JP2005001384A - Laminate and manufacturing method for printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed wiring board on which a high-density circuit can be formed and which shows excellent adhesion and good adhesion reliability under high-temperature and high-humidity environment. <P>SOLUTION: A plating film showing excellent adhesion force is formed on a smooth surface by using a layered product comprising a thermoplastic polyimide resin containing an organic thiol-derivative compound and a metal thin film formed by a physical method. The high-density circuit is formed by using it. The manufacture of the printed wiring board by using the layered product enables formation of the high-density printed wiring board and achieves good adhesion and excellent adhesion reliability under high-temperature and high-humidity environment. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a laminate composed of a polymer film containing a polyimide resin and metal suitable for the production of a printed wiring board, and a method for producing a printed wiring board using the laminate.

  By manufacturing printed wiring boards using these laminates, high-density flexible printed wiring boards excellent in adhesiveness, multilayer flexible printed wiring boards laminated with flexible printed wiring boards, flexible printed wiring boards and rigid printed wiring boards Rigid-flex wiring boards, build-up wiring boards, TAB (Tape Automated Bonding) tapes, COF (Chip On Film) boards in which semiconductor elements are directly mounted on printed wiring boards, MCM (Multi Chip Module) boards, Etc. can be obtained.

Printed wiring boards are widely used for mounting electronic components and semiconductor elements. With recent demands for downsizing and higher functionality of electronic devices, such printed wiring boards have higher circuit density and Thinning is strongly desired. In particular, establishment of a fine circuit forming method in which the line / space spacing is 20 μm / 20 μm or less is an important issue in the field of printed wiring boards.
Usually, in a printed wiring board, adhesion between a polymer film serving as a substrate and a circuit is achieved by surface irregularities called an anchor effect. Therefore, generally, a step of roughening the film surface is provided, and the surface is usually provided with unevenness of about 3 to 5 μm in terms of Rz value. Such unevenness on the surface of the substrate is not a problem when the line / space value of the circuit to be formed is 30/30 μm or more, but it is a serious problem especially for forming a circuit with a line width of 20/20 μm or less. Become. The reason is that the circuit lines, which are such high-density thin lines, are affected by the unevenness of the substrate surface. Therefore, in order to form a circuit having a line / space value of 20/20 μm or less, a technology for forming a circuit on a polymer substrate having high surface smoothness is required, and its flatness is 2 μm or less, preferably 1 μm in terms of Rz value. Must be: Of course, in this case, the anchor effect cannot be expected as an adhesive force, so that it is necessary to develop another bonding method.

  Further, in the case of a printed wiring board that forms a circuit, it is indispensable to form a via hole that conducts both sides of the wiring board. Therefore, such a printed wiring board is usually subjected to circuit formation through a laser via hole forming process, a desmear process, a catalyst application process, an electroless plating copper process, and the like. Furthermore, circuit formation may be performed by a subtractive method using etching, or may be manufactured by a semi-additive method or an additive method. Therefore, in the printed wiring board on which the fine wiring as described above is formed, the adhesion between the wiring circuit and the polymer film needs to withstand these processes.

  Several attempts have been made to improve the adhesion between a metal thin film formed on a resin surface having a small surface roughness and the resin by a physical method such as sputtering or vapor deposition. For example, a method of adding a titanium-based organic compound to a polyimide film (Patent Document 1), or a method of improving adhesive force by coating a metal salt made of Sn, Cu, Zn, Fe, Co, Mn, or Pd ( Patent Document 2), a method of metalizing an imidized polyimide film after applying a heat-resistant surface treatment agent to a polyamic acid solidified film, (Patent Document 3), a method of allowing titanium element to exist on the surface of the polyimide film (Patent Document 4) ), Is disclosed. Further, there is a method (Patent Document 5) in which the present inventors form a conductor layer on the surface of a thermoplastic polyimide by a dry plating method, and press and heat bond the conductor layer to enhance the adhesion strength between the polyimide and the adhesive layer. It is disclosed.

  The copper metal layer formed by physical methods, such as vapor deposition and sputtering, on these polyimide film surfaces has the adhesive strength outstanding compared with the copper metal layer formed in the normal polyimide film surface. However, the metal layer is weak in desmearing and electroless plating processes, often resulting in a decrease in adhesive strength, and the process window may become extremely narrow in an actual process.

  On the other hand, as a method for realizing strong adhesion between the metal foil and the polyimide resin, there is a method in which the surface of the copper metal foil is surface-treated in advance. For example, after treating the copper foil surface with a solution of polybenzimidazole and a solution of 4-aminophenyl disulfide, a film of polyamic acid which is a precursor of polyimide resin is formed, and this is overheated to form polyimide. It has been reported. However, although this method uses a surface-treated metal foil, it is suitable only for circuit formation by the subtra method, but a high-density circuit of 20/20 μm or less is effective as a forming means. It has the disadvantage that it cannot be applied to additive and additive methods.

  On the other hand, as a wet process used for printed wiring boards, that is, as a method of directly forming an electroless plating film on a resin material, a method of forming electroless plating on the roughened surface of the epoxy resin surface is disclosed. . However, it adheres well if the surface roughness Rz is 3 μm or more, but it is known that it only shows adhesiveness of about 3 N / cm when it is 3 μm or less, especially about 1 μm, and its improvement is necessary. . (Patent Document 6) On the other hand, as a method for directly generating an electroless plating film on a polyimide resin without surface roughening, an organic disulfide compound having a primary amino group and / or primary amino in a solution containing caustic alkali A method of treating with a solution containing an organic thiol compound having a group is disclosed. (Patent Document 7) However, the adhesive strength between the electroless plating film obtained by this method and the polyimide resin is still insufficient.

  On the other hand, hydrogen sulfide and thiol compounds are known to react with metals and metal compounds to form stable salts. (Non-Patent Document 2) A method of using this phenomenon to treat a metal surface with a thiol derivative, particularly a triazine thiol derivative, to improve adhesion is disclosed. (Patent Documents 9 and 10) For example, methods such as treatment to a magnesium alloy and adhesion between rubber and a metal plating layer are disclosed. (Patent Documents 11 and 12) However, no attempt has been made to apply these adhesion techniques using a triazine thiol derivative to a manufacturing process of a printed wiring board, and polyimide which is an important base material for a printed wiring board in particular. No attempt has been made to apply this method to a manufacturing process using the above.

As described above, the conventional technology has been described. However, a strong adhesion is realized by using a thin film physically formed on a very smooth polyimide resin surface so that the surface roughness Rz is 1 μm or less, and a normal printed wiring is used. No manufacturing method has been developed that has sufficient resistance to the wet process, which is a plate manufacturing process.
Patent No. 1,948,445 (US Pat. No. 4,742,099) JP-A-6-73209 (US Pat. No. 5,227,224) US Pat. No. 5,130,192 JP 11-71474 A (published March 16, 1999) JP 2002-113812 A (released on April 16, 2002) Japanese Unexamined Patent Publication No. 2000-198907 (released July 18, 2000) JP 2002-208768 A (published July 26, 2002) Japanese Patent Laid-Open No. 2001-1445 (released on January 9, 2001) Japanese Patent Laid-Open No. 10-237047 (published on September 8, 1998) JP 2000-160392 A (released on June 13, 2000) JP 2000-159933 A (released on June 13, 2000) JP 09-71664 A (published March 18, 1997) Gi Xue, et.al., `` Adhesion Promotion at High Temperature for Epoxy Resinor polyimide onto Metal by a Two-Component Coupling System of Polybenzimidazole and 4-Aminophenyl Disulfide '', Journal of Applied Polymer Science 1995, 58, 2221 The Chemical Society of Japan, “Experimental Chemistry Course 24”, Maruzen Shoten, September 25, 1992, P320

  The present invention has been made to remedy the above-mentioned problems. The object of the present invention is a polyimide surface having a small ten-point average surface roughness Rz, for example, 1 μm or less and having a very high flatness. A fine circuit having a line width of 20/20 μm or less can be formed, and the adhesive force between the circuit and the polyimide surface can be improved. It is to provide a bonding method that has resistance to the manufacturing process.

The present invention provides the following novel laminate, which can solve the above problems.
1) A laminate having a polymer film containing at least an organic thiol compound and a polyimide resin, and a metal thin film formed on at least one surface thereof by a physical method.
2) The laminate according to 1), wherein the physical method is at least one method selected from a vapor deposition method, a sputtering method, and an ion plating method.
3) The laminate according to 1) or 2), wherein the organic thiol compound is an organic dithiol compound and / or an organic trithiol compound.
4) The laminate according to 3), wherein the organic dithiol compound and / or the organic trithiol compound is a triazine thiol derivative.
5) The laminate according to any one of 1) to 4), wherein the polyimide resin is a thermoplastic resin.
6) The polymer film containing the polyimide resin is a non-thermoplastic polyimide resin, polyamideimide resin, polyetherimide resin, polyamide resin, aromatic polyester resin, polycarbonate resin, polyacetal resin, polysulfone resin, polyethersulfone resin, polyethylene A film in which a layer having a thermoplastic polyimide resin layer is provided on one or both sides of a film made of a resin selected from terephthalate resin, phenylene ether resin, polyolefin resin, polyarylate resin, liquid crystal polymer, and epoxy resin 1) to The laminate according to any one of 5).
7) The thermoplastic polyimide resin is represented by the following general formula (1)

（式中、ＡおよびＢは４価の有機基、ＸおよびＹは２価の有機基であり、ｍは０≦ｍ≦１、ｎは０≦ｎ≦１の範囲の値でｍ＋ｎ＝１であり、ｋは任意の整数である）。で表されるポリアミド酸を脱水閉環して得られる熱可塑性ポリイミドである）１）〜６）のいずれか一項に記載の熱可塑性ポリイミド樹脂材料を用いた事を特徴とする積層体。
８）前記一般式（１）中のＡおよびＢは、群（１）

(In the formula, A and B are tetravalent organic groups, X and Y are divalent organic groups, m is 0 ≦ m ≦ 1, n is a value in the range of 0 ≦ n ≦ 1, and m + n = 1. And k is an arbitrary integer). A laminate obtained by using the thermoplastic polyimide resin material according to any one of 1) to 6), which is a thermoplastic polyimide obtained by dehydrating and ring-closing the polyamic acid represented by formula (1).
8) A and B in the general formula (1) are a group (1)

（式中のＡは同一であっても異なっていても良く、Ｂは同一であっても異なっていても良い）。
から選択される少なくとも１種以上である７）記載の積層体。
９）前記一般式（１）中のＸおよびＹは下記一般式（３）

(A in the formula may be the same or different, and B may be the same or different).
7. The laminate according to 7), which is at least one selected from the group consisting of:
9) X and Y in the general formula (1) are the following general formula (3)

（式中のＸは同一であっても異なっていても良く、Ｙは同一であっても異なっていても良い）。から選択される少なくとも１種以上である７）または８）記載の積層体。
１０）１）〜９）記載の積層体を用いてなるプリント配線板の製造方法。

(X in the formula may be the same or different, and Y may be the same or different). The laminate according to 7) or 8), which is at least one selected from the group consisting of:
10) A method for producing a printed wiring board using the laminate according to 1) to 9).

  By using a laminate composed of a thermoplastic polyimide resin containing an organic thiol of the present invention and a metal thin film formed by a physical method, it is possible to form a high-density circuit having excellent adhesion strength on a smooth surface. is there.

  The main point of the present invention to achieve the object of the present invention is to use a polyimide resin containing at least an organic thiol compound in order to realize strong adhesion between a metal film formed by a physical method and a resin substrate. is there. Usually, metal thin films formed by physical methods such as vapor deposition, sputtering, and ion plating are either physically bonded by metal fine particles physically biting into the resin, or simply chemically adsorbed on the surface. It is in the state of. However, by using the method of the present invention, adhesion with a strong chemical bonding force is performed. That is, it is considered that a chemical bond between the polyimide and the metal was formed through the organic thiol compound. It has been known that organic thiol compounds show strong adhesion to metals, but when added to polyimide resin, strong adhesion can be realized with metal films formed by physical methods. However, as will be described later, it has been found for the first time that it has a sufficient resistance to a normal printed circuit board manufacturing process. Hereinafter, embodiments of the present invention will be specifically described.

(Polyimide resin)
First, the film which has a polyimide resin based on this invention is demonstrated. Polyimide resins include thermoplastic polyimide resins and non-thermoplastic polyimide resins. First, the non-thermoplastic polyimide resin film will be described. The polyimide film used in the present invention can be produced by a known method disclosed in “Journal of Polymer Science: part A vol. 3 PP. 1373-1390 (1965)”. That is, it can be obtained by casting and coating polyamic acid on a support and imidizing chemically or thermally.
Basically, any known polyamic acid can be applied to the polyamic acid, which is a polyimide precursor used in the present invention. The polyamic acid used in the present invention is usually a polyamic acid organic solvent obtained by dissolving a substantially equimolar amount of at least one aromatic dianhydride and at least one diamine in an organic solvent. The solution is prepared by stirring under controlled temperature conditions until polymerization of the acid dianhydride and diamine is complete. In addition, polyimide is obtained by imidizing polyamic acid. For imidation, either a thermal cure method or a chemical cure method is used. The thermal cure method is a method in which an imidization reaction proceeds by heating alone without the action of a dehydrating ring-closing agent or the like. In addition, the chemical cure method includes a polyamic acid organic solvent solution, a chemical conversion agent (dehydrating agent) represented by acid anhydrides such as acetic anhydride, and tertiary amines such as isoquinoline, β-picoline, and pyridine. This is a method in which a catalyst represented by A thermal curing method may be used in combination with the chemical curing method. The reaction conditions for imidization may vary depending on the type of polyamic acid, film thickness, thermal curing method and / or chemical curing method.

  Here, the material used for the polyimide precursor polyamic acid which concerns on this invention is demonstrated. Suitable acid anhydrides for use in this polyimide are pyromellitic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic. Acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone Tetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis (3,4-dicarboxy) Phenyl) propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3 -Dicarboxyl Nyl) methane dianhydride, bis (3,4-dicarboxyphenyl) ethane dianhydride, oxydiphthalic dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, p-phenylenebis (trimerit Acid monoester acid anhydride), ethylene bis (trimellitic acid monoester acid anhydride), bisphenol A bis (trimellitic acid monoester acid anhydride), and the like.

  Of these, the most suitable acid dianhydride for the laminate according to the present invention is pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′. , 4,4′-biphenyltetracarboxylic dianhydride, p-phenylenebis (trimellitic acid monoester acid anhydride), and these are preferably used alone or in a mixture in any proportion. Suitable diamines that can be used in the polyimide composition according to the present invention are 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenylmethane, benzidine, 3,3′-dichlorobenzidine, 4,4′-diaminodiphenyl. Sulfide, 3,3′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1,5-diaminonaphthalene 4,4′-diaminodiphenyldiethylsilane, 4,4′-diaminodiphenylsilane, 4,4′-diaminodiphenylethylphosphine oxide, 4,4′-diaminodiphenyl N-methylamine, 4,4′-diaminodiphenyl N-phenylamine, , 4-diaminobenzene (p- phenylene diamine), including 1,3-diaminobenzene, 1,2-diaminobenzene, and their analogs. Among the diamines used for these polyimide films, 4,4′-diaminodiphenyl ether and p-phenylenediamine are particularly preferred, and these are in a molar ratio of 100: 0 to 0: 100, preferably 100: 0 to 10:90. Mixtures mixed in proportions can be preferably used.

  Preferred combinations of acid dianhydrides and diamines for the present invention are pyromellitic dianhydride and 4,4′-diaminodiphenyl ether, pyromellitic dianhydride, 4,4′-diaminodiphenyl ether and p-phenylenediamine. A combination, or a combination of pyromellitic dianhydride, p-phenylenebis (trimellitic acid monoester anhydride), 4,4′-diaminodiphenyl ether and p-phenylenediamine. Polyimides synthesized by combining these monomers exhibit excellent properties such as moderate elastic modulus, dimensional stability, and low water absorption, and are suitable for use in the laminate of the present invention. Preferred solvents for synthesizing the polyamic acid are amide solvents, ie N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and the like, and N, N-dimethylformamide is particularly preferred. Preferably used.

  Further, when the imidization is performed by a chemical cure method, the chemical conversion agent added to the polyamic acid composition according to the present invention is, for example, an aliphatic acid anhydride, an aromatic acid anhydride, N, N′-dialkylcarbodiimide, Examples thereof include lower aliphatic halides, halogenated lower aliphatic halides, halogenated lower fatty acid anhydrides, arylphosphonic acid dihalides, thionyl halides, and mixtures of two or more thereof. Of these, aliphatic anhydrides such as acetic anhydride, propionic anhydride, and lactic acid anhydride, or a mixture of two or more thereof can be preferably used. These chemical conversion agents are preferably added in an amount of 1 to 10 times, preferably 1 to 7 times, more preferably 2 to 5 times the number of moles of the polyamic acid moiety in the polyamic acid solution. Moreover, in order to perform imidation effectively, it is preferable to use a catalyst simultaneously with a chemical conversion agent. As the catalyst, aliphatic tertiary amine, aromatic tertiary amine, heterocyclic tertiary amine and the like are used. Among them, those selected from heterocyclic tertiary amines can be particularly preferably used. Specifically, quinoline, isoquinoline, β-picoline, pyridine and the like are preferably used. These catalysts are added in an amount of 1/20 to 10 times, preferably 1/15 to 5 times, more preferably 1/10 to 2 times the number of moles of the chemical conversion agent.

Moreover, it is preferable to use a thermoplastic polyimide resin as a film having a polyimide resin in the present invention. The thermoplastic polyimide film will be described.
As thermoplastic polyimide, the following general formula (1)

（式中、ＡおよびＢは４価の有機基、ＸおよびＹは２価の有機基である。で表されるポリアミド酸を脱水閉環して得られる熱可塑性ポリイミドであり、ｍは０≦ｍ≦１、ｎは０≦ｎ≦１の範囲の値でｍ＋ｎ＝１であり、ｋは任意の整数である）であることが好ましく、さらに。前記一般式（１）中のＡおよびＢは、群（１）

(In the formula, A and B are tetravalent organic groups, and X and Y are divalent organic groups. Thermoplastic polyimide obtained by dehydrating and ring-closing the polyamic acid represented by: m is 0 ≦ m. Preferably, ≦ 1, n is a value in the range of 0 ≦ n ≦ 1, m + n = 1, and k is an arbitrary integer. A and B in the general formula (1) are groups (1)

（式中のＡは同一であっても異なっていても良く、Ｂは同一であっても異なっていても良い）。
から選択される少なくとも１種以上であることが好ましい。また、前記一般式（１）中のＸおよびＹは群（２）

(A in the formula may be the same or different, and B may be the same or different).
It is preferable that it is at least 1 or more types selected from. X and Y in the general formula (1) are groups (2).

（式中のＸは同一であっても異なっていても良く、Ｙは同一であっても異なっていても良い）。であることが好ましい。

(X in the formula may be the same or different, and Y may be the same or different). It is preferable that

  Among these combinations of acid dianhydrides and diamines for obtaining the thermoplastic polyimide resin of the present invention, at least one selected from acid dianhydrides giving acid dianhydride residues listed in group (1) A combination of an acid dianhydride and at least one diamine selected from the diamines that give the diamine residues listed in the group (2) is preferred, and among them, 2,3,3 ', 4'- Biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, oxydiphthalic anhydride, ethylene bis (trimellitic acid monoester acid anhydride), bisphenol A bis (trimellitic) Acid monoester anhydride), 4,4 ′-(4,4′-isopropylidenediphenoxy) bis (phthalic anhydride), and 1,3-diammine as diamine Benzene, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis ( 4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) Phenyl] sulfone is industrially available, and the thermoplastic polyimide obtained has excellent characteristics such as low water absorption, low dielectric constant, low dielectric loss tangent, etc., and is an effect of the present invention. It can be used particularly preferably because it exhibits the effect of increasing the adhesive strength with the electrolytic plating film.

  The polyamic acid which is a precursor of the thermoplastic polyimide used in the present invention is obtained by dissolving and reacting at least one of the above acid dianhydrides and at least one of diamines in an organic solvent in a substantially equimolar amount. Thus, a polyamic acid organic solvent solution as a precursor is obtained.

  A thermoplastic polyimide resin is obtained by imidizing a precursor polyamic acid, and either immobilization or thermal curing is used for imidization. The thermal cure method is a method in which an imidization reaction proceeds by heating alone without the action of a dehydrating ring-closing agent or the like. The chemical cure method is represented by a polyhydric acid organic solvent solution, a chemical dehydrating agent typified by acid anhydrides such as acetic anhydride, and tertiary amines such as isoquinoline, β-picoline, and pyridine. This is a method of working with a catalyst. It is also possible to use a carbodiimide compound such as dicyclohexylcarbodiimide as a dehydrating agent. Of course, the thermal curing method may be used in combination with the chemical curing method, and the imidation reaction conditions may vary depending on the type of polyamic acid, the form of the resin obtained, the selection of the thermal curing method and / or the chemical curing method, and the like. . Preferred solvents for synthesizing the polyamic acid are amide solvents, ie N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone and the like, and N, N-dimethylformamide is particularly preferred. Preferably used.

  The thermoplastic polyimide resin material of the present invention can take various forms, such as a molded body, a single layer film, or a laminate in which a layer made of a thermoplastic polyimide resin is formed on a support.

  Several methods are conceivable for producing the film-like thermoplastic polyimide resin. When the thermoplastic polyimide is insoluble in the solvent, the solution of the precursor polyamic acid is cast-coated on the support in the form of a film and imidized by the above-described imidization method, that is, the thermal cure method or the chemical cure method. It is preferable to dry the solvent to form a film-like material. When the thermoplastic polyimide exhibits solvent solubility, once the thermoplastic polyimide resin is obtained in the form of powder, fiber, or film, the thermoplastic polyimide solution dissolved in the solvent is flowed on the support in the form of a film. It is also possible to apply it by spread. It is also possible to form a film by the same method as when it is insoluble.

  As a film having a polyimide resin, in addition to the non-thermoplastic polyimide resin film single layer and the thermoplastic polyimide resin single layer obtained as described above, a thermoplastic polyimide resin layer is provided on one or both sides of the non-thermoplastic polyimide film. It can be a film. These films may contain various additives.

(Organic thiol compound)
Next, the organic thiol compound of the present invention will be described. The organic thiol derivative used in the present invention refers to a compound having one or more SM groups (wherein M is any element selected from H, Li, Na, K) in one molecule, and two or more More preferred are dithiol compounds and / or trithiol compounds which are compounds having the following SM groups. The reason why a compound having two or more SM groups is more preferable is that at least one of the SM groups forms a chemical bond with the thermoplastic polyimide, and the mechanism in which the other SM group binds to the metal is due to a strong adhesive expression. Because it is important.

  The specific compound is not particularly limited as long as it achieves the object of the present invention. For example, monothiols include 2-markaptopyridine, 2-markertopyrimidine, 2-markertobenzimidazole. , 2-markertobenzothiazole, 2-markertobenzoxazole, 2-markertoethanol, 4-markerbutanol, 5-methyl-1,3,4-thiazole-2-thiol, and the like. .

  Examples of the dithiols include 2,5-dimarkapt-1,3,4-thiadiazole, 2,3-dimarkap-1-propanol, 2,6-dimarkaptopurine, 2,5-dimarkapto-1,3,4. -Thiadiazole, dipotassium salt, 2-markertoethyl ether, 2-markertoethyl sulfide, etc. can be illustrated.

  Of these, triazine dithiol derivatives or triazine trithiol derivatives are preferably used. Here, the triazine thiol derivative is a compound represented by the following general formula (2) or general formula (3).

ただし、Ｍ１、Ｍ２はそれぞれ、Ｈ、Ｌｉ，Ｎａ，Ｋから選ばれる任意の元素であり、一般式（２）におけるＲは、Ｈ、または炭素数が１〜１８の任意の飽和アルキル基、炭素数が１〜１８のアルキン、アルケン等の不飽和アルキル置換基、フェニル基、アミノ基またはＳＨ基である。また一般式（３）におけるＲ１、Ｒ２はそれぞれ、Ｈ、炭素数が１〜１８の任意の飽和アルキル基、もしくは炭素数が１〜１８のアルキン、アルケンの様な不飽和アルキル置換基、フェニル基、アミノ基である。

However, M1 and M2 are each an arbitrary element selected from H, Li, Na and K, and R in the general formula (2) is H, an arbitrary saturated alkyl group having 1 to 18 carbon atoms, carbon It is an unsaturated alkyl substituent such as alkyne and alkene having 1 to 18 numbers, phenyl group, amino group or SH group. In the general formula (3), R1 and R2 are each H, an arbitrary saturated alkyl group having 1 to 18 carbon atoms, an alkyne having 1 to 18 carbon atoms, an unsaturated alkyl substituent such as an alkene, or a phenyl group. , An amino group.

Specifically, H as M1, H as M2, or Na, R as H, C ₂ H ₅ , C ₄ H ₉ , SH, N (CH ₃ ) ₂ , NH (C ₆ H ₅ ), N (C _{4 H 9) 2, N (} C 8 H 17) 2, N (C 12 H 25) 2, N (CH 2 CH = CH 2) 2, NHC 8 H 16 CH = CHC 8 H 17, NCH 2 C 6 _{H 4 CH = CH 2 (C} 8 H 17), NHC 6 H 4 N (CH 3) 2, and the like can be exemplified.

(Addition method)
The organic dithiol derivative and triazine thiol derivative as described above may be added to the polyimide resin in the present invention, and surface treatment such as solution immersion is performed in the production process of the printed wiring board, and the surface of the polyimide resin is triazine thiol derivative. A derivative may be supported.

  As a method of adding the organic thiol derivative of the present invention to the resin, it may be added in the state of polyamic acid which is a precursor of the polyimide resin, or may be added using a solvent that dissolves the polyimide resin and the organic thiol derivative. Good. Solvents used for such purposes include amide solvents, ie, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and N, N-dimethylformamide is particularly preferred. Used. Further, in the triazine thiol derivative, when at least one of M1 and M2 is an alkali metal such as Na, it is often soluble in an alkaline aqueous solution or alkaline methanol. It is preferably used for addition of a triazine thiol derivative. The addition amount of the organic dithiol derivative to the polyimide resin is 10% or less by weight, and the addition amount of 10% or more is not only unnecessary, but often has an adverse effect on physical properties such as the thermal expansion coefficient and elastic modulus of the polyimide resin. This is not preferable. More preferable addition amount of the organic dithiol derivative is 2% or less. Even if the addition amount is 1% or less, the effect is sufficiently exhibited, the effect is recognized even at 0.01%, and the effect can be confirmed even at 0.001%. There is a thing. The polyimide resin to which the organic thiol derivative thus prepared is added can be molded, monolayer film, laminated body in which a layer made of polyimide resin is formed on a support, etc. by the method described above. Can do.

  Next, a method for carrying out surface treatment and supporting a thiol derivative on the polyimide resin surface will be described. This method includes immersing the polyimide resin in a solvent in which the organic thiol derivative is dissolved, or using a solvent to swell and dissolve an appropriate thickness of the surface of the polyimide resin to carry the organic thiol compound on the surface. Preferably used. The organic thiazole compound firmly supported on the polyimide surface is firmly bonded to the metal thin film formed by a physical method, and as a result, it is possible to improve the adhesion to the electroless plating film.

  For example, as a solvent used for carrying out the method of the present invention, methanol, glycols, tetrahydrofuran, alkaline aqueous solution, alkaline methanol solution, amide solvent, that is, N, N-dimethylformamide, N, N-dimethylacetamide, N- Methyl-2-pyrrolidone and the like, and N, N-dimethylformamide is particularly preferably used. A combination of an aqueous alkali solution and an organic solvent is preferably used, and a combination of an aqueous sodium hydroxide solution and an ethylene glycol organic solvent is particularly preferably used. When treated with such a combination of solvents, the polyimide resin becomes swollen and is particularly effective for the purposes of the present invention. A mixed solution of potassium hydroxide / ethanolamine / water is also preferably used. In general, the organic thiol dissolved in such a solvent is preferably a 0.01 to 5% solution, particularly preferably a 0.1 to 1% solution. Processing conditions such as the concentration of organic thiol, processing time, and processing temperature are selected from conditions optimal for the purpose, and are not limited to the above ranges. The polyimide surface-treated with such a solvent is washed with water or methanol as necessary, and is sent to the next step, that is, a physical metal thin film forming step.

  The surface roughness Rz of the polyimide resin obtained by these treatments is 1 μm or less and extremely flat, but the adhesive strength with the metal thin film can be 6 N / cm or more. The smoothness of the surface treated by the method of the present invention is suitable for forming a high-density circuit having a line / space of 20/20 μm or less. Rz is stipulated in standards relating to the surface shape such as JIS B0601.

(Other ingredients)
In addition to the above-mentioned thermoplastic resins, epoxy resins, cyanate ester resins, and screws are used to improve various properties such as adhesion, heat resistance, and workability, as long as the properties such as heat resistance and low moisture absorption are not impaired. Thermosetting resins such as maleimide resin, bisallyl nadiimide resin, phenolic resin, acrylic resin, methacrylic resin, hydrosilyl cured resin, allyl cured resin, unsaturated polyester resin, and allyl group, vinyl at the side chain or terminal of polymer chain A side chain reactive group type thermosetting polymer having a reactive group such as a group, an alkoxysilyl group, and a hydrosilyl group can be contained alone or in appropriate combination.

(Metal layer)
Next, the metal layer according to the present invention will be described. First, physical methods such as vacuum deposition, ion plating, and sputtering can be applied as a method for forming the metal layer. In the present invention, the thickness of the metal layer formed by these methods is preferably 20 nm or more and 500 nm or less from the viewpoint of ease of carrying out the semi-additive method and economical efficiency. In particular, sputtering is preferable in view of the simplicity of equipment, productivity, and adhesion between the obtained conductor layer and the polymer film.

  When sputtering is used, a known method can be applied. That is, DC magnetron sputtering, RF sputtering, or a method obtained by variously improving these methods can be appropriately applied according to each requirement. For example, DC magnetron sputtering is preferable for efficiently sputtering a conductor such as nickel or copper. On the other hand, RF sputtering is suitable for sputtering in a high vacuum for the purpose of preventing mixing of sputtering gas in the thin film. The DC magnetron sputtering will be described in detail. First, a polymer film is set as a substrate in a vacuum chamber and evacuated. A combination of roughing with a normal rotary pump and a diffusion pump or cryopump is usually used to evacuate to 6 × 10 −4 Pa or less. Next, sputtering gas is introduced, the inside of the chamber is brought to a pressure of 0.1 Pa to 10 Pa, preferably 0.1 Pa to 1 Pa, and a DC voltage is applied to the metal target to cause plasma discharge. At this time, a magnetic field is formed on the target, and the generated plasma is confined in the magnetic field, thereby increasing the sputtering efficiency of the plasma particles on the target. While keeping the polymer film unaffected by plasma or sputtering, the surface of the metal target is removed (pre-sputtering) while maintaining the plasma for several minutes to several hours. After pre-sputtering is completed, the polymer film is sputtered by opening a shutter or the like. The discharge power during sputtering is preferably in the range of 100W to 1000W. Further, batch-type sputtering or roll sputtering is applied according to the shape of the sample to be sputtered. As the introduction sputtering gas, an inert gas such as argon is usually used, but a mixed gas containing a small amount of oxygen and other gases can also be used.

  In order to improve the adhesion between the polyimide film and the sputtered film, plasma discharge treatment, corona discharge treatment, heat treatment, ion bombardment treatment, or the like can be applied as pretreatment. Usually, if the polyimide film is exposed to the atmosphere after these treatments, the modified surface may be deactivated and the treatment effect may be greatly reduced. It is preferable to continuously sputter.

  Although the sputtering method described above can produce a uniform thin film with high accuracy, the copper or copper alloy thin film generally formed by the sputtering method achieves strong adhesion on a polymer film with excellent surface flatness. I can't do it. However, in the organic thiol compound-containing polyimide film according to the present invention, an adhesive strength of 5 N / cm or more can be realized, and when the polyimide film is a thermoplastic polyimide, an excellent adhesive strength of 7 N / cm or more is achieved. Was realized.

  The inventors of the present invention have further studied the efforts to improve the adhesive force and found that it is preferable to form a base metal between the resin substrate and the sputtering metal film for the purpose of realizing further excellent adhesion. As the base metal, nickel, chromium, titanium, molybdenum, tungsten, zinc, tin, indium, or an alloy thereof is used. In particular, it is effective to use nickel, chromium, titanium, and nickel or an alloy of nickel and chromium is used. It is particularly preferable to use it. The main purpose of using chromium and nickel alloys is to increase the sputtering rate. Although it is difficult to increase the sputtering rate with pure nickel metal as a magnetic material, the sputtering rate can be increased by using an alloy of nickel and chromium. In order to achieve this purpose, the ratio of chromium and nickel is not particularly limited, but generally it is preferably 2% or more. In addition, it is preferable that the thickness of such an undercoat layer is 1 nm or more and 10 nm. By providing such an undercoat layer, an adhesive having an intensity of 6 N / cm or more can be realized in an organic thiol compound-containing polyimide film. Furthermore, when the polyimide film is a thermoplastic polyimide, an excellent adhesive strength of 8 N / cm or more can be realized.

(Structure of laminate)
Next, the laminated body of this invention and the structure for implement | achieving a printed wiring board using this laminated body are described.

  The laminate in the present invention includes “metal layer / polymer film including polyimide resin”, “metal layer / polymer film including polyimide resin / metal layer”, “metal layer / polymer film including polyimide resin / metal copper”. “Foil layer”, “metal layer / polymer film containing polyimide resin / adhesive layer”, and the like can be employed. Here, the polymer film containing polyimide resin refers to a single film of polyimide resin or a laminated film of polyimide resin and another resin film. Examples of the single layer film of the polyimide resin include a single film made of a non-thermoplastic polyimide resin and a single film made of a thermoplastic polyimide resin. Naturally, the polyimide resin is characterized by containing an organic thiol derivative, but as described above, such an organic thiol derivative may be internally added to the polyimide resin in the form of various laminates. It may be added in the form of carrying out the treatment.

  The above "polymer film containing polyimide resin" is polyamideimide resin, polyetherimide resin, polyamide resin, aromatic polyester resin, polycarbonate resin, polyacetal resin, polysulfone resin, polyethersulfone resin, polyethylene terephthalate resin, phenylene ether resin, The printed wiring board has a laminate in which a thermoplastic polyimide resin layer is provided on one or both sides of a film made of at least one resin selected from polyolefin resin, polyarylate resin, liquid crystal polymer, and epoxy resin. It is preferable from the viewpoint that properties such as low thermal expansion, high elastic modulus, heat resistance and the like can be realized.

  In particular, the provision of a thermoplastic polyimide resin layer on one or both surfaces of a non-thermoplastic polyimide film can reduce the average thermal expansion coefficient, which is an important characteristic for printed wiring boards, and can also improve heat resistance and interface adhesion. From this point, it is more preferable. The “non-thermoplastic polyimide used in the laminate” according to the present invention is not particularly limited, and a known polyimide can be used as long as it satisfies heat resistance, dimensional stability, and interface adhesion. .

(Printed wiring board manufacturing method)
Next, the manufacturing method of the wiring board using the said laminated body is described. First, the case where the polymer film containing a polyimide resin is a single layer film of a polyimide resin will be described.
First, a method for manufacturing a wiring board in the “metal (copper) layer / polyimide resin layer” laminate will be described. First, a resist film is formed on a copper thin film, and the resist film in a portion where a circuit is to be formed is removed by exposure and etching. Next, a circuit is formed by a pattern plating method using electrolytic copper using a portion where the sputtered copper thin film is exposed as a feeding electrode. Next, the resist portion is removed, and unnecessary portions of the copper thin film layer are removed by etching to form a circuit.

  The case of the “metal layer / polyimide resin layer / metal layer” laminate will be described. In the first method for manufacturing a printed wiring board, first, a via hole penetrating the laminate is formed. The via hole is formed by a drilling method using a carbon dioxide laser, a UV-YAG laser, punching, drilling, or the like. When forming a small via hole, a drilling method using a laser is preferably used. After the via hole is formed, a desmear process is performed to remove smear mainly composed of a polyimide decomposition product and heat-generated carbide in and around the via hole. Next, a palladium catalyst is supported and electroless plated copper is applied. Further, a resist film is formed, and the resist film in a portion where a circuit is to be formed is removed by exposure and development. Next, using the portion where the electroless plating layer is exposed as a feeding electrode, pattern plating with electrolytic copper is performed to form a circuit. Next, the resist portion is removed, and unnecessary portions of the electroless plating layer are removed by etching to form a circuit.

  In the second printed wiring board method, first, a via hole penetrating through a laminate composed of “metal layer / polyimide resin layer / metal layer” is formed. Next, similarly to the above, an electroless plated copper layer is formed through a desmear and catalyst supporting step. Next, panel plating is performed with electrolytically plated copper, and both sides are electrically connected by via holes. Next, a resist film is formed on the surface of the electrolytic copper plating layer, and the resist film where the circuit is not formed is removed by exposure and development. Next, an unnecessary metal layer is removed by etching to form a circuit.

  When a printed wiring board is manufactured using a laminate having a three-layer structure composed of “metal layer / polyimide resin layer / adhesive layer”, the adhesive layer is first laminated to face the inner layer substrate having the inner layer circuit. Next, a via hole penetrating the laminate is formed by a laser, desmearing is performed, a catalyst is loaded, and a circuit is formed by the same method as described above.

  When manufacturing a printed wiring board using a “metal layer / polyimide resin layer / copper foil layer” laminate, a via hole penetrating the metal copper foil through the metal layer and the polyimide layer is formed. A circuit is formed by the same method as described above.

  In the method for producing a printed wiring board of the present invention, it is possible to appropriately select a construction method and process conditions according to the necessity required from the specifications of the desired printed wiring board, etc., and to combine other known techniques. All are included in the category of the method for producing a printed wiring board of the present invention.

  That is, the via hole formation can be performed using a known carbon dioxide laser, UV-YAG laser, excimer laser, etc., and the desmear process is a wet process using permanganate, an organic alkaline solution, etc. The dry process used can be applied. Further, as the type of electroless plating, chemical plating using the catalytic action of a noble metal such as palladium, and further, as the type of metal to be deposited, copper, nickel, gold or the like can be used. Furthermore, a liquid resist, a dry film resist, or the like can be applied as the resist, and a dry film resist excellent in handleability can be preferably used. In addition, the etching for removing the power feeding layer when forming a circuit by the semi-additive method is appropriately selected depending on the type of electroless plating used in the process. When the electroless plating is copper, sulfuric acid / hydrogen peroxide, ammonium persulfate / A sulfuric acid-based etchant is preferably used, and when the electroless plating is nickel, gold or the like, it is also preferable to use an etchant that can selectively etch them.

  Next, "polymer film including a polyimide resin layer" is a polyamideimide resin, a polyetherimide resin, a polyamide resin, an aromatic polyester resin, a polycarbonate resin, a polyacetal resin, a polysulfone resin, a polyethersulfone resin, a polyethylene terephthalate resin, A case of a laminate in which a thermoplastic polyimide resin is provided on one or both sides of a phenylene ether resin, a polyolefin resin, a polyarylate resin, a liquid crystal polymer, and an epoxy resin will be described. Here, as a specific example, a method for manufacturing a laminate using a thermoplastic polyimide resin and a non-thermoplastic polyimide resin will be described. Of course, the thermoplastic polyimide resin material described below is characterized by containing an organic thiol derivative, but as already mentioned, such an organic thiol derivative is internally added to the thermoplastic polyimide resin in the form of various laminates. It may be added, or may be added in the form of performing surface treatment.

  One example of the configuration of the laminate according to the present invention is “metal layer / thermoplastic polyimide layer / non-thermoplastic polyimide layer”. Another structural example is a laminate composed of “metal layer / thermoplastic polyimide layer / non-thermoplastic polyimide layer / thermoplastic polyimide layer / metal layer”. For example, the former is used for a single-sided flexible printed wiring board, and the latter is used for a double-sided flexible printed wiring board.

  For example, the following method is used for the former production. First, a polyamic acid solution of a thermoplastic polyimide precursor is cast-coated on a non-thermoplastic polyimide film, and imidization and solvent drying are performed by a thermal cure method or a chemical cure method to form a layer made of a thermoplastic polyimide resin. . If the thermoplastic polyimide exhibits solvent solubility, after obtaining the thermoplastic polyimide resin in powder, fiber, or film form, apply the thermoplastic polyimide solution dissolved in the solvent onto the non-thermoplastic polyimide film. It is also possible to dry the solvent to form a thermoplastic polyimide resin layer. The thickness of the thermoplastic polyimide layer in the laminate according to the present invention is thin in order to take advantage of the physical properties of a non-thermoplastic polyimide film having various excellent properties such as low thermal expansion, heat resistance, and electrical characteristics as a circuit board. Is preferred. That is, the thickness of the thermoplastic polyimide layer is preferably thinner than that of the non-thermoplastic polyimide film, and the thickness of the thermoplastic polyimide layer is 1/2 or less, more preferably 1/5 or less of the non-thermoplastic polyimide layer. Some are more preferable.

  A laminate comprising “metal thin film layer / thermoplastic polyimide layer / non-thermoplastic polyimide layer / copper foil layer” is also preferably used for the purpose of the present invention. Here, the copper foil may be formed by directly bonding the copper foil with the unevenness formed thereon, or may be in a form in which the copper foil is bonded with an appropriate adhesive. As a method of laminating the polyimide film and the copper foil via an adhesive, a known method such as heat lamination or heat press can be used.

A laminate comprising “metal thin film / thermoplastic polyimide layer / non-thermoplastic polyimide layer / adhesive layer” is also preferably used for the purpose of the present invention. For the adhesive layer, an ordinary adhesive resin is used, and a known technique can be applied as long as it has an appropriate resin flowability and can realize strong adhesiveness. The resin used for the adhesive layer can be roughly divided into two types: a heat-fusible adhesive using a thermoplastic resin and a curable adhesive using a curing reaction of a thermosetting resin. As an adhesive used in the laminate of the present invention, polyimide resin, epoxy resin system, cyanate ester resin system, from the viewpoint of adhesiveness, workability, heat resistance, flexibility, dimensional stability, low dielectric properties, price, etc. Or what blended and used these can also be used preferably.
Regarding the method for producing a printed wiring board using a laminate using a thermoplastic polyimide resin and a non-thermoplastic polyimide resin as described above, the “metal layer / polyimide layer” and “metal layer / polyimide layer / metal” already described. The same method as the method for manufacturing a wiring board using a configuration such as “layer”, “metal layer / polyimide layer / metal copper foil layer”, “metal layer / polyimide layer / adhesive layer” can be applied.
As mentioned above, although the manufacturing method of the printed wiring board using the various laminated bodies of this invention was described, normal manufacturing processes, such as a desmear process and an electroless-plating process, can be applied by using the laminated body of this invention, and a line / High-density circuit formation with a space of 20 μm / 20 μm or less is possible, and a printed wiring board having excellent adhesion and high reliability can be obtained.

  EXAMPLES The effects of the present invention will be specifically described with reference to the following examples. However, the present invention is not limited to the following examples, and those skilled in the art will recognize various effects without departing from the scope of the present invention. Changes, modifications, and alterations can be made. In addition, preparation of the non-thermoplastic polyimide resin in an Example, preparation of a thermoplastic polyimide film, organic thiol compound, preparation of a laminated body, synthesis | combination / preparation of an adhesive layer, lamination | stacking, various measurement and evaluation were performed with the following method. .

(Non-thermoplastic polyimide film-A)
90 g of a 17 wt% DMF (N, N-dimethylformamide) solution of polyamic acid prepared by synthesizing pyromellitic dianhydride / 4,4′-diaminodiphenyl ether / p-phenylenediamine in a molar ratio of 4/3/1 Then, a conversion agent consisting of 17 g of acetic anhydride and 2 g of isoquinoline was mixed and stirred, and after defoaming by centrifugation, cast-coated on an aluminum foil at a thickness of 700 μm. The process from stirring to defoaming was performed while cooling to 0 ° C. The laminate of the aluminum foil and the polyamic acid solution was heated at 110 ° C. for 4 minutes to obtain a gel film having self-supporting properties. This gel film had a residual volatile content of 30 wt% and an imidization ratio of 90%. This gel film was peeled off from the aluminum foil and fixed to the frame. This gel film was heated at 300 ° C., 400 ° C., and 500 ° C. for 1 minute each to produce a polyimide film having a thickness of 25 μm.

(Non-thermoplastic polyimide film-B)
A polyimide film was prepared in the same manner as in Preparation Method-A, except that pyromellitic dianhydride / 4,4′-diaminodiphenyl ether was synthesized at a molar ratio of 1/1.

(Non-thermoplastic polyimide film-C)
3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride / p-phenylenebis (trimellitic acid monoester anhydride) / p-phenylenediamine / 4,4′-diaminodiphenyl ether in a molar ratio of 4 A polyimide film was prepared in the same manner as in Preparation Method-A, except that a 17 wt% DMAc (N, N-dimethylacetamide) solution of polyamic acid synthesized at a ratio of / 5/7/2 was used.

(Thermoplastic polyimide precursor-X)
An example of a method for producing a polyamic acid that is a precursor of a thermoplastic polyimide resin will be described below. First, 0.30 mol of 1,2-bis [2- (4-aminophenoxy) ethoxy] ethane (hereinafter referred to as DA3EG) and 2,2′-bis [4- (4-aminophenoxy) phenyl] propane (hereinafter referred to as DA3EG). And 0.70 mol of BAPP) were dissolved in N, N-dimethylformamide (hereinafter referred to as DMF). While stirring this DMF solution, 0.83 mol of 3,3 ′, 4,4′-ethylene glycol dibenzoate tetracarboxylic dianhydride (hereinafter referred to as TMEG) and 3,3 ′, 4,4′-benzophenone tetracarboxylic 0.17 mol of acid dianhydride (hereinafter referred to as BTDA) was added. Then, the DMF solution of polyamic acid having a solid concentration of 20 wt% was obtained by stirring at about 25 ° C. for about 1 hour.

(Thermoplastic polyimide precursor-Y)
BAPP is uniformly dissolved in DMF, and while stirring, the molar ratio of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and ethylenebis (trimellitic acid monoester anhydride) is 4: 1 and Acid dianhydride and diamine were added so as to be equimolar and stirred for about 1 hour to obtain a DMF solution of a solid content concentration of 20 wt% polyamic acid.

(Thermoplastic polyimide precursor-Z)
1,3-bis (3-aminophenoxy) benzene and 3,3′-dihydroxybenzidine are dissolved in DMF at a molar ratio of 4: 1 and 4,4 ′-(4,4′-isopropylidenediphenoxy is stirred with stirring. ) Bis (phthalic anhydride) was added so that the acid dianhydride and diamine were equimolar and stirred for about 1 hour to obtain a DMF solution of a solid content concentration of 20 wt% polyamic acid.

(Organic thiol derivative)
The following reagents manufactured by Aldrich were used as the organic thiol compound. As monothiols, 2-marker pyridine (abbreviation: MPY), 2-marker pyrimidine (abbreviation: MPM), 2-marker benzoimidazole (abbreviation: MBI), 2-marker benzothiazole (abbreviation: MBT) ) Was used. Examples of dithiols include 2,5-dimarkapt-1,3,4-thiadiazole (abbreviation: DMT), 2,5-dimarkapt-1,3,4-thiadiazole, dipotassium salt (abbreviation: DMTN), 2- Four types of marker-peptidyl ether (abbreviation: DME) and 2-marker-ethylsulfide (abbreviation: DMES) were used. Furthermore, the following six triazine thiol compounds, trithiocyanuric acid (abbreviation: TT), trithiocyanuric acid monosodium salt (abbreviation: TTN), 6-dibutylamino-1, 3,5 triazine, manufactured by Sankyo Kasei Co., Ltd. Dithiol (abbreviation: DB), 6-dibutylamino-1,3,5 triazine dithiol monosodium salt (abbreviation: DBN), 6-anilino-1, 3,5, triazinethiol (abbreviation: AF), 6 anilino-1 3,5, triazine thiol monosodium salt (abbreviation: AFN) was used.

(Production of laminate)
Using the above non-thermoplastic polyimide film (A) as a core film, a DMF solution of polyamic acid, which is a precursor of thermoplastic polyimide prepared by production method X, Y, Z on both sides or one side, is used with a gravure coater. And applied.
After coating, solvent drying or polyimidic acid imidation was performed by heat treatment, and a laminated polyimide film composed of a non-thermoplastic polyimide layer and a thermoplastic polyimide layer was produced at a final heating temperature of 390 ° C. Films with different thicknesses of the thermoplastic polyimide layer were obtained by changing the coating amount. For example, when the non-thermoplastic polyimide film is A and a thermoplastic polyimide layer prepared by the X method is provided only on one side, X / A and both sides are provided with the thermoplastic polyimide layer prepared by the X method. X / A / X, X / A / Cu, etc. when one side is a thermoplastic polyimide layer and the other side is a copper foil.
X / A / Cu is cast coated with polyamic acid, which is a precursor of three types of non-thermoplastic polyimide, on the mat surface of 18 μm rolled copper foil (trade name BHY-22B-T, manufactured by Japan Energy). Then, it was dried at a final drying temperature of 500 ° C., and a DMF solution of polyamic acid, which is a precursor of the thermoplastic polyimide resin produced by the above production method X, Y, or Z, was applied. After coating, the solvent was dried by heat treatment, and the polyamic acid was imidized, followed by heating at a final heating temperature of 390 ° C.

(Adhesive layer)
Under a nitrogen atmosphere, 1 equivalent of bis {4- (3-aminophenoxy) phenyl} sulfone (hereinafter referred to as BAPS-M) was dissolved in N, N-dimethylformamide (hereinafter referred to as DMF). The solution was stirred while cooling, and 1 equivalent of 4,4 ′-(4,4′-isopropylidenediphenoxy) bis (phthalic anhydride) (hereinafter referred to as BPADA) was dissolved and polymerized to obtain a solid content concentration of 30% by weight. A polyamic acid polymer solution was obtained. This polyamic acid solution was heated at 200 ° C. for 180 minutes under a reduced pressure of 665 Pa to obtain a solid thermoplastic polyimide resin. The polyimide resin obtained above and a novolak epoxy resin (Epicoat 1032H60: manufactured by Yuka Shell Co., Ltd.) and 4,4′-diaminodiphenyl sulfone (hereinafter referred to as 4,4′-DDS) have a weight ratio of 70 / The mixture was mixed to 30/9 and dissolved in dioxolane so that the solid concentration was 20% by weight to obtain an adhesive solution. The obtained adhesive solution was applied to the polyimide film surface of the laminate obtained by the above method so that the thickness after drying was 12.5 μm, and dried at 170 ° C. for 2 minutes to form an adhesive layer. Obtained. Next, an inner-layer circuit board is produced from a glass epoxy copper-clad laminate having a copper foil of 12 μm, and the laminate obtained by the above method is subjected to vacuum pressing at a temperature of 200 ° C., a hot plate pressure of 3 MPa, a pressing time of 2 hours, Condition It laminated | stacked and hardened | cured on the inner-layer circuit board on the conditions of 1 KPa.

(Formation of metal layer)
Formation of the metal layer on the polyimide film produced by the above method was performed by the following method using a sputtering apparatus NSP-6 manufactured by Showa Vacuum.
A polymer film is set on a jig and the vacuum chamber is closed. The substrate (polymer film) is evacuated to 6 × 10 ⁻⁴ Pa or less while being heated with a lamp heater while revolving. Thereafter, argon gas is introduced to 0.35 Pa, and nickel and then copper are sputtered by DC sputtering. Both DC powers were sputtered at 200W. The film formation speed was 7 nm / min for nickel and 11 nm / min for copper, and the film formation thickness was controlled by adjusting the film formation time.

(Measurement of adhesive strength)
IPC-TM-650-method. According to 2.4.9, measurement was performed at a pattern width of 3 mm, a peeling angle of 90 degrees, and a peeling speed of 50 mm / min.
(Pressure cooker test)
In order to measure the stability of the adhesive strength against the environment, a pressure cooker test was conducted under the conditions of 121 ° C., 100% RH, 96 hours.

(Measurement of surface roughness)
The surface roughness and Rz (10-point average roughness) of the surface of the thermoplastic polyimide resin were measured using a New View 5030 system manufactured by ZYGO.
(Measurement condition)
Objective lens: 50x Mirau Image zoom: 2 FDA Res: Normal
Analysis conditions:
Remove: Cylinder Filter: High Pass
Filter lower limit opening diameter (Filter Low Waven): 0.002mm

(Measurement of average linear expansion coefficient)
The average thermal expansion coefficient was measured using TMA-50 (trade name, manufactured by Shimadzu Corporation) under the following conditions, and the average thermal expansion coefficient between 100 ° C. and 200 ° C. in the measurement result was defined as the thermal expansion coefficient of the sample. .
Measurement method: Tensile mode (adjusted so that the load applied to the sample is 0 g)
Temperature increase rate: 10 ° C./min Measurement range: 30 ° C. to 300 ° C.
(Examples 1-18)
Six kinds of triazine thiol derivatives (TT, TTN, AF, AFN, DB, DBN) are added to the polyimide resin in a DMF solution of polyamic acid produced by the manufacturing methods A, B, and C on the surface of the aluminum foil in a weight ratio of 0. The polyimide film was manufactured by a method of adding 1%, and applying, heat-treating after peeling. The thickness was 25 μm. For comparison, a polyimide film to which no triazine thiol was added was prepared. A metal layer composed of two layers of a Ni underlayer 5 nm and a Cu layer 200 nm was formed on these samples by sputtering. Next, electroless plating was performed under the following conditions. The specific electroless plating conditions are as follows, and the process conditions are in accordance with the electroless plating process of Atotech.
<Electroless plating conditions>

(※) （アトテックジャパン株式会社製）
続いて、電解銅メッキを行い厚さ８μｍの銅層を形成し、その常温での接着強度、プレッシャークッカー試験後の接着強度を測定した。その結果を表３にしめす。常温での接着強度はいずれも６Ｎ／ｃｍ以上の優れた接着強度を示した。また、ＰＣＴ試験後の接着強度も４Ｎ／ｃｍであり優れた特性を示した。

(*) (Atotech Japan Co., Ltd.)
Subsequently, electrolytic copper plating was performed to form a copper layer having a thickness of 8 μm, and the adhesive strength at room temperature and the adhesive strength after the pressure cooker test were measured. The results are shown in Table 3. The adhesive strength at room temperature showed excellent adhesive strength of 6 N / cm or more. Moreover, the adhesive strength after the PCT test was 4 N / cm, indicating excellent properties.

(Examples 19 to 36)
Six kinds of triazine thiol derivatives (TT, TTN, AF, AFN, DB, DBN) are added to the polyimide resin in a DMF solution of polyamic acid produced by the production methods X, Y, and Z on the surface of the aluminum foil in a weight ratio of 0. A thermoplastic film was produced by a method of adding 1%, heat treatment after application, peeling after addition. The thickness of the thermoplastic polyimide was 25 μm. A metal layer composed of two layers of a Ni underlayer 5 nm and a Cu layer 200 nm was formed on these samples by sputtering. For comparison, a thermoplastic polyimide not added with triazine thiol was prepared. These samples were electroless plated. This is the same as the specific example 1 of electroless plating. Subsequently, electrolytic copper plating was performed to form a copper layer having a thickness of 8 μm, and the adhesive strength at room temperature and the adhesive strength after the pressure cooker test were measured. The results are shown in Table 4. The adhesive strength at room temperature showed excellent adhesive strength of 9 N / cm or more. Moreover, the adhesive strength after the PCT test was 6 N / cm, indicating excellent characteristics.

(Examples 37 to 44)
Eight kinds of organic thiol compounds (MPY, MPM, MBI, MBT, DMT, DMTN, DME, DMES) were added to the amount of polyimide resin by weight in the DMF solution of polyamic acid produced by the production method X on the aluminum foil surface. It added so that it might become 0.1%, and the thermoplastic film was manufactured by the method of heat-processing after application | coating and peeling after addition. Thereafter, formation of a sputtering layer and copper plating were performed in the same manner as in Example 1, and the adhesive strength was measured. The results are shown in Table 5. The adhesive strength with thiol derivatives was 7 N / cm or higher, and the adhesive strength with dithiol derivatives was 9 N / cm or higher. Moreover, the adhesive strength after the PCT test was 4 N / cm and 5 N / cm or more, respectively, confirming the usefulness of the present invention.

(Examples 45-56)
Two types of triazine thiol derivatives (TT, DB) are added to the DMF solution of polyamic acid produced by the preparation method X on the aluminum foil surface in various amounts with respect to the amount of the polyimide resin, and after addition, heat treatment after coating and peeling. A thermoplastic film was produced by the method described above. The thickness of the thermoplastic polyimide was 25 μm.
Next, in the same manner as in Example 1, the formation of the sputtering layer and then the copper plating treatment were performed, and the adhesive strength at room temperature and the adhesive strength after the pressure cooker test were measured. The results are shown in Table 6. From this result, the addition amount is suitably 10% or less, and the effect of the present invention can be recognized even with the addition amount of 0.001%.

(Examples 57 to 65)
Add 2g of triazine thiol sodium salt (TTN, DBN, AFN) to the cleaner conditioner solution (the one used in the table electroless plating process of Example 1) from the thermoplastic polyimide resin film produced by the production methods X, Y, Z Surface treatment was performed by dipping in the solution. Thereafter, formation of a sputtering layer and copper plating treatment were performed, and the adhesive strength was measured. The results are shown in Table 7. From this result, it was found that even the surface treatment method as shown in the present example shows a sufficient adhesive improvement effect.

(Examples 66 to 74)
The thermoplastic polyimide resin film produced by the production methods X, Y, and Z was immersed in a 0.2% DMF solution of triazine thiol sodium (TT, DB, AF) and subjected to surface treatment. Thereafter, a sputtering layer was formed and copper plating was applied in the same manner as in Example 1, and the adhesive strength was measured. The results are shown in Table 8. From this result, it was found that even the surface treatment method as shown in the present example shows a sufficient adhesive improvement effect.

(Examples 75 to 78)
As a typical core film material, four types of commercially available films, polyamide imide (Mitsubishi Kasei Co., Ltd. Torlon), polyether imide (GE Co., Ultem), liquid crystal polymer (Nippon Steel Chemical Co., Ltd., Bexter) , Aromatic polyester (Sumitomo Chemical Co., Ltd., S200) (film thickness is 25 μm), and the polyamic acid solution prepared by the preparation method Z on the film is 1% by weight with respect to the polyimide composition. Thus, the solution which added DB was apply | coated so that the obtained thermoplastic polyimide resin layer might be set to 4 micrometers, and the laminated body was produced.
The surface of the thermoplastic polyimide film Z of the obtained sample was formed with a sputtering layer and a copper plating film by the same method as in Example 1, and the adhesive strength was measured. The results are shown in Table 9. The adhesive strength at room temperature showed excellent adhesive strength of 9 N / cm or more. Moreover, the adhesive strength after the PCT test was 6 N / cm, indicating excellent characteristics.

(Examples 79 to 81)
Non-thermoplastic polyimide film, manufactured by Kaneka Chemical Co., Ltd. (Apical AH, NPI, HP (thickness 25 μm)) was used, and thermoplastic resin X (DB was added to the polyimide composition in a weight ratio of 1% on one side thereof. A sample was prepared by coating (composition thickness: 4 μm). Using this sample, electroless plating and electrolytic plating were performed in the same manner as described in Example 1.
The results are shown in Table 10. Both have excellent adhesive strength of 10 N / cm or more, and the average thermal linear expansion coefficient (ppm / ° C., measurement range: 25 ° C. to 150 ° C.) of the substrate, which is an important characteristic for circuit boards, is also 18 ppm / ° C. or less. And showed excellent characteristics.

(Example 82)
A laminate having a configuration of Y / HP / Y (Y is 4 μm, HP is 25 μm) is prepared, and then surface treatment of the thermoplastic polyimide resin with triazine thiol (DB) is performed in the same manner as in Example 66. A sputtering layer was formed. Using this laminate, a circuit was formed by the following method.
First, a via hole penetrating the laminate having an inner diameter of 30 μm was formed using a UV-YAG laser, and the smear removal of the via hole was performed by permanganate desmear treatment. The desmear treatment was performed using a permanganate desmear system manufactured by Atotech Co., Ltd. shown in the table below.

(※) （アトテックジャパン株式会社製）
次に、無電解めっきを行いビアホール内部に銅めっき層を形成した。さらに、液状感光性めっきレジスト（日本合成ゴム（株）社製、ＴＨＢ３２０Ｐ）をコーティングし、次いで高圧水銀灯を用いてマスク露光を行い、ライン／スペースが１５／１５のレジストパターンを形成した。続いて、電解銅めっきを行って、無電解銅めっき皮膜が露出する部分の表面に、銅回路を形成した。電解銅めっきは１０％硫酸中で３０秒間予備洗浄し、次に室温中で４０分間めっきを行なった。電流密度は２Ａ／ｄｍ²である。電解銅膜の厚さは１０μｍとした。次にアルカリ型の剥離液を用いてめっきレジストを剥離し、硫酸／過酸化水素系エッチャントで無電解銅めっき層を除去しプリント配線板を得た。
得られたプリント配線板は設計値通りのライン／スペースを有していた。また、回路パターンは９Ｎ／ｃｍの強さで強固に接着していた。

(*) (Atotech Japan Co., Ltd.)
Next, electroless plating was performed to form a copper plating layer inside the via hole. Further, a liquid photosensitive plating resist (manufactured by Nippon Synthetic Rubber Co., Ltd., THB320P) was coated, followed by mask exposure using a high-pressure mercury lamp to form a resist pattern with a line / space of 15/15. Subsequently, electrolytic copper plating was performed to form a copper circuit on the surface of the portion where the electroless copper plating film was exposed. The electrolytic copper plating was pre-cleaned in 10% sulfuric acid for 30 seconds and then plated at room temperature for 40 minutes. The current density is 2 A / dm ² . The thickness of the electrolytic copper film was 10 μm. Next, the plating resist was stripped using an alkaline stripping solution, and the electroless copper plating layer was removed with a sulfuric acid / hydrogen peroxide-based etchant to obtain a printed wiring board.
The obtained printed wiring board had a line / space as designed. The circuit pattern was firmly bonded with a strength of 9 N / cm.

(Example 83)
First, a laminate having a configuration of X / HP / Cu (X is 1 μm, AH is 25 μm, and copper foil is 15 μm) was prepared. A surface treatment of X with triazine thiol (TT) was performed in the same manner as in Example 66, and a sputtering layer was formed on X.
Using this laminate, a circuit was formed by the following method.
Using a UV laser from the thermoplastic polyimide resin layer side, a via hole that penetrates the thermoplastic polyimide resin layer and the non-thermoplastic polyimide film layer and reaches the copper foil was formed. Subsequently, smear removal of the via hole was performed by permanganate desmear treatment, and electroless copper plating and electrolytic copper plating were further performed. Next, a dry film resist (Asahi Kasei Dry Resist AQ) is pasted on the copper layers on both sides, exposed and developed, and a circuit of L / S = 20/20 μm is formed on the thermoplastic polyimide resin surface side by a normal subtractive method. The copper foil side formed a 100/100 μm circuit. An aqueous ferric chloride solution was used as an etching solution.
The obtained printed wiring board had lines / spaces as designed, and the circuit pattern was firmly bonded with a strength of 10 N / cm.

(Example 84)
A laminate was produced by applying the polyamic acid solution produced by the production method Y to one surface of the non-thermoplastic polyimide film HP having a thickness of 12.5 μm produced by the polyimide film production method C. The thickness of the thermoplastic polyimide film is 3 μm. Next, an adhesive layer (12 μm) was applied to the non-thermoplastic polyimide film side to obtain a laminate having a configuration of “thermoplastic polyimide layer / non-thermoplastic polyimide layer / adhesive layer”. This laminate was laminated and cured on an inner layer circuit board made from a glass epoxy copper clad laminate. The laminating method is as described above. Next, the surface of the thermoplastic polyimide resin was treated with triazine thiol (TT) in the same manner as in Example 66, and a sputtering layer was formed on the surface by the same method as in the prior art.

Next, a via hole that reaches the inner layer circuit with an inner diameter of 30 μm is formed using a UV-YAG laser, smear removal of the via hole is performed by permanganate desmear treatment, and an electroless copper plating layer is formed inside the hole by an electroless plating method. Formed. Next, a liquid photosensitive plating resist (manufactured by Nippon Synthetic Rubber Co., Ltd., THB320P) was coated, followed by mask exposure using a high pressure mercury lamp to form a resist pattern with a line / space of 15/15. Subsequently, electrolytic copper plating was performed to form a copper circuit on the surface of the portion where the electroless copper plating film was exposed. The electrolytic copper plating was pre-cleaned in 10% sulfuric acid for 30 seconds and then plated at room temperature for 40 minutes. The current density is 2 A / dm ² . The thickness of the electrolytic copper film was 10 μm. Next, the plating resist was stripped using an alkaline stripping solution, and the electroless copper plating layer was removed with a sulfuric acid / hydrogen peroxide-based etchant to obtain a printed wiring board.
The obtained printed wiring board had a line / space as designed, and the circuit pattern was firmly bonded with a strength of 10 N / cm.

  The present invention is a method for producing a laminate comprising a polymer film containing a polyimide resin and a metal film, and a printed wiring board using the laminate, and has a high density with excellent adhesion strength on a smooth polymer film surface. Therefore, it can be suitably used for electronic materials such as high-density flexible printed wiring boards and build-up wiring boards.

Claims (10)

A laminate comprising a polymer film containing at least an organic thiol compound and a polyimide resin, and a metal thin film formed on at least one surface thereof by a physical method. 2. The laminate according to claim 1, wherein the physical method is at least one method selected from a vapor deposition method, a sputtering method, and an ion plating method. The laminate according to claim 1, wherein the organic thiol compound is an organic dithiol compound and / or an organic trithiol compound. The laminate according to claim 3, wherein the organic dithiol compound and / or the organic trithiol compound is a triazine thiol derivative. The laminate according to any one of claims 1 to 4, wherein the polyimide resin is a thermoplastic resin. The polymer film containing the polyimide resin is a non-thermoplastic polyimide resin, polyamideimide resin, polyetherimide resin, polyamide resin, aromatic polyester resin, polycarbonate resin, polyacetal resin, polysulfone resin, polyethersulfone resin, polyethylene terephthalate resin. A film comprising a thermoplastic polyimide resin layer provided on one or both sides of a film made of a resin selected from phenylene ether resin, polyolefin resin, polyarylate resin, liquid crystal polymer, and epoxy resin. The laminate according to any one of the above. The thermoplastic polyimide resin is represented by the following general formula (1)

(In the formula, A and B are tetravalent organic groups, X and Y are divalent organic groups, m is 0 ≦ m ≦ 1, n is a value in the range of 0 ≦ n ≦ 1, and m + n = 1. And k is an arbitrary integer). A laminate obtained by using the thermoplastic polyimide resin material according to any one of claims 1 to 6). A and B in the general formula (1) are groups (1)

(A in the formula may be the same or different, and B may be the same or different).
The laminate according to claim 7, wherein the laminate is at least one selected from the group consisting of: X and Y in the general formula (1) are the following general formula (3)

(X in the formula may be the same or different, and Y may be the same or different).
The laminate according to claim 7 or 8, which is at least one selected from the group consisting of: The manufacturing method of the printed wiring board formed using the laminated body of Claims 1-9.