JP4288671B2 - Polyamideimide resin, methoxysilyl group-containing silane-modified polyamideimide resin, polyamideimide resin composition, cured film and metal foil laminate - Google Patents

Description

  The present invention cures a polyamideimide resin, a methoxysilyl group-containing silane-modified polyamideimide resin, a polyamideimide resin composition containing the polyamideimide resin or a methoxysilyl group-containing silane-modified polyamideimide resin resin, and the polyamideimide resin composition. It is related with the metal foil laminated body obtained by using the cured film obtained by this, and the said polyamide-imide resin composition.

  In recent years, downsizing and increasing the density of circuit boards used in electrical appliances and electronic devices have been demanded due to miniaturization of internal components accompanying the reduction in the thickness and size of electrical appliances and electronic devices. In order to realize miniaturization and high density of a circuit, a material excellent in various physical properties such as electrical properties, for example, heat resistance, insulation, low curling property, adhesion to copper foil, and the like is required.

Therefore, in order to improve adhesion and the like, a method using a polyamideimide resin composition (see Patent Document 1) in which an epoxy resin having a specific epoxy equivalent is mixed with a polyamide resin, or a polyamide having a specific viscosity, acid value, etc. A method using an imide resin (see Patent Document 2), a method using a trialkylamine or an alkoxylated melamine resin (see Patent Document 3), and the like have been proposed. However, in either method, sufficient adhesion and mechanical strength are obtained. Could not be achieved.

  By the way, the applicant of the present invention uses a cured film obtained by using a silane-modified polyamideimide resin whose molecular terminal is modified with alkoxysilane, while maintaining the flexibility of the polyamideimide, and has an elastic modulus and abrasion resistance superior to those of polyamideimide. However, it is desired to further improve various performances such as heat resistance, insulation, adhesion to metal foil, and low water absorption.

JP 7-238138 A Japanese Patent Laid-Open No. 7-292319 Japanese Patent Laid-Open No. 10-247422 JP 2001-240670 A

  The present invention improves the adhesion to metal foil, the low dielectric constant, and the low water absorption while maintaining the high heat resistance that is the original performance of the polyamide-imide resin. It aims at providing the polyamideimide resin which can be provided, the said resin composition, the cured film obtained using the said resin composition, and a metal foil laminated body.

  As a result of intensive studies to solve the above problems, the present inventors have found that a cured product or a metal foil laminate capable of solving the above problems can be obtained by using a specific polyamideimide resin or a resin composition thereof. The headline and the present invention were completed.

That is, the present invention is a polyamide-imide resin obtained by reacting dihydroxysiloxane (a1) and diisocyanate compound (a2) and then reacting with tricarboxylic acid anhydride (a3) , which comprises dihydroxysiloxane (a1), diisocyanate Each use ratio of the compound (a2) and the tricarboxylic acid anhydride (a3) is [number of moles of (a3)] / [number of moles of (a2) −number of moles of (a1)] = 1.0 to 2.0 A polyamide-imide resin having a carboxyl group or an acid anhydride group at the molecular end (Invention 1);
Dihydroxysiloxane (a1) is represented by the general formula (1):

(Wherein R ¹ independently represents a methylene group or phenylene group having 2 to 6 carbon atoms, R ² independently represents an alkyl group or phenyl group having 1 to 4 carbon atoms, and the number of repeating units n is 3) The polyamide-imide resin according to the first aspect of the present invention (Invention 2)
The polyamideimide resin according to the invention 1 or 2 (invention 3), wherein the amount of the dihydroxysiloxane (a1) used is 1% by weight or more and less than 95% by weight of the polyamideimide resin ;
Epoxy group-containing methoxysilane partial condensate (B) obtained by demethanol reaction of polyamideimide resin (A) according to any one of inventions 1 to 3 , epoxy alcohol (b1) and methoxysilane partial condensate (b2) And methoxysilyl group-containing silane-modified polyamideimide resin (Invention 4 );
The methoxysilyl group-containing silane-modified polyamideimide resin according to invention 5 (invention 5 ), wherein the methoxysilane partial condensate (b2) has an average number of Si atoms in the molecule of 2 to 100;
Epoxy alcohol (b1) is represented by the general formula (2):

The methoxysilyl group-containing silane-modified polyamideimide resin (Invention 6 ) according to Invention 4 or 5 , which is a compound represented by the formula (wherein m represents an integer of 1 to 10);
The methoxysilyl group-containing silane-modified polyamideimide resin according to any one of Inventions 4 to 6 , wherein the methoxysilyl group-containing silane-modified polyamideimide resin has a silica content of 1% or more and less than 30% in the cured residue ( Invention 7 );
A polyamideimide resin composition (Invention 8 ) comprising the methoxysilyl group-containing silane-modified polyamideimide resin according to any one of Inventions 4 to 7 and an organic solvent;
Furthermore, the polyamide-imide resin composition according to invention 8 comprising a filler (invention 9 );
The polyamide-imide resin composition according to invention 9 , wherein the filler is silica (invention 10 );
Invention A cured film obtained by curing the polyamideimide resin resin composition according to any one of Inventions 8 to 10 (Invention 11 );
Invention 8 polyamideimide resin composition according to any one of 1 to 10 was coated on a metal foil, and then a metal foil obtained by heat curing the laminate (Invention 12);
It is related with the metal foil laminated body of invention 12 (invention 13 ) whose heating temperature is 230 degrees C or less.

  When the polyamide-imide resin or the resin composition of the present invention is used, it retains the high heat resistance and insulation properties that are the original properties of a polyimide resin, and is excellent in adhesion to metal foil and low water absorption, and has extremely low curing shrinkage. A cured coating with little warpage can be provided. Further, by using the methoxysilyl group-containing silane-modified polyamideimide resin or the resin composition of the present invention, the water absorption can be further reduced and the dielectric constant can be lowered.

That is, according to the first aspect of the present invention, an organic solvent that can provide a cured coating that is excellent in low water absorption, has very little curing shrinkage, and does not warp while retaining the high heat resistance and insulation properties that are the original performances of the polyimide resin. It is possible to provide a polyamide-imide resin that is a raw material of a soluble polyamide-imide resin composition.
According to the second aspect of the present invention, it is possible to make it difficult to cause warpage of the obtained cured film, and it is possible to produce a polyamideimide resin at low cost.
According to the third aspect of the invention, the flexibility and water absorption of the obtained cured film can be improved.
According to the fourth aspect of the present invention, the adhesion and heat resistance can be further improved.
According to the present invention 5 , the yield of the target product can be increased.
According to the sixth aspect , the reactivity of the epoxy group-containing methoxysilane partial condensate (B) and the polyamideimide resin (A) can be improved.
According to the seventh aspect of the present invention, it is possible to improve adhesion and heat resistance, and it is possible to prevent warping when a metal foil is formed.
According to the present invention 8 , handling properties can be improved and work efficiency is improved.
According to the ninth aspect of the present invention, the linear expansion coefficient can be reduced.
According to the tenth aspect of the present invention, the linear expansion coefficient can be significantly reduced.
According to the eleventh aspect of the present invention, a cured film having a high elongation rate, flexibility, low water absorption, and low dielectric constant can be provided.
According to the present invention 12, it is possible to provide a metal foil laminate that is less likely to warp and has high adhesion to copper.
According to the thirteenth aspect of the present invention, energy efficiency is high and productivity is increased, and oxidation of the metal foil can be prevented.
Therefore, the cured film obtained from the polyamide-imide resin or the polyamide-imide resin composition of the present invention is a heat-resistant belt for copying machines and office automation equipment, coating agents for automobile parts such as engines, gaskets, air conditioners, wire coating agents, It is useful as an electrical insulating material such as a semiconductor interlayer insulating material, a coating agent for build-up substrates, resist ink, and conductive paste. Moreover, the metal foil laminated body of this invention is suitable as a copper-clad board for flexible printed circuit boards, a TAB tape, and a COF tape.

  The polyamideimide resin (A) (hereinafter referred to as component (A)) of the present invention comprises dihydroxysiloxane (a1) (hereinafter referred to as component (a1)), diisocyanate compound (a2) (hereinafter referred to as component (a2)) and It has a carboxyl group or an acid anhydride group at the molecular end obtained by reacting tricarboxylic acid anhydride (a3) (hereinafter referred to as component (a3)).

  The component (a1) is a polymer compound having an alkyl group or phenyl group directly bonded to a silicon atom and having a hydroxyl group at the molecular end of a polysiloxane having a siloxane bond as a continuous unit. As the component (a1), for example, the general formula (1):

The compound represented by these is mentioned. In the general formula (1), R ¹ is independently a methylene group or phenylene group having 2 to 6 carbon atoms, preferably a methylene group having 3 to 5 carbon atoms. Since the heat resistance of a cured film becomes favorable by making carbon number into about 2-6, it is preferable. R ² independently represents a C 1-4 alkyl group or a phenyl group, and the number of repeating units n is about 3 to 30, preferably 3 to 20. If n is smaller than 3, warpage tends to occur, and if n exceeds 30, the solubility in organic solvents tends to decrease. Specific examples of the component (a1) include α, ω-bis (2-hydroxyethyl) polydimethylsiloxane, α, ω-bis (3-hydroxypropyl) polydimethylsiloxane, α, ω-bis (4-hydroxybutyl). ) Polydimethylsiloxane, α, ω-bis (5-hydroxypentyl) polydimethylsiloxane, α, ω-bis [3- (2-hydroxyphenyl) propyl] polydimethylsiloxane, α, ω-bis [3- (4 -Hydroxyphenyl) propyl] polydimethylsiloxane and the like, and these may be used alone or in combination of two or more. Commercially available products can be used as they are. For example, α, ω-bis (3-hydroxypropyl) polydimethylsiloxane (Dow Corning Asia Co., Ltd. Painted 8579, DK X8-8579-4, Asahi Kasei Wacker Silicone Co., Ltd. ) IM-11) and the like.

  Component (a1) is used in an amount of 1 to 95% by weight, preferably 10 to 70% by weight, based on component (A). When the amount is less than 1% by weight, the flexibility of the resulting cured film tends to decrease, and when it is 95% or more, the surface of the cured film tends to have tack. Furthermore, in order to use the metal foil laminated body of this invention as a flexible printed circuit board, it is preferable that said value shall be about 20 to 60 weight%. The warpage of the metal foil laminate can be prevented by setting it to 20% by weight or more, and the occurrence of tackiness on the surface of the cured film can be prevented by setting it to 60% by weight or less.

The component (a2) used in the present invention is not particularly limited, and a known polyisocyanate compound can be used. Specifically, for example, 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-naphthalene diisocyanate, 3,3'-dimethyl-4,4'- Aromatic isocyanates such as diphenylmethane diisocyanate, p-phenylene diisocyanate, m-xylene diisocyanate, m-tetramethylxylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane Examples include aliphatic isocyanates such as diisocyanate, transcyclohexane-1,4-diisocyanate, hydrogenated m-xylene diisocyanate, and lysine diisocyanate. That. Among these, aromatic isocyanate is preferable from the viewpoint of heat resistance, and 4,4′-diphenylmethane diisocyanate and tolylene diisocyanate are particularly preferable. These may be used alone, but when used alone, the crystallinity tends to be high, so it is preferable to use two or more in combination.

  The component (a3) used in the present invention is not particularly limited as long as it is a trivalent carboxylic acid having an acid anhydride group or a derivative thereof, and a known one can be used. Specific examples include trimellitic anhydride, butane-1,2,4-tricarboxylic acid monoanhydride, naphthalene-1,2,4-tricarboxylic acid monoanhydride, and the like. If necessary, a part of the component (a3) may be pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′- Biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetra Carboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 4,4'-sulfonyldiphthalic dianhydride, m-terphenyl-3,3 ', 4,4'- Tetracarboxylic dianhydride, 4,4-oxydiphthalic dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis (2,3- or 3,4-dicarboxy Phenyl) propane dianhydride, 2,2-bis (2,3- or , 4-Dicarboxyphenyl) propane dianhydride, 2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3 , 3-Hexafluoro-2,2-bis [4- (2,3- or 3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,3-bis (3,4-dicarboxyphenyl)- 1,1,3,3-tetramethyldisiloxane dianhydride, butanetetracarboxylic dianhydride, bicyclo- [2,2,2] -oct-7-ene-2: 3: 5: 6-tetracarboxylic Aliphatic dicarboxylic acids such as tetracarboxylic dianhydrides such as acid dianhydrides, succinic acid, glutaric acid, adipic acid, azelaic acid, suberic acid, sebacic acid, decanedioic acid, dodecanedioic acid, butadiene diacid, and dimer acid acid, Sofutaru acid, terephthalic acid, phthalic acid, naphthalene dicarboxylic acid, may be substituted, such as an aromatic dicarboxylic acid such as oxydiphthalic acid. The amount used is preferably less than 10 mol% based on the total amount of the trivalent carboxylic acid having an acid anhydride group or a derivative thereof. When these usage-amounts become 10 mol% or more, the reactivity with a component (a1) and a component (a2) falls, and it exists in the tendency for workability | operativity to fall.

Component (A) is obtained by the child adopts a manufacturing method by sequential reaction method and reacted with added to the reaction system components (a3) after reacting the component (a1) and the component (a2). Na us, in the reaction of components (a1) - component (a3) is mainly the following (1) each reaction to (4) is estimated to proceed. That is, (1): the hydroxyl group present at the molecular end of component (a1) reacts with the isocyanate group of component (a2) to form a urethane bond; (2): the acid anhydride group of component (a3) and React to form an ester bond; (3): the isocyanate group of component (a2) and the acid anhydride group of component (a3) react to form an imide bond; (4): isocyanate of component (a2) It is estimated that the group reacts with the carboxylic acid group of component (a3) to form an amide bond .

The reaction rate of the constituent components in producing the component (A) is not particularly limited as long as the carboxyl group and / or the acid anhydride group substantially remain at the molecular terminal. The amount of (a1) to (a3) used is [number of moles of (a3)] / [number of moles of (a2) −number of moles of (a1)] = about 1.0 to 2.0. , Ki is possible to improve the flexibility of a cured film, [the number of moles of (a3)] / - be a = 1.01 to 1.50 [number of moles of (a2) the number of moles of (a1)] More preferred. In addition, since a softness | flexibility can be remarkably improved by the usage-amount of (a1) component being about 5-70 weight% in solid content of (A) component, it is preferable. As reaction temperature, it is about 60-180 degreeC normally. The component (A) thus obtained usually has a weight average molecular weight of about 5,000 to 100,000 (polystyrene conversion value by gel permeation chromatography).

The methoxysilyl group-containing silane-modified polyamideimide resin of the present invention is obtained by reacting the component (A) with the epoxy group-containing methoxysilane partial condensate (B) (hereinafter referred to as component (B)).

  Component (B) used in the present invention is a demethanol reaction of epoxy alcohol (b1) (hereinafter referred to as component (b1)) and methoxysilane partial condensate (b2) (hereinafter referred to as component (b2)). Obtained by.

The component (b1) is not particularly limited as long as it has an epoxy group and a hydroxyl group in the molecule, and a known component can be used. As the component (b1), the general formula (2):

(In the formula, m represents an integer of 1 to 10.) It is preferable because the flexibility of the obtained cured film can be improved. In addition, in the general formula (2), when m is 3 or more, the toxicity of the component (b1) is low, which is preferable for safety and hygiene, and the flexibility of the cured film can be remarkably improved. Particularly preferred.

As the component (b2), the general formula (3): Si (OCH ₃ ) ₄
A hydrolyzable methoxysilane monomer represented by the formula (1) can be obtained by hydrolyzing in the presence of an acid or base catalyst and water and partially condensing. The average number of Si in one molecule of the component (b2) is preferably about 2 to 100, and more preferably 3 to 8. When Si is less than 2, during the demethanol reaction with component (b1), the amount of methoxylanes that do not react and flows out of the system together with methanol tends to increase. Moreover, when it exceeds 100, the reactivity with a component (b1) tends to worsen and it becomes difficult to obtain the target (B) component.

  The proportion of component (b1) to component (b2) used is not particularly limited, but usually (equivalent of methoxy group in component (b2)) / (equivalent of hydroxyl group in component (b1)) = 1 / It is preferable to carry out demethanol reaction at a charge ratio of about 0.3 to 1 / 0.01.

  In the charging ratio, when the ratio increases, the ratio of the unreacted component (b2) tends to increase, and when the ratio decreases, the remaining unreacted component (b1) increases the heat resistance of the cured product. Since it tends to be worse, the charging ratio is more preferably 1 / 0.25 to 1 / 0.05.

  The reaction of the component (b1) and the component (b2) is carried out, for example, while charging each component and heating and distilling off methanol produced as a by-product. The reaction temperature is usually about 50 to 150 ° C, preferably 70 to 110 ° C. In addition, when the methanol removal reaction is performed at a temperature exceeding 110 ° C., the molecular weight of the reaction product is excessively increased with the condensation of the component (b2), and the viscosity tends to be increased or gelled easily. In such a case, high viscosity and gelation can be prevented by a method such as stopping the methanol removal reaction during the reaction.

  In addition, in the demethanol reaction of the component (b1) and the component (b2), a conventionally known catalyst that does not open the oxirane ring can be used for promoting the reaction. Examples of the catalyst include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, barium, strontium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, cerium, cadmium, and manganese. Metals: These metal oxides, organic acid salts, halides, alkoxides and the like. Among these, organic tin and organic acid tin are particularly preferable, and specifically, dibutyltin laurate, tin octylate and the like are effective.

  Moreover, the said reaction can also be performed in a solvent. The solvent is not particularly limited as long as it can dissolve the component (b1) and the component (b2). As such an organic solvent, for example, using an aprotic organic solvent such as N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, xylene or the like, even when the solvent remains in the cured film, This is preferable because it does not easily affect the conductivity.

  In addition, it is not necessary for all molecules constituting the component (B) to contain an epoxy group, as long as they contain an epoxy group having the above ratio. That is, the component (B) may contain an unreacted component (b2) up to about 20% by weight.

  The methoxysilyl group-containing silane-modified polyamideimide resin of the present invention is obtained by reacting the component (A) with the component (B). This reaction is a ring-opening esterification reaction of an oxirane ring mainly occurring between the carboxyl group and / or acid anhydride of the component (A) and the epoxy group of the component (B). Here, although the methoxysilyl group itself of the component (B) may be consumed by moisture or the like present in the reaction system, it usually does not participate in the ring-opening esterification reaction. Will remain 60% or more in the silane-modified polyimidesiloxane resin. In addition, it is preferable that 80% or more of the methoxysilyl groups remain, since adhesion to the metal foil can be improved and gelation can be prevented.

  The production of the methoxysilyl group-containing silane-modified polyamideimide resin is carried out by charging the components (A) and (B) and heating them to cause a ring-opening esterification reaction. The reaction temperature is usually about 40 to 130 ° C, preferably 70 to 110 ° C. If the reaction temperature is less than 40 ° C., the reaction time becomes longer, and if it exceeds 130 ° C., the condensation reaction between methoxysilyl sites, which is a side reaction, tends to proceed, both of which are not preferable. When the reaction temperature is about 40 to 130 ° C., the total reaction time is usually about 1 to 7 hours.

  The silica content in the cured residue of the methoxysilyl group-containing silane-modified polyimide siloxane resin (see below for the meaning of the cured residue) is preferably 1% or more and less than 30%. When the silica content is less than 1%, the effect of the present invention is not easily obtained. When the silica content is 30% or more, the coating layer shrinks upon curing, and the metal foil laminate is slightly warped. Tend to occur.

  In addition, it is preferable to perform the said reaction in presence of a solvent. The solvent is not particularly limited as long as it is an organic solvent that dissolves both the component (A) and the component (B). As such an organic solvent, for example, N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, cyclohexanone and the like can be used. Moreover, you may use poor solvents, such as xylene and toluene, with respect to these good solvents in the range which is 30 weight% or less of the whole solvent in the range which does not precipitate the said (A) component and component (b2).

  The method of adding and using the solvent in the reaction system is not particularly limited. Usually, the solvent added when synthesizing the component (i) (A) is used as it is. ; (Ii) The solvent added when the component (B) is synthesized from the component (b1) and the component (b2) is used as it is. And (iii) at least one selected from the three modes of (iii) added before the reaction between the component (A) and the component (B).

  Moreover, the catalyst for accelerating | stimulating reaction can be used for reaction of (A) component and (B) component. For example, tertiary amines such as 1,8-diaza-bicyclo [5.4.0] -7-undecene, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; Imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, benzimidazole; tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine, etc. Organic phosphines; tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmorpholine tetraphenylborate It can be mentioned tetraphenyl boron salts such over bets like. The catalyst is preferably used at a ratio of about 0.1 to 5 parts by weight per 100 parts by weight of component (A).

The polyamide-imide resin composition of the present invention has a use amount of the polyamide-imide resin or the methoxysilyl group-containing silane-modified polyamide-imide resin (hereinafter simply referred to as the polyamide-imide resin (A) or the methoxysilyl group). Group-containing silane-modified polyamideimide resin) and an organic solvent.
The polyamideimide resin composition containing the methoxysilyl group-containing silane-modified polyamideimide resin of the present invention contains the methoxysilyl group-containing silane-modified polyamideimide resin obtained as described above as an essential component, The silane-modified polyamideimide resin has a methoxysilyl group derived from the component (B) in its molecule. The methoxysilyl group forms a cured product condensed with each other by sol-gel reaction or demethanol condensation reaction by evaporation of a solvent, heat treatment, or reaction with moisture (humidity). Such a cured product has fine gelled silica sites (high-order network structure of siloxane bonds). Moreover, the polyamide-imide resin composition of the present invention can further contain a filler, whereby the dimensional stability of the cured film can be improved.

  The polyamide-imide resin composition of the present invention may be appropriately blended with a conventionally known polyamide-imide resin, the components (b2), (B), and the like as desired without departing from the object of the present invention. Good.

  It is appropriate that the polyamide-imide resin composition is normally in a liquid state with a curing residue of about 10 to 70% by weight. Moreover, as the solvent, for example, the solvent used in the ring-opening esterification reaction or an organic solvent such as ester, ketone, alcohol or phenol can be used. By using an organic solvent, the viscosity can be adjusted and the handleability can be improved. In addition, a solvent having poor solubility in a resin composition such as xylene or toluene can be used in combination with the solvent.

  Further, the polyamide-imide resin composition may contain at least one organic solvent of N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, and at the time of each production of the component (A) and the component (B). The total amount of the organic solvent used is preferably about 10% by weight or more in each composition. If the content is less than 10%, the polyamideimide resin composition has a high viscosity at room temperature, and the handleability tends to deteriorate.

  The content of the polyamideimide resin in the polyamideimide resin composition is not particularly limited, but it is usually preferably 20% by weight or more in the cured residue of the polyamideimide resin composition. Here, the curing residue means a solid content obtained by applying the polyamide-imide resin composition, followed by sol-gel curing or imidization and removing volatile components, and the polyamide-imide resin composition is 100 μm or less. It is a solid substance after being dried and cured at 200 ° C. for about 2 hours after coating.

  When there is a large difference in the linear expansion coefficient between the cured film obtained from the polyamideimide resin composition and the metal foil, the metal foil laminate may be warped. Therefore, it is preferable to add a conventionally known filler to the polyamideimide resin composition so that the linear expansion coefficient approaches that of the metal foil. Fillers include oxides such as carbon, silica, alumina, titania and magnesium oxide, complex oxides such as kaolin, talc and montmorillonite, carbonates such as calcium carbonate and barium carbonate, sulfates such as calcium sulfate and barium sulfate, Although titanates such as barium titanate and potassium titanate, phosphates such as tricalcium phosphate, dicalcium phosphate, and primary calcium phosphate can be used, but not limited thereto. Absent. Among these fillers, it is most preferable to use silica in consideration of the stability of the methoxysilyl group-containing silane-modified polyamideimide resin composition, the dispersibility of the filler, and the effect of suppressing warpage. Usually, the filler preferably has an average particle diameter in the range of about 0.01 μm to 5 μm. Fillers less than 0.01 μm are expensive and poor in versatility, and those exceeding 5 μm cannot be dispersed and tend to settle. In addition, since the silane-modified polyamideimide resin composition is excellent in filler dispersibility, the blending amount of the filler is not particularly limited, but the weight ratio of the filler in the cured film is preferably 90% or less. If it exceeds 90%, the flexibility of the cured film tends to be lost. In addition, the addition method of the said filler will not have a restriction | limiting in particular if it is a stage until it forms into a film using a polyamidoimide resin composition, For example, the polymerization stage of (A) component, (A) component, and (B ) May be added during the reaction with the component, or may be added during film formation.

  Further, the polyamide-imide resin composition has an organic solvent, a plasticizer, a weathering agent, an antioxidant, a heat stabilizer, a lubricant, an antistatic agent as required for various applications within a range that does not impair the effects of the present invention. Agents, brighteners, colorants, conductive agents, mold release agents, surface treatment agents, viscosity modifiers, coupling agents, and the like may be blended.

A desired metal foil laminate can be obtained by applying the polyamideimide resin composition of the present invention to a metal foil, followed by drying by heating and curing. The cured film in the metal foil laminate has a silica (SiO ₂ ) site derived from a methoxysilyl group or filler (in the case of silica) of a methoxysilyl group-containing silane-modified polyimidesiloxane resin.

  In addition, the cured film obtained from the polyamideimide resin composition of the present invention has low water absorption and high insulation, but particularly when the metal foil laminate is used for FPC, TAB, and COF, the dielectric constant at 1 kHz. Is preferably about 3.5 or less and the water absorption is less than 2%. When the dielectric constant is greater than 3.5, the cured film is too thick to obtain sufficient insulation, and when the water absorption is 2% or more, the dimensional stability is deteriorated or the metal foil laminate is obtained. May be warped.

  Examples of the metal foil used for the metal foil laminate include electrolytic copper foil, rolled copper foil, aluminum foil, and stainless steel foil. Among these, electrolytic copper foil and rolled copper foil are preferable because of their excellent conductivity, heat resistance, mechanical strength, and surface smoothness. In general, for FPC and TAB, surface-treated copper foil with an increased surface roughness of the adhesive surface of the copper foil is used for the purpose of obtaining adhesiveness with an adhesive, but a cast obtained from a polyamideimide resin composition is used. The film has extremely good adhesion to the metal foil without the use of an adhesive, and it is not necessary to roughen the surface exceptionally. The roughness is low for untreated copper foil, fine pitch, and high frequency. Adequate adhesion can be obtained even with a metal foil. Therefore, as the metal foil, it is preferable to use a copper foil having a surface roughness that is not so large, particularly a metal foil laminate having a surface roughness (Rz) of 7 μm or less, particularly Rz of 2.2 μm or less. The thickness of the metal foil is not particularly limited, but is preferably 70 μm or less, particularly preferably 20 μm or less, for use in a fine pitch substrate.

  When the polyamideimide resin composition of the present invention is dried and cured on a metal foil, it is usually preferably performed in two or more stages in order to suppress foaming due to rapid scattering of volatile components such as solvents. Therefore, the curing temperature and heating time are not particularly limited. The curing temperature is usually preferably 230 ° C. or lower because energy efficiency is high and productivity is increased, and oxidation of the metal foil can be prevented. When using a methoxysilyl group-containing silane-modified polyimidesiloxane, the amount of methanol by-produced during the sol-gel reaction of the methoxysilyl group-containing silane-modified polyimidesiloxane, the type of solvent, and the cured film It is preferable to appropriately determine the thickness in consideration of the film thickness and the like, and the first stage is preferably performed at 80 to 150 ° C. for 1 to 30 minutes mainly for the purpose of drying the solvent. Subsequently, it is heated at 130 ° C. to 230 ° C., preferably 150 ° C. or higher and lower than 210 ° C. for 1 to 180 minutes, thereby completely removing the residual solvent and completing the sol-gel curing.

  In addition, the adhesion strength of the metal foil / cured film in the metal foil laminate obtained by applying the polyamideimide resin composition to which the filler is added onto the metal foil, and drying and curing the filler constitutes the resin composition. In such a case, the linear expansion coefficient is high by applying a resin composition containing no filler on the metal foil, drying and curing, After forming a cured film having excellent adhesion to the foil, a resin composition containing a filler capable of forming a cured film having a lower linear expansion coefficient, or a conventionally known polyimide resin having a linear expansion coefficient of 30 ppm or less The disadvantage can be eliminated by applying, drying and curing. At this time, the thickness of the cured film produced from the polyamideimide resin composition is preferably 10 μm or less in order to suppress warpage of the metal foil laminate.

  In addition, the thickness of these insulating layers may be appropriately determined according to the application, but when used for FPC and TAB, the thickness of the cured film excluding the metal foil is about 3 to 100 μm, particularly 5 to 5 μm. It is preferably 50 μm.

  In a metal foil laminate in which a metal foil is bonded to one side, a double-sided metal foil laminate can be obtained by plating the polyamideimide resin layer side. As the metal plating method, a known method such as an electroless plating method, a combined method of an electroless plating method and an electrolytic plating method, a pulse plating method, a thermal melting method, a plasma method, a sputtering method, or the like can be adopted. In view of the properties, the electroless plating method and the combined use of electroless plating and electrolytic plating are particularly preferable. The electroless plating method is a method in which a metal to be a catalyst is deposited on the surface and inner wall of a substrate, and then copper or the like is deposited by an electroless plating method for plating. Moreover, the combined method of electroless plating and electrolytic plating is a method in which electroless plating is thinly deposited, and then a metal is thickened by electrolytic plating and plated. In the present invention, the plating metal is not particularly limited, and examples thereof include copper, nickel, gold, silver, platinum, tin, lead, cobalt, tungsten, molybdenum, palladium, and alloys thereof. Of these, copper is particularly preferred. Various circuit boards can be manufactured by applying a resist to the metal laminate of the present invention obtained as described above, exposing it to light, and etching the resist.

  Hereinafter, the present invention will be described more specifically with reference to production examples, examples and comparative examples. In each case,% is based on weight in principle.

Example 1 (Production of polyamideimide resin (A))
In a reaction apparatus equipped with a stirrer, a water separator, a thermometer and a nitrogen gas introduction tube, 500 g of 4,4′-diphenylmethane diisocyanate (trade name “Millionate MT” manufactured by Nippon Polyurethane Industry Co., Ltd.), α, ω-bis 691-g of (3-hydroxypropyl) polydimethylsiloxane (manufactured by Dow Corning Asia Ltd., trade name “Paintad 8579”) was charged and subjected to urethanization reaction at 60 ° C. for 2 hours. Next, 242 g of trimellitic anhydride (Mitsubishi Gas Chemical Co., Ltd.) and 1317 g of N, N-dimethylacetamide were added, and the mixture was heated to 110 ° C., dissolved, and reacted for 2 hours. Thereafter, the temperature was raised to 150 ° C. and reacted for 5 hours to obtain a polyamideimide resin solution (A1). Further, [number of moles of trimellitic anhydride] / [number of moles of diisocyanate compound−number of moles of dihydroxysiloxane] = 1.07.

Example 2 (Production of polyamideimide resin (A))
In a reaction apparatus equipped with a stirrer, a water separator, a thermometer and a nitrogen gas introduction tube, 500 g of 4,4′-diphenylmethane diisocyanate (trade name “Millionate MT” manufactured by Nippon Polyurethane Industry Co., Ltd.), α, ω-bis 704 g of [3- (2-hydroxyphenyl) propyl] polydimethylsiloxane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-22-1910”) was charged and subjected to urethanization reaction at 60 ° C. for 2 hours. Subsequently, 260 g of trimellitic anhydride (manufactured by Mitsubishi Gas Chemical Co., Inc.) and 1317 g of N, N-dimethylacetamide were added, and the mixture was heated to 110 ° C., dissolved, and reacted for 2 hours. Thereafter, the temperature was raised to 150 ° C. and reacted for 5 hours to obtain a polyamideimide resin solution (A2). Further, [number of moles of trimellitic anhydride] / [number of moles of diisocyanate compound−number of moles of dihydroxysiloxane] = 1.07.

Production Example 1 (Production of epoxy group-containing methoxysilane partial condensate (B))
In the same reactor as in Production Example 1, 1400 g of glycidol (manufactured by NOF Corporation, trade name “Epiol OH”) and tetramethoxysilane partial condensate (manufactured by Tama Chemical Co., Ltd., trade name “Methyl Silicate 51”), The average number of Si was 4) 8958 g was charged, and the temperature was raised to 90 ° C. while stirring under a nitrogen stream. Then, 2 g of dibutyltin dilaurate was added as a catalyst to react. During the reaction, the produced methanol was distilled off using a water separator, and when the amount reached about 630 g, it was cooled. It took 5 hours to cool after raising the temperature. Subsequently, about 80 g of methanol remaining in the system was removed under reduced pressure at 13 kPa for about 10 minutes. In this way, an epoxy group-containing methoxysilane partial condensate (B1) was obtained. In addition, (equivalent of methoxy group of methoxysilane partial condensate) / (equivalent of hydroxyl group of epoxy alcohol) at the time of preparation = 1 / 0.1.

Production Example 2 (Production of epoxy group-containing methoxysilane partial condensate (B))
The glycidol in Production Example 1 was changed to 2716 g of epoxy alcohol (trade name “EOA” manufactured by Kuraray Co., Ltd.), and the same reaction was performed to obtain an epoxy group-containing methoxysilane partial condensate (B2). In addition, (equivalent of methoxy group of methoxysilane partial condensate) / (equivalent of hydroxyl group of epoxy alcohol) at the time of preparation = 1 / 0.1.

Example 3 (Production of methoxysilyl group-containing silane-modified polyamideimide resin)
In the same reaction apparatus as in Example 1, 2508 g of the polyamideimide resin solution (A1) obtained in Example 1 and 57 g of the epoxy group-containing alkoxysilane partial condensate (B1) obtained in Production Example 2 were charged and the temperature was raised to 90 ° C. After warming, the reaction was allowed to proceed for 2 hours to obtain the desired methoxysilyl group-containing silane-modified polyamideimide resin solution. The resin solution has a cured residue of 52.4%, and the silica content in the cured residue is 2%.

Example 4 (Production of methoxysilyl group-containing silane-modified polyamideimide resin)
In the same reaction apparatus as in Example 1, 2817 g of the polyamideimide resin solution (A2) obtained in Example 2 and 61 g of the epoxy group-containing alkoxysilane partial condensate (B1) obtained in Production Example 2 were charged, and the temperature was raised to 90 ° C. After warming, the reaction was allowed to proceed for 2 hours to obtain the desired methoxysilyl group-containing silane-modified polyamideimide resin solution. The resin solution has a cured residue of 51.4%, and the silica content in the cured residue is 2%.

Examples 5 to 8 (Production of polyamideimide resin composition)
The polyamideimide resin solutions obtained in Examples 1 to 4 were each diluted with N, N-dimethylacetamide as shown in Table 1 to obtain a polyamideimide resin composition having a curing residue of 48.0%.

Example 9 (Production of polyamideimide resin composition)
Silica filler dispersion [silica filler (trade name “Leosil DM-30S”, average particle diameter of the filler 10 nm) of silica filler (manufactured by Tokuyama Corporation)] was added to 8 g of the methoxysilyl group-containing silane-modified polyimidesiloxane resin solution obtained in Example 3. ] Obtained by dispersing 16 g of N, N-dimethylacetamide in 56 g] to give a methoxysilyl group content of 24.49% in the cured residue and a silica filler content of 80% in the cured residue A silane-modified polyimidesiloxane resin composition was obtained.

Comparative Example 1 (Production of comparative polyamideimide resin composition)
In the same reaction apparatus as in Example 1, 1175 g of N-methyl-2-pyrrolidone, 294 g of xylene, 346 g of trimellitic anhydride and 437 g of 4,4 � -diphenylmethane diisocyanate were added and reacted at 90 ° C. for 2 hours under a nitrogen stream. I let you. Next, the nitrogen stream was stopped and the temperature was raised to 135 ° C. over 1 hour, and then the reaction was continued for 15 hours. Thereafter, the mixture was cooled and diluted with N-methyl-2-pyrrolidone / xylene = 4/1 (weight ratio) to obtain a polyamideimide resin solution having a nonvolatile content of 25%.

Examples 10 to 14 and Comparative Example 2 (Preparation of cured film)
The polyamideimide resin composition obtained in Examples 5 to 9 and the resin composition obtained in Comparative Example 1 were each coated on a glass plate with an applicator (wet 300 μm), and each coated glass plate was dried. It was put in a vessel, dried and cured stepwise at 100 ° C. for 10 minutes and then at 200 ° C. for 120 minutes, and then allowed to cool to room temperature, whereby each cured film having a thickness of 80 μm was obtained.

For the cured films obtained in Examples 10 to 14 and Comparative Example 2, the content of the portion derived from dihydroxysiloxane (a1) in the polyamideimide resin, the content of silica (SiO ₂ ) in the cured residue, and the filler The content (= filler amount / (cured residue amount + filler amount)) is shown in Table 2.

(Linear expansion coefficient and glass transition point)
The cured films (4 mm × 20 mm) obtained in Examples 10 to 14 and Comparative Example 2 were obtained from 40 ° C. to 200 ° C. using a thermomechanical analyzer (trade name “TMA120C” manufactured by Seiko Instruments Inc.). The linear expansion coefficient up to ° C. was measured. The results are shown in Table 3.

(Water absorption rate)
The measured weight after leaving the cured films (50 mm × 50 mm) obtained in Examples 10 to 14 and Comparative Example 2 in a constant temperature bath maintained at 50 ° C. for 24 hours, and then a constant temperature water bath maintained at 23 ° C. The water absorption rate was calculated from the difference from the measured weight after being immersed for 24 hours. The results are shown in Table 3.

(Dielectric constant)
The cured film (50 mm × 50 mm) obtained above was measured at a frequency of 1 kHz and a temperature of 23 ° C. using a dielectric constant / dielectric loss tangent measuring instrument (manufactured by Kitahama Manufacturing Co., Ltd.). The results are shown in Table 3.

(Dielectric constant)
The mechanical properties of the cured film (5 mm × 20 mm) obtained above were stretched by breaking the cured film at a pulling speed of 5 mm / min using a Tensilon tester (Orientec Co., Ltd., product name UCT-500). The elongation (maximum elongation) of the film until it was measured was measured. A tensile test was performed three times at 25 ° C. in the same manner. The results are shown in Table 3.

  As is apparent from Table 3, by introducing a siloxane moiety, a flexible cured film having a low water absorption rate, a low dielectric constant, and a high elongation rate was obtained (in Examples 10 and 11). Further, by introducing a siloxane moiety and further forming a silica hybrid, the water absorption and dielectric constant could be further reduced. (Examples 12 and 13). Moreover, the thermal expansion coefficient was able to be reduced significantly by containing a silica filler (the thing of Example 14).

Examples 15 to 18 and Comparative Example 3 (Formation of a metal foil laminate)
For the resin compositions obtained in Examples 5 to 8 and Comparative Example 2, electrolytic copper foil (manufactured by Furukawa Electric Co., Ltd., trade name “F2-WS”, film thickness 18 μm, surface roughness Rz = 2.1 ) With an applicator (wet 100 μm), put in a drier, and cured at 100 ° C. for 10 minutes and then at 170 ° C. for 20 minutes to obtain a metal foil laminate having a cured film thickness of 25 μm.

Example 19 (Production of metal foil laminate)
The resin solution obtained in Example 7 was coated on the same electrolytic copper foil as used in Example 15 with an applicator (wet 50 μm), placed in a drier, dried at 100 ° C. for 10 minutes, and then in Example 5. The obtained resin solution is overcoated with an applicator (wet 50 μm), placed in a drier again, and cured under conditions of 100 ° C. for 10 minutes and then 170 ° C. for 20 minutes, thereby a metal foil laminate having a cured film thickness of 25 μm. Got.

(Adhesion)
The delamination strength of each metal foil laminate obtained above was measured according to the standard of JIS C6481. The results are shown in Table 4.

(warp)
The smoothness of the metal foil laminate obtained above was evaluated visually. The evaluation results are shown in Table 4.
◯: There is no warping.
X: There is warping.

  As is apparent from Table 4, the polyamideimide resin-laminated metal foil laminates (Examples 15 and 16) into which siloxane sites were introduced showed no warpage and had an interlayer peel strength of 1.1 kg / cm. High adhesion was exhibited. In addition, the polyamideimide resin metal foil laminates (Examples 17 and 18) in which a siloxane moiety was introduced and further made into a silica hybrid were not warped and had a delamination strength of 1.4 kg / cm, more copper foil. And showed high adhesion.

Claims (13)

After dihydroxysiloxanes (a1) and the diisocyanate compound (a2) is reacted, a polyamide-imide resin obtained by reacting a tricarboxylic anhydride (a3), dihydroxysiloxanes (a1), a diisocyanate compound (a2) and tricarboxylic Each use ratio of the acid anhydride (a3) is [number of moles of (a3)] / [number of moles of (a2) −number of moles of (a1)] = 1.0 to 2.0 at the molecular terminal. Polyamideimide resin having a group or an acid anhydride group. Dihydroxysiloxane (a1) is represented by the general formula (1):

(Wherein R ¹ independently represents a methylene group or phenylene group having 2 to 6 carbon atoms, R ² independently represents an alkyl group or phenyl group having 1 to 4 carbon atoms, and the number of repeating units n is 3) The polyamideimide resin according to claim 1, which is represented by: The polyamideimide resin according to claim 1 or 2, wherein the amount of dihydroxysiloxane (a1) used is 1% by weight or more and less than 95% by weight of the polyamideimide resin. An epoxy group-containing methoxysilane partial condensate obtained by a demethanol reaction between the polyamideimide resin (A) according to any one of claims 1 to 3 and an epoxy alcohol (b1) and a methoxysilane partial condensate (b2) ( A methoxysilyl group-containing silane-modified polyamideimide resin obtained by reacting with B). The methoxysilyl group-containing silane-modified polyamideimide resin according to claim 4, wherein the methoxysilane partial condensate (b2) has an average number of Si atoms in the molecule of 2 to 100. Epoxy alcohol (b1)
General formula (2):

The methoxysilyl group-containing silane-modified polyamideimide resin according to claim 4 or 5, which is a compound represented by the formula (wherein m represents an integer of 1 to 10). The methoxysilyl group-containing silane-modified polyamideimide resin according to any one of claims 4 to 6, wherein the methoxysilyl group-containing silane-modified polyamideimide resin has a silica content of 1% or more and less than 30% in the cured residue. . A polyamide-imide resin comprising the polyamide-imide resin according to claim 1 or the methoxysilyl group-containing silane-modified polyamide-imide resin according to any one of claims 4 to 7, and an organic solvent. Composition. The polyamideimide resin composition according to claim 8, further comprising a filler. The polyamide-imide resin composition according to claim 9, wherein the filler is silica. A cured film obtained by curing the polyamideimide resin resin composition according to claim 8. The metal foil laminated body obtained by apply | coating the polyamideimide resin composition in any one of Claims 8-10 on metal foil, and then making it heat-harden. The metal foil laminate according to claim 12, wherein the heating temperature is 230 ° C or lower.