JPS6136334A - Manufacture of laminated board - Google Patents

Abstract

PURPOSE:To manufacture a thermosetting resin laminated board having excellent flame-retardance and moisture resistance, by preparing a cocondensation resin from formaldehyde and an ester exchange reaction product of a phosphate or phosphite and a polyhydric phenol, and using the resin as a varnish for pretreatment. CONSTITUTION:The objective laminated board can be manufactured by (1) carrying out the cocondensation of (A) a reaction product obtained by the ester-exchange reaction of (i) 1-4mol of a phosphoric acid ester of formula I and/or a phosphorous acid ester of formula II (R1-6 are alkyl, aryl, preferably aryl) with (ii) preferably 1-3mol of a polyhydric phenol in the presence of anhydrous K2CO3, etc. as a catalyst, at >=100 deg.C with (B) 1-3mol of formaldehyde, based on 1mol of the compound having phenolic hydroxyl group, using trimethylamine, etc. as a catalyst, (2) using the obtained resin as the varnish for the pretreatment, and a thermosetting resin as the varnish for the post-treatment, and (3) laminating the substrates impregnated or coated with said varnishes.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a thermosetting resin laminate having excellent flame retardancy and moisture resistance.

(Prior Art) Conventionally, a method for making laminates flame retardant is to add inorganic compounds such as phosphorus compounds, bromine compounds, nitrogen compounds, and antimony to thermosetting resins, either alone or in combination. ing.

Phosphorous compounds have excellent flame retardancy, and when used in combination with bromine compounds, they exhibit particularly excellent flame retardant effects.

What is the flame retardancy of nitrogen compounds compared to phosphorus and bromine compounds? Moisture resistance is improved by impregnating the base material with pheol resin, melamine resin, and benzoguanamine resin, either alone or in combination, as a pre-treatment face. but,
Phenolic resin has no effect on flame retardancy. Melamine resins and benzoguanamine resins do not have sufficient flame retardancy, and their moisture resistance and electrical performance are inferior to phenolic resins.

When a phosphorus compound that has flame retardant properties is used alone,
It has no moisture resistance effect and has poor heat resistance.

Furthermore, even when used in combination with phenol resin, melamine resin, and benzoguanamine resin, heat resistance is significantly reduced because it is not incorporated into the resin system.

(Object of the Invention) The object of the present invention is to provide a method for producing a thermosetting resin M-layer plate having excellent flame retardancy and moisture resistance.

(Structure of the Invention) The present invention relates to phosphoric esters represented by the general formula (I) and/or the general formula (I
t) Show. ) is a reaction product A obtained by transesterification from the phosphites shown and polyhydric phenols.
and formaldehyde (B) as a pre-treatment phenol, which is impregnated and adhered to a base material in a predetermined amount, and further a thermosetting resin is used as a post-treatment phenol, and the base material that is impregnated and adhered to a predetermined amount is molded. That is.

Examples of the phosphoric acid esters represented by the general formula (I) include trimethyl phosphate, triethyl phosphite, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, trischloroethyl phosphate,
Trischloroel phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, xylenyl diphenyl phosphate, monophenyl diisozolphenyl phosphate , diphenylmonoisopropylphenyl phosphonate, and the like. At least one of these is used. R,, R2, Rs are alkyl groups, aryl
l) groups, which may be the same or different from each other. Aryl groups also include those in which hydrogen in the benzene ring is replaced with an alkyl group or a halogen.

Examples of the phosphites represented by the general formula (II) R5-0P(II) include triethyl phosphite, tri-n-butyl phosphite, and tris-2-
ethylhexyl phosphite tridecyl phosphite,
Examples include tristridecyl phosphite, tristearyl phosphite, diphenylmonodecyl phosphite, dienylmonotridecyl phosphite, triethyl phosphite, trisnonylphenyl phosphite, and the like. At least one of these is used. R4, Ra,
Rs is an alkyl group or an aryl group, and may be the same or different. Aryl groups also include those in which hydrogen in the benzene ring is substituted with an alkoxy group or a halogen. At least one of these phosphoric acid esters and phosphorous acid esters is used. Examples of polyhydric phenols include compounds represented by the general formula % (e.g. bisphenol A, bisphenol F1 bisphenol S, etc.), dimer of P-impropenylphenol, catechol, resorcinol, hydroquinone, pyrogallol, hydroxyhydroquinone, Phloroglucin, apionol, 1.2.3.5-tetrahydroxybenzene (including those in which hydrogen in the benzene ring is substituted with an alkyl group, etc.) are used.

The transesterification reaction between phosphoric esters and/or phosphoric esters and polyhydric phenols is carried out at a temperature of 100°C or higher, preferably 130 to 180°C. Some of them do not dissolve at temperatures below 100°C, and the reaction does not proceed easily. Alcohols and phenols produced by transesterification may be distilled out of the thread during or after the reaction, or may be left as they are. In particular, the by-produced phenols can also be used as raw materials for thermosetting resins.

The catalyst used for the transesterification reaction is anhydrous 2COs,
Examples include inorganic compounds such as CsF and anhydrous Na2COm, and organic base compounds such as triethylamine, diethylamine, and benzyldimethylamine.

It is preferable to use a catalyst amount of 0.001 to 2.0% (same as below weight%) based on the entire system.If the catalyst amount is less than 0.001%, the transesterification reaction will be difficult to proceed, and if the catalyst amount is less than 0.001%, the transesterification reaction will not proceed easily. In this case, especially when an inorganic compound is used, the electrical properties of the laminate are likely to deteriorate.

The blending molar ratio of phosphoric acid esters and/or phosphite esters and polyhydric phenols is 1 to 4 moles of phosphoric acid esters and phosphorous acid esters to 1 to 4 moles of polyhydric phenols.
5 mol is preferred.

Performing a transesterification reaction of phosphoric acid esters and/or phosphite esters and polyhydric phenols using a catalyst,
For example, a reaction product containing a compound represented by general formula (IV), etc. can be obtained.

Ra -0/CRt+ Rs represents an alkyl group or an aryl group. ) This reaction product preferably contains 10% or more of the total amount of compounds having at least one hydroxyl group of polyhydric phenols that have not reacted with the phosphoric acid esters and/or the phosphorous acid esters.

The reaction product (4) obtained by the transesterification reaction shown above is co-condensed with formaldehyde (Bl) to obtain a pretreated phenol. It is preferable to use 1 to 3 moles of formaldehyde per 1 mole of the compound.Formaldehydes (B) include paraformaldehyde, formaldehyde, trioxane, etc., and one or more of these is used. The catalyst used is organic amines such as trimethylamine, triethylamine, dimethylamine, diethylamine, monomethylamine, monoethylamine, ethylenediamine, ammoniahexamine, AJ(OH)s, Z
n(OH)3. One or more residual hydroxides such as NaOHMg(OH)2 are used. Preferably, organic amines are used. Further, other phenolic resins, melamine resins, benzoguanamine resins, etc. may be added to the pretreatment varnish as necessary.

Thermosetting resins used as post-processing phenols are general phenol resins, epoxy resins, polyester resins, melamine resins, etc., and these resins contain phosphoric acid esters, phosphorous acid esters, or tetrabromobisphenol A.
Alternatively, a bromine-based compound such as glycidyl ether may be used in combination (preferably. Here, post-treatment is a step of impregnating and adhering a predetermined amount of the above resin varnish to the pretreated substrate. The base materials used are paper, cloth, glass-mixed paper, synthetic #1! Kasuri cloth, etc.

In the above-mentioned structure, the reaction product (8) obtained by transesterification and formaldehyde (co-condensed with formaldehyde) are impregnated into the base material as a pre-treatment phenol, and the thermosetting resin is used as a post-treatment phenol. The required number of base materials impregnated with Kusunoki and adhered thereto are stacked one on top of the other, and the process is carried out at the required temperature (including room temperature) and the required pressure (including no pressure).

Example Cresyl diphenyl phosphate) 337 g1 110 g of catechol was placed in a reaction vessel, and 2C was added to anhydrous water as a catalyst.
Using 30.9 g of O, the reaction was continued at 125° C. for 9 hours to obtain a cresyl diphenyl phosphate-catechol reaction product. The phosphorus content was 6.6%. This reaction product and 80 g of 80% formaldehyde were mixed with 2.0 g of trimethylamine.
4 g was reacted at 80° C. for 9 hours to obtain a formaldehyde co-condensed resin, which was further soaked in methanol and ethanol to obtain a fabric for spinning treatment. This was impregnated into kraft paper with the above pretreated varnish and dried. The l1lJ treatment resin adhesion amount was 20%. To 100 parts of m-cresol resol resin modified with 24.5% tung oil, 15 parts of cresyl diphenyl phosphate and 25 parts of tetrabromobisphenol A glycidyl ether were added as a flame retardant, and used as a post-treatment varnish to completely adhere to the resin. The prepreg was impregnated and dried to a concentration of 50.8%, and five sheets of this prepreg were combined with adhesive-coated steel foil and laminated under heat and pressure to obtain a single-sided copper-clad laminate of 1.611111.

The characteristics of this copper-clad laminate are shown in the attached table.

Comparative example phenol resin 174g (phenol content 100g)
Add 337 g of Kresilschiff phosphate,
This was dissolved in methanol to prepare a pretreatment varnish.

This was impregnated into kraft paper with the above pretreated varnish and dried. The pretreatment resin adhesion amount was 20%. In addition, tung oil modification amount 24
゜For 100 parts of 5% m-cresol resol resin,
15 parts of cresylschiff ink nylphos 7-chlorite as a flame retardant;
Tetrabromobisphenol A glycidyl ether 25
As a post-treatment varnish, the total amount of resin deposited is 5α.
It was impregnated and dried to a concentration of 8%, and a copper-clad laminate was obtained in the same manner as in the examples below. The characteristics of this copper-clad laminate are shown in the attached table.

Comparative Example 2 Kraft paper was impregnated with a melamine resin varnish as a pretreatment varnish so that the amount of resin adhesion was 20%, and a copper-clad laminate was then obtained by the method shown in the example.

The characteristics of this copper-clad laminate are shown in the attached table.

(Effects of the Invention) As explained above, the present invention involves transesterification of phosphoric acid esters or phosphite esters with excellent flame retardancy and polyhydric phenols, and co-condensation of the resulting reaction product with formaldehyde. By impregnating a base material with a resin as a pre-treatment varnish and further using a thermosetting resin as a post-treatment varnish, a laminate having flame retardancy and excellent moisture resistance and heat resistance can be manufactured.

Claims (1)

[Claims] 1. General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(R_1, R_2,
R_3 represents an alkyl group or an aryl group. ), and/or general formula (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (R_4, R
_6 and R_6 represent an alkyl group or an aryl group. ) is the reaction product (
A method for producing a laminate, which comprises molding a base material in which a predetermined amount of a co-condensed resin of A) and formaldehyde (B) is impregnated into the base material as a pretreatment varnish. 2. R_ of phosphoric acid esters or phosphite esters
The method for producing a laminate according to claim 1, wherein 1 to R_6 are aryl groups.