JPH07110902B2 - Method for manufacturing prepreg for heat-resistant laminated plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a method for producing a prepreg for a heat-resistant laminated sheet, which is excellent in heat resistance, moisture resistance and storage stability.

(Prior Art) In recent years, electronic devices have been remarkably developed, copper-clad laminates have been widely used, and excellent properties are required. In particular, there is a demand for a copper clad laminate having good workability, such as a multilayered wiring board, a through hole having a smaller diameter, and less smear during drilling as wiring density increases. On the other hand, with the demand for improved productivity and cost reduction, increasingly severe processing conditions such as hot air levelers and reflow soldering are being added in the wiring board mounting process. Among these, the heat resistance and moisture resistance of the copper clad laminate, which is the substrate, have been required to be more excellent than ever. In order to meet these requirements, in recent years, an addition reaction type polyimide resin has been used in place of an epoxy resin which is widely used for copper clad laminates. When this polyimide resin is used in a prepreg for a copper clad laminate, the occurrence of smear during drilling becomes almost zero, and the heat resistance in the working process and long-term test is significantly improved.

However, conventionally used addition reaction type polyimide resins have various problems as described below.

The reaction product of N, N′-bisimide of unsaturated dicarboxylic acid and diaminodiphenylmethane is excellent for laminates, but diaminogenylmethane is highly reactive and can be used for varnishes and prepregs. There is a problem that the usage time is short. Unsaturated dicarboxylic acid N, N'-bisimide and those having aminophenol as a reaction component, shows a well-balanced property for laminates and is excellent in processability, but has a difficulty in moisture resistance, for example, For long-term storage of the obtained prepreg and laminate, special attention must be paid to moisture absorption. In addition, unsaturated dicarboxylic acid N, N '
-The one obtained by reacting bisimide with aminobenzoic acid is
Although it is suitable for laminates, it has poor solubility in low boiling point solvents and has difficulty in coating glass cloth etc. during the production of prepregs. Furthermore, care must be taken when storing the resin solution. There was a problem.

(Problems to be Solved by the Invention) The present invention has been made to solve the above-mentioned problems, and has heat resistance, moisture resistance, storage stability of a resin solution or prepreg, and solubility in a low boiling point solvent. It is intended to provide an excellent method for producing a prepreg for a heat-resistant laminated plate, which is less likely to cause smear.

[Structure of the Invention] (Means for Solving Problems) The method for producing a prepreg for a heat-resistant laminated plate of the present invention comprises (A) a general formula (In the formula, R ¹ is 2 having at least 2 carbon atoms.
A divalent group, R ² represents a divalent group containing a double bond between carbon atoms), an N, N′-bisimide compound of an unsaturated dicarboxylic acid represented by the formula (B) (Wherein R ³ represents a hydrogen atom, a halogen atom or an alkyl group), (C) a general formula (Wherein X ¹ , X ² , X ³ , and X ⁴ represent the same or different halogen atoms) and a resin composition containing an addition reaction product consisting of an aromatic diamine as an essential component is applied to a substrate. It is characterized by being dried after impregnation. The addition reaction product is the total amount [(B) + (C)] of the aminophenol of (B) and the aromatic diamine of (C) with respect to 1 mol of the N, N′-bisimide compound of (A).
0.1 to 1.0 mol is added.

The present invention will be described below.

First, the N, N'-bisimide compound (A), the aminophenol (B) and the aromatic diamine (C) are reacted to obtain an addition reaction product, and then a resin composition is obtained using this as an essential component. As the N, N'-bisimide compound of the unsaturated dicarboxylic acid (A), those having the following general formula are used.

However, in the formula, R ¹ represents a divalent group having at least 2 carbon atoms, and R ² represents a divalent group containing a double bond between carbon atoms. That is, R ¹ is a linear or branched alkylene group, a cycloalkylene group having a ring of 5 to 6 carbon atoms, a heterocyclic group containing at least one of oxygen, nitrogen or sulfur atom, benzene. Group or polycyclic aromatic group, as well as a plurality of benzene groups and alicyclic groups bonded by —NHCO—, —NR ⁴ —, —SiR ⁴ R ⁵ — or —SO ₂ — and the like. it can. However, R ⁴ and R ⁵ represent an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having a ring having 5 to 6 carbon atoms, and a benzene group.

Examples of R ² , that is, a divalent group containing a double bond between carbon atoms include a maleic acid residue, a citraconic acid residue, and a tetrahydrophthalic acid residue.

Therefore, specific examples of the N, N′-bisimide compound of unsaturated dicarboxylic acid satisfying the above-mentioned conditions of R ¹ and R ² include the following, and each of them is one kind or two or more kinds. It can be used in a mixed system. Maleic acid N,
N'-4,4'-diphenylmethane bisimide, maleic acid
N, N'-4,4'-diphenyl ether bisimide, maleic acid N, N'-paraphenylene bisimide, maleic acid N,
N'-benzidine bisimide, maleic acid N, N'-methaxylene bisimide, maleic acid N, N'-1,5-naphthalene-bisimide, maleic acid N, N'-4,4'-diphenylsulfone-bisimide , Maleic acid N, N'-2,2'-4,4 '
-Dimethylene-cyclohexane-bisimide, maleic acid N, N'-4,4'-dicyclohexyl-methanebisimide, maleic acid N, N'-4,4'-diphenylcyclohexane-bisimide, maleic acid N, N'-4 , 4'-diphenyl-phenylamine-bisimide, maleic acid N, N'-4,
4'-diphenyl-diphenylsilane-bisimide, maleic acid N, N'-4,4'-diphenylsulfur-bisimide,
Maleic acid N, N'-2,2 '-(4,4'-diphenyl) -propane-bisimide, maleic acid N, N'-metaphenylene-bisimide, maleic acid N, N'-3,3'-( N, N′−
Metaphenylene-bisbenzamide) bisimide and the like.

As the (B) aminophenol used in the present invention, those having the following general formula are used.

However, in the formula, R ³ represents a hydrogen atom, a halogen atom or an alkyl group. The following compounds are mentioned as these concrete compounds, These are individual or are used in mixture of 2 or more types. o-aminophenol, m-aminophenol, p
-Aminophenol, 2-amino-4-chlorophenol, 2-amino-4-methylphenol and the like.

As the (C) aromatic diamine used in the present invention, an aromatic diamine having the following general formula is used.

However, in the formula, X ¹ , X ² , X ³ , and X ⁴ represent the same or different halogen atoms, and specific compounds include, for example, 4,
4'-diamino-3,3 ', 5,5'-tetrachlorodiphenylmethane, 4,4'-diamino-3,3', 5,5 'tetrabromodiphenylmethane, and the like, which may be used alone or in combination of two or more. Use by mixing.

The above-mentioned N, N'-bisimide compound of unsaturated dicarboxylic acid (A), aminophenol (B) and aromatic diamine (C) are heated and reacted in a solvent-free or inert solvent to produce an addition reaction product. The mixing ratio of these three components is such that the total amount of the aminophenol and the aromatic diamine is 0 to 1 mol of the N, N'-bisimide compound of the unsaturated dicarboxylic acid.
It is desirable to add 1 to 1.0 mol. If the proportion is less than 0.1 mol, the reaction does not proceed and the heat resistance, toughness and other properties deteriorate, and if it exceeds 1.0 mol, unreacted amine remains,
It is not preferable because the heat resistance is significantly lowered. The mixing order of the three components, the reaction temperature, and the solvent can be appropriately selected and are not particularly limited.

Hereinafter, a typical manufacturing process will be described as an example.

N, N'-bisimide compound of unsaturated dicarboxylic acid in the reaction vessel, aminophenol and aromatic diamine are charged in a predetermined ratio, heated to 100 ~ 200 ℃ to melt the contents,
Allow the reaction to proceed until the viscosity and cure time are reached. The reaction product can be dissolved in a solvent such as acetone, methyl ethyl ketone, dioxane, tetrahydrofuran, dimethylformamide (DMF) to prepare a resin solution having suitable properties for a laminate. It is also possible to use a solvent from the beginning. For example, in a reaction vessel, N, N'-bisimide compound of unsaturated dicarboxylic acid, aminophenol and aromatic diamine are charged together with dioxane, a predetermined viscosity while refluxing dioxane, to react until cure time, then DMF etc. A resin solution for a laminated board can be produced by adding the solvent and cooling.

The addition reaction product thus prepared can be blended with various additives and fillers to form a resin composition depending on the application. For example, a catalyst such as imidazole may be added to adjust the curing rate, and a coupling agent may be added to impart adhesiveness. Further, a flame retardant and an inorganic filler may be appropriately added in order to impart flame retardancy.

The resin composition produced as described above, glass cloth, 100 in a drying tower after coating and impregnating a substrate such as glass nonwoven fabric
A prepreg for heat-resistant laminate can be manufactured by drying within a temperature range of up to 200 ° C.

This prepreg is heated and pressed by a predetermined method and can be used for producing a laminate, a copper clad laminate or a printed wiring board.

(Function) By using the specific diamine having the above-mentioned potential as the aromatic diamine, the pot life of the varnish or the prepreg is improved, and the solubility is improved even in the low boiling point solvent. Further, it becomes possible to manufacture a prepreg excellent in heat resistance while maintaining excellent workability peculiar to the addition reaction type.

(Example) Next, the present invention will be specifically described with reference to examples.

Example 1 In a flask equipped with a stirrer and a thermometer, maleic acid N,
N'-4,4'-diphenylmethanebisimide 358 g and 2-amino-4-chlorophenol 45 g and 4,4'-diamino-3,
Charge 25 g of 3 ', 5,5'-tetrachlorodiphenylmethane and heat with stirring. When it exceeds 100 ℃, it gradually begins to dissolve and becomes a brown liquid. This solution was heated to 120 ° C. and stirred for 1 hour. Thus, the aminophenol and the aromatic diamine were completely added to the bismaleimide, and then dissolved in dioxane and DMF to obtain a 50% solution, which was stirred to form a uniform varnish. Next, a woven fabric having a thickness of 180 μm was coated and impregnated with the prepared varnish and dried at a temperature of 160 ° C. to produce a prepreg having a resin content of 43% by weight. 170 ° C with 4 sheets of this prepreg and 2 sheets of 70μm thick copper foil
At a temperature of 40 kg / cm ² for 90 minutes, and integrally molded under pressure to form a copper clad laminate having a thickness of 0.9 mm. After forming an inner layer circuit on this copper-clad laminate, two prepregs were superposed on each of the front and back sides, and a copper foil having a thickness of 18 μm was superposed on each of the upper and lower surfaces to form a four-layer board. The various properties of the obtained four-layer board were tested. The results are shown in Table 1. The heat resistance and moisture resistance were excellent, and the effect of the present invention was confirmed. The pot life of the prepreg was evaluated during storage. As shown in Table 1, it was found that the prepreg had good storage stability.

Example 2 Maleic acid N, N'-4,4'-diphenylmethanebisimide
358 g and o-aminophenol 16 g and 4,4'diamino-3,
A varnish was produced in the same manner as in Example 1 except that 55 g of 3 ', 5,5'-tetrachlorodiphenylmethane was charged into the flask. Using this varnish, a prepreg and a four-layer board were prepared under the same conditions as in Example 1. Further, various properties were tested in the same manner, and the results are shown in Table 1. The heat resistance and moisture resistance were excellent, and the effect of the present invention was confirmed. The pot life of the prepreg was evaluated during storage, and it was found that the storage stability was good as shown in Table 1.

Example 3 Maleic acid N, N′-4,4′-diphenylmethanebisimide
358 g and m-aminophenol 45 g and 4,4'-diamino-3,
A varnish was produced in the same manner as in Example 1 except that 30 g of 3 ', 5,5' tetrachlorodiphenylmethane was charged into the flask. Using this varnish, a prepreg and a four-layer board were made under the same conditions as in Example 1. Further, various properties were tested in the same manner, and the results are shown in Table 1. The heat resistance and moisture resistance were excellent, and the effect of the present invention was confirmed. The pot life of the prepreg was evaluated during storage, and it was found that the storage stability was good as shown in Table 1.

Comparative Example 1 Maleic acid N, N'-4,4'-diphenylmethanebisimide
358 g, m-aminophenol 45 g and p-aminobenzoic acid ethyl ester 41 g were charged into a flask, and a varnish was produced in the same manner as in Example 1. Using this varnish, a prepreg and a four-layer board were prepared under the same conditions as in Example 1. Further, various characteristics were tested in the same manner, and the results are shown in Table 1.

Comparative Example 2 Maleic acid N, N'-4,4'-diphenylmethanebisimide
A varnish was produced in the same manner as in Example 1 except that 358 g, m-aminophenol 33 g and 4,4'-diaminodiphenylmethane 35 g were charged into a flask. Example 1 using this varnish
A prepreg and a four-layer board were made under the same conditions as above.
In addition, various characteristics were tested in the same manner.
Shown in the table.

[Effects of the Invention] As is clear from the above description and Table 1, according to the method for producing a prepreg for a heat-resistant laminated plate of the present invention, heat resistance, moisture resistance, storage stability of a resin solution or prepreg, and low A prepreg having excellent solubility in a boiling solvent and less generation of smear can be obtained.

Claims (2)

[Claims] 1. (A) General formula (In the formula, R ¹ is 2 having at least 2 carbon atoms.
A divalent group, R ² represents a divalent group containing a double bond between carbon atoms), an N, N′-bisimide compound of an unsaturated dicarboxylic acid represented by the formula (B) (Wherein R ³ represents a hydrogen atom, a halogen atom or an alkyl group), (C) a general formula (Wherein X ¹ , X ² , X ³ , and X ⁴ represent the same or different halogen atoms), a resin composition containing an addition reaction product as an essential component consisting of A method for producing a prepreg for a heat-resistant laminated plate, which comprises drying after coating and impregnation. 2. The total amount of the addition reaction product of aminophenol (B) and aromatic diamine (C) [(B) + (with respect to 1 mol of N, N'-bisimide compound of (A)]. C)]
The method for producing a prepreg for a heat-resistant laminated plate according to claim 1, wherein 0.1 to 1.0 mol is added.