JP5499555B2 - Polyimide film and method for producing polyimide film - Google Patents

Description

  The present invention relates to a polyimide film excellent in adhesiveness. Moreover, this invention relates to the manufacturing method of the polyimide film which can improve the adhesiveness of a polyimide film by a simple method.

  Polyimide films are widely used in the fields of electric / electronic devices and semiconductors because they are excellent in heat resistance, chemical resistance, mechanical strength, electrical properties, dimensional stability, and the like. For example, as a flexible printed wiring board (FPC), a copper-clad laminated board formed by laminating a copper foil on one or both sides of a polyimide film is used.

  As a polyimide film suitable as an FPC film or the like, for example, an aromatic tetracarboxylic acid component having 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride as a main component and paraphenylenediamine as a main component. There is a polyimide film produced by thermal imidization from an aromatic diamine component (Patent Document 1, etc.).

  However, polyimide films generally have problems with adhesion, and when bonded to a metal foil such as a copper foil via a heat-resistant adhesive such as an epoxy resin adhesive, a laminate having sufficient peel strength is obtained. It may not be possible.

  For example, in the polyimide film described in Patent Document 1, by applying a surface treatment liquid containing a heat-resistant surface treatment agent (coupling agent) to the surface of the self-supporting film (solidified film) of the polyimide precursor solution, The adhesion of polyimide film is improved. Thus, the polyimide film which has the outstanding adhesiveness which does not need to apply | coat a coupling agent is calculated | required.

  An alkali treatment has also been proposed as a method for improving the adhesion of the polyimide film. For example, in Patent Document 2, as a polyimide film on which a metal foil can be bonded with high adhesion by a polyimide-based adhesive, an alkaline aqueous solution containing a permanganate and a hydroxide such as potassium hydroxide or sodium hydroxide is used. A surface treated polyimide film is disclosed.

  By the way, Patent Document 3 discloses a reaction between biphenyltetracarboxylic dianhydride and an aromatic diamine in which two amino groups are located at a meta position as a colorless and transparent polyimide molded body used for a liquid crystal alignment film or the like. For example, a polyimide film obtained by reaction of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride with 2,4-toluenediamine.

  In Patent Document 4, as a polyimide used for a liquid crystal alignment film of a liquid crystal display element, 81 to 51 mol% of a recurring unit derived from an aromatic tetracarboxylic dianhydride and an aromatic tetranuclear diamine is used. 1 to 4 mol% of repeating units derived from carboxylic dianhydride and diaminosiloxane, and 18 to 45 mol% of repeating units derived from aromatic tetracarboxylic dianhydride and 2,4-toluenediamine Solvent-soluble polyimides are disclosed, and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride is mentioned as an aromatic tetracarboxylic dianhydride.

  Further, in Patent Document 5, in order to remove the catalyst compound and the solvent remaining in the film, a film obtained by casting using a solution containing a polyamic acid and a catalyst compound, A method for producing a polyimide film is disclosed in which the film is dried after being immersed in water preferably at 5 ° C to 100 ° C for 30 minutes to 100 hours.

Japanese Patent Publication No.6-2828 JP 2007-9186 A Japanese Patent Laid-Open No. 62-13436 JP-A-61-240223 Japanese Patent Laid-Open No. 2006-56956

  An object of the present invention is to provide a polyimide film that retains the excellent properties of a polyimide film and also has excellent adhesion, and in particular, in a polyimide film having a specific composition that has excellent adhesion, It is to provide a polyimide film further improved by a simple method.

  In particular, it is to provide a polyimide film in which the adhesion of a polyimide film that can be used for a substrate or a cover material used for a wiring board is further improved by a simple method.

  The present invention relates to the following matters.

1. A polyimide film obtained by reacting a tetracarboxylic acid component with a diamine component containing a diamine represented by the following general formula (1),
A polyimide film characterized by being surface-treated by spraying water on the surface.

（式中、Ｒは炭素数１〜４の直鎖または分岐アルキル基を表し、ｎは１〜４の整数を表す。ただし、ｎが２以上の場合には、複数個のＲは同一でも異なっていてもよい。）
２． 前記一般式（１）で表されるジアミンが、２，４−トルエンジアミンおよび／または２，６−トルエンジアミンであることを特徴とする上記１記載のポリイミドフィルム。

(In the formula, R represents a linear or branched alkyl group having 1 to 4 carbon atoms, and n represents an integer of 1 to 4. However, when n is 2 or more, plural Rs may be the same or different. May be.)
2. 2. The polyimide film as described in 1 above, wherein the diamine represented by the general formula (1) is 2,4-toluenediamine and / or 2,6-toluenediamine.

  3. 3. The polyimide film as described in 1 or 2 above, wherein the diamine represented by the general formula (1) is contained in a range of 3 mol% or more and less than 35 mol% in 100 mol% of the diamine component.

  4). The said tetracarboxylic acid component contains 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and / or pyromellitic dianhydride, The said any one of 1-3 characterized by the above-mentioned. Polyimide film.

  5. The polyimide film as described in any one of 1 to 4 above, wherein the diamine component further contains paraphenylenediamine and / or diaminodiphenyl ethers.

6). The tetracarboxylic acid component contains 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and / or pyromellitic dianhydride as a main component,
The diamine component contains paraphenylenediamine and / or diaminodiphenyl ether as a main component, and further contains a diamine represented by the general formula (1) in a range of 3 mol% or more and less than 35 mol%. The polyimide film according to any one of 1 to 5 above.

  7). The adhesive lamination polyimide film formed by laminating | stacking an adhesive bond layer on the surface which sprayed the water of the polyimide film in any one of said 1-6, and was surface-treated.

8). A polyamic acid or polyimide solution obtained by reacting a tetracarboxylic acid component with a diamine component containing the diamine represented by the general formula (1) is cast on a support, and dried to self-support. Obtaining a conductive film;
Heating the self-supporting film to obtain a polyimide film;
The manufacturing method of the polyimide film which has the process of spraying water on the surface of the obtained polyimide film.

  In the present invention, water is sprayed on the surface of a polyimide film obtained by reacting a tetracarboxylic acid component with a diamine represented by the general formula (1), preferably a diamine component containing 2,4-toluenediamine. Surface treatment (spray treatment). This treatment further improves the adhesion of the polyimide film. Further, not only in the initial stage (before heat treatment) but also the adhesion after heat treatment, for example, the adhesion after heat treatment at 150 ° C. for 24 hours is improved. The polyimide film of the present invention is excellent in adhesiveness with an adhesive, and particularly excellent in adhesiveness with an epoxy-based or acrylic adhesive.

  Tetracarboxylic acid component containing 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and / or pyromellitic dianhydride as main components, and paraphenylenediamine and / or diaminodiphenyl ethers as main components The polyimide film obtained from the diamine component contained is excellent in heat resistance and mechanical properties, and therefore is used as various base materials. When a diamine component further containing a diamine represented by the general formula (1), preferably 2,4-toluenediamine, preferably in a range of 3 mol% or more and less than 35 mol% is used as the diamine component. The polyimide film obtained is further improved in adhesiveness with an adhesive or the like while maintaining the above characteristics. In the case of a modified polyimide film obtained by using such a diamine component containing the diamine represented by the general formula (1), the surface is sprayed to spray water on the surface thereof. Further, the adhesion of the polyimide film is improved. Further, not only in the initial stage (before heat treatment) but also the adhesion after heat treatment, for example, the adhesion after heat treatment at 150 ° C. for 24 hours is improved. The polyimide film of the present invention is excellent in adhesiveness with an adhesive, and particularly excellent in adhesiveness with an epoxy-based or acrylic adhesive.

  As described above, conventionally, alkali treatment has been performed to improve the adhesion of the polyimide film. In the case of alkali treatment, if metal ions remain, the electrical insulation properties may decrease. Therefore, after treating the polyimide film surface with an alkaline aqueous solution, it is usually treated with water, acid and water (water washing, pickling, It is necessary to remove the metal ions remaining in the film or on the surface by washing with water. On the other hand, in this invention, after processing the polyimide film surface with water, a polyimide film can be dried as it is, without post-processing. According to the present invention, a polyimide film excellent in adhesiveness can be obtained with a small number of steps, and the productivity is also excellent.

  The polyimide film used in the present invention is obtained by reacting a tetracarboxylic acid component with a diamine component containing the diamine represented by the general formula (1) by a known method, for example, by thermal imidization and / or chemical imidization. It is obtained. In 100 mol% of the diamine component, the content of the diamine represented by the general formula (1) is not particularly limited, but is preferably 3 mol% or more and less than 35 mol%, preferably 5 mol% to 5 mol%. It is more preferably 30 mol%, and particularly preferably 7 mol% to 25 mol%.

  When the polyimide film of the present invention contains a plurality of tetracarboxylic acid components and diamine components, they may be randomly copolymerized, block copolymerized, or these may be used in combination.

  The tetracarboxylic acid component preferably contains 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and / or pyromellitic dianhydride as a main component, and the diamine component is paraphenylenediamine. And / or a diaminodiphenyl ether as a main component and further containing a diamine represented by the general formula (1) in a range of preferably 3 mol% or more and less than 35 mol%. When such a tetracarboxylic acid component and a diamine component are used, it is easy to obtain a film having excellent mechanical properties, it can be suitably used for various substrates such as a wiring substrate, and the productivity is also excellent. In particular, the tetracarboxylic acid component preferably includes 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride as a main component, and the diamine component preferably includes paraphenylenediamine as a main component.

  In the general formula (1), R represents a linear or branched alkyl group having 1 to 4 carbon atoms. When n is 2 or more, the plurality of R may be the same or different. R is preferably a methyl group or an ethyl group, and particularly preferably a methyl group.

  n represents an integer of 1 to 4, preferably 1 or 2, and particularly preferably 1.

Examples of the diamine represented by general formula (1), 2,4-toluene diamine, 2, 6-toluenediamine, 1-ethyl-2,4-Jiaminobenze emissions, etc. can be mentioned, 2,4 -Toluenediamine is particularly preferred. By using toluenediamine, particularly preferably 2,4-toluenediamine, a polyimide film having better adhesiveness can be obtained. Furthermore, it can be expected that the water vapor permeability of the obtained polyimide film is improved and the coloring is reduced.

  The diamine represented by the general formula (1) may be used alone or in combination of two or more.

  3 mol% or more is preferable, as for content of the diamine represented by the said General formula (1) in a diamine component, 5 mol% or more is more preferable, and 7 mol% or more is further more preferable. In addition, the content of the diamine represented by the general formula (1) in the diamine component is preferably less than 35 mol%, more preferably 30 mol% or less, and even more preferably 25 mol% or less. If content of the diamine represented by the said General formula (1) in a diamine component is in the said range, the adhesiveness of the polyimide film obtained will improve more. On the other hand, if the content of the diamine represented by the general formula (1) in the diamine component exceeds the above range, the properties of the resulting polyimide film may be deteriorated.

As a method for producing the polyimide film of the present invention,
(1) A polyamic acid solution, or a polyamic acid solution composition in which an imidization catalyst, a dehydrating agent, a release aid, inorganic fine particles and the like are selected and added to a polyamic acid solution as necessary on a support in the form of a film Casting, heat drying to obtain a self-supporting film, then thermally dehydrating and desolvating to obtain a polyimide film,
(2) A cyclization catalyst and a dehydrating agent are added to the polyamic acid solution, and the polyamic acid solution composition added by selecting inorganic fine particles and the like as necessary is cast on a support in a film form. A method of obtaining a polyimide film by dehydrating and cyclizing and obtaining a self-supporting film by heating and drying as necessary, followed by heat desolvation and imidization can be mentioned.

  The polyimide film of this invention can be manufactured as follows as an example. First, the polycarboxylic acid which is a polyimide precursor is synthesize | combined by making the tetracarboxylic-acid component and the diamine component containing the diamine represented by the said General formula (1) react in an organic solvent. If necessary, an imidization catalyst, a dehydrating agent, a mold release aid, inorganic fine particles and the like may be added.

  Next, the obtained polyamic acid solution is cast on a support, heated and dried to produce a self-supporting film. And a polyimide film can be manufactured by heating and imidating this self-supporting film. Alternatively, the tetracarboxylic acid component and the diamine component are reacted in an organic solvent to synthesize a polyimide soluble in the organic solvent, and the obtained polyimide solution can be used for the production of a self-supporting film.

  Specific examples of tetracarboxylic dianhydride include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA) and pyromellitic dianhydride (PMDA). 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride (a-BPDA), oxydiphthalic dianhydride, diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride, Bis (3,4-dicarboxyphenyl) sulfide dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 2 , 3,3 ′, 4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, p-phenylenebis (trimellitic acid monoester acid anhydride), p-biphenylenebis (trimellitic acid monoester acid anhydride), m -Terphenyl-3,4,3 ', 4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3', 4'-tetracarboxylic dianhydride, 1,3-bis (3 , 4-dicarboxyphenoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) benzene dianhydride, 1,4-bis (3,4-dicarboxyphenoxy) biphenyl dianhydride, 2,2-bis [(3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracathe Bon dianhydride, 4,4 '- (2,2-hexafluoroisopropylidene) diphthalic dianhydride, and the like. These may be used alone or in combination of two or more. The tetracarboxylic dianhydride to be used can be appropriately selected according to desired characteristics.

  As the tetracarboxylic acid component, an acid component selected from s-BPDA and PMDA, preferably s-BPDA, in 50 mol% or more, more preferably 70 mol% or more, particularly preferably in 100 mol% of the acid component. A tetracarboxylic acid component containing 75 mol% or more is preferable because the resulting polyimide film is excellent in mechanical properties.

As specific examples of diamines other than the diamine represented by the general formula (1),
1) One benzene nucleus diamine such as paraphenylenediamine (1,4-diaminobenzene; PPD), 1,3-diaminobenzene,
2) Diaminodiphenyl ethers such as 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 3,3′-dimethyl-4,4 ′ -Diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4 ' -Diaminodiphenylmethane, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane, 3,3 ', 5,5'-tetramethyl-4,4'-diaminodiphenylmethane, bis (4-aminophenyl) sulfide, 4,4'-diaminobenzanilide, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine, 2,2'-dimethylbenzene Dizine, 3,3'-dimethoxybenzidine, 2,2'-dimethoxybenzidine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide 3,4′-diaminodiphenylsulfide, 4,4′-diaminodiphenylsulfide, 3,3′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,3 ′ -Diaminobenzophenone, 3,3'-diamino-4,4'-dichlorobenzophenone, 3,3'-diamino-4,4'-dimethoxybenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 2,2-bis (3- Minophenyl) propane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 2,2-bis (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 3,3′-diaminodiphenyl sulfoxide, 3,4′-diaminodiphenyl sulfoxide, 4,4′-diaminodiphenyl sulfoxide, etc. The benzene core of two diamines,
3) 1,3-bis (3-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (3-aminophenyl) benzene, 1,4-bis (4-amino) Phenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (3 -Aminophenoxy) -4-trifluoromethylbenzene, 3,3'-diamino-4- (4-phenyl) phenoxybenzophenone, 3,3'-diamino-4,4'-di (4-phenylphenoxy) benzophenone, 1,3-bis (3-aminophenyl sulfide) benzene, 1,3-bis (4-aminophenyl sulfide) benzene, 1,4-bis (4-aminophenyls) Fido) benzene, 1,3-bis (3-aminophenylsulfone) benzene, 1,3-bis (4-aminophenylsulfone) benzene, 1,4-bis (4-aminophenylsulfone) benzene, 1,3- Bis [2- (4-aminophenyl) isopropyl] benzene, 1,4-bis [2- (3-aminophenyl) isopropyl] benzene, 1,4-bis [2- (4-aminophenyl) isopropyl] benzene, etc. The benzene core of three diamines,
4) 3,3′-bis (3-aminophenoxy) biphenyl, 3,3′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, bis [3- (3-aminophenoxy) phenyl] ether, bis [3- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, Bis [4- (4-aminophenoxy) phenyl] ether, bis [3- (3-aminophenoxy) phenyl] ketone, bis [3- (4-aminophenoxy) phenyl] ketone, bis [4- (3-amino Phenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone, bis [3- (3-aminophenoxy) phenyl] Sulfide, bis [3- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [3- (3 -Aminophenoxy) phenyl] sulfone, bis [3- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, Bis [3- (3-aminophenoxy) phenyl] methane, bis [3- (4-aminophenoxy) phenyl] methane, bis [4- (3-aminophenoxy) phenyl] methane, bis [4- (4-amino Phenoxy) phenyl] methane, 2,2-bis [3- (3-aminophenoxy) phenyl] propane, , 2-bis [3- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl ] Propane, 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [3- (4-aminophenoxy) Phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoro Four diamine diamines such as propane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane,
And so on. These may be used alone or in combination of two or more. The diamine to be used can be appropriately selected according to desired characteristics.

  As the diamine component, a diamine component selected from PPD and diaminodiphenyl ether, preferably PPD, 4,4′-diaminodiphenyl ether, or 100 mol% of the diamine component excluding the diamine represented by the general formula (1), or Polyimide film from which a diamine component containing any one or more of 3,4'-diaminodiphenyl ether, particularly preferably PPD in an amount of 50 mol% or more, more preferably 70 mol% or more, and particularly preferably 75 mol% or more is obtained. Is preferable because of its excellent mechanical properties.

  The synthesis of the polyimide precursor is achieved by random polymerization or block polymerization of approximately equimolar aromatic tetracarboxylic dianhydride and aromatic diamine in an organic solvent. May also be mixed with the reaction conditions was keep two or more polyimide precursors in which either of these two components is excessive, the respective polyimide precursor solution together. The polyimide precursor solution thus obtained can be used for the production of a self-supporting film as it is or after removing or adding a solvent if necessary.

  As an organic solvent of the polyimide precursor solution, a known solvent can be used, for example, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide and the like. Can be mentioned. These organic solvents may be used alone or in combination of two or more.

  If necessary, an imidization catalyst, an organic phosphorus-containing compound, inorganic fine particles, and the like may be added to the polyimide precursor solution as long as it is thermal imidization.

  If necessary, a cyclization catalyst, a dehydrating agent, inorganic fine particles, and the like may be added to the polyimide precursor solution as long as it is chemical imidization.

  Examples of the imidization catalyst include a substituted or unsubstituted nitrogen-containing heterocyclic compound, an N-oxide compound of the nitrogen-containing heterocyclic compound, a substituted or unsubstituted amino acid compound, an aromatic hydrocarbon compound having a hydroxyl group, or an aromatic heterocyclic compound. Cyclic compounds such as 1,2-dimethylimidazole, N-methylimidazole, N-benzyl-2-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 5-methylbenzimidazole and the like. Benzimidazoles such as alkylimidazole and N-benzyl-2-methylimidazole, isoquinoline, 3,5-dimethylpyridine, 3,4-dimethylpyridine, 2,5-dimethylpyridine, 2,4-dimethylpyridine, 4-n- Preferred are substituted pyridines such as propylpyridine It can be used for. The amount of the imidization catalyst used is preferably about 0.01 to 2 times equivalent, particularly about 0.02 to 1 times equivalent to the amic acid unit of the polyamic acid. By using an imidization catalyst, properties of the resulting polyimide film, particularly elongation and end resistance, may be improved.

  Examples of the organic phosphorus-containing compounds include monocaproyl phosphate, monooctyl phosphate, monolauryl phosphate, monomyristyl phosphate, monocetyl phosphate, monostearyl phosphate, triethylene glycol monotridecyl Monophosphate of ether, monophosphate of tetraethylene glycol monolauryl ether, monophosphate of diethylene glycol monostearyl ether, dicaproyl phosphate, dioctyl phosphate, dicapryl phosphate, dilauryl phosphate, dimyristyl phosphate, Dicetyl phosphate, distearyl phosphate, diethylene phosphate of tetraethylene glycol mononeopentyl ether, triethyl Diphosphate of glycol mono tridecyl ether, diphosphate of tetraethyleneglycol monolauryl ether, and phosphoric acid esters such as diphosphate esters of diethylene glycol monostearyl ether, amine salts of these phosphates. As amine, ammonia, monomethylamine, monoethylamine, monopropylamine, monobutylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, monoethanolamine, diethanolamine, triethanolamine Etc.

  Cyclization catalysts include aliphatic tertiary amines such as trimethylamine and triethylenediamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as isoquinoline, pyridine, α-picoline and β-picoline. Etc.

  Examples of the dehydrating agent include aliphatic carboxylic acid anhydrides such as acetic anhydride, propionic anhydride, and butyric anhydride, and aromatic carboxylic acid anhydrides such as benzoic anhydride.

  Inorganic fine particles include fine particle titanium dioxide powder, silicon dioxide (silica) powder, magnesium oxide powder, aluminum oxide (alumina) powder, inorganic oxide powder such as zinc oxide powder, fine particle silicon nitride powder, and titanium nitride powder. Inorganic nitride powder such as silicon carbide powder, inorganic carbide powder such as silicon carbide powder, and inorganic salt powder such as particulate calcium carbonate powder, calcium sulfate powder, and barium sulfate powder. These inorganic fine particles may be used in combination of two or more. In order to uniformly disperse these inorganic fine particles, a means known per se can be applied.

  As an example of the polyimide film of the present invention, the polyimide precursor solution self-supporting film was prepared by adding an polyimide solvent organic solvent solution as described above, or an imidation catalyst, an organic phosphorus-containing compound, inorganic fine particles, and the like. The polyimide precursor solution composition is cast on a support and heated to such a degree that it becomes self-supporting (meaning a stage prior to a normal curing process), for example, can be peeled off from the support. Manufactured.

  The solid content concentration of the polyimide precursor solution used in the present invention is not particularly limited as long as it has a viscosity range suitable for production, but is usually preferably 10% by mass to 30% by mass, and more preferably 15% by mass to 27% by mass. Is more preferable, and 18 mass%-26 mass% is still more preferable.

  The heating temperature and heating time during the production of the self-supporting film can be appropriately determined. In the thermal imidization, for example, the heating may be performed at a temperature of 100 to 180 ° C. for about 1 to 60 minutes.

  The support is not particularly limited as long as it can cast the polyimide precursor solution, but a smooth substrate is preferably used. For example, a metal drum or belt such as stainless steel is used.

  The self-supporting film is not particularly limited as long as the solvent is removed and / or imidized to such an extent that it can be peeled off from the support, but in thermal imidization, the loss on heating is 20 to 50 mass. %, And more preferably, the weight loss by heating is in the range of 20 to 50% by mass and the imidization ratio is in the range of 1 to 55%. In thermal imidization, if the heat loss of the self-supporting film is 20 to 50% by mass and the imidization rate is 1 to 55%, the mechanical properties of the self-supporting film are sufficient.

  Also, if the heating loss of the self-supporting film and the imidization rate are within the above ranges, it is easy to apply the coupling agent solution neatly when applying the coupling agent solution on the upper surface of the self-supporting film. Thus, the occurrence of foaming, cracks, crazes, cracks, cracks, etc. is not observed in the polyimide film obtained after imidization.

  Here, the loss on heating of the self-supporting film is a value obtained by the following equation from the mass W1 of the self-supporting film and the mass W2 of the film after curing.

  Heat loss (mass%) = {(W1-W2) / W1} × 100

  The imidation ratio of the self-supporting film is calculated by measuring the IR spectrum of the self-supporting film and its full-cure product (polyimide film) by the ATR method, and using the ratio of the vibration band peak area or height. be able to. As the vibration band peak, an asymmetric stretching vibration band of an imide carbonyl group, a benzene ring skeleton stretching vibration band, or the like is used. Further, regarding the imidization rate measurement, there is also a method using a Karl Fischer moisture meter described in JP-A-9-316199.

  In the present invention, a solution of a surface treatment agent such as a coupling agent or a chelating agent may be applied to one side or both sides of the self-supporting film thus obtained, if necessary. Even if it is not, usually, the obtained polyimide film is excellent in adhesiveness.

  As surface treatment agents, various coupling agents such as silane coupling agents, borane coupling agents, aluminum coupling agents, aluminum chelating agents, titanate coupling agents, iron coupling agents, copper coupling agents, and chelating agents. Examples thereof include a treatment agent that improves adhesiveness and adhesion of the agent. In particular, it is preferable to use a coupling agent such as a silane coupling agent as the surface treatment agent.

  The surface treatment agent solution can be applied by a known method, for example, gravure coating method, spin coating method, silk screen method, dip coating method, spray coating method, bar coating method, knife coating method, roll coating method. And publicly known coating methods such as blade coating and die coating.

  After applying the surface treating agent solution as necessary, the self-supporting film can be heated and imidized to obtain a polyimide film.

  In the heat treatment for imidation, first, the imidation of the polymer and the evaporation / removal of the solvent are gradually performed at a temperature of about 100 ° C. to 400 ° C. for about 0.05 to 5 hours, particularly 0.1 to 3 hours. Is appropriate. In particular, the heat treatment is stepwise first heat treated at a relatively low temperature of about 100 ° C. to about 170 ° C. for about 0.5-30 minutes, and then at a temperature of 170 ° C.-220 ° C. for about 0.5 ° C. The secondary heat treatment is preferably performed for ˜30 minutes, and then the third heat treatment is performed at a high temperature of 220 ° C. to 400 ° C. for about 0.5 to 30 minutes. If necessary, the fourth high-temperature heat treatment may be performed at a high temperature of 400 ° C to 550 ° C.

  At the time of heat treatment for imidization, in a curing furnace, pin ends, clips, frames, etc. are used to fix at least the edges in the direction perpendicular to the longitudinal direction of the long solid film, that is, the width direction of the film, It is preferable to perform heat treatment by expanding and contracting in the width direction as necessary.

  As the polyimide film of the present invention, a film uniaxially stretched in the MD direction or TD direction can be used, and a film biaxially stretched sequentially or simultaneously in the MD direction and TD direction can also be used.

  The thickness of the polyimide film of the present invention is not particularly limited, but is about 3 to 250 μm, preferably about 4 to 150 μm, more preferably about 5 to 125 μm, and still more preferably about 5 to 100 μm. For example, in the case of a thin polyimide film having a thickness of 12.5 μm or less, low adhesiveness is usually a problem, but according to the present invention, a polyimide film having excellent adhesion even if the thickness is 12.5 μm or less is obtained. Can do.

  In the present invention, surface treatment is performed by spraying water on one or both sides of the polyimide film thus obtained.

  Although the temperature of the water to spray is not specifically limited, It is preferable that it is 5-80 degreeC, It is more preferable that it is 10-60 degreeC, It is especially preferable that it is 15-50 degreeC. When the temperature of water is lower than 5 degreeC, the adhesiveness of the polyimide film obtained may not improve. On the other hand, when the temperature of water is higher than 80 ° C., physical properties of the obtained polyimide film may be lowered.

  The time for spraying water (spray treatment time) can be appropriately selected according to the purpose. The optimum range also depends on the temperature of the sprayed water. Usually, the spray treatment time is preferably 1 second to 5 minutes, more preferably 2 seconds to 3 minutes, and particularly preferably 2 seconds to 2 minutes. If the spray treatment time is too short, the adhesion of the resulting polyimide film may not be improved, and if the spray treatment time is too long, the physical properties of the resulting polyimide film may deteriorate.

  For example, water can be sprayed or sprayed from a nozzle such as a spray nozzle and sprayed onto the polyimide film surface.

  As the spray nozzle, a flat type, a uniform flat type, a solid type, a full cone type, a hollow cone type, a fine spray type, and the like can be used.

  Although a spray pressure can be suitably selected according to the objective, Usually, 0.03-25 MPa is preferable, 0.05-10 MPa is more preferable, 0.1-1 MPa is especially preferable. If the spray pressure is too weak, the adhesion of the resulting polyimide film may not be improved, and if the spray pressure is too strong, the polyimide film may be torn.

  The distance between the spray nozzle and the film can be appropriately selected according to the purpose, and for example, it can be preferably processed in the range of 1 to 50 cm.

  One or a plurality of nozzles are arranged so that the entire film surface can be uniformly processed.

  If necessary, one side of the polyimide film may be sprayed with water, or both sides may be sprayed with water. When spraying both surfaces of the polyimide film, both surfaces can be processed simultaneously or one surface can be processed at a time.

  After the polyimide film surface is treated with water, the polyimide film can be dried as it is without post-treatment.

  For example, in a water treatment tank (spray tank) and a drying tank where individual polyimide films are fixed to a resin frame or the like, or long polyimide films are continuously arranged in a roll-to-roll manner By carrying it, continuous processing from spraying water to drying can be performed.

  The polyimide film can be dried using a hot air furnace or a heater.

  The polyimide film of the present invention thus obtained has good adhesiveness, particularly adhesion with an adhesive, without using a coupling agent in the production of the polyimide film. After heat treatment, for example, at 150 ° C. Even after the heat treatment for 24 hours, it has high adhesiveness. The polyimide film of the present invention has, for example, an initial 90 degree peel strength with a coverlay (before heat treatment) and after a heat test at 150 ° C. for 24 hours without using a coupling agent in the production of the polyimide film. Excellent adhesiveness of 3 N / mm or more, further 0.4 N / mm or more. As a coverlay, an epoxy adhesive or an acrylic adhesive is generally laminated in a semi-cured state on a polyimide film or a polyethylene terephthalate film. For example, “Coverlay (general type) manufactured by Arisawa Manufacturing Co., Ltd. ) (Product name) CV (product number) series ”, anti-migration coverlay (product name) CF, CT (product number) series”, “TFA560 series (product name), TFA577 series (product name)” manufactured by Kyocera Chemical Co., Ltd., DuPont Co., Ltd. “Piralux LF / FR series (product name)” manufactured by Nikkan Kogyo Co., Ltd. “Nikaflex CTSV series (product name), Nikaflex CISV series (product name), Nikaflex CISA series (product name), Nikaflex CKSE series (product name)” , Nikaflex CISG series Name), NIKAFLEX CKSG series (product name) ", Taiflex Scientific co. , Ltd., Ltd. “FHK series (product name), FD series (product name), FI series (product name)”, etc. can be mentioned.

  By using the polyimide film of the present invention, a polyimide film having (laminated) an adhesive, a photosensitive material, a thermocompression bonding material, or the like can be obtained.

  The polyimide film obtained by the present invention has good adhesion, sputtering and metal vapor deposition, and adheres metal foil such as copper foil using an adhesive, or copper by metalizing methods such as sputtering and metal vapor deposition. By providing a metal layer such as a layer, a metal laminated polyimide film such as a copper laminated polyimide film having excellent adhesion and sufficient peel strength can be obtained. Furthermore, a metal foil laminated polyimide film can be obtained by laminating a metal foil such as a copper foil on a polyimide film obtained according to the present invention using a thermocompression-bondable polymer such as a thermocompression bonding polyimide. The metal layer can be laminated according to a known method.

  The thickness of the copper layer of the copper laminated polyimide film can be appropriately selected depending on the purpose of use, but is preferably about 1 μm to 50 μm, and more preferably about 2 μm to 20 μm.

  As the metal foil to be bonded to the polyimide film via an adhesive, the type and thickness of the metal may be appropriately selected depending on the application to be used. For example, rolled copper foil, electrolytic copper foil, copper alloy foil, aluminum foil, stainless steel foil , Titanium foil, iron foil, nickel foil and the like, and the thickness is preferably about 1 μm to 50 μm, and more preferably about 2 μm to 20 μm.

  In addition, the polyimide film obtained by the present invention and another resin film, a metal such as copper, or a chip member such as an IC chip can be bonded using an adhesive.

  As the adhesive, known adhesives can be used depending on the application, such as those excellent in insulation and adhesion reliability, or those excellent in conductivity and adhesion reliability by pressure bonding such as ACF. Thermoplastic adhesives And thermosetting adhesives.

  Examples of the adhesive include polyimide-based, polyamide-based, polyimide-amide-based, acrylic-based, epoxy-based, urethane-based adhesives, and adhesives including two or more of these, particularly acrylic-based and epoxy-based adhesives. It is preferable to use a urethane-based or polyimide-based adhesive.

  The metallizing method is a method of providing a metal layer different from metal plating or metal foil lamination, and a known method such as vacuum deposition, sputtering, ion plating, or electron beam can be used.

  Metals used in the metalizing method include metals such as copper, nickel, chromium, manganese, aluminum, iron, molybdenum, cobalt, tungsten, vanadium, titanium, tantalum, or alloys thereof, or oxides or metals of these metals. Metal compounds such as carbides can be used, but are not particularly limited to these materials. The thickness of the metal layer formed by the metalizing method can be appropriately selected according to the purpose of use, and the range of preferably 1 nm to 500 nm, more preferably 5 nm to 200 nm is preferable for practical use. The number of metal layers formed by the metalizing method can be appropriately selected according to the purpose of use, and may be one layer, two layers, or three or more layers.

  In the metal laminated polyimide film obtained by the metalizing method, a metal plating layer of copper, tin or the like can be provided on the surface of the metal layer by a known wet plating method such as electrolytic plating or electroless plating. The thickness of the metal plating layer such as copper plating is preferably in the range of 1 μm to 40 μm because it is suitable for practical use.

  According to the present invention, for example, the 90 degree peel strength is 0.3 N / mm or more, even 0.4 N / mm or more, particularly 0.5 N / mm, even if no coupling agent is used in the production of the polyimide film. The copper laminated polyimide film as described above can be obtained.

  The polyimide film of the present invention is made of an insulating substrate material such as FPC, TAB, COF or a metal wiring base material, a cover base material such as a metal wiring or a chip member such as an IC chip, a liquid crystal display, an organic electroluminescence display, an electronic paper, a solar It can be suitably used as a base substrate for batteries and the like.

  The linear expansion coefficient of the polyimide film may be appropriately selected according to the purpose of use. For example, FPC, TAB, COF, insulating substrate materials such as metal wiring base materials, metal wiring, covers such as chip members such as IC chips, etc. When used for a substrate, etc., it is generally preferred that the linear expansion coefficient of the polyimide film is close to the linear expansion coefficient of a chip member such as a metal wiring or IC chip. Specifically, both MD and TD are 40 ppm. / ° C. or less, preferably 10 to 30 ppm / ° C., more preferably 11 to 25 ppm / ° C., and particularly preferably 12 to 20 ppm / ° C. According to this invention, while being excellent in adhesiveness, the polyimide film whose linear expansion coefficient is close to the linear expansion coefficient of copper is obtained.

  In some applications, such as COF and interposer, the linear expansion coefficient of the polyimide film is preferably close to that of glass or silicon. According to the present invention, a polyimide film having a linear expansion coefficient of 0 to 10 ppm / ° C. can also be obtained.

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

  The measurement of the coverlay adhesive strength of the polyimide film was performed according to the following method.

  Cover polyimide CVA0525KA manufactured by Arisawa Manufacturing Co., Ltd. was pressed and bonded to the obtained polyimide film at 180 ° C. and 3 MPa for 30 minutes. And 90 degree peel strength was measured with the peeling rate of 50 mm / min, and it was set as initial stage adhesive strength.

  Further, after the cover lay was bonded, it was treated in a hot air dryer at 150 ° C. for 24 hours, and the 90 ° peel strength was measured in the same manner as the post-heat-resistant adhesive strength.

  In addition, when the polyimide precursor solution was cast on the metal support during the production of the polyimide film, the surface on the air side was the A surface and the surface on the metal support side was the B surface.

(Production Example 1)
After adding a predetermined amount of N, N-dimethylacetamide, paraphenylenediamine (PPD) and 2,4-toluenediamine (TDA) to the polymerization tank, the mixture was stirred at 40 ° C. while 3,3 ′, 4,4 ′. -A polyamic acid solution (polyimide precursor solution) having a solid content concentration of 20% by mass by adding biphenyltetracarboxylic dianhydride (s-BPDA) to the diamine component (PPD + TDA) stepwise to approximately equimolar and reacting. ) The ratio of PPD and TDA was PPD: TDA = 8: 2 in molar ratio. Then, to this polyamic acid solution, add monostearyl phosphate triethanolamine salt at a ratio of 0.25 parts by mass and colloidal silica at a ratio of 0.3 parts by mass to 100 parts by mass of the polyamic acid, and uniformly Mixed. The rotational viscosity at 30 ° C. of the obtained polyamic acid solution composition was 260 Pa · s.

  Next, 0.05 equivalent of 1,2-dimethylimidazole was added to the polyamic acid solution composition with respect to the amic acid unit. The polyamic acid solution composition is continuously extruded from the slit of the T-die mold onto a smooth metal support in a casting / drying furnace to form a thin film, heated at 140 ° C. for a predetermined time, and then peeled off from the support. A self-supporting film was obtained. The heat loss (solvent content) of the obtained self-supporting film was 30.1% by mass, and the imidization ratio was 8.0% on the A side and 18.4% on the B side.

  Next, gripping both ends of the self-supporting film in the width direction and inserting it into a continuous heating furnace (curing furnace), heating the film under conditions where the maximum heating temperature is 450 ° C. from 100 ° C., imidizing, A long polyimide film (PI-1) having an average film thickness of about 13 μm was produced.

(Production Example 2)
TDA is not used as the diamine component, only PPD is used, the solid content concentration of the polyamic acid solution is 18% by mass, and the heating temperature at the time of preparing the self-supporting film is 150 ° C. A long polyimide film (PI-2) having an average film thickness of about 13 μm was produced. The rotational viscosity at 30 ° C. of the polyamic acid solution composition obtained here was 180 Pa · s. The heat loss of the self-supporting film was 27.7% by mass, and the imidization ratio was 17.9% on the A side and 29.3% on the B side.

(Comparative Example 1)
The coverlay adhesive strength of the polyimide film (PI-1) obtained in Production Example 1 was measured. The results are shown in Table 1.

Example 1
Four sides of the polyimide film (PI-1) obtained in Production Example 1 are fixed to a resin frame using an adhesive tape, and the A side and B side of the film are sprayed by a continuous device consisting of a pure water tank and a drying tank. -Dried. In the pure water tank, pure water was sprayed from the flat spray nozzle at room temperature and 0.1 MPa, and in the drying tank, the polyimide film was dried at 50 ° C. The residence time (spray treatment time) in the pure water tank was 3 seconds. And the coverlay adhesive strength of the obtained polyimide film was measured. The results are shown in Table 1.

(Example 2)
Spray treatment and drying were performed in the same manner as in Example 1 except that the residence time (spray treatment time) in the pure water tank was 6 seconds. And the coverlay adhesive strength of the obtained polyimide film was measured. The results are shown in Table 1.

(Reference Example 1)
The coverlay adhesive strength of the polyimide film (PI-2) obtained in Production Example 2 was measured. The results are shown in Table 1.

  From Comparative Example 1 and Reference Example 1, the polyimide film of s-BPDA / (PPD + TDA) has a particularly high initial adhesive strength as compared with the polyimide film of s-BPDA / PPD into which TDA is not introduced.

  From Comparative Example 1 and Examples 1-2, when the polyimide film of s-BPDA / (PPD + TDA) is sprayed with pure water, both the initial adhesive strength and the adhesive strength after the heat resistance test may be further increased. I understand.

  As described above, according to the present invention, a polyimide film obtained from a tetracarboxylic acid component and a diamine component containing the diamine represented by the general formula (1), preferably 3,3 ′, 4,4 ′. A tetracarboxylic acid component mainly composed of biphenyltetracarboxylic dianhydride and / or pyromellitic acid anhydride and paraphenylenediamine and / or diaminodiphenyl ether as a main component, and represented by the general formula (1) It is possible to further improve the adhesion of a polyimide film obtained from a diamine component, preferably 2,4-toluenediamine and a diamine component containing 3 mol% or more and less than 35 mol% in a simple method.

  The polyimide film of the present invention has excellent adhesion, insulating substrate materials such as FPC, TAB, COF or metal wiring substrate, cover substrates such as metal wiring and chip members such as IC chips, liquid crystal displays, organic electroluminescence It can be suitably used as a base material for displays, electronic paper, solar cells and the like.

Claims (4)

A tetracarboxylic acid component containing 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 2,4-toluenediamine and / or 2,6-toluenediamine in an amount of 3 mol% or more and less than 35 mol% It is a polyimide film obtained by reacting with a diamine component further containing paraphenylenediamine ,
A polyimide film characterized by being surface-treated by spraying water on the surface. The tetracarboxylic acid component contains 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride in an amount of 50 mol% or more ,
The diamine component, and characterized in that comprises a paraphenylene Amin least 50 mol%, further comprising a 2,4-toluenediamine and / or 2,6-toluenediamine in the range of less than 3 mol% to 35 mol% The polyimide film according to claim 1 . The adhesive lamination polyimide film formed by laminating | stacking an adhesive bond layer on the surface which sprayed the water of the polyimide film of Claim 1 or 2, and surface-treated. A tetracarboxylic acid component containing 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 2,4-toluenediamine and / or 2,6-toluenediamine in an amount of 3 mol% or more and less than 35 mol% A step of casting a polyamic acid or polyimide solution obtained by reacting with a diamine component further containing paraphenylenediamine on a support and drying it to obtain a self-supporting film;
Heating the self-supporting film to obtain a polyimide film;
The manufacturing method of the polyimide film which has the process of spraying water on the surface of the obtained polyimide film.