JPH0665697B2 - Flexible heat resistant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an aromatic polyamide-imide resin composition used in many fields such as electronic materials and films which are both flexible and heat resistant.

[Conventional technology and its problems]

In recent years, along with the development of the electronics field, the tendency toward lightness, thinness, shortness and miniaturization, that is, miniaturization and high functionality has been spurred, and new characteristics and advanced functions are also required for material parts in the field.

In particular, the emergence of a material having both heat and humidity dimensional stability and flexibility is strongly desired in the field.

Conventionally, a polyimide resin represented by Kapton is well known as a material having both heat resistance and flexibility at the same time. However, polyimide resins must have excellent electrical properties, mechanical properties, heat resistance and flexibility, but they have problems in dimensional stability during heat and humidity, and they are easy to process and easy to use. It is a resin material that also needs improvement.

In addition, a solvent-soluble polyamide-imide resin has been proposed in order to improve the processability and usability of this polyimide resin. (See, for example, Japanese Patent Publication No. 49-35076)
This is also true that the thermal decomposition start temperature or the physical properties of the substrate such as the glass transition point has heat resistance and also has flexibility, but on the practical side, for example, in the case of a flexible printed circuit board, the warpage is large, Blisters and dimensional shrinkage occur when the solder is heat resistant. Furthermore, when used as an overcoat of a wiring board, the resin still has many problems in practice, such as swelling, wrinkles, and peeling during heat-resistant soldering (300 ° C, 10 seconds). Is the current situation.

A method of adding an inorganic filler to an aromatic polyamide-imide resin has also been proposed (see Japanese Patent Publication No. 57-26700), but this improves heat resistance but loses flexibility and adhesiveness of the liver and kidneys. The problem is that

Thus, it has heat and humidity dimensional stability and flexibility, and is easy to process.
Although there are strong needs for easy-to-use materials, the reality is that they are not on the market.

[Problems to be solved by the invention]

INDUSTRIAL APPLICABILITY The present invention provides a resin material having heat and humidity dimensional stability and flexibility that have not been put on the market even though they are strongly demanded as described above and can be processed by a simple method such as printing or coating. Is what you are trying to do.

[Means for solving problems]

That is, the present invention has the general formula (Provided that X represents an oxygen atom, a sulfur atom, a sulfonyl group, a carbonyl group or a methylene group, and n represents an integer of 2 or more), and the polar organic solvent-soluble aromatic polyamideimide resin 95 to 65% by volume and particles Mica 5 with a diameter of 1 to 500 μm
It is a flexible heat-resistant resin composition, characterized in that it is composed of ˜35% by volume.

If the particle size, shape, and type (origin) of mica, which is an essential component of the present invention, are made appropriate, excellent heat resistance and flexibility can be obtained, and it is excellent compared to other fillers. Thus, transparency and flatness can be obtained. This was an unexpected effect that was not initially planned.

Hereinafter, the present invention will be described in detail.

The aromatic polyamide-imide resin used in the present invention is a polar organic solvent-soluble aromatic polyamide-imide resin having the general formula (However, X represents an oxygen atom, a sulfur atom, a sulfonyl group, a carbonyl group or a methylene group, and n represents an integer of 2 or more), or a mixture thereof.

The reduced viscosity of the aromatic polyamideimide resin used in the present invention is not particularly limited as long as it is 0.5 or more, but it is practical that the solution viscosity at the time of use is up to about 3.5. If the reduced viscosity is too low, the mechanical strength and flexibility will decrease, and if the reduced viscosity is too high, the solubility in polar organic solvents will decrease, making it impractical.

These aromatic polyamide-imide resins are known methods,
For example, it can be produced by reacting an aromatic diamine with trimellitic anhydride chloride or by reacting an aromatic diisocyanate with a bisimide dicarboxylic acid.

The reaction among them will be described below as a typical example.

An aromatic diamine (wherein X in the formula has the same meaning as described above) and trimellitic anhydride chloride are reacted in a polar organic solvent such as N, N-dimethylacetamide or N-methyl-2-pyrrolidone.

Examples of the aromatic diamine (A) include 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminobenzophenone, 4,4 '. Mention may be made of diaminodiphenylmethane.

Further, among the aromatic diamine of (A) and the aromatic diamine of m-phenylenediamine, the aromatic diamine of (A) which is excellent in flexibility, heat resistance and moisture resistance is more preferable.

As the polar organic solvent of the aromatic polyamideimide resin of the present invention, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, N-methyl-2-
Pyrrolidone, hexamethylsulfolamide, halogenated cresol, a mixed solvent thereof, or a mixed solvent of these and another conventional solvent can be mentioned.

The mica used in the present invention may be either natural mica or synthetic mica. The grain size is 1 to 500 μm, but especially 50 to 2
It is preferably 00 μm.

The plate-like, layer-like, and scale-like ones that ordinary mica has are suitable for the shape.

The mixing ratio of mica is 5 to 35% by volume, preferably 10
~ 25% by volume.

This blending ratio is important, and if the blending ratio is too high, mechanical strength and flexibility (flexibility) decrease, which is not desirable.

On the other hand, if the blending ratio is too low, the dimensional stability at the time of heat and humidity, which is another feature of the present invention, will be problematic, so it must be avoided.

That is, outside the range of the mica compounding ratio of the present invention, 300 ° C when a film or a flexible copper clad substrate is used.
・ In a 20-second solder immersion test, blistering, warping, etc. occur, and warping due to moisture absorption also causes dimensional stability under heat and humidity.

The composition of the present invention, the polar organic solvent which substantially dissolves the aromatic polyamide-imide resin, 230 to 9900 parts by weight to 100 parts by weight of the aromatic polyamide-imide resin, the mica is uniformly dispersed in this mixture. It can be used in the form. This solvent-containing composition is suitable for use as a paint or adhesive.

As a method for producing the composition containing the solvent of the present invention, a conventionally known method can be used. For example, it can be produced by adding an aromatic polyamide-imide resin to a polar organic solvent, completely dissolving it, then adding mica, and uniformly dispersing it with a kneader, a ball meal, a three-roll mill or the like.

A flexible heat-resistant resin composition can be obtained by evaporating the solvent from the composition to which the solvent is added by ordinary heating, vacuum heating, heating with far infrared rays, or by removing the solvent by other methods. If the mica is oriented and present in the resin, the transparency and the flatness of the surface are improved. Therefore, it is desirable that the mica be arranged in a certain direction as much as possible.

If desired, various additives may be added to the composition of the present invention. One example is adding a silane coupling agent, glass powder, glass fiber, heat-resistant fiber, or the like in order to enhance the adhesiveness or mechanical strength.

(Effects of the Invention) As described above, the flexible heat-resistant resin composition of the present invention has excellent heat resistance and moisture resistance, has transparency, plane smoothness, and has good adhesiveness, mechanical strength, It has electrical characteristics and is excellent in flexibility and workability. In particular, the transparency and plane smoothness peculiar to the composition of the present invention can be said to be an extremely valuable effect depending on the application.

INDUSTRIAL APPLICABILITY The composition of the present invention is a material for electronic parts, in particular, the above-mentioned transparency and planar smoothness are utilized, and is suitably used for a flexible printed circuit board. In addition, other electronic parts materials, for example, heat- and moisture-resistant films and sheets. It can also be applied to paints, inks, adhesives and the like. It can also be widely applied as a general heat resistant material.

EXAMPLES Next, the present invention will be described with reference to Examples and Comparative Examples.

The measured values shown in the following examples are obtained by the following measuring method and apparatus.

Water vapor permeability JIS Z0208 was used.

A test piece having a thickness of 0.1 mm was measured by the cup method under the conditions of 40 ° C. and 90% RH.

Folding resistance It was performed according to JIS P8115.

Using an MIT tester, a test piece with a width of 15 mm and a thickness of 50 μ was R = 0.
It was measured at 38 and a tension of 0.5 Kg.

Tensile strength Using Tensilon tensile tester manufactured by Toyo Baldwin,
A test piece with a width of 6 mm and a thickness of 100 μ has a pulling distance of 50 mm and a pulling speed of 10 mm.
/ Min was measured.

Solder heat resistance (curl degree) A test piece was immersed in solder at 300 ° C for 20 seconds, then pulled up and cooled to room temperature, and the curl degree was measured by the following method.

A 1-inch wide test piece is placed on a flat surface. Next, measure the maximum distance between the curved surface of the test piece and the plane reference surface in mm,
This was defined as the curl degree.

Adhesiveness It measured by the cross cut-tape method.

A coating film with a thickness of 50 mm is formed and used as a test piece. After cross-cutting this test piece according to the JIS K5400 cross-cut test, a PET tape was attached and then peeled off to count the remaining squares in 100 squares.

Example 1 A polar organic solvent-soluble aromatic polyamideimide (PAI; reduced viscosity 1.) synthesized from 4,4'-diaminodiphenyl ether (DADPE) and trimellitic anhydride chloride (TMAC).
4) 100 parts by weight of N-methyl-2-pyrrolidone (NMP) 490
Add parts by weight to dissolve the PAI.

Mica (Tamaki Mica, particle size 149μ)
m) 48 parts by weight of N-methyl-2-pyrrolidone (NMP) 90
The solution dispersed in parts by weight and the PAI resin solution were mixed, and the mica was uniformly dispersed with a kneader to obtain a paste-like resin composition. This resin composition consists of 80% by volume PAI and 20% by volume mica.

This paste composition was cast on a glass substrate and heated at 90 ° C.
The film is dried at 130 ° C. for 30 minutes, and then peeled off from the glass substrate to obtain a film-like material in a touch-free state. The film-like material was sandwiched between cylindrical jigs and dried at 190 ° C., 250 ° C., and 300 ° C. for 20 minutes to completely evaporate the solvent.

Physical properties of the film-shaped heat-resistant resin composition comprising 80% by volume of PAI and 20% by volume of mica thus obtained were measured by the above-mentioned measuring methods. Moisture vapor transmission rate: 3.5 g / m ² · 24Hr · 100 μm Tensile strength: 8.1 kg / mm ² , which was excellent in insulating property, strength and moisture resistance.

Similarly, when a film having a thickness of 40 μm was prepared and subjected to a bending resistance test, it was found to have excellent flexibility of 2850 times.

The film was subjected to a solder dipping test at 300 ° C. for 20 seconds, and the result was that the curl degree was 0.05 mm and the heat resistance was excellent.

Next, the paste composition was applied onto a 35 μm copper foil, the solvent was volatilized to form a dry coating film with a thickness of 40 μm, and the adhesiveness was tested by the cross-cut method to be 100/100. It was excellent.

Examples 2-5 Points using various PAIs, types and amounts of mica,
Further, a film-like material was obtained by the same method as in Example 1 except that the solvent was changed, and various physical properties were measured.

The results are shown in Table 1.

Comparative Examples 1 to 4 Examples in which mica is not added (Comparative Examples 1 and 2), examples in which mica is excessively added (Comparative Example 3), and examples in which PAI containing m-PD as an aromatic diamine component (Comparative Example 4) are used, respectively. Table 1 shows a comparative example.

In addition, the manufacturing method and the measuring method of the film-like material of the comparative example are the same as those of the example.

Continuation of the front page (72) Minako Kotani Minako Otani 648 Hirookaue, Haruno-cho, Agawa-gun, Kochi Prefecture Nippon Kogyo Paper Co., Ltd. (56) References JP-A-49-87746 (JP, A) JP-A-55- 7838 (JP, A) JP-B 57-10130 (JP, B2) JP-B 57-26700 (JP, B2) Yoshinori Abe et al. "New edition plastic compounding agent-basic and application" Published by Taiseisha 1984 , 117-118, edited by Shu Kambara et al., "Practical Handbook of Additives for Plastics and Rubbers", published by Chemical Engineering Co., 1977, p. 598

Claims (1)

[Claims] 1. A general formula (Provided that X represents an oxygen atom, a sulfur atom, a sulfonyl group, a carbonyl group or a methylene group, and n represents an integer of 2 or more), and the polar organic solvent-soluble aromatic polyamideimide resin 95 to 65% by volume and particles Mica 5 with a diameter of 1 to 500 μm
A flexible heat-resistant resin composition, characterized in that it comprises from 35 to 35% by volume.