JPH0456864B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Application of the Invention) The present invention relates to a heat-resistant resin composition with improved adhesion and the like. (Background of the Invention) Polyamide-imide varnishes, polyimide varnishes, polyester-imide varnishes, and polyamide-imide ester varnishes are conventionally known as heat-resistant resin compositions, particularly varnishes for heat-resistant enameled wires. Among these, varnishes using resins in which polyester is modified with imide bonds or amide-imide bonds, such as polyester imide varnish and polyamide imide ester varnish, are often used from the viewpoint of a balance between properties and price. However, polyester imide varnish and polyamide imide ester varnish are manufactured using relatively inexpensive materials, so although they are superior in terms of economy (price), they have the disadvantage of poor adhesion, especially in terms of wire diameter. There was a problem when using a thick film on a thick heat-resistant enameled wire. (Objective of the Invention) An object of the present invention is to eliminate the drawbacks of the above-mentioned conventional techniques and to provide a heat-resistant resin composition having excellent adhesiveness and the like. (Summary of the Invention) In order to achieve this objective, the present inventors conducted various studies on improving the adhesion of polyester imide varnish, and as a result, discovered that the adhesion of polyester imide varnish to which melamine was added was excellent. We have arrived at the present invention. The present invention has an imide bond in the molecular chain and at least a part of the alcohol component is tris-2-
Polyester resin made into hydroxyethyl isocyanate and for the polyester resin
The present invention relates to a heat-resistant resin composition containing 0.03 to 5% by weight of melamine. The polyester resin having an imide bond in the molecular chain used in the present invention (hereinafter referred to as polyester imide resin) has, for example, the following general formula () (wherein R is a divalent organic group). Imidic acid represented by the general formula () is, for example, 2 trimellitic anhydride per 1 mole of diamine or diisocyanate.
Obtained by reacting moles (Special Publication 1977)
-Refer to Publication No. 40113). Examples of diamines used in this case include aromatic diamines such as 4,4'-diaminodiphenylmethane, p-phenylenediamine, and m-phenylenediamine, and aliphatic diamines such as hexamethylenediamine. Aromatic diamines are preferred in terms of heat resistance. The diisocyanate is not particularly limited, and aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate and toluylene diisocyanate are preferred. There are no particular restrictions on the method for producing imidic acid, but
For example, the reaction between diamine and trimellitic anhydride is
It is carried out at a temperature of 120-250°C in the presence of a polar solvent such as cresol, phenol or N-methylpyrrolidone. Production of imide acid can be confirmed by distillation of water generated during production of imide acid. The amount of imide acid used is 10 to 60% equivalent of the total acid component, from the viewpoint of heat resistance and economic efficiency (the effective resin content decreases when the resin composition is adjusted to an appropriate viscosity as an enameled wire varnish). % is preferred. As the acid component of the polyesterimide resin, in addition to the above-mentioned imide acid, terephthalic acid, isophthalic acid, or derivatives thereof such as dimethyl terephthalate and dimethyl isophthalate are used. In addition, at least a portion of the alcohol component contains Tris-
2-hydroxyethyl isocyanurate is used, and other alcohol components include dihydric or higher alcohols, such as ethylene glycol, neopentyl glycol, 1,4-butanediol, 1,
Dihydric alcohols such as 6-hexanediol and 1,6-cyclohexanedimethanol, and trihydric or higher alcohols such as glycerin, trimethylolpropane, and pentaerythritol are used. From the viewpoint of heat resistance, it is preferable to use tris-2-hydroxyethyl isocyanurate in an amount of 30 equivalent % or more, particularly preferably 50 to 100 equivalent %, of the alcohol component. When producing a polyesterimide resin, the equivalent ratio of the acid component to the alcohol component is preferably an alcohol excess of 1 to 80%. When the acid component and the alcohol component are reacted by heating, there are no particular limitations as long as the conditions are such that the esterification reaction and the transesterification reaction occur substantially. For example, tetraalkyl titanates, lead acetate,
It is carried out at temperatures of 120-240°C in the presence of trace amounts of an esterification catalyst such as dibutyltin dilaurate. Further, the synthesis may be carried out in the presence of a solvent such as cresol depending on the viscosity. When producing polyester imide resin, (1) first synthesize imide acid, then add the remaining polyester components (acid component and alcohol component) and esterify it, (2) react all components simultaneously to imidize. There are various synthesis methods, such as (3) reacting the polyester components other than the imide acid component in advance and then adding the imide acid component to perform imidization and esterification, but there are no particular restrictions. There isn't. The amount of melamine used in the heat-resistant resin composition of the present invention is 0.01 to 5% by weight, preferably 0.02 to 0.2% by weight based on the polyesterimide resin.
It is said that If the amount of melamine added is less than 0.03% by weight, the adhesion will not be sufficiently improved, and if it exceeds 5% by weight, the deterioration resistance will decrease. The heat-resistant resin composition of the present invention is produced by dissolving a polyesterimide resin and melamine in a solvent and adjusting the viscosity to an appropriate value. The solvent used at this time is not particularly limited as long as it dissolves both the polyesterimide resin and melamine, but for example, phenolic solvents such as cresol, phenol, and xylenol are used. Furthermore, as a co-solvent, for example, xylene,
NISSEKI HISOL−100, 150 (Japan Petrochemical Co., Ltd.)
(trade names of aromatic hydrocarbons), methyl ethyl ketone, dimethyl succinate, methyl carbitol, etc. can also be used. The heat-resistant resin composition of the present invention contains 20 to 50% by weight of polyesterimide resin and melamine in total.
It is preferable that the solvent be contained in a proportion of 80 to 50% by weight. The heat-resistant resin composition of the present invention may optionally include:
For example, titanium compounds, polyisocyanate dienelators, organic acid metal salts, polyamide resins, polyhydantoin resins, alkoxy-modified amino resins, polysulfone resins, phenol resins, etc. are contained in a proportion of 0.1 to 25% by weight based on the resin content. Good too. The resin composition of the present invention is made into an insulated wire by a conventional method by applying and baking it directly onto an electric conductor or together with another insulating film. The heat-resistant resin composition of the present invention is widely used in heat-resistant insulated wires, heat-resistant paints, and the like. (Effects of the Invention) The heat-resistant resin composition of the present invention has significantly superior adhesion and flexibility compared to conventional heat-resistant resin compositions by blending melamine with polyesterimide resin. It is a heat-resistant resin composition that does not show any deterioration in various properties such as thermal shock resistance and softening resistance. (Examples of the Invention) The present invention will be explained below with reference to Examples. Production example (synthesis of polyesterimide resin) Diaminodiphenylmethane 108.8g (35 equivalents),
Trimellitic anhydride 211.0g (70 equivalents), dimethyl terephthalate 198.0g (65 equivalents), ethylene glycol 14.6g (15 equivalents), tris-2-hydroxyethyl isocyanurate 368.8g (135 equivalents),
300.0 g of cresol and 0.4 g of tetrabutyl titanate were placed in a four-necked flask equipped with a thermometer and a stirrer, and the reaction was carried out at 170°C for 1 hour while refluxing toluene, and the azeotropic water was removed. This liquid was then distilled off while distilling off the toluene.
The temperature was raised to 210°C and the temperature was kept until gelation time on a gel plate at 250°C reached 120 seconds. Then cresol
Add 650gHISOL-100 238g and lower the temperature to 100℃
Tetrabutyl titanate and then further reduced to
15.9 g of zinc naphthenate, 26.5 g of zinc naphthenate, and 23.7 g of VP-51 (phenol resin, manufactured by Hitachi Chemical Co., Ltd.) were added. Non-volatile content of the obtained resin composition (200℃-
(heated for 2 hours) was 41% by weight, and the viscosity (30°C) was 42 poise. Example 1 0.4 g of melamine was added to 1000 g of the resin composition produced in Production Example, and the mixture was stirred at 60° C. for 1 hour to obtain a uniform solution. Example 2 Terephthalic acid 191.8g (70 equivalents), ethylene glycol 30.7g (30 equivalents), tris-2-hydroxyethyl isocyanurate 344.5g (120 equivalents),
300g of cresol and dibutyltin dilaurate
0.8 was placed in a four-necked flask equipped with a thermometer and a stirrer, the temperature was raised to 210°C, and the reaction was allowed to proceed until the unreacted residue of the terephthalic acid content could no longer be visually observed. The temperature was then lowered to 100°C, 98.0g (30 equivalents) of diaminodiphenylmethane and 190.1g (60 equivalents) of trimellitic anhydride were added, and the temperature was raised to 170°C. Furthermore, 30 g of toluene was added, and the azeotropic water was removed while refluxing, and the mixture was kept warm for 1 hour. Next, while toluene was distilled off, the temperature of this liquid was raised to 210°C, and the temperature was kept until gelation time on a gel plate at 250°C reached 90 seconds. Then 700 g of cresol and 250 g of HISOL-100 were added, and after the temperature was lowered to 105°C, further 16.0 g of tetrabutyl titanate, 22.0 g of zinc naphthenate and
VP-51 (phenolic resin, manufactured by Hitachi Chemical Co., Ltd.)
26.5g was added, and further 1.0g of melamine was added. Non-volatile content of the obtained resin composition (200℃-2
The viscosity (at 30° C.) was 62 poise. Example 3 Diaminodiphenylmethane 123.6g (40 equivalents),
239.6 g (80 equivalents) of trimellitic anhydride, 181.6 g (60 equivalents) of dimethyl terephthalate, Tris-2-
Hydroxyethyl isocyanurate 434.3g (160
equivalent), 450 g of cresol and 0.4 g of tetrabutyl titanate were added to a
The mixture was placed in a neck flask, and the reaction was carried out at 170°C for 1 hour while refluxing toluene, and the azeotropic water was removed. Next, while toluene was distilled off, this liquid was heated to 205°C and kept at this temperature until gelation time on a gel plate at 250°C reached 140 seconds. Next, 650 g of cresol and 288 g of HISOL-100 were added, followed by 16.2 g of tetraisopropyl titanate, 20.0 g of zinc naphthenate, 23.7 g of VP-51 (phenolic resin, manufactured by Hitachi Chemical Co., Ltd.), and 0.6 g of melamine. Non-volatile content of the obtained resin composition (20℃
- heating for 2 hours) was 38% by weight, and the viscosity (30°C) was 45 poise. The resin compositions obtained in Production Examples and Examples 1 to 3 were baked on copper wires with a diameter of 1 mm with a type 0 finish under the following conditions to obtain insulated wires, and the properties of the wires were measured. The results are shown in Table 1.

【table】

[Table] As is clear from the results in Table 1, in the case of the examples of the present invention, the lifting of the film during sudden cutting, which is one of the evaluation methods for adhesion, was lower than that in the case where melamine was not added ( Compared to the 12mm of the comparative example, this is a marked improvement of 2 to 3mm, and the twisting is also extremely improved, and the properties of flexibility, thermal shock resistance, and softening resistance have not deteriorated. It is shown that

Claims (1)

[Claims] 1 A polyester resin having an imide bond in the molecular chain and at least a part of the alcohol component being tris-2-hydroxyethyl isocyanurate, and 0.03 to 5
% by weight of melamine.