JPH051139B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Background) The present invention relates to an epoxy laminate characterized by having excellent heat resistance and flame retardancy. (Prior art) Epoxy laminates have good mechanical strength, dimensional stability,
It is widely used as a structural material due to its excellent chemical resistance. In the electronics field, in addition to the above properties, they have good physical properties such as electrical insulation, moisture resistance, and dielectric properties, so they are often used as printed circuit boards. On the other hand, in the field of electrical products, the requirements for flame retardancy have recently become extremely strict, so it has become necessary to impart flame retardancy to epoxy laminates as well. In epoxy laminates, epoxy resins made from tetrabromobisphenol A or tetrachlorobisphenol A and epichlorohydrin can be used in combination with ordinary epi-bis type epoxy resins or novolac epoxy resins, or when used alone. Adds flammability. (Problems to be Solved by the Invention) However, when attempting to improve flame retardancy with epoxy laminates using epoxy resins made from tetrabromobisphenol A and tetrachlorobisphenol A, heat resistance, electrical properties On the other hand, when trying to maintain heat resistance and electrical properties, sufficient flame retardance cannot be obtained. As a result of intensive study, the inventors of the present invention
59-014859, and an epoxy resin made from tetrabromobisphenol A and tetrachlorobisphenol A, it has excellent heat resistance, electrical properties, and flame retardancy. The present inventors have discovered that an epoxy laminate having the following properties can be obtained, leading to the present invention. (Structure of the invention) That is, the present invention consists of the following: “(A) General formula () [However, ^R1 is an organic compound residue having l active hydrogens, n1, n2...nl are each 0 or an integer from 1 to 100, and the sum is from 1 to 100, l is an integer from 1 to 100 , A is an oxycyclohexane skeleton having a substituent, and is represented by the following formula, X is

[Formula]-CH= _CH2 and

[Formula] (R ² is H, alkyl group, carboalkyl group,
any one of the carboaryl groups), but at least 1 in the resin represented by the formula ()
Epoxy resin represented by 20 to 80 parts by weight (B) General formula () [X represents a bromine atom or a chlorine atom, n is 0
80 to 20 parts by weight (C) of a halogenated epoxy resin represented by [an integer greater than or equal to] 80 to 20 parts by weight (C) The base material is impregnated with a varnish prepared by blending a curing agent and, if necessary, a curing accelerator and an organic solvent. A flame-retardant laminate, characterized in that it is formed by laminating a plurality of evaporated and pre-cured prepregs and then curing them under heat and pressure. ”. Next, the present invention will be explained in detail. In the novel epoxy resin represented by the formula () of the present invention, R ¹ is an organic residue having active hydrogen, and examples of the precursor organic substance having active hydrogen include alcohols, phenols, carboxylic acids, amines, etc. and thiols. The alcohol may be a monohydric alcohol or a polyhydric alcohol. For example, methanol, ethanol, propanol, butanol, pentanol, hexanol,
Aliphatic alcohols such as octanol, aromatic alcohols such as benzyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, 1,3
Butanediol, 1,4 butanediol, pentanediol, 1,6 hexanediol, neopentyl glycol, oxybivalic acid neopentyl glycol ester, cyclohexanedimethanol, glycerin, diglycerin, polyglycerin, trimethylolpropane, trimethylolethane, penta Examples include polyhydric alcohols such as erythritol and dipentaerythritol. Phenols include phenol, cresol, catechol, pyrogallol, hydroquinone, hydroquinone monomethyl ether, hisphenol A, bisphenol F, 4,4'-dihydroxybenzophenone, bisphenol S, phenolic resin, cresol novolak resin, etc. . Carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, fatty acids from animal and vegetable oils, fumaric acid, maleic acid, adipic acid, dotecanoic acid, trimellitic acid, pyromellitic acid, polyacrylic acid, phthalic acid, isophthalic acid, terephthalic acid, etc. There is. Also included are compounds having both a hydroxyl group and a carboxylic acid, such as lactic acid, citric acid, and oxycaproic acid. Amines include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, cyclohexylamine,
Examples include octylamine, dotecylamine, 4,4'-diaminodiphenylmethane, isophoronediamine, toluenediamine, hexamethylenediamine, xylenediamine, diethylenetriamine, triethylenetetramine, and ethanolamine. Examples of thiols include mercapto compounds such as methyl mercaptan, ethyl mercaptan, propyl mercaptan, and phenyl mercaptan, mercaptopropionic acid or polyhydric alcohol esters of mercaptopropionic acid, such as ethylene glycol bis(methylmercaptopropionic acid) ester, and trimethylolpropane tris. (mercaptopropionic acid) ester, pentaerythol pentakis (mercaptopropionic acid) ester, and the like. In addition, as compounds having active hydrogen, polyvinyl alcohol, polyvinyl acetate partial hydrolyzate, starch, cellulose, cellulose acetate, cellulose acetate butyrate, hydroxyethyl cellulose, acrylic polyol resin, styrene allyl alcohol copolymer resin, styrene-malein Examples include acid copolymer resins, alkyd resins, polyester polyol resins, polyester carboxylic acid resins, polycaprolactone polyol resins, polypropylene polyols, and polytetramethylene glycols. Furthermore, the compound having active hydrogen may have an unsaturated double bond in its skeleton, and specific examples include allyl alcohol, acrylic acid, methacrylic acid, 3-cyclohexenemethanol, and tetrahydrophthalic acid. There is. The unsaturated double bonds of these compounds may further have an epoxidized structure. n1, n2...nl in general formula () are 0 or 1 to
100, but if it is over 100, the resin will have a high melting point and will be difficult to handle, making it practically unusable. l is an integer from 1 to 100. Among the substituents X of A in formula (),

Contains at least one [formula] Although it is essential

The more [formula] there are, the better. Delicious. especially

[Formula] is preferably as small as possible. That is, in the present invention, the substituent X is

[Formula] is the main one. Specifically, the novel epoxy resin represented by the formula () used in the present invention is a polyester obtained by ring-opening polymerization of 4-vinylcyclohexene-1-oxide using an organic compound having active hydrogen as an initiator. It can be produced by epoxidizing an ether resin, that is, a polycyclohexene oxide polymer having a vinyl group side chain, with an oxidizing agent such as a peracid. 4-Vinylcyclohexene-1-oxide is obtained by partially epoxidizing vinylcyclohexene obtained by a butadiene duplex reaction with peracetic acid. It is preferable to use a catalyst when polymerizing 4-vinylcyclohexene-1-oxide in the presence of active hydrogen. Catalysts include amines such as methylamine, ethylamine, propylamine, and piperazine; organic basic acids such as pyridines and imidazoles; organic acids such as formic acid, acetic acid, and propionic acid; inorganic acids such as sulfuric acid and hydrochloric acid; and sodium methylate. Alcoholates of alkali metals such as KOH, alkalis such as NaOH, Lewis acids such as BF ₃ , ZnCl ₂ , AlCl ₃ , SnCl ₄ or their complexes, organometallic compounds such as triethylaluminum, diethylzinc, etc. be able to. These catalysts can be used in an amount of 0.01 to 10%, preferably 0.1 to 5%, based on the reactants. Reaction temperature is -70~200℃, preferably -30℃
~100℃. The reaction can also be carried out using a catalyst. A solvent containing active hydrogen cannot be used. That is, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic solvents such as benzene, toluene, and xylene, as well as ethers, aliphatic hydrocarbons, esters, and the like can be used. Now, the polycyclohexene oxide polymer having a vinyl group side chain synthesized in this way is epoxidized, and the formula () used in the present invention is
To produce the new epoxy resin, either peracids or hydroperoxides can be used. As peracids, performic acid, peracetic acid, perbenzoic acid, trifluoroperacetic acid, etc. can be used. Among these, peracetic acid is a particularly preferred epoxidizing agent because it is industrially available at low cost and has high stability. Hydroperoxides include hydrogen peroxide, tertiary butyl hydroperoxide,
Cumene peroxide etc. can be used. A catalyst can be used during epoxidation if necessary. For example, in the case of a peracid, an alkali such as soda carbonate or an acid such as sulfuric acid may be used as a catalyst. In addition, in the case of hydroperoxides, the catalytic effect can be obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, an organic acid with hydrogen peroxide, or molybutene hexacarbonyl with tertiary butyl hydroperoxide. . The epoxidation reaction is carried out by adjusting the presence or absence of a solvent and the reaction temperature depending on the equipment and physical properties of the raw materials. Depending on the epoxidation reaction conditions, olefin bonds can be epoxidized simultaneously with substituents in the raw materials.

[Formula] and generated substituents

As a result of a side reaction between [Formula] and an epoxidizing agent, a modified substituent is generated and included in the target compound. Substituent in target compound

[Formula] Substituent

[Formula] and the ratio of the three modified substituents are determined by the type of epoxidizing agent, the molar ratio of the epoxidizing agent to the olefin bond, and the reaction conditions. For example, when the epoxidizing agent is peracetic acid, the modified substituent mainly has the structure shown below, and is generated from the generated epoxy group and by-produced acetic acid. The target compound can be taken out from the reaction crude solution by ordinary chemical industrial means such as concentration. The epoxy resin represented by the formula () in the present invention is a commercially available epoxy resin produced from tetrabromobisphenol A or tetrachlorobisphenol A and epichlorohydrin. As the curing agent used in the present invention, curing agents used in known epoxy resins can be used, including amines, polyamide resins, acid anhydrides, polymercaptan resins, novolac resins, dicyandiamide,
This includes amine complexes of boron trifluoride. Particularly preferred are dicyanamide and acid anhydride. Acid anhydrides include the following: phthalic anhydride,
trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride,
Acid anhydrides such as methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, succinic anhydride, dothecenylsuccinic anhydride, succinic anhydride, and mixtures of the above acid anhydrides. In the present invention, the epoxy resin represented by general formula (1) can be used in combination with other epoxy resins as long as the properties thereof are not impaired. Here, the other epoxy resin may be any commonly used epoxy resin, such as Epibis type epoxy,
These include bisphenol F epoxy, novolak epoxy, alicyclic epoxy, and the like. In the present invention, the epoxy resin represented by formula (1)
20 to 80 parts by weight () Epoxy resin 80 represented by the formula
They are used by mixing at a ratio of ~20 parts by weight. If the epoxy of formula (1) is less than 20 parts by weight, sufficient heat resistance and electrical properties cannot be obtained, and if the epoxy of formula () is less than 20 parts by weight, sufficient flame retardance cannot be obtained. The laminate of the present invention is based on a varnish made by blending epoxy resins of formulas () and () in the above composition, and further containing an appropriate amount of a curing agent, a curing accelerator, and an organic solvent as necessary. A plurality of prepregs obtained by impregnating with water, evaporating the organic solvent, and pre-curing are laminated, and then heated and cured under pressure to form a mold. As the sheet-like substrate, any material used for forming ordinary laminates may be used, but for example,
Examples include glass cloth, non-woven ceramic fiber cloth, and non-woven fabric. (Effect of the invention) The laminate obtained as described above takes advantage of the properties of the epoxy resin represented by the formula (), so it has excellent heat resistance and electrical properties, and is also provided with flame retardancy. has been done. Therefore, it is useful as a copper-clad laminate for electrolysis. The present invention will be explained below with reference to Examples. Synthesis example 1 Allyl alcohol 58g (1 mol), 4-vinylcyclohexene-1-oxide 868g (7 mol)
and 4.7 g of BF ₃ etherate were mixed at 60° C. and reacted until the conversion of 4-vinylcyclohexene-1-oxide reached 98% or more as determined by gas chromatography analysis. Ethyl acetate was added to the obtained reaction crude liquid and washed with water, and then the ethyl acetate layer was concentrated to obtain a viscous liquid. In the infrared absorption spectrum of the product, the absorption by epoxy groups at 810 and 850 cm ^-1 observed in the raw material disappeared, and the presence of absorption due to ether bonds at 1080 and 1150 cm ^-1 , gas chromatography analysis showed that Allyl alcohol in the product is a trace amount, but in the infrared absorption spectrum it is 3450cm
It was confirmed that this compound has the structure shown by the following formula from the absorption of OH group at ^-1 . Further, 573 g of this compound was reacted with 387 g of peracetic acid in the same manner as in Synthesis Example 1 to obtain a viscous and transparent liquid. This compound has an oxirane oxygen content of 90.3%
In the infrared absorption spectrum, characteristic absorption due to epoxy groups was observed at 1260 cm ^-1 . Furthermore, 1640cm ^-1
Absorption due to residual vinyl groups is observed in 3450
OH group at cm ^-1 , 1730 cm ^-1

[Formula] This compound has a structure of the general formula () (R ₁ :trimethylolpropane residue l=3,
It was confirmed that n ₁ , n ₂ , n ₃ =5 on average, including one part of a group in which acetic acid was added to an epoxy group). Examples 1 to 4, Comparative Examples 1 to 3 In order to demonstrate that the cured epoxy resin used in the laminate of the present invention has excellent heat resistance and electrical properties, the epoxy resin and the curing agent were melt-mixed, pulverized, and then pressed. It was molded and its physical properties were compared. The results are shown in Table-1.

【table】

[Table] Examples 5 to 6 The resin compositions shown in Examples 1 to 4 were made into a 50% solution of methyl ethyl ketone, and a glass cloth was impregnated to obtain a prepreg with a resin content of 43%. Five sheets of prepreg were stacked and hot pressed to obtain an epoxy laminate. The resulting laminate was subjected to a heat resistance test based on JIS-C6468. The results are shown in Table-2.

【table】

Claims (1)

[Claims] 1 (A) General formula () [However, R ¹ is an organic compound residue having l active hydrogens, n1, n2...nl are each 0 or 1
An integer of ~100, the sum of which is 1 to 100, l represents an integer of 1 to 100, A is an oxycyclohexane skeleton having a substituent, and is represented by the following formula, X is [Formula] -CH=CH ₂ and [Formula] (R ² is H, alkyl group, carboalkyl group,
any one of the carboaryl groups), but at least 1 in the resin represented by the formula ()
Epoxy resin represented by 20 to 80 parts by weight (B) General formula () [X represents a bromine atom or a chlorine atom, n is 0
80 to 20 parts by weight (C) of a halogenated epoxy resin represented by [an integer greater than or equal to] 80 to 20 parts by weight (C) A base material is impregnated with a varnish prepared by blending a curing agent and, if necessary, a curing accelerator and an organic solvent. A flame-retardant laminate, characterized in that it is formed by laminating a plurality of evaporated and pre-cured prepregs and then curing them under heat and pressure.