JP2005075949A - Method for manufacturing polyimide resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide resin with reduced ion level such as sodium, potassium, calcium, magnesium and chlorine ions. <P>SOLUTION: This method for manufacturing the solid polyimide resin comprises addition of a varnish of the polyimide resin into water, wherein the total contents of sodium, potassium, calcium, magnesium and chlorine in water are ≤80 ppm, preferably furthermore an acid the pKa of which is less than 7 is added. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a polyimide resin. More specifically, the present invention relates to a method for producing a polyimide resin having a low content of alkali metal, alkaline earth metal and halogen. This polyimide resin is useful as a film, coating material, and adhesive. More specifically, it is excellent in heat resistance, abrasion resistance, slipperiness, and electrical insulation, and is a lubricant, chemical resistant paint, magnetic tape, flexible. Provided is a polyimide resin useful for a disk, a back transfer material of a thermal transfer ribbon, an interlayer insulating material of an electronic material, and the like.

Conventionally, a polyimide resin is polymerized with a high boiling polar solvent such as N-methyl-2-pyrrolidone or dimethylacetamide. The polymerized product is in a state dissolved in these high-boiling solvents. When a solid resin is required, it is solidified in water and dried to obtain a solid resin. Moreover, when changing the high boiling polar solvent used for superposition | polymerization to another solvent, the said solid resin is melt | dissolved in the solvent different from the time of superposition | polymerization, and a varnish is obtained (for example, refer patent document 1).
Japanese Patent Laid-Open No. 7-126386 (Example 1 and others)

  Water is used to obtain a solid resin, but water contains ions such as sodium, potassium, calcium, magnesium, and chlorine, which are mixed into the resin. It has been found that mixing these ions has various adverse effects. For example, when used as an interlayer insulating film of electronic materials, the insulation properties deteriorate, and when used as a chemical-resistant can paint, the above ions migrate to the contents of the can, and at the same time the adhesion with the can deteriorates and peels off in the worst case When applied to a metal as a lubricating coating, corrosion at the interface between the metal and the coating is accelerated by the above ions and peels off in the worst case. When used as a backcoat layer for a thermal transfer ribbon of a printer, the head in contact with the backcoat layer There arises a problem that the ions promote corrosion and, in the worst case, printing cannot be performed. For this reason, the removal of the ions has been a very important issue for solving various problems.

  In order to solve these problems, the present inventors have intensively studied, and as a result, have reached the present invention. That is, this invention is the manufacturing method of the following polyimide resin.

(1) In the production method of obtaining a solid polyimide resin by adding a polyimide resin varnish to water, the sum of the contents of sodium, potassium, calcium, magnesium and chlorine in water is 80 ppm or less. A method for producing a polyimide resin.

(2) The method for producing a polyimide resin according to (1), wherein an acid is further added.

(3) The method for producing a polyimide resin according to (2), wherein the pKa of the acid is smaller than 7.

(4) The method for producing a polyimide resin according to (2) or (3), wherein the molecular formula of the acid does not include sodium, potassium, calcium, magnesium and chlorine.

(5) The varnish is a polyimide resin varnish polymerized using a catalyst containing an alkali metal, an alkaline earth metal, or a halogen in the molecular formula, wherein the varnish is any one of (1) to (4) Manufacturing method of polyimide resin.

(6) The method for producing a polyimide resin according to any one of (1) to (5), wherein the polyimide resin is a polyamideimide resin.

(7) The polyamideimide resin has a glass transition temperature of 120 ° C. or more, a logarithmic viscosity of 0.1 dl / g or more, and an amine residue contains 4,4′-dicyclohexylmethane and / or isophorone ( 6) The manufacturing method of the polyimide resin of description.

  The present invention makes it possible to produce a polyimide resin having a low content of alkali metals, alkaline earth metals, and halogens. This polyimide resin is useful as a film, coating material, and adhesive. More specifically, it is excellent in heat resistance, abrasion resistance, slipperiness, and electrical insulation, and is a lubricant, chemical resistant paint, magnetic tape, flexible. A polyimide resin useful for a disk, a back transfer material of a thermal transfer ribbon, an interlayer insulating material of an electronic material, and the like can be provided.

  The polyimide resin used in the present invention refers to a resin having an imide ring as a repeating unit in the resin skeleton, and examples thereof include polyamideimide, polyesterimide, polyetherimide, and maleimide in addition to polyimide. The production method is a known method such as an isocyanate method produced from an acid component and an isocyanate (amine) component, an acid chloride method produced from an acid chloride (acid component) and an amine, or a direct method produced from an acid component and an amine component. Manufactured.

  When the polyimide resin of the present invention is produced by an isocyanate method, it is produced from the following acid component and isocyanate component. Acid components include trimellitic anhydride, ethylene glycol bisanhydro trimellitate, propylene glycol bis anhydro trimellitate, 1,4-butanediol bis anhydro trimellitate, hexamethylene glycol bis anhydro trimellitate. Tate, polyethylene glycol bisanhydro trimellitate, alkylene glycol bis anhydro trimellitate such as polypropylene glycol bis anhydro trimellitate, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, 3,3'-4, 4'-diphenylsulfonetetracarboxylic anhydride, 3,3'-4,4'-diphenyltetracarboxylic anhydride, 4,4'-oxyphthalic anhydride, terephthalic acid, isophthalic acid, 4,4'-biphenyl Dicarboxylic 4,4′-biphenyl ether dicarboxylic acid, 4,4′-benzophenone dicarboxylic acid, pyromellitic acid, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid, 3,3 ′, 4,4′-biphenyl Examples include sulfonetetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, maleic acid, fumaric acid, dimer acid, and stilbene dicarboxylic acid. These acid components can be used alone or in combination. As these acid components, trimellitic acid anhydride, pyromellitic acid anhydride, and cyclohexanedicarboxylic acid are preferable from the viewpoint of reactivity, heat resistance, and cost. More preferred are trimellitic acid and a copolymer of trimellitic acid and cyclohexanedicarboxylic acid. The copolymerization amount is preferably from 80 mol% to 20 mol% in trimellitic acid and from 20 mol% to 80 mol% in cyclohexanedicarboxylic acid from the viewpoints of heat resistance, transparency and solubility. When the content of trimellitic anhydride exceeds 80 mol%, the solubility in alcohol solvents decreases, and amide solvents such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and γ-butyrolactone This is because such high-boiling solvents will not dissolve unless used together.

  As the isocyanate component, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane-4,4′-diisocyanate 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 3,3′-diethyldiphenylmethane-4,4′-diisocyanate, 3,3′-dichlorodiphenylmethane-4,4′-diisocyanate, 3,3 ′ -Dichlorodiphenyl-4,4'-diisocyanate, 4,4'-diisocyanate-3,3'-dimethylbiphenyl, hexamethylene diisocyanate, isophorone diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate Over doors and the like. Among these isocyanate components, diphenylmethane-4,4′-diisocyanate, dicyclohexylmethane-4,4′-diisocyanate and isophorone diisocyanate are preferable from the viewpoint of solubility and heat resistance, and more preferably isophorone diisocyanate and dicyclohexylmethane-4. , 4'-diisocyanate.

  The polyimide resin of the present invention is produced from the above-mentioned acid, isocyanate (or amine), but if necessary, at the end of polyether, polyester, polyacrylonitrile = butadiene copolymer, polybutadiene, polycarbonate diol, polydimethylsiloxane, etc. A component having a functional group may be copolymerized.

  In the polyimide resin of the present invention, a functional group having reactivity at the terminal, for example, a carbon-carbon double bond, an epoxy group, an isocyanate group, a cyanate group, a carboxylic acid, a hydroxyl group, and a thiol can be introduced.

  As the amine component when the polyimide resin used in the present invention is produced by the acid chloride method or the direct method, 4,4′-diaminodicyclohexylmethane, 1,3-cyclohexanebis (methylamine), o-chloropara Phenylenediamine, p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 3,4 ′ -Diaminodiphenylsulfone, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 2,2'-bis (aminophenyl) propane, 2,4-tolylenediamine, 2,6-tolylenediamine, p -Xylerin diamine, isophorone diamine, hexa Ethylenediamine, p- phenylenediamine, m- phenylenediamine, and the like.

  The logarithmic viscosity of the polyimide resin of the present invention is from 0.1 dl / g to 2.0 dl / g, preferably from 0.2 dl / g to 1.8 dl / g. When the logarithmic viscosity is 0.1 dl / g or less, the coating film is brittle and the wear resistance is not sufficiently exhibited. Moreover, if it is 2.0 dl / g or more, the viscosity of a varnish will become high and handling will become difficult.

  Examples of the solvent used for the synthesis of the polyimide resin used in the present invention include amide solvents such as dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone and dimethylimidazolidinone, nitro solvents such as nitrobenzene, Examples include urea-based solvents such as dimethylurea, sulfur-based solvents such as dimethylsulfoxide, and ester-based solvents such as γ-butyrolactone, but dimethylimidazolidinone and γ-butyrolactone from the viewpoint that there are few side reactions. N-methyl-2-pyrrolidone alone or a mixed solvent is preferred. More preferred are γ-butyrolactone and N-methyl-2-pyrrolidone.

  The polyimide resin of the present invention is synthesized by stirring at 50 to 230 ° C., preferably 80 to 200 ° C. in the above solvent, but in order to accelerate the reaction, triethylamine, lutidine, picoline, undecene, triethyldiamine, etc. Amines, lithium methylates, sodium methylates, sodium ethylates, potassium butoxides, potassium fluorides, sodium fluorides and other alkali metals, alkaline earth metal compounds or metals such as cobalt, tin and zinc, metalloids The reaction may be performed in the presence of a catalyst such as a compound. Those having an alkali metal or halogen in the molecular formula such as potassium fluoride or sodium methylate are preferred because of high catalytic activity.

  The polyimide resin varnish synthesized in this way and a varnish composed of a high boiling point solvent are added to water to obtain a solid polyimide resin.

  In order to effectively elute the high boiling polar solvent from the polyimide resin varnish and to adjust the elution rate, an additive may be added to the polyimide resin varnish and water. For example, alcohol solvents such as ethylene glycol and triethylene glycol, hydrocarbon solvents such as toluene and xylene, ketone solvents such as acetone and methyl ethyl ketone, ether solvents such as dioxane and ethylene glycol dimethyl ether, methyl acetate and ethyl acetate Ester solvent.

  The sum of the contents of sodium, potassium, calcium, magnesium and chlorine in the water used is 80 ppm or less, preferably 60 ppm or less, more preferably 40 ppm or less, and most preferably 20 ppm or less. If the sum of the contents of sodium, potassium, calcium, magnesium, and chlorine is 81 ppm or more, there is a problem of deteriorating properties such as resin electrical insulation, migration resistance, and adhesion to metal.

  Further, an acid can be further added. By adding an acid, there is an effect of reducing the content of sodium, potassium, calcium, and magnesium in the resin. This is because the proton at the end of the polyimide resin exchanges with each cation to form a salt, and by adding an acid, ion exchange with this salt occurs, and metal ions such as sodium, potassium, calcium, and magnesium This is because it can be removed. The pKa of the acid used is less than 7, preferably less than 6, and more preferably less than 5. If pKa exceeds 7, the above ion exchange may be difficult and metal ions may not be removed.

  Examples of the acid include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as formic acid, acetic acid, propionic acid, oxalic acid, succinic acid, and citric acid. Preferred are acids that do not contain metal ions and halide ions in the molecular formula, more preferred are organic acids, and most preferred are formic acid, acetic acid, and citric acid. Further, the amount of acid added is 10% or less, preferably 7% or less, more preferably 5% or less, and most preferably 1% or less with respect to water. The lower limit is preferably 0.0001% or more. When the addition amount exceeds 10%, the residual amount increases in the polyimide resin, and mechanical properties such as elastic modulus and elongation are impaired.

  Furthermore, elution of the high boiling polar solvent can be further accelerated by lowering the resin concentration of the resin varnish and increasing the temperature of the coagulation bath. The polymer concentration is usually 5 to 80% by weight, preferably 10 to 60%, more preferably 15 to 50%.

  The method of charging the resin varnish into the coagulation bath is not particularly limited, but for continuous and efficient production, (1) a method of discharging from a fine nozzle and putting it in water, (2) a base such as PET film or metal foil A method of applying the varnish to the material and then putting it in water is preferred. In the case of (1), the pore nozzle diameter is preferably 10 mm or less, more preferably 5 mm or less, and most preferably 3 mm or less. If the pore nozzle diameter exceeds 10 mm, the contact area between the resin and water when solidified is small, and the removal efficiency of the high-boiling solvent becomes poor. In the case of (2), the coating thickness of the resin varnish is preferably 5 mm or less, more preferably 4 mm or less, and most preferably 3 mm or less. If it exceeds 5 mm, the contact area between the resin and water when solidified is small, and the removal efficiency of the high-boiling solvent is deteriorated. In the case of (2), the solidified resin may be peeled off from the base material, or may be used without being peeled off.

  The reprecipitated resin is separated into water and resin by a method such as filtration. The resin is preferably further washed with water to remove the high boiling point solvent. For washing, a solvent (poor solvent) that dissolves a high-boiling solvent other than water and does not dissolve the resin may be used. Moreover, you may add an acid to the solvent used for washing | cleaning.

  There is no particular limitation on the amount of solvent used for cleaning. Further, when removing the high boiling point solvent, it is preferable to increase the number of times of cleaning if the amount of the cleaning solvent is constant. Further, it is preferable to remove water adhering to the resin before washing or a mixture of a poor solvent and a high-boiling solvent by blowing off with a centrifugal dehydrator or compressed air. The resin is then dried. Drying can be performed by a normal method such as hot air drying, vacuum drying, or drying with dry air.

  Although the usage method of the polyimide-type resin produced with this manufacturing method is not specifically limited, A solid state, the state dissolved in the solvent, etc. can be used. When dissolving in a solvent, the solvent used for dissolution is not particularly limited. For example, alcohol solvents such as methanol, etal and propanol, ether solvents such as diethyl ether and tetrahydrofuran, ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone, aromatic solvents such as toluene and xylene, carbonization such as hexane and cyclohexane A hydrogen-based solvent may be used, and a single solvent or a mixture of two or more solvents may be used. Moreover, the boiling point of the solvent is preferably 200 ° C. or less, more preferably 180 ° C. or less, and most preferably 150 ° C. or less, from the viewpoint of the drying property of the coating film.

  There is no particular limitation on the means for redissolving, and it can be dissolved by an ordinary method. For example, a solvent is put into a container, and a dry polymer is added little by little at room temperature or under heating while stirring.

  Add organic or inorganic lubricant to the polyimide resin of the present invention, polyester resin, polyamide resin, polyurethane resin, acrylic resin, melamine resin, phenol resin, epoxy resin, polyfunctional isocyanate and other resins and curing agents, silicon Oils, higher fatty acids, waxes, surfactants, inorganic particles such as silica and alumina, colorants and the like may be blended.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not restrict | limited by these Examples.

The characteristics shown in the examples are measured and evaluated by the following methods.
Logarithmic viscosity;
A solution obtained by dissolving 0.5 g of a polymer in 100 ml of N-methyl-2-pyrrolidone was measured at 25 ° C. using an Ubbelohde viscosity tube.
Solution viscosity;
The measurement was made at 25 ° C. using a TOKIMEC BL viscometer.
Amount of ionic impurities;
[Preparation of cation measurement sample]
When the measurement sample was water, hydrochloric acid was added to the water to be measured to prepare a 1.2 mol / l hydrochloric acid solution. When the measurement sample was a polyimide resin, the resin varnish was placed in a crucible, burned and incinerated, and then dissolved in a 1.2 mol / l hydrochloric acid aqueous solution.
[Adjustment of chloride ion measurement sample]
When the measurement sample was water, it was measured as it was. When the measurement sample was varnish, a mixed aqueous solution of varnish, oxygen, potassium carbonate and sodium hydrogen carbonate was put into the flask and burned in the flask, and then the mixed aqueous solution of potassium carbonate and sodium hydrogen carbonate in the flask was measured.
[Measuring method]
Sodium ions and potassium ions were measured using an atomic absorption photometer (AA-640-12, manufactured by Shimadzu Corporation). Calcium and magnesium were measured using a high frequency coupled plasma emission analysis (ICPS-2000, manufactured by Shimadzu Corporation). Chloride ions were measured using ion chromatography (Dionex DX-120, manufactured by Nippon Dionex Co., Ltd.), with AG12A and AS12A in the column, and 2.7 mmol / l sodium carbonate and 0.3 mmol / l sodium bicarbonate in the eluent. It measured using the liquid.

Synthesis Example 1 Production of Polyimide Resin Varnish 0.5 mol of trimellitic anhydride, 0.5 mol of cyclohexanedicarboxylic acid, 0.97 mol of isophorone diisocyanate, 0.02 mol of potassium fluoride together with γ-butyrolactone in a reaction vessel The monomer concentration was 50% by weight. This solution was reacted at 100 ° C. for 2 hours with stirring, and further reacted at 180 ° C. for 3 hours. The solution was cooled to room temperature while diluted to about 30% with N-methyl-2-pyrrolidone. The obtained sample had a solution viscosity of 70 dPa · s, a logarithmic viscosity of 0.25 dl / g, and the appearance was light yellow and transparent.

Example 1
Using ion-exchanged water as water, the polyimide resin varnish obtained in Synthesis Example 1 was added to water in the form of a thread having a diameter of about 1 mm to solidify the polyimide resin. The quantity ratio is 1 part of polyimide resin varnish with respect to 3 parts of ion-exchanged water. The coagulated resin was further washed four times with 3 parts of the same amount of ion-exchanged water and then dried at 100 ° C. for 12 hours to obtain a polyimide resin. Table 1 shows the ion exchange water and the amount of ions of the polyimide resin used.

Example 2
The same as Example 1, except that 0.0001 part of acetic acid (pKa = 4.7) was added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Example 3
Example 1 is the same as Example 1 except that 0.001 part of acetic acid is added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Example 4
The same as Example 1 except that 0.01 part of acetic acid was added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Example 5
The same as Example 1, except that 0.0001 part of citric acid is added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Example 6
Example 1 is the same as Example 1 except that 0.001 part of citric acid is added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Example 7
The same as Example 1, except that 0.01 part of citric acid (pKa = 3.1) was added to 1 part of ion-exchanged water of Example 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Comparative Example 1
Example 1 is the same as Example 1 except that the ion-exchanged water in Example 1 is changed to tap water 1. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

Comparative Example 2
Example 1 is the same as Example 1 except that the ion-exchanged water in Example 1 is changed to tap water 2 and the number of washings is changed to 3. Table 1 shows the ion content of ion-exchanged water, and Table 2 shows the ion content of the obtained polyimide resin.

  The present invention makes it possible to produce a polyimide resin having a low content of alkali metals, alkaline earth metals, and halogens. This polyimide resin is useful as a film, coating material, and adhesive. More specifically, it is excellent in heat resistance, abrasion resistance, slipperiness, and electrical insulation, and is a lubricant, chemical resistant paint, magnetic tape, flexible. A polyimide resin useful for a disk, a back transfer material of a thermal transfer ribbon, an interlayer insulating material of an electronic material, and the like can be provided.

Claims (7)

  In the production method of obtaining a solid polyimide resin by adding a polyimide resin varnish to water, the total content of sodium, potassium, calcium, magnesium and chlorine in water is 80 ppm or less. Manufacturing method of resin.   Furthermore, an acid is added, The manufacturing method of the polyimide resin of Claim 1 characterized by the above-mentioned.   3. The method for producing a polyimide resin according to claim 2, wherein the pKa of the acid is less than 7.   The method for producing a polyimide resin according to claim 2 or 3, wherein the molecular formula of the acid does not include sodium, potassium, calcium, magnesium and chlorine.   The production of a polyimide resin according to any one of claims 1 to 4, wherein the varnish is a polyimide resin varnish polymerized using a catalyst containing an alkali metal, an alkaline earth metal, and a halogen in the molecular formula. Method.   The method for producing a polyimide resin according to claim 1, wherein the polyimide resin is a polyamideimide resin.   7. The polyamideimide resin has a glass transition temperature of 120 ° C. or higher, a logarithmic viscosity of 0.1 dl / g or higher, and an amine residue contains 4,4′-dicyclohexylmethane and / or isophorone. Manufacturing method of polyimide resin.