JP3191250B2 - Manufacturing method of roughened polyimide film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roughened polyimide film. More specifically, the present invention relates to a method for producing a roughened polyimide film having improved lubricity and adhesion. The surface-roughened polyimide film of the present invention has fine irregularities on its surface, and has excellent physical properties such as lubricity, adhesiveness, and heat resistance. it can.

[0002]

2. Description of the Related Art Generally, an aromatic polyimide film is formed by casting a solution of a polyamic acid or a polyimide solution on a support to form a thin film, drying the thin film, and peeling the thin film from the support. Thereafter, it is manufactured by heat treatment at a higher temperature. However, the polyimide film produced by such a method has a drawback that the surface is very smooth and the slipperiness is poor, so that it is difficult to use the film as a tape.

Hitherto, as a method for facilitating lubrication of an aromatic polyimide film, a method of adding inorganic fine particles to a film has been proposed as described in, for example, JP-A-61-246919. In addition, a method of adding organic fine particles and a method of coating fine particles on the film surface have been proposed. However, the fine particles aggregate, causing abnormal projections, and it is difficult to uniformly roughen the surface. Further, it is difficult to apply the coating method continuously and uniformly.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to cause abnormal projections on the surface while maintaining the excellent physical properties and heat resistance inherent to the aromatic polyimide film at a high level. An object of the present invention is to provide a method for producing a roughened aromatic polyimide film having fine irregularities on the surface of a film without adding fine particles.

[0005]

According to the present invention, there is provided a solution of a palladium salt on the surface of an aromatic polyimide film obtained from an aromatic tetracarboxylic acid component and an aromatic diamine, or an aromatic polyamic acid film as a precursor thereof. After the application, the object of the present invention was achieved by heating at a temperature of 300 ° C. or higher.

The aromatic polyimide or aromatic polyamic acid according to the present invention is obtained from (1) an aromatic tetracarboxylic acid component and (2) an aromatic diamine component, and (1) an aromatic tetracarboxylic acid component. As, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3', 4'-biphenyltetracarboxylic acid, or their acid dianhydride, or the lower alcohol ester of those acids Biphenyltetracarboxylic acids, or 3,3 ′, 4,4′-benzophenonetetracarboxylic acid or its acid dianhydride, bis (3,4-
Dicarboxyphenyl) methane or its acid dianhydride, 2,
2-bis (3,4-dicarboxyphenyl) propane or an acid dianhydride thereof, bis (3,4-dicarboxyphenyl) thioether or an acid dianhydride thereof, bis (3,4-dicarboxyphenyl) sulfone or An aromatic tetracarboxylic acid component composed of the acid dianhydride, pyromellitic dianhydride, an anhydride of the acid, or a mixture thereof is exemplified.

(2) As aromatic diamine components, phenylene diamine compounds such as paraphenylenediamine and metaphenylenediamine, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether and the like Diphenyl ether diamine compound, 4,4'-diaminodiphenylmethane, diphenylmethane diamine compound such as 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenylpropane, 4,4'-
Diphenylpropane diamine compounds such as diaminodiphenylpropane, 4,4'-diaminodiphenylsulfide, diphenylsulfide-based diamine compounds such as 3,3'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, and 3,3'- Examples thereof include diphenylsulfone-based diamine compounds such as diaminodiphenylsulfone, and aromatic diamine components such as 3,3′-dimethylbenzidine.

The aromatic tetracarboxylic acid component includes 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′,
4'-biphenyltetracarboxylic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, or an acid dianhydride thereof is preferable, and as the aromatic diamine component, paraphenylenediamine, 4,4'-diamino Diphenyl ether and the like are preferred.

In the production method of the present invention, the organic solvent used for the aromatic polyamic acid solution or the like for film formation includes:
Any material capable of uniformly dissolving the aromatic polyamic acid may be used, for example, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N, N-diethylformamide, hexamethylsulfolamide Amide organic polar solvent such as amide, dimethyl sulfoxide, sulfoxide organic polar solvent such as diethyl sulfoxide,
Sulfone organic polar solvents such as dimethyl sulfone and diethyl sulfone; N-methyl-2-pyrrolidone;

The method for producing an aromatic polyamic acid used in the present invention comprises the steps of using the above-mentioned aromatic tetracarboxylic acid component and aromatic diamine component in approximately equimolar amounts in the above-mentioned organic polar solvent. 100 ° C or less, especially 60 °
A method of producing an aromatic polyamic acid by polymerizing at a temperature of C or lower. The amounts of the two components used do not necessarily need to be exactly equimolar, and any one component is
If it is within 10 mol%, especially within 5 mol% with respect to other components, it may be used in excess.

In the polymerization reaction of the present invention, the total monomer concentration in the organic polar solvent is 5 to 40% by weight, preferably 6 to 40% by weight.
It is preferably from 35 to 35% by weight, particularly preferably from 10 to 30% by weight.

The aromatic polyamic acid solution used for producing the aromatic polyimide film of the present invention has a temperature of 30 ° C.
Is preferably about 0.1 to 50,000 poise, particularly about 0.5 to 30,000 poise, and more preferably about 1 to 10,000 poise from the viewpoint of handling workability. Therefore, it is preferable that the above-mentioned polymerization reaction proceed until the viscosity of the generated aromatic polyamic acid solution reaches the above-mentioned viscosity.

In the present invention, for producing an aromatic polyimide film, for example, the above-mentioned aromatic polyamic acid solution is applied to a suitable support (for example, a roll or metal belt made of metal, ceramics, plastics, or a metal thin film tape). Is rolled on the surface of a roll or belt) to which about 10 to 2,000 μm, especially 20 to
Forming an aromatic polyamic acid solution having a uniform thickness of about 1,000 μm in a film state, and then heating to 60 to 160 ° C. using a heat source such as hot air or infrared rays to gradually remove the solvent. To pre-dry until the film becomes self-supporting, and the self-supporting film is peeled from the support. As the aromatic polyimide film, the self-supporting film is
It is obtained by heating to a temperature of 00 ° C. or higher.

In the present invention, the surface-roughened aromatic polyimide film is coated with a palladium salt solution on the surface of the self-supporting aromatic polyamic acid film or the surface of the aromatic polyimide film, and then dried at 300 ° C. C
By heating to the above temperature, the film is manufactured by providing fine irregularities on the surface of the film.

As the palladium salt used in the present invention, palladium chloride, palladium acetate, palladium nitrate, palladium sulfate and the like are preferably exemplified. As a solvent for the palladium salt, water, N-methyl-2-pyrrolidone, N,
N-dimethylacetamide, methanol, ethanol, dioxane, tetrahydrofuran, etc., alone or in combination.

The concentration of the palladium salt solution is 0.0001
A mole / liter to 0.1 mole / liter is preferred. If the concentration is higher than this, the surface is roughened, but the surface roughening does not proceed, so that it is not economical. If the concentration is lower than this, the aromatic polyimide film is not roughened, so the above range is preferable.

In the present invention, the method of applying the palladium salt solution includes a commonly used coater, for example, a gravure coater, a doctor coater, a doctor blade, a reverse roll coater, or a dipping method. When applying a palladium salt solution to the surface of the self-supporting aromatic polyamic acid film, no pretreatment is required. Even when applying a palladium salt solution on the surface of the aromatic polyimide film, no special pretreatment is required,
When the palladium salt solution does not uniformly wet the surface of the aromatic polyimide film, the surface of the aromatic polyimide film is treated with an alkaline solution to improve wettability, and then the palladium salt solution is applied. preferable.

In the present invention, the alkaline solution used as the pretreatment is a known solution such as water such as potassium hydroxide, sodium hydroxide, aliphatic amine, or aliphatic diamine, or an alcohol-based or amide-based solution. Can be used.

[0019]

EXAMPLES Examples and comparative examples are shown below. Example 1 0.5 mol of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 0.5 mol of paraphenylenediamine and 90 mol
0 g of N, N-dimethylacetamide was charged into a 2 liter glass flask and polymerized at 25 ° C. for 4 hours to obtain a reaction solution of an aromatic polyamic acid (polymer concentration: 1).
(0% by weight, solution viscosity at 25 ° C: 500 poise) was cast on a glass plate to form a film of a polyamic acid solution, and the film was dried with hot air at 80 ° C for 30 minutes to evaporate the solvent. After leaving, a polyamic acid film was formed. The obtained polyamic acid film was peeled off from the glass plate, and one side of palladium chloride containing 0.002 mol / L of N,
After applying an N-dimethylacetamide solution with a doctor blade, drying at 100 ° C. for 12 minutes,
To 420 ° C. in 10 minutes, and heat-treated at this temperature for 20 minutes. The surface of this film is shown in FIG. 1, and fine irregularities were formed in the range from 0.1 to 3 μm from convex to convex.

Example 2 A polyamic acid film was prepared in the same manner as in Example 1. This polyamic acid film was cured at 200 ° C. for 10 minutes.
And then heated at 420 ° C. for 5 minutes to obtain an aromatic polyimide film. This aromatic polyimide film is first immersed in a 10% aqueous solution of sodium hydroxide for 40 minutes, washed with water, immersed in a 0.005 mol / liter N, N-dimethylacetamide solution of palladium chloride, and then heated at 200 °
From 420 ° C to 420 ° C in 10 minutes.
Heat treated for minutes. Fine irregularities similar to those in Example 1 were formed on the surface of the aromatic polyimide film.

Comparative Example 1 A polyamic acid film was prepared in the same manner as in Example 1, and this polyamic acid film was cured at 200 ° C. for 10 minutes.
And then heated at 420 ° C. for 5 minutes to obtain an aromatic polyimide film. The aromatic polyimide film was first immersed in a 10% aqueous solution of sodium hydroxide for 40 minutes, washed with water, heated from 200 ° C. to 420 ° C. in 10 minutes, and heat-treated at this temperature for 20 minutes. Unlike the examples, the surface of the aromatic polyimide film was smooth and did not have fine irregularities.

Comparative Example 2 A polyamic acid film was prepared in the same manner as in Example 1. This polyamic acid film was cured at 200 ° C. for 10 minutes.
And then heated at 420 ° C. for 5 minutes to obtain an aromatic polyimide film. This aromatic polyimide film was washed with water and heated from 200 ° C to 420 ° C in 10 minutes,
Heat treatment was performed at this temperature for 20 minutes. The surface of this aromatic polyimide film was the same as in Comparative Example 1. FIG. 2 shows the surface of this film, but the surface was smooth and no fine irregularities were formed.

[0023]

According to the present invention, a solution of a palladium salt is applied to the surface of an aromatic polyimide film obtained from an aromatic tetracarboxylic acid component and an aromatic diamine component or an aromatic polyamic acid film as a precursor thereof. , 300
The present invention relates to the production of a roughened aromatic polyimide film characterized by having fine irregularities on the film surface when heated at a temperature of at least ° C. The surface-roughened aromatic polyimide film of the present invention has irregularities on the surface, so that the aromatic polyimide film maintains the excellent heat resistance and the like inherently at a high level for easy sliding and adhesion. It is useful as a base film having excellent properties.

[Brief description of the drawings]

FIG. 1 is a sectional view of an aromatic polyimide film for explaining one embodiment of the present invention.

FIG. 2 is a cross-sectional view of an aromatic polyimide film for explaining an example of a comparative example.

[Explanation of symbols]

 Reference Signs List 1 aromatic polyimide film 2 cross section of aromatic polyimide film 3 concave portion of aromatic polyimide film 4 convex portion of aromatic polyimide film 5 smooth portion of aromatic polyimide film

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 27/00-27/42 C08J 7/04

Claims (1)

(57) [Claims] 1. A solution of a palladium salt is applied to the surface of an aromatic polyimide film or a precursor (aromatic polyamic acid) film obtained from an aromatic tetracarboxylic acid component and an aromatic diamine component, and then coated at 300 ° C. A method for producing a roughened polyimide film, characterized by heating at a temperature of C or higher.