JPS58197604A - Composite sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite sheet used as an electrical insulating material for one-rotation machines, power transformers, or flexible printed circuit boards. To provide a composite sheet having good properties and flexibility.

In general, aromatic polyamide paper is widely used as an electrical insulating material used for slot insulation of single-turn machines, interlayer insulation of power transformers, and correlation insulation of power transformers, considering its heat resistance and four-gas characteristics. In addition, aromatic polyamide paper has excellent flexibility and is cheaper than polyimide film, so it is laminated with steel foil.

It is also used as a substrate for flexible printed circuit boards. However, it had the disadvantage of high hygroscopicity and, as a result, poor dimensional stability. In order to improve these drawbacks, a method of coating or impregnating with resin can be considered, but
In order to maintain the heat resistance of aromatic polyamide paper (heat resistance grade H class -180°C or lower), a resin with high heat resistance must be used in combination, which naturally limits the resins that can be used. Examples of these resins include:

Examples include thermosetting alicyclic epoxy 11M resin and thermosetting 711 resin, but when the resin is applied or impregnated and then thermally cured, the sheet generally becomes hard and a certain degree of aT flexibility is required. It was unsuitable for such applications.

It is a resin that has both heat resistance and flexibility.

Thermoplastic polyimide resin or polyamideimide resin is suitable, but the solvent used to dissolve these resins is mainly N-methyl-2-pyrrolidone, dimethylformamide, etc. However, since these solvents also dissolve the aromatic polyamide paper that is the base material, it is impossible to impregnate the coating material. The present inventor, Hiromu, solved the above problem by using a polyamideimide resin soluble in a cresol solvent.

The present invention relates to a composite sheet obtained by impregnating an aromatic polyamide paper with a polyamide-imide resin composition using a cresol solvent and then heating and drying the paper.

This composite sheet has no evidence that the base material has been exposed to solvent, and has excellent moisture resistance and heat resistance.

This composite sheet is used for slot insulation, interlayer insulation of zero-rotation machines, or correlation insulation of solder source transformers.It has heat resistance of class H, and is significantly superior to aromatic polyamide paper in terms of moisture resistance and dimensional stability. Are better. Furthermore, this material has sufficient flexibility after heating and drying, and can be used as a printed circuit board for l1iT by bonding it with copper foil.

The polyamide-imide resin composition using a cresol solvent used in the present invention is as follows.

Example High isocyanurate ring-containing polyisocyanate, diisocyanate, lactam, tricarboxylic anhydride, general X' other than tricarboxylic anhydride Formula X-R-4-Y)n, [X, X' are the same but 4 different The carboxyl radical may be an anhydride group, Y is a carboxyl group, an acid anhydride, a hydroxyl group or an amino group, and R is +h] 100 Z-+R-.

Aromatic, aliphatic, alicyclic or heterocyclic residues.

However, R1 and R may be the same or different.

Aromatic, 111 aliphatic, alicyclic or heterocyclic residues.

Z is -C)b, -CO, SOm- or -Q-,m
and I are integers of 1 or 2, and n・° is 4Ia less than or equal to l.
is the isocyanurate ring-containing polyisocyanate in an amount of 0 to 30 of the total isocyanate equivalent.
A polyamide-imide resin face obtained by reacting a compound represented by the general formula X-几→Y)n, other than tricarboxylic acid anhydride, in a cresol-based solvent at an equivalent percentage of θ to 30 equivalents of the total carboxyl equivalent is used. be done.

0 as incyanurate ring-containing polyisocyanate
For example, tolylene diisocyanate.

Aromatic diisocyanates such as xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate, naphthylene-15-diisocyanate, 4,4'-diphenylmethane diisocyanate, ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1
．． 6-hexamethylenecyisocyanate), l,12-dodecanediinocyanate, aliphatic diisocyanate,
Siteclob t'71.3-diisocyanate, cyclohexane 1.3-j? and 1,4-diisocyanate.

Ring diisocyanates such as isophorone diisocyanate. Triphenylmethane-4,4: An isocyanurate ring-containing polyisocyanate obtained by trimerization reaction of polyisocyanate such as 4"-triisocyanate is used. Considering heat resistance, tolylene diisonane is preferably used. It is preferable to use an incyanurate ring-containing polyisocyanate obtained by a trimerization reaction of an aromatic diisocyanate such as , 4,4'-diphenylmethane diisocyanate, or a trimerization reaction of isophorone diisocyanate.

A suitable method for producing isocyanurate ring-containing polyisocyanates is shown in Japanese Patent Application No. 148820/1982.

As the diisocyanate, aromatic diisocyanate, aliphatic diisocyanate or 8i used as a raw material for the queen incyanurate ring-containing polyinsyanate is used.
Group 11 diisocyanates are used. In consideration of heat resistance and the like, aromatic diisocyanates such as tolylene diisocyanate and 4,4'-diphenylmethane diisocyanate are preferred.

Isocyanurate ring-containing polyisocyanates are used as branching components, and the -t incyanurate ring core provides excellent heat resistance.

Isocyanurate ring-containing polyisocyanate has a total iso7
7 nate equivalent θ ~ 30 equivalent 1 percent #! used in enclosures. If it exceeds 30/1%, the degree of branching will increase, and gelation may occur in the fractions until the desired molecular number is reached.

The lactam, which is an important raw material for solubilization in cresol solvents, can generally be anything as long as it reacts with isocyanate or acid anhydride groups and is soluble primarily in cresol solvents.

T? ! Considering scale 1 reactivity and cost rYU, ε-
Caprolactam is preferred. The amount of lactam used is not particularly limited, but in consideration of heat resistance and the like, it is preferably less than 1% based on 100 equivalents of the total inocyanate equivalents.

Tricarboxylic anhydride includes trimellitic anhydride,
Butane-1,2,4-)licarboxylic anhydride and the like are used. In consideration of heat resistance and the like, trimellitic anhydride is preferred.

General formula other than tricarboxylic acid anhydride X-R-+Y)n
- The compound represented by □ has at least two carboxyl groups or acid anhydride groups that form an amide bond and/or imide bond with a polyisocyanate to form a tree, and further has a hydroxyl group or an amino group as necessary. It is something that has both. Considering the flexibility, heat resistance, abrasion resistance, etc., trimesic acid, tris(2-carboxyethyl)isonurate, 3,3. '4.4'-benzophe, nontetracarboxylic dianhydride, etc. are preferred, and the above-mentioned incyanurate ring-containing polyinocyanates such as tolylene diisocyanate trimer, isophorone diisocyanate trimer, etc. and trimellitic anhydride are preferred. The reaction product 1 with eg polyimide polycarboxylic acid is used.

X' General formula other than tricarboxylic anhydride X-R-(-Y)
,.

The compound represented by is used in an amount of 0 to 30 equivalent percent of the total carboxyl equivalents.

When the percentage exceeds 30, the degree of branching increases.

Gelation may occur during synthesis until the desired molecular weight is reached. Here, 1 equivalent of acid anhydride group, hydroxyl group, and amine/group of the acid component is treated as 1 equivalent of carboxyl group.

From the viewpoint of heat resistance and O7 flexibility, the amounts of the isocyanate component and the isocyanate component to be used are such that the equivalent ratio of the isocyanate group to the carboxyl group is preferably 1.5 to 0.7, more preferably 0.85 to 1. .15 range.

In the reaction, all the raw materials may be charged at the same time, or one reaction may be carried out in stages depending on the purpose. The reaction temperature is such that the main reaction is carried out at 200 to 220°C after all the components have been charged. The progress of the reaction can be determined by observing the generated carbon dioxide gas bubbles and the viscosity of the solution.

,・□“ In addition to cresol, phenol,
Xylenol etc. can be used, and a mixed solvent may also be used. Some of the synthesis solvents include 4 Aromatic organic solvents with high boiling points 1 For example, xylene, Nl58EKIHI80L-100,150 (trademark for aromatic hydrocarbons manufactured by Nippon Oil & Chemicals Co., Ltd.), cellosolve acetate (ethylene glycol 7, manufactured by Dow Chemical Company), Ethyl ether heptanoacetate (trademark) etc. can also be used.

The thus obtained polyamide-imide resin composition is preferably used with a resin content of 5 to 40 weight percent in the above-mentioned cresol solvent. In this case, xylene, Nl88
EKIHI80L-100, cellosolve acetate,
A chlorinated solvent such as trichlene may be used in combination.

In the present invention, the boria batimide tree soluble in cresol type II medium has at least a lactam as a starting material,
When diisocyanates and tricarboxylic anhydrides are used, substantially linear polymer structures are provided. The manufacturing method for such polyamide-imide trees is disclosed in Japanese Patent Publication No. 1973-2973.
This method is disclosed in Japanese Patent Application Laid-open No. 116591/1983, and the like.

When an incyanurate ring-containing polyinocyanate is used as a starting material in addition to at least a lactam, a diisocyanate and a tricarboxylic anhydride, a branched polymer is obtained. The manufacturing method of such branched polyamide-imide resin is disclosed in 4I' Application No. 148820/1983 and Japanese Patent Application No. 1983-148820.
No. 118596 1% Kensho 54-171473.

This is shown in the specification of US Pat. No. 3,238,181, etc.

At least the present lactam, diisocyanate and tricarboxylic anhydride are mixed as starting materials [1c and λ3. When a ketopolycarboxylic acid anhydride such as 4.4'-benzophene and nontetracarboxylic dianhydride is used, a 9-branched molecular polymer is obtained. A method for producing such branched polyamide-imide resin is disclosed in Japanese Patent Application No. 55-3048.
It is shown in No. 2.

Also, at least this lactam as a starting material.

In addition to diisocyanates and tricarboxylic acid anhydrides, trifunctional polycarboxylic acids 1 are added as branching components.
For example, it is known that when trimesic acid, tris(2-carboxyethyl)ine 7-anurate or the reaction product of isocyanurate ring-containing polyisocyanate and trimellitic anhydride is used, a zero-branched polymer can be obtained. There is. Taking into consideration the ease of handling, heat resistance, abrasion resistance, cost, etc., at least lactam, diisocyanate, tolylbonic acid anhydride, and incyanure are used as starting materials.
) 0 Tl in the cresol solvent obtained using the polyinsyanate containing 4! An il branched polyamideimide resin is preferred.

An epoxy resin is used in the polyamide-imide resin composition using a cresol solvent used in the present invention.

Alkoxy-modified melamine resin, 'Fe,/-formaldehyde resin, xylene formaldehyde resin, isocyanurate ring-containing polyisocyanate, organic acid metal salt,
polyether resin, polyamide resin, polyimide resin,
Polyhydantoin resin, polysulfo/acid resin, charcoal guanidine.

Benzotriazole, furan resin, phenoxy resin,
Modification can be performed by using additives such as urethane elastomer, polybutadiene rubber, nitrile butadiene rubber, and acrylic rubber in a proportion of 0.1 to 25 weight percent based on the resin content. Sometimes thermosetting resins, especially epoxy resins, are used to speed up the curing speed and improve smearability.

Alkoxy-modified melami/resin, phenol formaldehyde resin [1 thermosetting resin is preferred.

There is no limit to the percentage of aromatic polyamide paper used as the base material, and calendered vapor or untreated paper with a thickness ranging from 0.010 to 0.075 mm can be used.1 For example, Nomex (manufactured by Dubo Co., Ltd.) is used. In either case, since the coating contains several percent water, it is desirable to remove the water by heat treatment at a temperature of 100°C or higher just before coating or impregnation. The above-mentioned polyamide-imide resin composition is applied or impregnated onto the aromatic polyamide paper by dip coating.

Layers are applied using a roll coater method or the like. Heat drying.

10-60 minutes at 100-180℃, then 200-30 minutes
It is preferable to carry out drying at 0°C for 5 to 90 minutes.

The present invention will be described in detail.

Example 1 (1) Synthesis of polyamide-imide resin soluble in cresol solvents +11 Synthesis of inocyanurate ring-containing polyinocyanate Tolylene diinocyanate 600 Xylene 600 2-dimethylami,/etha, nor (catalyst) 1.8 Above components was placed in a fourth flask equipped with a temperature needle and a stirrer, and heated to 140°C in a stream of bare air.At the same temperature, the incyanate group content 1 (initial: 48%) decreased to 25tm%. The reaction proceeded until it was completed. The infrared spectrum of this substance is 1.710 cm-”.

Absorption of isocyanurate rings was observed at 1,410 cHl-1, and absorption of isocyanate groups was observed at 2,260 cIfM.

(ill Synthesis of polyamideimide resin soluble in cresol solvents Trimellitic anhydride 96.0 1.001-
Caprolactam 36.6 0.65 Cresol 300 The above ingredients except trimellitic anhydride were placed in a four-lobe flask equipped with a temperature needle and a stirrer.9 The temperature was raised to 180°C in a stream of -a elementary air. Run the reaction for minutes.

Next, trimellitic anhydride is added and the temperature is raised to 210°C. The reaction was kept at 210° C. for 15 hours. The resin concentration was adjusted to 30% by weight with cresol to obtain a festival. The viscosity of this product was 250 poise. The infrared absorption spectrum shows imide group absorption at 1.780 cm-''.

Absorption of amide group was observed at 1.650o-.

(Fill Manufacture of composite sheet Aromatic polyamide paper (DuPon).

Product name: Nomex 410. A 0.025 mm thick calendar product) was pre-dried at 20°C'x for 30 minutes, then the entire dip coating synthesized in (1) was applied to both sides, and after drying at 160°C for 30 minutes, further 250℃
After drying for 30 minutes, a composite sheet with a thickness of 0.050 cm was obtained.

Example 2 Aromatic polyamide paper (product of Nippon Aroma Co., Ltd.) was dried at 120°C for 30 minutes, and then a diluted cresol solution of the cresol-soluble polyamide-imide resin synthesized in Example 1 (1) (resin content: 10 weight) was dried at 120°C for 30 minutes. impregnated with
After drying at 160° C. for 30 minutes, drying was further carried out at 250° C. for 30 minutes to obtain a composite sheet with a thickness of 0.075 cm.

Example 3 +11 Preparation of polyamideimide resin face containing epoxy resin (1) Synthesis of polyamideimide resin soluble in cresol solvent Trimesic acid 14.0 0.2 Trimelizic anhydride 76.8 0.84.4'-Diphenylmethane Diiso 113.8 0.91 Cyanate C-caprolactam 33.9 0.60 Cresol 159.0 Silene
5.0 Put the above ingredients except trimesic acid and trimellitic anhydride into a four-loaf flask equipped with a thermometer, a stirrer, and a fractionating tube, and bring the temperature to 180°C in a nitrogen stream.
C. and reacted for 90 minutes. Next, the temperature is lowered to 160°C, trimesic acid and trimellitic anhydride are added, and the temperature is raised to a temperature at which cresol refluxes. At this temperature 1
The reaction was allowed to proceed for 0 hours. Tree flavor concentration 23 with cresol
Weight (percent) K was prepared to obtain a polyamide-imide resin. The solution viscosity of this product is 83 poise (30°C), @original pressure viscosity is 027 (0,5)/dimethylformamide 1
00ml solution).

(11) Epoxy! Preparation of polyamide-imide resin varnish containing the 'l1II effect (Epicor) 1004 in a resin content of 15 parts by weight and 1 part by weight per 100 parts by weight of the polyamide-imide resin obtained in (1).
(epoxy resin manufactured by Shell, trade name) was added with stirring to obtain a uniform fest.

(Fill Manufacture of composite sheet Aromatic polyamide paper (DuPont Company).

Product name: Nomex-E 54A (0.075 m thick, 1° calendered product) was dried at 120°C for 130 minutes, and then a polyamide-imide resin composition containing 9 epoxy resin was synthesized on both sides with (:). Coated at 160℃%3
After drying for 0 minutes.

1 Drying was carried out at 250°C for 730 minutes to obtain a composite sheet with a thickness of 0.100 cm.

Table 1 shows the composite sheet obtained in Example 1.2 and the aromatic polyamide paper alone (Du P
on1 company, product name: Nomex410 thickness o, osm
calendar product), polyimide film (Du Pon
1 company, product name: Ka p t on thickness 0.0511
11>.

It is shown that properties such as water absorption rate and solder shrinkage rate are significantly improved by treatment with the above-mentioned polyamide-imide resin. Furthermore, it can be seen that the properties of the composite sheet according to the present invention, when compared with polyimide films, have the properties necessary as a material for a flexible printed circuit board.

Continuation of page 1 0 shots clear person Isao Uchigasaki Hitachi 4-13-1 Higashimachi, Hitachi City Kasei Kogyo Co., Ltd. Yamazaki Factory 0 shots: Yoshiyuki Mukaiyama Hitachi 4-13-1 Higashimachi, Hitachi City Kasei Kogyo Co., Ltd. Ibaraki Research Institute

Claims (1)

[Claims] 1. A hanging sheet formed by coating aromatic polyamide vapor with a polyamide-imide resin composition using a cresol solvent, impregnating the same, and then heating and drying the composition. 2. The polyamide-imide resin composition contains incyanurate ring-containing polyisocyanate, diisocyanate, and lactam in a cresol solvent. General formula other than tricarboxylic anhydride and tricarboxylic acid anhydride X-R-G-Y)nt (X,
X' may be the same or different, carboxyl group or acid anhydride group, Y is carboxyl group, acid anhydride group, hydroxyl group, or amino group, R is →Rt +FEZ +
Rv +7 - aromatic, aliphatic. a cyclic or heterocyclic group residue, provided that Rt and R3 may be the same or different; aromatic, aliphatic, am group or heterocyclic group residue; 2 is -C-ru; -CO-, -801- or -〇-0m and j are integers of 1 or 2, and n is an integer of 1 or more]. ~30 equivalent percent, obtained by reacting a compound represented by the general formula # of the patent claim is a polyamideimide resin composition with a weight percent of ~40%! 8. Composite sheet according to item 1. 1 Isocyanurate ring-containing polyisocyanate is 44
Patent #11, which is an isocyanurate ring-containing polyisocyanate obtained from '-diphenylmethane diisocyanate, trilenosyinoaanate, and isophorone diisocyanate! Composite sheet as described in item 2 of the box. 4. The composite sheet according to claim 2 or 3, wherein the diisocyanate is 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyl ether diisocyanate, tolylene diiso/anate, or xylylene diisocyanate. 5. The composite sheet according to claim 2, 3, or 4, wherein the lactam is C-caprolactam. X' 6, general formula X-)t-+Y). The compound represented by -8. Polyisocyanate containing trimesic acid, tris(2-carboxyethyl)ine cyanurate, λλ'4,4'-benzophene, nontetracarboxylic dianhydride or isocyanurate, and polycarboxylic acid containing an acid anhydride group Claims 2 and 3 are reaction products. The electrically insulating composite sheet according to item 4 or 5. 7. Claims 2 and 3, wherein the tricarboxylic acid anhydride is trimellit 1llfi hydrate. Composite sheet according to item 4, 5 or 6. & Claim dX1, wherein the polyamide-imide resin is a polyamide-imide resin containing a thermosetting resin,
Section 2, Section 3, Section 4. Composite sheet according to item 5, 6 or 7. 9. The composite sheet according to claim 8, wherein the thermosetting resin is an epoxy resin, an alkoxy-modified melamine resin, or a phenol formaldehyde resin.