain. This molecular weight affects the physical properties of a laminate such as a printed circuit board and its impregnating properties; if it is less than 5,000, the mechanical properties of the laminate after curing will be insufficient; if it exceeds 400,000, ) is poor in resin impregnation, and both are unfavorable.

The amount of monomer units having functional groups in the main chain is related to the density of the side chains, and since it affects the curing reactivity between the side chains, an appropriate ratio is selected. 1~
2 mol is preferred, more preferably 0.4 to 1.5 mol.

The side chain referred to in the present invention refers to a chain having a >C-C double bond at the end or in the middle, and which forms a branch on the main chain via its functional group. Examples of general formulas include the following.

(1) In the formula, R1 to R3 are hydrogen or a methyl group, and n
represents an integer from O to 5, (n) in the formula, R4 is hydrogen or a methyl group, L and L2 represent 10- or -NH-, Xl and X2
is a hydrocarbon group having 2 to 16 carbon atoms, and the carbon atom bonded to it is a primary or secondary carbon, and B is an aliphatic, alicyclic or aromatic hydrocarbon group having up to 20 carbon atoms. be.

(III) In the formula, R5 is hydrogen or a methyl group.

Note that the side chains of the side chain double bond type resin according to the present invention are not limited to these, and any type that can form crosslinks between side chains by a radical reaction using a nyl monomer and a crosslink can be applied.

Next, a manufacturing example of the side chain double bond type resin used in the present invention will be explained.

A method for producing a curable prepolymer for impregnation resin having a side chain represented by the general formula (I) in the main chain is as follows.

(+) First, a desired amount of (meth)acrylic acid (component forming a functional group) and an epoxy resin in an excess equivalent ratio to the (meth)acryloyl group are mixed with a necessary reaction catalyst, such as a third
An unsaturated group-containing epoxy resin (A) containing a (meth)acryloyl group and an epoxy group in one molecule is produced by reacting a class amine, an amine salt, a quaternary ammonium salt, and a metal salt.

(it) Then, after adding the required type and amount of vinyl monomer (component without functional groups), the unsaturated group-containing epoxy resin (A) is prepared in the presence of an initiator such as azobisisobutyronitrile. By radically polymerizing the (meth)acryloyl group and the vinyl monomer, a reaction mixture containing a prepolymer having an epoxy group in the side chain can be obtained.

(iii) Furthermore, by adding the required amount of (meth)acrylic acid and causing the epoxy groups and carboxyl groups remaining in the reaction mixture of (It) to react, vinyl unsaturation is achieved at the end of the desired side chain. Curable prepolymers with any number of groups can be obtained.

Typical examples of the above epoxy resin include bisphenol A
There is a phenylglycidyl ether type polyaddition homolog synthesized from shrimp chlorohydrin and shrimp chlorohydrin. Its chemical structural formula is represented by, for example, the following general formula (IV).

(IV) In the formula, R1 and R2 are hydrogen or a methyl group, and n is 0
It is an integer of ~5.

Note that n is preferably 0 to 3.

When synthesizing an unsaturated group-containing epoxy resin, the ratio of (meth)acrylic acid to epoxy resin is 1 part (meth)acrylic acid
It is necessary to use at least 1 mol of an epoxy resin having two or more glycidyl ether type epoxy groups in one molecule per mole (that is, per equivalent of carboxyl group).

Furthermore, as another method, a vinyl monomer having no functional group and (meth)acrylic acid are copolymerized to form a main chain, and then the epoxy group in the unsaturated group-containing epoxy resin (A) is converted into a functional group of the main chain. It is also possible to obtain a curable prepolymer having an unsaturated (meth)acryloyl group at the end of the side chain by carrying out an esterification reaction with a certain carboxyl group.

Examples of the method for producing a curable prepolymer for impregnation resin having a side chain represented by the general formula (n) in the main chain include the following.

(i) A (meth)acrylic monomer containing a hydroxyl group is used as one component, and if it does not have the above-mentioned functional group, it is copolymerized with a nil monomer to synthesize a main chain having a hydroxyl group as a functional group.

(11) Separately, an unsaturated group-containing monoalcohol having a (meth)acryloyl group and a diisocyanate were mixed in a ratio of 1.2:1 (
molar ratio) to synthesize an unsaturated group-containing isocyanate that shares a free isocyanate group and a (meth)acryloyl group in one molecule of the reaction product.

(Mountain) The hydroxyl group-containing main chain obtained in (i) and (11) above is reacted with an unsaturated group-containing isocyanate in a crosslinking vinyl monomer or a solvent solution.

When a solvent is used, it is necessary to remove the solvent by any known method to obtain a prepolymer solution.

As a monomer having a hydroxyl group, the former S self (
meth)acrylic monomers 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2
Typical examples include -hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and methylol acrylamide.

Solution polymerization is convenient for the polymerization in step (i), and the process can proceed to the next step as it is, but it is also possible to dissolve the polymer obtained by pearl polymerization or bulk polymerization in a monomer and use it for the next reaction. It's practical.

Typical commercially available diisocyanates include 2.4-) lylene diisocyanate;
2,4-tolylene diisocyanate (80% by weight) and 2
．． Mixed isocyanates with 8-tolylene diisocyanate (20% by weight), diphenylmethane diisocyanate, hexamethylene diisocyanate, ■, 5-naphthylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated diphenylmethane Examples include diisocyanate and hydrogenated xylylene diisocyanate.

The reaction is carried out by dissolving the isocyanate in a solvent or a vinyl monomer for crosslinking, and adding the unsaturated group-containing alcohol dropwise.

When a solvent is used, it is usually necessary to replace the solvent with a crosslinking vinyl monomer, which is accomplished by fractional distillation taking advantage of the boiling point difference (the solvent has a lower boiling point). In the case of a vinyl monomer solution for crosslinking, it can be used as is.

Examples of the method for producing a curable prepolymer for impregnation resin having a side chain represented by the general formula (III) in the main chain include the following method.

(1) Copolymerize the vinyl monomer that does not have the aforementioned functional group with glycidyl (meth)acrylate, and in the next step, (meth)acrylic acid in substantially the same molar amount as the epoxy group contained in this copolymer resin. is added to cause the epoxy group to react with the carboxyl group.

(II) Still another method is to copolymerize the above-mentioned vinyl monomer having no functional group and (meth)acrylic acid, and in the next step, the mole is substantially equivalent to the carboxyl group contained in this copolymer resin. of glycidyl (meth)acrylate is added to cause the carboxyl group to react with the epoxy group.

For example, a styrenic monomer represented by the general formula (V) [wherein R6 represents hydrogen or a methyl group, and X3 represents a phenyl group, an alkylphenyl group, or a halogenated phenyl group] does not have the above-mentioned functional group. By using it as a vinyl monomer, a curable prepolymer of general formula (VI) can be obtained.

OHC (Vl) In the formula, R and X have the same meanings as above, R7 and R represent hydrogen or a methyl group, and m1 and nl represent positive integers.

The copolymerization, which is the first step in the production methods (1) and (11), can be carried out by solution polymerization, bar polymerization, etc., but in the case of solution polymerization, it is used as it is for the reaction in the next step. In the case of bar polymerization, the resulting copolymer is dissolved in a solvent or a crosslinking monomer before being used in the next reaction step.

Copolymerization of styrenic monomer and glycidyl monomer,
Alternatively, when copolymerizing styrenic monomers with methacrylic acid or acrylic acid, known radical polymerization catalysts,
For example, it can be easily carried out by using an organic peroxide, an azo compound, etc. and selecting an appropriate polymerization temperature.

In the present invention, the polymerization rate in the copolymerization step does not necessarily have to be 100%; for example, it is possible to stop at 80% and proceed to the next step while containing the residual monomer. This is one of the advantages of side chain double bond type resin.

That is, in the next step, the general formula (■ ) [In the formula, R and R10 represent hydrogen or a methyl group] A divinyl compound having a diacryloyl structure or a dimethacryloyl structure is produced, but the coexistence of this divinyl compound up to a certain amount is not considered in the present invention. The physical properties of the copolymer resin after polymerization are not impaired in any way.

Furthermore, it is obvious that the residual styrene monomer does not pose any problem in the present invention as will be described later.

Next, in the reaction of the second step, it is preferable to use an appropriate polymerization inhibitor, such as hydroquinone, in order to prevent polymerization of the residual styrene monomer and crosslinking reaction between the copolymer resins.

The amount of epoxy group or carboxyl group added and reacted with respect to 1 equivalent of carboxyl group or epoxy group contained during the reaction of this second step is 0.9 to 1.1 equivalent,
It is preferably 0.95 to 1.05 equivalent.

As the crosslinking vinyl monomer used with the side chain double bond type resin referred to in the present invention, any known radically reactive vinyl monomer used for crosslinking can be used, but among these, styrene, α-methyl styrene, p
-Substituted styrenes such as methylstyrene, p-chlorostyrene, p-vinylstyrene; methyl niaacrylate, ethyl acrylate, butyl acrylate, acrylic acid-2-
Various (meth)acrylic acid esters such as ethylhexyl, methyl methacrylate, ethyl methacrylate, butyl methacrylate, lauryl methacrylate, and benzyl methacrylate: ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol di Vinyl polyfunctional (meth)acrylates such as acrylate, 4-butanediol dimethacrylate, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate: polyurethane (
Vinyl polyfunctional oligoesters such as meth)acrylate and polyether (meth)acrylate are included.

Also, dibutyl maleate, dioctyl maleate, phenylmaleimides, vinyl acetate, vinyl propionate,
Divinylbenzene and its derivatives, diene compounds such as cyclopentadiene and butadiene, divinyl ester compounds, divinyl urethane compounds, etc. can also be used.

In particular, it is preferable to use a mixture of the above-mentioned monofunctional monomers and polyfunctional monomers as crosslinking monomers and polyfunctional monomers because the heat resistance is further improved. The above-mentioned polyfunctional monomer must be a compound that can be copolymerized with the above-mentioned monofunctional monomer, and those that form a uniform copolymer are particularly preferred. The ratio of polyfunctional monomer to monofunctional monomer is preferably 5.
-50% by weight, more preferably 10-40% by weight.

The content of the side chain double bond type resin in the impregnating liquid according to the present invention is usually 10 to 60% by weight, and the vinyl monomer for burning and crosslinking can be contained up to 90% by weight. When the resin content is less than 10% by weight, the viscosity of the impregnating liquid becomes too low, which tends to impair moldability, reduce crosslinking density, and reduce punchability, heat resistance, and solvent resistance of the laminate. or,
If it exceeds 60% by weight, the viscosity tends to increase too much and impregnating properties tend to decrease.

Flame retardancy is sometimes required for electrical laminates, and in addition to additive flame retardants such as hexabromobenzene, a reactive halogen-containing flame retardant vinyl monomer is added separately from the crosslinking vinyl monomer. This is particularly preferable in terms of resin physical properties as well as flame retardant requirements.

Preferably used halogen-containing flame-retardant monomers include monoglycidyl methacrylate, an esterified product of a polyhydric alcohol having an aliphatic or alicyclic saturated hydrocarbon group containing bromine or chlorine having 1 to 18 carbon atoms, and a saturated polybasic acid. Or a halogen-containing flame-retardant monomer (1) obtained by addition reaction with monoglycidyl acrylate, general formula (■).

A bromine-containing flame-retardant monomer (2) represented by (IX).

(3) is mentioned.

In the general formula, R11' R1□ and R13 represent hydrogen or a methyl group.

The polyhydric alcohol used in the synthesis of the flame retardant monomer (1) is preferably an aliphatic or alicyclic alcohol having 1 to 12 carbon atoms, and an easily available example is dibrome neopentyl glycol. Yes, but not limited to this.

Further, the flame retardant monomers (2) and (3) can be synthesized by an esterification reaction between dibrome neopentyl glycol and (meth)acrylic acid. The type and proportion of these flame-retardant monomers to be added are selected according to the requirements for making the laminate plate flame-retardant, but it is preferable to add them to the impregnating liquid in an amount of 5 to 70% by weight. If it is less than 5% by weight, no improvement in flame retardancy can be expected, and if it exceeds 70% by weight, physical properties other than flame retardancy will deteriorate, which is undesirable.

When producing a laminate using paper as a base material, if the halogen content in the impregnating liquid is approximately 105 or more in terms of bromine, the UL-94-V
- Passes the standard of 0. Note that it is even more effective when 5b2o3 is used in combination.

Aliphatic or alicyclic bromine compounds are known.

On the other hand, it is said that chlorine provides about 1/2 the flame retardancy of bromine, and the inventors attempted to introduce a more stable chlorine compound into the resin composition, and found that the general formula ( Chlorine-containing flame-retardant monomer (4) represented by X)
was found to be effective.

[In the formula, R is hydrogen or a methyl group, and n2 is 1-1
Represents an integer of 0. ] This flame-retardant monomer (4) can be synthesized by ring-opening polymerization of epichlorohydrin using a boron trifluoride ether complex catalyst in the presence of acrylic acid or methacrylic acid.

For this synthesis reaction, it is preferable that 02 not exceed 1O.

In addition, the value of flame retardant effect is 0.45 when bromine is 1.
The value is ~0.50, which corresponds to the commonly said index.

In particular, this flame retardant monomer (4) is preferably used in combination with the above-mentioned flame retardant monomers (2) and/or (3), and is added in a total amount of 5 to 70% by weight in the impregnating liquid. It is preferable that If it is less than 5% by weight or more than 70% by weight, it is not preferred as in the case of flame retardant monomers (1) to (3).

These flame retardant monomers (1), (2), (3)
, (4) are reactive, so they do not migrate from the cured resin, and the viscosity of the impregnating liquid can be easily adjusted.
Setting the molecular weight of the polymer having a side chain represented by m),
Also, when used in the main chain, the type of nil monomer can be easily selected.

Another effect of the chlorine-containing flame-retardant monomer (4) is that since it is a polyether derivative, it imparts flexibility to the cured resin, thereby improving impact resistance.

Furthermore, for the purpose of improving impact resistance, a flexibility-imparting monomer represented by general formula (XI) may be added to the curable composition as a crosslinking vinyl monomer.

C0O-R16-0+COCH2CH2CH2CH2C
to H2O 3R1□(XI) [In the formula, R1 is hydrogen or a methyl group, R16 is a divalent aliphatic hydrocarbon group having 2 to 5 carbon atoms, and R1□ is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms. , R3 means a positive integer of 1 to 15. ] Such flexibility-imparting monomers are typically produced by reacting (meth)acrylic acid with ethylene oxide, propylene oxide, or tetrahydrofuran, and then forming ε-
Obtained by addition reaction with caprolactone.

Specific examples thereof include ε-caprolactone adducts of hydroxyethyl (meth)acrylate and ε-caprolactone adducts of hydroxypropyl (meth)acrylate.

The amount of the flexibility-imparting monomer used is in the range of 0.1 to 40% by weight based on the total amount of crosslinking vinyl monomers.

If it is less than 0.1% by weight, the impact resistance improvement effect is small;
If it exceeds 0% by weight, the rigidity will be significantly lowered.

The side chain double bond type resin composition according to the present invention can be cured using a general-purpose organic peroxide.

Further, known curing catalysts such as curing catalysts sensitive to light and curing catalysts sensitive to radiation and electron beams can also be used together with organic peroxides or alone.

Furthermore, the radically curable composition may optionally contain additives such as plasticizers, flame retardants, fillers (for example, particles of antimony trioxide, aluminum hydroxide, etc.), stabilizers, lubricants, etc.
Various additives such as inorganic pigments, reinforcing materials, coloring agents, mold release agents, curing agents, and curing accelerators can be included.

The radically curable composition according to the invention can be used in the production of circuit laminates according to known mechanical methods. That is, a sheet-like base material is impregnated with the curable composition of the present invention, and a plurality of impregnated base materials are laminated (for example, 2 to 20 sheets).
A laminate can be obtained by heating under pressure and hardening and molding.

The base material for impregnation in the present invention is conventionally used glass fiber cloth, glass nonwoven cloth, etc., paper mainly made of cellulose fibers such as kraft paper, linter paper, asbestos cloth, etc. Examples include inorganic fiber-based sheet or band-like materials.

In this case, the paper yarn has a density (bulk specific gravity) of 0.3 to 0.7 g/c when air-dried, from the viewpoint of impregnation and quality.
Paper mainly composed of cellulose fibers, such as kraft paper, is preferable.

The water resistance of these base materials can be improved by pre-impregnating and drying them with a treatment agent such as a silane coupling agent, methylol melamine, methylol phenol, methylol guanamine, or N-methylol compound before impregnating them with the impregnating liquid. , is preferable because electrical characteristics can be improved by reducing hygroscopicity.

In particular, when using a paper base material, a treatment agent consisting of 20 to 80% by weight of a modified N-methylol compound (component A) and 80 to 20% by weight of an unmodified N-methylol compound (component B) and ignition. The impregnation and drying treatment is preferable because it allows a laminate with well-balanced electrical properties and impact resistance to be obtained.

Examples of the N-methylol compound include melamine formaldehyde resins, guanamine formaldehyde resins such as acetoguanamine and benzoguanamine, and cyclic urea resins such as urea formaldehyde resins, ethylene urea formaldehyde resins, and dihydroxyethylene urea formaldehyde resins.

The molar ratio of formaldehyde used for these methylolations is 2 to 6 mol, preferably 2 to 3 mol in the case of melamine, and 2 to 4 mol, preferably 2 to 3 mol in the case of urea.
It is a mole.

The modifier for modifying the N-methylol compound is one or more of hydroxyl groups, epoxy groups, amino groups, and carboxyl groups that are reactive with methylol groups, and at the same time reactive with the side chain double bond type resin. Compounds containing unsaturated groups are used.

These compounds include 2-hydroxylethyl acrylate, 2-hydroxylethyl methacrylate, acrylic glycidyl ether, glycidyl methacrylate, ethylene glycol monoallyl ether, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, glycerin diallyl ether, ethylene glycol (meth) Acrylic acid and oxyacid esters such as: These modifiers are added at 6 to 15 mol to the N-methylol compound, at a pH of 2 to 7, and at a temperature of 50 to 80°C.
, and a reaction time of 30 minutes to 4 hours to obtain a modified product.

After the reaction is completed, excess modifier is removed by vacuum distillation, and the active ingredient is adjusted to about 60% by weight with methanol and water.

Component B, which is an unmodified N-methylol compound, has a molar ratio of formaldehyde used for methylolation of 2 to 6 mol, preferably 2 to 3 mol, in the case of melamine, and 2 to 4 mol, preferably 2 to 4 mol, in the case of urea. A compound that is methylolated at 3 moles and is not methyl-modified is used.

This paper base treatment agent has a ball weight of 40 to 70% for both A and B components.
of solid content is used, and the ratio is A on a solid content basis.
A paper base material is impregnated using a combination of 20 to 80% by weight of component B and 80 to 20% by weight of component B.

The manufacturing method according to the present invention can also be applied to manufacturing a metal foil-clad laminate in which metal foils are laminated together.

As the metal foil for lamination, there is electrolytic copper foil intended for use in printed circuit boards, and it is preferable to use this from the viewpoints of corrosion resistance, etching properties, and adhesive properties, but electrolytic iron foil and aluminum foil are also available. used.

A metal foil having a thickness of 10 to 100 μm is usually used.

Further, the adhesive surface of the metal foil is preferably roughened for the purpose of improving adhesiveness.

In order to effectively achieve adhesion between the metal foil and the resin-impregnated substrate, it is preferable to use an adhesive, and the adhesive may be a liquid or semi-solid adhesive that does not generate unnecessary reaction by-products during the curing process. Fluid, i.e. viscosity preferably 5
Adhesives having a pressure of 000 poise or less are suitable. From this viewpoint, for example, epoxy-acrylate adhesives, epoxy resin adhesives, polyisocyanate adhesives, or various modified adhesives thereof are suitable. As the epoxy resin adhesive, a mixture of a bisphenol A type epoxy resin and a curing agent such as a polyamide resin or amines is suitable.

By introducing such an adhesive, the adhesive strength of metal foil is excellent,
In addition, metal foil-clad laminates with excellent solder heat resistance and electrical insulation properties can be manufactured.

When the adhesive is used in a state where it is applied to metal foil, it may be precured to a semi-cured state by heat treatment at 60 to 150° C. for 2 to 7 minutes after application.

The thickness of the laminate of the present invention varies depending on the type of substrate, the composition of the curable composition, the use of the laminate, etc., but is usually 0.5 to 3.
A value of 0 is preferred.

Hereinafter, production examples of the side chain double bond type resin used in the present invention will be described in detail.

Throughout this specification, all temperatures are in degrees Celsius, and parts and percentages are by weight unless otherwise specified.

Further, the curable prepolymers and halogen-containing flame-retardant monomers used in the examples are also shown below.

Prepolymer 1-1 A separable flask (3000ml) equipped with a stirrer, a thermometer with a gas inlet tube, a reflux condenser, and a dropping funnel.
), methacrylic acid (30 g, 0.41 mol), methyl ethyl ketone (400 g), styrene monomer (800 g,
g, 7.7 mol), azobisisobutyronitrile (
5.0 g) and dodecyl mercaptan (12 g) were charged, and polymerization was carried out at 75 to 80° C. for 10 hours in a nitrogen atmosphere. Hydroquinone (0.5 g) was added to inhibit polymerization. The polymerization rate of styrene monomer was 76%, and the polymerization rate of methacrylic acid was 93%, and a polymer-containing liquid containing a styrene-methacrylic acid copolymer having a weight average molecular weight of about 50,000 was obtained.

In addition, in another reactor with the same configuration as above, "Epicoat 11
27J (trade name of epoxy resin, manufactured by Yuka Shell Co., Ltd.)
(360g, 1 mol), methacrylic acid (138g
.

1.6 mol), benzyldimethylamine (1.2 g),
Rose benzoquinone (0.12 g) was charged and reacted at 120° C. for 3 hours under a nitrogen atmosphere. After the reaction, the acid value became almost zero, and a vinylation reagent containing an epoxy resin containing an unsaturated group was obtained. Add the entire amount of the previously prepared polymer-containing liquid to the vinylation reagent, and add triphenylphosphine (5 g),
Rosebenzoquinone (0, LOg) was added and heated, the methyl ethyl ketone solvent was distilled off at a boiling point of 110°C, and the mixture was reacted at the same temperature for 5 hours.

After the reaction, the unsaturated group-containing epoxy resin is about 1
It became 5%. Heat evaporation was continued at 30-50 mmHg while adding styrene monomer (1000 g) intermittently. Methyl ethyl ketone detected from the distillate is 0.
The operation was terminated when it became 1% or less.

The resin liquid containing the curable prepolymer thus obtained contains a side chain double bond type resin having the side chain represented by formula (I), has a nonvolatile content of 52% by weight, has a viscosity of 6.2 voids (2
It was a yellowish brown liquid at a temperature of 5°C.

Prepolymer I-2 A separable flask (5000ml) equipped with a stirrer, a thermometer with a gas inlet tube, a reflux condenser, and a dropping funnel.
) were charged with methacrylic acid (35 g, 0.41 mol), ethyl acrylate (600 g, 6 mol), methyl ethyl ketone (600 g), and dodecyl mercaptan (6 g), and heated to 75° C. under a nitrogen atmosphere.

A solution of azobisisobutyronitrile (5 g) dissolved in 50 ml of methyl ethyl ketone was added from the dropping funnel so that the internal temperature was 80° C. or lower. It was made to react at 75-80 degreeC for 8 hours. Thereafter, the temperature was raised to 180°C, and methyl ethyl ketone and a very small amount of unreacted ethyl acrylate were distilled off. The obtained polymer weighed 831 g and had a weight average molecular weight of 70,000.

In addition, another reactor (2000 ml) with the same configuration as above was used with "Epicote 827" (trade name of epoxy resin).

(manufactured by Yuka Shell Co., Ltd.) (360 g, 1 mol), methacrylic acid (138, 1.8 mol), benzyldimethylamine (1,2+r), rosebenzoquinone (0,1
2g) was charged and reacted at 120°C under a nitrogen atmosphere for 3 hours.

The acid value of the reaction solution became almost zero, and a vinylation reagent containing an unsaturated group-containing epoxy resin was obtained.

Styrene monomer (1000 g) was added and dissolved in this vinylation reagent, and this was added to the previously prepared flask containing the polymer. Plus triphenylphosphine (5g)
and rosebenzoquinone (0.1Of) and heated,
The reaction was carried out at 120°C for 4 hours.

After the reaction, the unsaturated group-containing epoxy resin is about 13
%Became.

The thus obtained resin liquid containing the curable prepolymer has a viscosity of 8.9 poise (at 25°C) and has a non-volatile content of 53% by weight, including the side chain double bond type resin having side chains of type (I).
It was a yellowish brown liquid.

Prepolymer n-1 Has a molecular weight of approximately 40,000, is composed of styrene and 2-hydroxyethyl methacrylate, and has a main chain (heavy; ratio 82%) and 2
- Hydroxypropyl methacrylate - Contains a side chain double bond type resin having a side chain. ) [-R in Slaughter (II)
is a methyl group, and X is -CH2-CH2+.

■ Acrylic acid (72 sr.
, 1 mol), ethyl acrylate (800 g, 8 mol), acrylonitrile (53 g, 1 mol), methyl ethyl ketone (700i), dodecyl mercaptan (
10 g) and heated to 75° C. under a nitrogen atmosphere.

Azobisisobutyronitrile (5 g) was dissolved in methyl ethyl ketone (50 g), and this solution was added dropwise from the dropping funnel over about 1 hour to bring the temperature inside the reactor to 75-80°C.
It was added while maintaining the After the addition of the catalyst was completed, the reaction was continued at the same temperature for 8 hours.

Next, the inside of the reactor was heated to 180° C. to distill off methyl ethyl ketone along with a small amount of unreacted monomer.

The amount of polymer obtained in the reactor (flask) was 920 g. The 1112 average molecular weight of this polymer was 40,000.

Glycidyl methacrylate (142 g
, 1 mol) and styrene (looOFC) were added, and rosebenzoquinone (0.2 g) and triphenylphosphine (4 g) were added, followed by reaction at 100° C. for 5 hours. Approximately 88% of glycidyl methacrylate was esterified. The resulting resin liquid containing the radically curable prepolymer was a yellowish brown liquid containing a side chain double bond type resin having a side chain represented by formula 2 (III), and had a nonvolatile content of 53%, with a viscosity of 7.1 poise (25 ℃).

Prepolymer m-2 Styrene (3CIOr), glycidyl methacrylate (45,
4 g), benzoyl peroxide <3-5 g), and n-dodecyl mercaptan (3.5 g). Styrene (TS3g), glycidyl methacrylate (45°C), benzoyl peroxide (1.8g), n-dodecyl mercaptan (1,
8g) of the mixture was added dropwise, and the mixture was further reacted at 115°C for 1.5 hours. As a result, the reaction rate of styrene was 48%, the reaction rate of glycidyl methacrylate was 76%, and a colorless and transparent copolymer solution was obtained.

When acrylic acid (49.0 g) and hydroquinone (0.5 s-) were added to this solution and reacted for 4 hours at 100°C, the reaction rate of acrylic acid was 90%.
II) A pale yellow transparent resin solution containing a side chain double bond type resin having a side chain represented by the formula was obtained.

Prepolymer m-3 Methyl ethyl ketone (199sr) was put as a solvent into a separable flask (10100O) equipped with a stirrer, a thermometer with a gas inlet tube, a reflux condenser, and a dropping funnel, and then styrene (52.0g, 0.5 mol), glycidyl methacrylate (14.2 g, 0.1 mol), benzoyl peroxide (0.52 g), and dodecyl mercaptan (0.52 s-), and reacted at 85 to 90°C for 5 hours under nitrogen blowing. However, the polymerization rate of styrene is 62% and that of glycidyl methacrylate is 73%.
Met. The solvent and unreacted monomers were removed using a rotary evaporator to obtain a white polymer.

A 45% solution of the above copolymer in styrene was added to the same apparatus as above, and then methacrylic acid (6,
4g), hydroquinone (0.04g) and 10
When the reaction was carried out at 0°C for 5 hours, the reaction rate of methacrylic acid was 94%.

This resin liquid contained a side chain double bond type resin having a side chain represented by the above formula (III), was pale yellow, and had a viscosity at 25° C. of 5.6 poise.

Room-temperature gelation test by adding Vercure 5AJ (trade name 1 manufactured by Nippon Oil & Fats Co., Ltd., peroxide catalyst, 1 part) and cobalt naphthenate (6% Co, 0.5 part) to 100 parts of the above resin solution. As a result, the gelation time was 13 minutes, the shortest curing time was 15.3 minutes, and the maximum exothermic temperature was 149°C.

Furthermore, the cured resin had the following physical properties and was excellent in transparency.

Tensile strength 6.5kg/ml1i bending strength
12.8 kg/ma Bending elastic modulus 314 kg/a + 4 Heat deformation temperature 120°C Prepolymer 11-4 Using the same equipment used to produce prepolymer m-2, methyl ethyl ketone (199 g) was added as a solvent,
Then styrene (52.0 g, 0.5 mol), methacrylic acid (17.2, 0.2 mol), benzoyl peroxide (0.52 g), dodecyl mercaptan (0.5 mol),
, 52g) and reacted for 4 hours at 105-110℃ under nitrogen blowing conditions, the polymerization rate of styrene was 6.
The polymerization rate of methacrylic acid was 68%. Styrene was further added to this, and only methyl ethyl ketone was removed using a rotary evaporator to obtain a copolymer resin composition (copolymer content: 45%).

The above copolymer resin composition was placed in the same apparatus as above, and then 28.4 g of glycidyl methacrylate was added.

0.2 mol) and hydroquinone (0.05 g) were reacted at 110 to 120°C for 3 hours, and the reaction rate of glycidyl methacrylate was 88%.

This resin liquid contains a side chain double bond type resin having a side chain represented by the above formula (m).

Flame-retardant monomer (a) A separable flask (1) equipped with a dropping funnel and a stirrer
dibrome neopentyl glycol 36 in
After 0 g (1.37 mol) was charged and melted at 110° C., 1 g 5 g (1.25 mol) of phthalic anhydride and 1.0 g of para-toluenesulfonic acid were added.

It was made to react at 170 degreeC under reduced pressure of 20-200 mm 1g for 4 hours. As a result, the acid value of the product was 40. Next, 140 g of styrene monomer, 54 g (0.38 mol) of glycidyl methacrylate, and 0.12 g of hydroquinone.
.

After adding 1.2 g of triethylamine, the mixture was reacted at 80'C for 4 hours. As a result, the reaction rate of glycidyl methacrylate was 95%, and a flame retardant monomer solution with an acid value of 9 was obtained.

Flame retardant monomer (b) In a separable flask (500 ml) equipped with a stirrer, dibrome neopentyl glycol (2F32 g).

1 mol), acrylic acid (108 g, 1.5 mol), 2.6 g of sulfuric acid and 0.05 g of rosebenzoquinone at 95°C.
The mixture was heated and stirred, and air was passed through the mixture at a rate of about 2 ONj2/hour. The water produced by the esterification was discharged with a stream of air, accompanied by a small amount of acrylic acid. After 6 hours, a water slurry containing 6 g of barium carbonate was added and the mixture was operated until no water was distilled out, to obtain an acrylic ester mixture of dibrome neopentyl glycol.

Flame retardant monomer (c) Separable flask equipped with a stirrer (looOml
) was charged with acrylic acid (72 g, 1 mol) and 3 g of BF3/ether catalyst, and while epichlorohydrin (463 g, 5 mol) was added dropwise from the dropping funnel, the reaction was carried out while maintaining the reaction temperature at 50° C. or lower.

The reaction was completed in 6 hours, so neutralize it with aqueous ammonia.
After separating the aqueous phase using a separator funnel, anhydrous sodium sulfate was added to dehydrate it.

Excess sodium sulfate and hydrated sodium sulfate were removed by filtration.

1 mm 1 g of 30°C liquid at a depth of 1 cm
The pressure was reduced by 1 inch to remove volatile components.

Various types of equipment can be used for the continuous pressure production of laminates in the present invention, examples of which include a double endless belt press, roto cure, multistage roll press, and caterpillar press. Here, the method using a double endless belt press will be described in detail. As shown in FIG. 5. The main parts are a double endless belt press device 7 having a pair of pressure rollers 6 and a group of 6, a release film or metal foil feeding device 8, a cutting device 9 for the laminate C, and a heat curing furnace IO.

Incidentally, as a modification of the pressurized continuous manufacturing method using these series of devices, a molding method using intermittent drawing of the base material and the laminate can also be applied.

The pressure A during curing by the double endless belt applied in the present invention is in the range of 0.01 kg/c to 10 kg/c, more preferably 0.1 kg/c to 5 kg.
/cd range. Here the pressure is O, 01kg/
If the pressure is lower than cd, the pressure will be insufficient, and the resin content of the laminate will become excessive, resulting in insufficient hot rigidity and, on the other hand, 10k
If a pressure higher than g/cd is used, the resin impregnated into the base material is discharged too much and delamination is likely to occur.

Pressure during curing ranges from 0.01kg/cd to 10kg/c♂
It exhibits suitable mechanical properties, especially when used as a printed circuit board for electric circuits, falling within the range of . The resin liquid containing the side chain double bond type resin used in the present invention as a main component exhibits non-Newtonian fluid behavior, and it is presumed that this makes it easy to control the resin ratio through appropriate pressure curing.

A double endless belt press was previously illustrated as an example of a pressurizing device during curing which is preferable for carrying out the method according to the present invention, but as another preferable structure of the double endless belt press, the belt waves in the vertical direction of the laminate B. A gradually advancing structure can be adopted in order to enhance the pressurizing effect of the base material impregnated with a resin liquid containing a side chain double bond type resin as a main component according to the present invention. As shown in Fig. 2, the belt of the pressurizing part advances in the heat curing furnace 12 through a group of direction changing rollers 11, 11, etc. arranged in a staggered manner, and the laminate B sandwiched between the belts moves in the vertical direction. It is presumed that this is because the straining effect increases at the part where the belt moves in waves and changes direction.

Example 1 Kraft paper of 1140g/nf
-305J (trade name, manufactured by Nippon Carbide Co., Ltd., methylolmelamine) in a 10% methanol solution, and then passed through a hot air dryer at 130° C. Five sheets of kraft paper were pretreated simultaneously and continuously. This will make the kraft paper 12.
5 parts by weight or more was applied.

Next, kraft paper was continuously impregnated with a resin solution prepared by adding 1.5 parts of tart-butyl peroxybenzoate as a curing catalyst to 100 parts of prepolymer 11 solution, and 5 sheets of the impregnated kraft paper were divided into two sheets. The resin liquid is introduced between squeezing rolls and squeezed out from above and below to form a laminate. A release polyester film is introduced into the upper and lower surfaces of this squeezing roll to cover the laminate. Subsequently, a double endless belt press having a pair of pressure rolls was used to
A laminated plate was continuously obtained by heating at 8 kg/cj at ℃.

After cutting this product, the resin solution was further cured at 140° C. for 1 hour to ensure complete curing to obtain a desired laminate.

Table I shows the characteristic values of the obtained laminate.

(The following is a blank space) Example 2 A laminate was obtained in the same manner as in Example 1, except that a group of five direction changing rollers with a diameter of 100 mm arranged in a staggered manner was used.

Table I shows the characteristic values of the obtained laminate.

Comparative example 1 Maximum pressure is 0.005 kg with double belt press device
The raw materials were arranged in the same manner as in Example 1, except that the weight ratio was ヰ%, and the hot elastic modulus at 100°C was 240k.
Except for g/a+Ii, the other characteristic values were almost the same as in the example. The heat resistance of this product in a 260° C. solder bath was insufficient, and it had the disadvantage of being susceptible to plastic deformation in the bath.

Comparative Example 2 The maximum pressure was 20 kg/(!
A laminate was manufactured using the same raw materials, equipment, and operating conditions as in Example 1, except for -.

The obtained laminate had partial delamination and was not practical.

[Effect] By using the resin liquid containing the side chain double bond type resin disclosed in the present invention, hot elasticity can be improved by continuous heating and pressure molding, and by using a special undulating pressure molding method. It has become possible to efficiently produce high-quality laminates.

Claims (2)

[Claims] (1) A method for continuous production of laminates, which comprises impregnating a plurality of elongated substrates with a curable resin liquid while continuously conveying them, then laminating them, curing the laminate, and cutting it. A method for continuously manufacturing a laminate, characterized in that a resin composition containing a side chain double bond type resin as a main component is used as a curable resin liquid and is cured under pressure. (2) The continuous production method of a laminate according to claim 1, wherein the laminate is pressed and cured while being waved in the upper and lower surface directions through a group of direction changing rollers arranged in a staggered manner.