WO2011033819A1 - Method for forming polymer layer - Google Patents

Abstract

Disclosed is a method for forming a polymer layer, which comprises, sequentially in the following order, (a) a step wherein a coating liquid containing a polymer (P) that has a glass transition temperature of not more than 180˚C and a solvent (A) that dissolves the polymer (P) is applied over a supporting body, thereby forming a coating film thereon, (b) a step wherein the solvent (A) is removed from the coating film by bringing a liquid (B), which contains either water and/or an alcohol and does not dissolve the polymer (P), into contact with the coating film, and (c) a step wherein the coating film is dried. In this connection, the solvent (A) and the liquid (B) satisfy the following relation: [boiling point of solvent (A)] > [boiling point of liquid (B)]. The method for forming a polymer layer is capable of forming a polymer layer, which is free from voids, with a short drying time regardless of the boiling point of a solvent that is used for the coating liquid.

Description

Method for forming polymer layer

The present invention relates to a method for forming a polymer layer, and more particularly to a method for forming a layer to be plated or a polymer layer suitable as a lower layer thereof.

As a method for forming a polymer layer, for example, a method is known in which a polymer solution is applied on a support and the obtained coating film is heated and dried using a radiation heater or a heat transfer heater (for example, JP (See 2004-243172).
The polymer solution used when forming the polymer layer uses a high-boiling solvent from the viewpoint that it is easier to handle than a low-boiling solvent and that equipment costs are lower than when a low-boiling solvent is used. However, when such a high-boiling solvent is used, it is necessary to increase the drying temperature of the coating film or to dry it for a long time.

Moreover, there exists the following techniques as one of the techniques which raise the drying speed of a coating film.
For example, a coating film obtained by applying a solution in which a polyimide precursor is dissolved in an aprotic polar solvent is contacted with a solvent that is insoluble in the polyimide precursor and miscible with the aprotic polar solvent. A method of drying after replacing the protonic polar solvent is known (see, for example, JP-A-2001-212833).

By the way, when the drying temperature of the coating film is increased, if the heat resistance of the polymer itself is low, the polymer may be deformed by this drying temperature. Therefore, it is necessary to lower the drying temperature. However, if it takes a long time to remove the coating solvent (drying), the inner solvent is removed (dried) after the vicinity of the surface of the coating has been dried first. Voids are formed in the polymer layer, and as a result, local strength reduction may occur in the plane of the polymer layer.

Therefore, the present invention has been made in consideration of the drawbacks of the above-described conventional techniques, and an object thereof is to achieve the following object.
That is, an object of the present invention is to provide a method for forming a polymer layer, which can form a polymer layer without voids in a short drying time regardless of the boiling point of the solvent used in the coating solution.

As a result of intensive studies in view of the above problems, the present inventor has found that the above object can be achieved by the following means.
That is, in the method for forming a polymer layer of the present invention, (a) a coating solution containing a polymer P having a glass transition temperature of 180 ° C. or less and a solvent A that dissolves the polymer P is applied on a support. A step of forming a film, (b) a step of bringing the coating film into contact with a liquid B containing at least one of water and alcohol that does not dissolve the polymer P, and removing the solvent A from the coating layer; ) Drying the coating film in this order, wherein the solvent A and the liquid B satisfy the following relationship.
Boiling point of solvent A> Boiling point of liquid B

The porosity in the polymer layer obtained by the method for forming a polymer layer of the present invention is preferably 50% or less.
In the present invention, it is preferable that the boiling point of the solvent A and the glass transition temperature of the polymer P satisfy the following relationship.
Boiling point of solvent A> Glass transition temperature of polymer P-50 ° C

Furthermore, the alcohol used as the liquid B is more preferably an alcohol having 4 or less carbon atoms.
In addition, it is also a preferred embodiment that the solvent A is water-soluble.

In addition, it is also a preferred embodiment that the polymer P is a polymer containing a cyano group.
In addition, it is one of preferred embodiments that the polymer containing a cyano group is a polymer containing a cyanoalkyl group in the side chain.

4 is a graph showing the residual amount of cyclohexanone in the polymer layers obtained in Examples 1 to 3. 6 is a graph showing the residual amount of cyclohexanone in the polymer layers obtained in Example 2 and Comparative Examples 1 to 4. 6 is a graph showing the residual amount of N-ethylmorpholine in the polymer layers obtained in Examples 4 to 6 and Comparative Example 5. 6 is a graph showing the residual amount of cyclohexanone in the polymer layers obtained in Examples 7 to 9 and Comparative Example 6. 3 is a graph showing the residual amount of cyclohexanone in the polymer layers obtained in Examples 10, 11, 1, and 2. FIG. 7 is a graph showing the film strength of the polymer layers obtained in Examples 12 and 13 and Comparative Example 7.

Hereinafter, the present invention will be described in detail.
The method for forming a polymer layer according to the present invention comprises: (a) applying a coating solution containing a polymer P having a glass transition temperature of 180 ° C. or less and a solvent A that dissolves the polymer P on a support; A step of forming (hereinafter referred to as (a) step), and (b) contacting the coating film with a liquid B containing at least one of water and alcohol that does not dissolve the polymer P. A step of removing the solvent A (hereinafter referred to as (b) step), and (c) a step of drying the coating film (hereinafter referred to as (c) step) in this order. The liquid B satisfies the following relationship.
Boiling point of solvent A> Boiling point of liquid B Hereinafter, steps (a) to (c) will be described in order.

[(A) Process]
In the step (a) in the present invention, (a) a coating solution is formed by applying a coating liquid containing a polymer P having a glass transition temperature of 180 ° C. or less and a solvent A for dissolving the polymer P on a support. To do.

[Polymer P (specific polymer P) having a glass transition temperature of 180 ° C. or lower]
First, a polymer P having a glass transition temperature of 180 ° C. or lower used in this step (hereinafter referred to as a specific polymer P as appropriate) will be described.
Here, the glass transition temperature means a value obtained by measurement by the following method.
That is, by differential scanning calorimetry (DSC) measurement, the sample endotherm is measured while slowly increasing the sample temperature from −180 ° C. to 250 ° C. (1 ° C./min) to determine the glass transition temperature.
The specific polymer P used in this step may be any polymer as long as it has a glass transition temperature as described above (hereinafter, referred to as “Tg” as appropriate). Accordingly, it may be appropriately selected. The Tg of the specific polymer P is preferably in the range of −160 ° C. to 180 ° C., more preferably −30 ° C. to 150 ° C., from the viewpoint of physical properties such as heat resistance, shear stress, tensile stress, and viscosity. In the vicinity of this Tg or higher temperature range, the specific polymer P is easily deformed even in a short time. For this reason, depending on the boiling point of the solvent to be used, a void is generated, and the uniformity of the film is easily impaired. However, according to the present invention, the generation of a void can be effectively suppressed regardless of the type of the solvent.
In the case of a polymer having a Tg higher than 180 ° C., the coating solution containing this polymer can be dried at a high temperature around 180 ° C. or higher if the temperature is lower than the Tg of the polymer P. From the viewpoint of being able to be dried in a low temperature range without causing deformation of the specific polymer P, which is one of the effects of the present invention, since it is possible to cope with the application of a normal drying process. When applied to a polymer having a Tg in the range of −160 ° C. to 180 ° C., the effect is remarkable.

Here, the content of the polymer P having a glass transition temperature of 180 ° C. or higher in the coating solution used in this step may be determined by the coating method and the required film thickness after coating. On the other hand, it is preferably 1% by mass to 40% by mass, more preferably 2% by mass to 20% by mass, and further preferably 3% by mass to 10% by mass.

[Solvent A]
Next, the solvent A used in this step will be described.
The solvent A is a solvent that can dissolve the specific polymer P described above, and has a higher boiling point than the liquid B described later.
Here, dissolving the specific polymer means that after preparing a 1% solution, it can be visually confirmed that no precipitate is formed after standing at room temperature (25 ° C. in this specification) for 10 minutes. To do.

The solvent A is not particularly limited as long as it has a higher boiling point than that of the solvent B, but preferably has a boiling point of 100 ° C. or higher, more preferably 120 ° C. or higher. From the viewpoint of ease of use of a general-purpose solvent, the upper limit of the boiling point of the solvent A is preferably 350 ° C.
Further, the boiling point of the solvent A is preferably higher than [Tg-50] ° C. with respect to the glass transition temperature (Tg) of the specific polymer P from the viewpoint of easy handling and safety of the solvent. More preferably, it is in the range of −50 ° C. to + 350 ° C. with respect to the temperature.

Specific examples of the solvent A include 2-methyl-1-propanol, 1-butanol, 1-pentanol, 1-hexanol, cyclohexanol, ethylene glycol, glycerin, isopentyl alcohol, isobutyl alcohol, 1-methoxy-2 Alcohol solvents such as -propanol, 3-methyl-1-butanol, 2-butoxyethanol; isobutyl acetate, butyl acetate, isopentyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropio , 2-methoxy-methylethyl acetate, 2-ethoxymethyl acetate, 2-ethoxyethyl acetate, methyl 3-methoxypropionate, diethyl carbonate, methyl isovalerate, methyl lactate, ethyl lactate, 3-methyl Ester solvents such as xylbutyl acetate and 3-methyl-3-methoxybutyl acetate; 2-methyl-4-pentanone, acetylacetone, cyclohexanone, cyclopentanone, 4-hydroxyn-4-methyl-2-pentanone, 3, Ketone solvents such as 5,5-trimethyl-2-cyclohexen-1-one, 2,6-dimethyl-4-heptanone, methyl butyl ketone, methyl isobutyl ketone; ethylene glycol monomethyl ether, propylene glycol monomethyl ether, anisole, Ethers such as ethylene glycol monoethyl ether, ethylene glycol mono tert-butyl ether, ethylene glycol monobutyl ether, 3-methyl-3-methoxybutanol, diethylene glycol monobutyl ether Solvents; organic acid solvents such as formic acid and acetic acid; amide solvents such as formamide, N, N-dimethylformamide and dimethylacetamide; amine solvents such as morpholine and N-ethylmorpholine; toluene, xylene, styrene and mineral spirits And aromatic hydrocarbon solvents such as turpentine oil; and chlorinated hydrocarbon solvents such as 1,1,2,2-tetrachloroethylene, 1,2-dichlorobenzene and trichloroethylene.
Among these, 1-methoxy-2-propanol, 1-butanol, cyclohexanol, cyclohexanone, cyclopentanone, morpholine, N-ethylmorpholine, anisole, and isobutyl acetate are preferable from the viewpoint of ease of handling.

Among these, it is preferable that the solvent A has water solubility from the viewpoint that the environmental load can be reduced by using water as the liquid B.
Here, the water solubility of the solvent A means that 1 g of the solvent A is added to 99 g of water, and the solvent A dissolves in water when stirred at room temperature for 100 minutes, that is, by visual separation or dispersion. It means a uniform liquid phase without turbidity.

Here, the solvent A may be composed of one of the above-mentioned solvents, or may be a combination of two selected from these solvents.
Here, the content of the solvent A in the coating solution used in this step is not limited as long as the necessary film thickness is secured after coating, and the viscosity that is easy to apply according to the coating method and the dissolution of the solvent It may be determined by sex or the like. Specifically, the content of the solvent A is preferably 60% by mass to 97% by mass, more preferably 80% by mass to 97% by mass, and still more preferably 90% by mass to 95% by mass with respect to the coating solution.

Moreover, the coating liquid used at this process may contain various additives as needed. Specifically, materials such as rubber and SBR latex, binders for improving film properties, plasticizers, surfactants, viscosity modifiers and the like that can relieve the stress of the obtained polymer layer can be mentioned. .
That is, as the surfactant, an anionic surfactant such as sodium n-dodecylbenzenesulfonate, a cationic surfactant such as n-dodecyltrimethylammonium chloride, polyoxyethylene nonylphenol ether, polyoxyethylene sorbitan monolaurate Nonionic surfactants such as polyoxyethylene lauryl ether are used.
Plasticizers include phthalates (dimethyl ester, diethyl ester, dibutyl ester, di-2-ethylhexyl ester, dinormal octyl ester, diisononyl ester, dinonyl ester, diisodecyl ester, dibutyl benzyl ester), adipic acid esters (Dioctyl ester, diisononyl ester), azelain san dioctyl, sebacin sun ester (dibutyl ester, dioctyl ester), tricresyl phosphate, tributyl acetylcitrate, epoxidized soybean oil, trioctyl trimellitic acid, chlorinated paraffin, dimethylacetamide, High boiling solvents such as N-methylpyrrolidone can also be used.
Furthermore, you may add additives, such as a coloring agent, a flame retardant, an adhesive imparting agent, a silane coupling agent, antioxidant, a ultraviolet absorber, as needed.

The coating solution containing each component as described above is applied onto a support by a known coating method such as spin coating, spray coating, dip coating, or bar coating.
The coating amount (film thickness) may be appropriately determined according to the use of the polymer layer to be formed. In general, the film thickness is preferably 0.1 μm to 20 μm, and preferably 0.5 μm to 7 μm. It is more preferable.

[Support]
The support used in this step is not particularly limited as long as it has shape retention, and may be appropriately determined according to the application. Therefore, the shape of the support is not particularly limited.
In addition, the support may be made of a material having adhesiveness with the polymer layer. In addition, when the polymer layer after drying is peeled off from the support, the adhesiveness with the polymer layer may be used. A material with no material may be used.
Specific examples of the support include paper, paper laminated with plastic (eg, polyethylene, polypropylene, polystyrene, etc.), metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose diacetate, Cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate, cellulose nitrate, polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polyvinyl acetal, polyimide, epoxy, polycarbonate, ABS resin (acrylonitrile-butadiene-styrene copolymer), bismalein Imide resin, polyphenylene oxide, liquid crystal polymer, polytetrafluoroethylene, etc.), paper or plastic film on which a metal as described above is laminated or vapor-deposited, etc. Used.

As described above, in this step, an uncured coating film is formed on the support.

[(B) Process]
In the step (b) in the present invention, the coating film formed in the step (a) is brought into contact with the liquid B containing at least one of water and alcohol that does not dissolve the specific polymer, and the solvent A is removed from the coating film. remove.
In addition, from the viewpoint that the removal amount of the solvent A in the finally formed polymer layer is increased, the step (a) and the step (b) are preferably performed continuously, and in particular, (a) It is preferable not to include a drying step between the step and the step (b).

[Liquid B]
First, the liquid B used in this step will be described.
The liquid B is a liquid having a boiling point lower than that of the solvent A, and includes at least one of water and alcohol and does not dissolve the specific polymer. In the present invention, the boiling point in the case where the liquid B is a mixed liquid of two or more solvents means that the liquid B, which is the mixed liquid, is heated under normal pressure, and the temperature of the liquid becomes constant. The temperature at which the temperature of the liquid does not rise any further even when the heating is continued and the liquid B evaporates is indicated.
Here, the fact that the specific polymer is not dissolved means that a solution in which 1% of the specific polymer is added to the liquid B is stirred at 300 ° C. for 300 minutes to form a uniform liquid phase after standing. This means that a precipitate is confirmed.

In this step, at least one of water and alcohol satisfying the above-described solubility is used as the liquid B. In addition, when mixing and using alcohol and water, the mixing ratio is preferably 60% or less of alcohol, more preferably 40% or less of alcohol, and 5% is preferable as the lower limit of alcohol.
Here, as the alcohol, all alcohols can be used, and among them, alcohols having 4 or less carbon atoms are preferable from the viewpoint of boiling point and drying temperature. Specifically, methanol, ethanol, 1- Propanol, 2-propanol, butanol, 2-methyl-1-propanol, 2-methyl-2-propanol and 2-butanol are preferably used. In addition to the above, alcohol derivatives such as 3-amino-1-propanol, trifluoroethyl methacrylate, pentadecafluorooctanol and the like may be used. In the present specification, the term “alcohol” includes alcohol and its derivatives.

Moreover, the boiling point of the liquid B used at this process is lower than the boiling point of the solvent A used at the (a) process. By satisfying such a relationship, the drying temperature after replacing the solvent A with the liquid B can be lowered and the drying can be performed in a short time.
In particular, the difference between the boiling point of the liquid B and the boiling point of the solvent A is preferably 10 ° C. or higher, and more preferably 20 ° C. or higher. From the viewpoint of easy handling of the liquid B and the solvent A, the upper limit of the difference between the boiling points of the two is preferably 350 ° C., more preferably 180 ° C. or less, and further preferably 100 ° C. or less. preferable.

The content of one or more selected from water and alcohol in the liquid B is preferably 50% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, from the viewpoint of addition to equipment and environmental load. Preferably, 100 mass% is still more preferable. That is, the liquid B is preferably made of water or alcohol or a mixture of water and alcohol. When the liquid B contains alcohol, the alcohol may include a plurality of types selected from alcohol and alcohol derivatives.

In this step, the solvent A is removed from the coating film by bringing the liquid B described above into contact with the coating film formed in the step (a).
Here, as a method of bringing the liquid B into contact with the coating film, there are a method of immersing a support having a coating film in the liquid B, and a method of washing the coating film using the liquid B.

The residual amount of the solvent A in the coating film after this step is preferably 20% by mass or less, more preferably 15% by mass or less, and further preferably 10% by mass or less.
The residual amount of the solvent A can be measured as follows.
That is, both are dissolved using a certain amount of liquid that dissolves both the coating film and solvent A, and the amount of solvent A in the solution is measured using liquid chromatography.

When the solvent A is removed from the coating film as described above, the liquid B enters the area instead of the solvent A.
Here, the liquid B is composed of water and / or alcohol, and since the liquid B has a lower boiling point than the solvent A, the removability from the coating film is superior to the solvent A. Therefore, the coating film can be dried in a short time by performing the step (c) described later after this step.
In addition, since water and alcohol are used in this step, the workability is excellent, which is advantageous in terms of equipment cost, and the solvent A can be recovered in the liquid B without evaporating. The load can be reduced.

[(C) Step]
In the step (c) in the present invention, the coating film after the step (b) is dried.
The conditions for drying performed in this step may be appropriately determined depending on the heat resistance of the support for forming the coating film and the boiling point of the liquid B.
In particular, if the boiling point of the liquid B used in step (b) is 80 ° C. or less, drying at room temperature is possible. For example, since a small amount of ethanol is dried immediately at room temperature, it can be dried at room temperature as long as the boiling point of ethanol is around 78 ° C.

In this step, heat drying may be performed. The conditions at that time may be appropriately determined depending on the heat resistance of the support for forming the coating film and the boiling point of the liquid B.
Specifically, the heating temperature is preferably 180 ° C. or less, more preferably 10 ° C. to 120 ° C., and further preferably 60 ° C. to 100 ° C.
The heating time is preferably 120 minutes or less, more preferably 60 minutes or less, and even more preferably 1 second to 10 minutes.
Various heaters, warm air, infrared rays, and the like can be used for the above-described heat drying.

In the present invention, as described above, after replacing the solvent A in the coating film with the liquid B, drying is performed, so that the drying temperature is lowered and the drying time is shortened, but the film remains in the coating film. The amount of solvent can be reduced. Therefore, a polymer layer free from voids can be formed. Since the polymer layer having no voids is uniform in the inside of the layer, it is possible to suppress a local decrease in film strength even under high temperature and high humidity.
In particular, as described above, since the liquid B has better removability from the coating film than the solvent A, drying can be performed at room temperature, or the temperature during heat drying can be lowered. Therefore, in the present invention, it is possible to use a polymer and / or a support having low heat resistance.

The porosity in the polymer layer formed as described above is preferably 50% or less, more preferably 20% or less, and most preferably 1% or less.
That is, in the method for forming a polymer layer of the present invention, a void-free polymer layer is formed through the above-described steps, so that the void ratio as described above can be achieved in the polymer layer.
Here, the porosity of the polymer layer can be measured by cross-sectional SEM observation of the polymer layer. Specifically, the method described in the examples is used.

<Application of polymer layer>
The polymer layer obtained in the present invention can itself be applied as a layer to be plated, as described in JP-A-2007-107022. In addition, a polymer layer newly formed on the polymer layer can be applied as a layer to be plated. In this application, the following polymers are appropriately used as the specific polymer P described above.
Hereinafter, a polymer layer (hereinafter, appropriately referred to as “lower layer”) obtained by the present invention or a polymer layer newly formed on the polymer layer (hereinafter, appropriately referred to as “upper layer”). The aspect which is a to-be-plated layer is demonstrated. The layer to be plated is preferably made of a polymer having a functional group that interacts with a plating catalyst or a precursor thereof, and an embodiment using such a polymer will be described in detail below. In addition, when a to-be-plated layer is a polymer layer (upper layer) newly formed on the polymer layer obtained by this invention, this polymer layer (upper layer) is a polymer layer containing a cyano group in a layer. Is preferred.

Here, as a functional group that interacts with the plating catalyst or its precursor (hereinafter simply referred to as “interactive group”), a polar group (hydrophilic group) or a group that can form a multidentate coordination. , Non-dissociable functional groups (functional groups that do not generate protons by dissociation) such as nitrogen-containing functional groups, sulfur-containing functional groups, and oxygen-containing functional groups. In particular, in order to reduce the water absorption and hygroscopicity of the plated layer, it is preferable to use a non-dissociable functional group as the interactive group.

The polar group may be a functional group having a positive charge, such as ammonium or phosphonium, or a negative charge such as a sulfonic acid group, a carboxyl group, a phosphoric acid group, or a phosphonic acid group, or can be dissociated into a negative charge. An acidic group is mentioned. These adsorb metal ions in the form of counterions of dissociating groups.
Further, for example, nonionic polar groups such as a hydroxyl group, an amide group, a sulfonamide group, an alkoxy group, and a cyano group can also be used.
In addition, an imino group, primary or secondary amino group, amide group, urethane group, hydroxyl group (including phenol), thiol group, and the like can also be used.

As the non-dissociable functional group, specifically, a group capable of forming a coordination with a metal ion, a nitrogen-containing functional group, a sulfur-containing functional group, an oxygen-containing functional group, and the like are preferable. Group, pyridine group, tertiary amino group, ammonium group, pyrrolidone group, amidino group, triazine ring, triazole ring, benzotriazole group, benzimidazole group, quinoline group, pyrimidine group, pyrazine group, nazoline group, quinoxaline group, purine Group, triazine group, piperidine group, piperazine group, pyrrolidine group, pyrazole group, aniline group, group containing alkylamine group structure, group containing isocyanuric structure, nitro group, nitroso group, azo group, diazo group, azide group, cyano Group, nitrogen-containing functional group such as cyanate group (R—O—CN), hydroxyl group, carbonate group, ether group, carbonyl , Ester groups, groups containing an N-oxide structure, groups containing an S-oxide structure, oxygen-containing functional groups such as a group containing an N-hydroxy structure, thiophene group, thiol group, thiocyanuric acid group, benzthiazole group, mercaptotriazine Groups, thioether groups, thiooxy groups, sulfoxide groups, sulfone groups, sulfite groups, groups containing sulfoximine structures, groups containing sulfoxynium salt structures, sulfur-containing functional groups such as groups containing sulfonate structures, Examples thereof include phosphorus-containing functional groups such as phosphoroamide groups and phosphine groups, groups containing halogen atoms such as chlorine and bromine, and unsaturated ethylene groups. In addition, an imidazole group, a urea group, or a thiourea group may be used as long as it is non-dissociative due to a relationship with an adjacent atom or atomic group. Furthermore, for example, it may be a functional group derived from a compound having an inclusion ability such as cyclodextrin and crown ether.
Among them, it is represented by an ether group (more specifically, —O— (CH ₂ ) _n —O— (n is an integer of 1 to 5) because of its high polarity and high adsorption ability to a plating catalyst or the like. A cyano group is particularly preferable, and a cyano group is most preferable.

Generally, the higher the polarity, the higher the water absorption rate. However, since the cyano groups interact in the polymer layer so as to cancel each other's polarity, the film becomes dense and the entire polymer layer Therefore, the water absorption is lowered. Further, by adsorbing the catalyst with the good solvent of the polymer layer, the cyano group is solvated, the interaction between the cyano groups is eliminated, and it becomes possible to interact with the plating catalyst. In view of the above, a polymer layer having a cyano group is preferable in that it exhibits low performance while interacting well with the plating catalyst while exhibiting low moisture absorption.
Further, the interactive group in the present invention is more preferably a cyanoalkyl group. This is because the cyano aromatic group attracts electrons to the aromatic ring and lowers the donation of unpaired electrons, which is important for adsorptivity to the plating catalyst, etc., but the cyanoalkyl group is bonded to this aromatic ring. Therefore, it is preferable in terms of adsorptivity to the plating catalyst.

Moreover, as a polymer which has the above interactive groups, in order to raise the film | membrane intensity | strength of a to-be-plated layer, you may have a polymeric group further.
In particular, when the layer to be plated is a polymer layer (upper layer) newly formed on the polymer layer obtained in the present invention, this polymer layer (upper layer) has adhesion to the lower polymer layer. In order to obtain excellent adhesion between the film and the plating film, it is preferably formed using a polymer having an interactive group and a polymerizable group.

-Aspect where the polymer layer obtained in the present invention contains a cyano group-
Hereinafter, the aspect in which the polymer layer obtained in the present invention contains a cyano group will be described. This embodiment can be obtained by forming a polymer layer using a polymer having a cyano group.
By using a polymer having a cyano group, excellent adhesion to such a support or plating film can be obtained even when there are few irregularities at the interface between the support and the plating film formed thereon. .
Although this effect is not clear, it is estimated as follows.
A polymer having a cyano group is formed into a film, thereby forming a polymer layer as a lower layer having excellent adhesion to the support because it has excellent wettability and affinity for the resin substrate as the support. be able to. In addition, by applying a coating solution containing a polymer having an interactive group and a polymerizable group to the surface of the lower polymer layer and drying it to form the upper polymer layer, the compatibility between the polymers is achieved. Due to the affinity, it is possible to form a plated layer having an interactive group that has excellent adhesion to the support. In particular, since the polymer having an interactive group and a polymerizable group has a polymerizable group (preferably a radical polymerizable group) in the molecule, it has a crosslinked structure by being cured by applying energy. A simple polymer layer can be formed. The upper polymer layer formed in this manner is excellent in adhesion to the support and can form an interaction with the plating catalyst or its precursor. Even if the interface is in a hybrid state between the metal and the polymer (resin) and the interface between the support and the plating film is smooth, it is considered that the adhesion between them is high.

The polymer having a cyano group suitable for the lower layer is not particularly limited as long as it is a polymer having a unit having a cyano group in the side chain as a polymerization component, but as the unit having a cyano group in the side chain, acrylonitrile is preferable. The polymer having a cyano group is preferably a polymer containing such a unit.
Specifically, acrylonitrile-butadiene-styrene copolymer (ABS) resin, nitrile-butadiene rubber (NBR), acrylonitrile-styrene copolymer (AS) resin, polyacrylonitrile, and the like are particularly preferable.
In addition, the polymer having a cyano group preferably includes a unit derived from a monomer having a cyano group as shown below as a polymerization component.

 

 

 
 

In the above monomers, R represents a hydrogen atom or a methyl group.

The polymer having a cyano group may contain only one type of unit derived from the above monomer or two or more types, and may contain a unit not containing a cyano group as a copolymerization component. The amount of the cyano group contained in the polymer having a cyano group is preferably 1.0 mmol to 9.0 mmol per 1 g of the polymer from the viewpoint of adhesion between the support and the upper polymer layer.
The other unit contained in the polymer having a cyano group is not particularly limited as long as it is a unit not containing a polar group. For example, a unit having a linear or cyclic olefin structure, a conjugated diene unit, a polarity A polymerizable monovinyl aromatic unit having no group, a unit derived from a (meth) acrylate monomer having no polar group, a unit derived from a (meth) acrylamide monomer having no polar group, and the like are preferable. Specifically, for example, units derived from monomers as shown below can be mentioned.

 

In the above monomers, R represents a hydrogen atom or a methyl group, and X represents O or NH.

In the polymer having a cyano group, the content when the unit having a cyano group in the side chain is contained as a polymerization component is preferably in the range of 10 mol% to 100 mol%, more preferably 30 mol%. Mol% to 100 mol%.
The weight average molecular weight of the polymer having a cyano group is preferably 1000 or more and 700,000 or less, more preferably 2000 or more and 200,000 or less.
In particular, from the viewpoint of adhesion to the support, the polymer having a cyano group preferably has a weight average molecular weight of 10,000 or more. Moreover, as a polymerization degree of the polymer which has a cyano group, it is preferable to use a 10-mer or more thing, More preferably, it is a 20-mer or more thing. Moreover, 7000-mer or less is preferable, 3000-mer or less is more preferable, 2000-mer or less is still more preferable, 1000-mer or less is especially preferable.

Hereinafter, specific examples of the cyano group-containing polymer used in the present invention will be shown, but the present invention is not limited thereto.

 
 

 

 
 

The polymer having a cyano group described above is preferably used in the polymer layer obtained in the present invention.
In addition, if the polymer having a cyano group described above further has a structure having a polymerizable group (a structure including a unit having a polymerizable group), the polymer newly formed on the polymer layer obtained in the present invention. It becomes a polymer suitable for the layer (upper layer).

The polymer layer obtained by the method for forming a polymer layer of the present invention can be applied to, for example, personal computer parts, automobile parts, home appliance parts, decorative parts, and the like. In the method for forming a polymer layer of the present invention, ABS resin (acrylonitrile-butadiene-styrene copolymer), polycarbonate, liquid crystal polymer, polyimide, epoxy, acrylic, TAC, nitrile butadiene rubber, etc. are used depending on the intended use. It is possible to form a polymer layer.
In particular, as described above, a polymer layer (lower layer) is formed using a polymer having an interactive group as a specific polymer, or a polymer having an interactive group is used on the polymer layer obtained in the present invention. Thus, if the polymer layer (upper layer) is formed, the formed lower layer and upper layer can be plated layers. Thus, if a to-be-plated layer is formed, a plating film can be formed on this to-be-plated layer by using for the following processes.

[Plating catalyst application process]
First, a plating catalyst or a precursor thereof is applied to the layer to be plated.
In this step, the interactive group possessed by the polymer constituting the layer to be plated adheres (adsorbs) the applied plating catalyst or its precursor depending on its function.
Here, examples of the plating catalyst or its precursor include those that function as a plating catalyst or an electrode in a plating step described later. Therefore, a plating catalyst or its precursor is determined by the kind of plating in a plating process.
Here, the plating catalyst or its precursor used in this step is preferably an electroless plating catalyst or its precursor.

(Electroless plating catalyst)
As the electroless plating catalyst used in the present invention, any catalyst can be used as long as it becomes an active nucleus at the time of electroless plating. Specifically, a metal (Ni And the like, which are known as metals capable of electroless plating with a lower ionization tendency), and specifically, Pd, Ag, Cu, Ni, Al, Fe, Co, and the like. Among them, those capable of multidentate coordination are preferable, and Ag and Pd are particularly preferable in view of the number of types of functional groups capable of coordination and high catalytic ability.
This electroless plating catalyst may be used as a metal colloid. In general, a metal colloid can be prepared by reducing metal ions in a solution containing a charged surfactant or a charged protective agent. The charge of the metal colloid can be adjusted by the surfactant or protective agent used here.

(Electroless plating catalyst precursor)
The electroless plating catalyst precursor used in this step can be used without particular limitation as long as it can become an electroless plating catalyst by a chemical reaction. The metal ions of the metals mentioned as the electroless plating catalyst are mainly used. The metal ion that is an electroless plating catalyst precursor becomes a zero-valent metal that is an electroless plating catalyst by a reduction reaction. The metal ion, which is an electroless plating catalyst precursor, may be used as an electroless plating catalyst after being applied to the layer to be plated and before being immersed in the electroless plating bath, by separately changing to a zero-valent metal by a reduction reaction. The electroless plating catalyst precursor may be immersed in an electroless plating bath and changed to a metal (electroless plating catalyst) by a reducing agent in the electroless plating bath.

Actually, the metal ion which is the electroless plating precursor is applied onto the layer to be plated using a metal salt. The metal salt used is not particularly limited as long as it is dissolved in an appropriate solvent and dissociated into a metal ion and a base (anion), and M (NO ₃ ) _n , MCn, M _{2 / n} (SO ₄ ), M _{3 / n} (PO ₄ ) (M represents an n-valent metal atom), and the like. As a metal ion, the thing which said metal salt dissociated can be used suitably. Specific examples include, for example, Ag ions, Cu ions, Al ions, Ni ions, Co ions, Fe ions, and Pd ions. Among them, those capable of multidentate coordination are preferable, and in particular, functionalities capable of coordination. In view of the number of types of groups and catalytic ability, Ag ions and Pd ions are preferable.

As a preferred example of the electroless plating catalyst or precursor thereof used in the present invention, a palladium compound may be mentioned. This palladium compound acts as a plating catalyst (palladium) or a precursor thereof (palladium ions), which acts as an active nucleus during the plating treatment and plays a role of depositing metal. The palladium compound is not particularly limited as long as it contains palladium and acts as a nucleus in the plating process, and examples thereof include a palladium (II) salt, a palladium (0) complex, and a palladium colloid.

Examples of the palladium salt include palladium acetate, palladium chloride, palladium nitrate, palladium bromide, palladium carbonate, palladium sulfate, bis (benzonitrile) dichloropalladium (II), bis (acetonitrile) dichloropalladium (II), and bis (ethylenediamine). ) Palladium (II) chloride and the like. Of these, palladium nitrate, palladium acetate, palladium sulfate, and bis (acetonitrile) dichloropalladium (II) are preferable in terms of ease of handling and solubility.
Examples of the palladium complex include tetrakistriphenylphosphine palladium complex and dipalladium trisbenzylideneacetone complex.
The palladium colloid is a particle composed of palladium (0), and its size is not particularly limited, but is preferably 5 nm to 300 nm, more preferably 10 nm to 100 nm, from the viewpoint of stability in the liquid. The palladium colloid may contain other metals as necessary, and examples of the other metals include tin. Examples of the palladium colloid include tin-palladium colloid. In addition, a palladium colloid may be synthesize | combined by a well-known method and a commercial item may be used. For example, a palladium colloid can be prepared by reducing palladium ions in a solution containing a charged surfactant or a charged protective agent.

Moreover, as an electroless-plating catalyst used by this invention, or its precursor, silver and a silver ion are mentioned as another preferable example from a viewpoint that it can selectively adsorb | suck to a to-be-plated layer.
When silver ions are used as the plating catalyst precursor, those obtained by dissociating silver compounds as shown below can be suitably used. Specific examples of the silver compound include silver nitrate, silver acetate, silver sulfate, silver carbonate, silver cyanide, silver thiocyanate, silver chloride, silver bromide, silver chromate, silver chloranilate, silver salicylate, silver diethyldithiocarbamate, Examples thereof include silver diethyldithiocarbamate and silver p-toluenesulfonate. Among these, silver nitrate is preferable from the viewpoint of water solubility.

As a method of applying a metal that is an electroless plating catalyst or a metal salt that is an electroless plating precursor to a layer to be plated, a dispersion in which the metal is dispersed in an appropriate dispersion medium, or a metal salt that is an appropriate solvent. Prepare a solution containing dissolved and dissociated metal ions and apply the dispersion or solution on the layer to be plated, or immerse the support on which the layer to be plated is formed in the dispersion or solution. do it.

Further, instead of the method as described above, a method of adding an electroless plating catalyst or a precursor thereof to a coating solution for forming a plated layer may be used. That is, a composition containing a polymer for forming a layer to be plated and an electroless plating catalyst or a precursor thereof is applied onto a support and dried, and then a coating containing a plating catalyst or a precursor thereof is coated. A plating layer may be formed. If this method is used, the process can be omitted.

When a resin film is used as the support and the plated layers are formed on both sides of the resin film, the electroless plating catalyst or its precursor is simultaneously contacted with the plated layers on both sides. Therefore, it is preferable to use the above immersion method.

By contacting the electroless plating catalyst or its precursor as described above, the interaction group in the layer to be plated can interact with an intermolecular force such as van der Waals force, or be distributed by a lone electron pair. An electroless plating catalyst or a precursor thereof can be adsorbed by utilizing the interaction due to the coordinate bond.
From the viewpoint of sufficiently performing such adsorption, the metal concentration in the dispersion, solution, or composition, or the metal ion concentration in the solution may be in the range of 0.001% by mass to 50% by mass. The range of 0.005% by mass to 30% by mass is more preferable.
The contact time is preferably about 30 seconds to 24 hours, more preferably about 1 minute to 1 hour.

When a palladium compound is used in the solution, dispersion, or composition containing the electroless plating catalyst or its precursor, the palladium compound is 0.001 mass relative to the total amount of the solution, dispersion, or composition. % To 10% by mass, more preferably 0.05% to 5% by mass, and further preferably 0.10% to 1% by mass.
When a silver compound is used in the solution containing the electroless plating catalyst precursor, the silver compound is preferably used in a range of 0.1% by mass to 20% by mass with respect to the total amount of the solution. More preferably, it is used in the range of 20% by mass to 20% by mass, and more preferably in the range of 0.5% by mass to 10% by mass.
Regardless of which compound is used, if the content is too small, it will be difficult to deposit the plating described later. If the content is too large, the plating may be deposited to an undesired region, or the etching residue removal property will be reduced. It may be damaged.

Regarding the adsorption amount of the plating catalyst of the layer to be plated or its precursor, depending on the type of electroless plating catalyst or its precursor to be used, for example, in the case of silver ions, from the viewpoint of the depositability of electroless plating 300 mg / m ² or more is preferable, 500 mg / m ² or more is more preferable, and 600 mg / m ² or more is more preferable. Further, from the viewpoint of producing a plating film having high adhesion to the support, the adsorption amount of silver ions of the layer to be plated is preferably 1000 mg / m ² or less.
In the case of palladium ions, the adsorption amount of the layer to be plated is preferably 5 mg / m ² or more, more preferably 10 mg / m ² or more, from the viewpoint of the depositability of electroless plating. Further, from the viewpoint of producing a plating film having high adhesion to the support, the amount of palladium ion adsorbed on the layer to be plated is preferably 1000 mg / m ² or less.

(Other catalysts)
In the present invention, a zero-valent metal can be used as a catalyst used for direct electroplating on the layer to be plated without performing electroless plating in the plating step described later. Examples of the zero-valent metal include Pd, Ag, Cu, Ni, Al, Fe, and Co. Among them, those capable of multidentate coordination are preferable, and in particular, adsorption to an interactive group (cyano group) ( Pd, Ag, and Cu are preferable from the viewpoint of adhesion and high catalytic ability.

(Organic solvent and water)
As described above, the plating catalyst or precursor as described above is applied to the layer to be plated as a dispersion or solution (catalyst solution).
An organic solvent or water is used for the catalyst solution in the present invention.
By containing this organic solvent, the permeability of the plating catalyst or precursor to the layer to be plated is improved, and the plating catalyst or precursor thereof can be efficiently adsorbed to the interactive group.

Water may be used for the catalyst solution in the present invention, and it is preferable that this water does not contain impurities. From such a viewpoint, RO water (reverse osmosis membrane filtered water), deionized water, distillation Water, purified water or the like is preferably used, and deionized water or distilled water is particularly preferably used.

The organic solvent used for the preparation of the plating catalyst solution is not particularly limited as long as it is a solvent that can penetrate into the layer to be plated. Specifically, acetone, methyl acetoacetate, ethyl acetoacetate, ethylene glycol diacetate, Cyclohexanone, acetylacetone, acetophenone, 2- (1-cyclohexenyl), propylene glycol diacetate, triacetin, diethylene glycol diacetate, dioxane, N-methylpyrrolidone, dimethyl carbonate, dimethyl cellosolve, and the like can be used.

Other organic solvents include diacetone alcohol, γ-butyrolactone, methanol, ethanol, isopropyl alcohol, normal propyl alcohol, propylene glycol monomethyl ether, methyl cellosolve, ethyl cellosolve, ethylene glycol tertiary butyl ether, tetrahydrofuran, 1,4 dioxane. N-methyl-2-pyrrolidone and the like.

In particular, a water-soluble organic solvent is preferable from the viewpoint of compatibility with a plating catalyst or a precursor thereof and permeability to a layer to be plated. Acetone, dimethyl carbonate, dimethyl cellosolve, triethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol Diethyl ether is preferred.

Furthermore, the catalyst solution in the present invention may contain other additives depending on the purpose.
Other additives include, for example, swelling agents (organic compounds such as ketones, aldehydes, ethers, esters, etc.) and surfactants (anionic, cationic, zwitterionic, nonionic and low molecular or high molecular weight). Etc.).

By passing through the plating catalyst provision process demonstrated above, interaction can be formed between the interactive group in a to-be-plated layer, and a plating catalyst or its precursor.

[Plating process]
As described above, a plating film is formed by performing plating on the layer to be plated to which the plating catalyst or its precursor has been applied. The formed plating film has excellent conductivity and adhesion.
The type of plating performed in this step includes electroless plating, electroplating, etc., and in the plating catalyst application step, depending on the function of the plating catalyst or its precursor that forms an interaction with the layer to be plated, You can choose.
That is, in this step, electroplating may be performed on the layer to be plated to which the plating catalyst or its precursor has been applied, or electroless plating may be performed.
Among these, in the present invention, it is preferable to perform electroless plating from the viewpoint of improving the formability and adhesion of the hybrid structure that appears in the layer to be plated. Further, in order to obtain a plating film having a desired film thickness, it is a more preferable aspect that electroplating is further performed after electroless plating.
Hereinafter, the plating suitably performed in this step will be described.

(Electroless plating)
Electroless plating refers to an operation of depositing a metal by a chemical reaction using a solution in which metal ions to be deposited as a plating are dissolved.
In the electroless plating in this step, for example, a support having a layer to be plated to which an electroless plating catalyst is applied is washed with water to remove excess electroless plating catalyst (metal), and then immersed in an electroless plating bath. And do it. As the electroless plating bath to be used, a generally known electroless plating bath can be used.
In addition, when a support having a layer to be plated with an electroless plating catalyst precursor is immersed in an electroless plating bath in a state where the electroless plating catalyst precursor is adsorbed or impregnated in the layer to be plated, a substrate is used. Is washed with water to remove excess precursor (metal salt, etc.) and then immersed in an electroless plating bath. In this case, reduction of the plating catalyst precursor and subsequent electroless plating are performed in the electroless plating bath. As the electroless plating bath used here, a generally known electroless plating bath can be used as described above.
In addition, the reduction of the electroless plating catalyst precursor may be performed as a separate step before electroless plating by preparing a catalyst activation liquid (reducing liquid) separately from the embodiment using the electroless plating liquid as described above. Is possible. The catalyst activation liquid is a liquid in which a reducing agent capable of reducing electroless plating catalyst precursor (mainly metal ions) to zero-valent metal is dissolved, and the concentration of the reducing agent with respect to the whole liquid is 0.1 mass% to 50 mass. %, Preferably 1% by mass to 30% by mass. As the reducing agent, it is possible to use a boron-based reducing agent such as sodium borohydride or dimethylamine borane, or a reducing agent such as formaldehyde or hypophosphorous acid.
When dipping, maintain the concentration of the electroless plating catalyst or its precursor in the vicinity of the surface of the layer to be plated with which the electroless plating catalyst or its precursor comes into contact, and soak with stirring or shaking. Is preferred.

General composition of electroless plating bath is as follows: 1. metal ions for plating; 2. reducing agent; Additives (stabilizers) that improve the stability of metal ions are mainly included. In addition to these, the plating bath may contain known additives such as a plating bath stabilizer.

The organic solvent used in the plating bath needs to be a water-soluble solvent, and from this point, ketones such as acetone and alcohols such as methanol, ethanol, and isopropanol are preferably used.

As the types of metals used in the electroless plating bath, copper, tin, lead, nickel, gold, palladium, and rhodium are known, and copper and gold are particularly preferable from the viewpoint of conductivity.

Moreover, the optimal reducing agent and additive are selected according to the said metal.
For example, a copper electroless plating bath contains CuSO ₄ as a copper salt, HCOH as a reducing agent, a chelating agent such as EDTA or Rochelle salt, which is a stabilizer of copper ions, and a trialkanolamine. .
The plating bath used for electroless plating of CoNiP includes cobalt sulfate and nickel sulfate as metal salts, sodium hypophosphite as a reducing agent, sodium malonate, sodium malate, and sodium succinate as complexing agents. It is included. Moreover, the electroless plating bath of palladium contains (Pd (NH ₃ ) ₄ ) Cl ₂ as metal ions, NH ₃ and H ₂ NNH ₂ as reducing agents, and EDTA as a stabilizer. These plating baths may contain components other than the above components.

The thickness of the plating film formed by electroless plating can be controlled by the metal ion concentration of the plating bath, the immersion time in the plating bath, or the temperature of the plating bath. From the viewpoint, it is preferably 0.1 μm or more, and more preferably 0.2 μm to 2 μm.
However, when electroplating described later is performed using a plating film formed by electroless plating as a conductive layer, it is sufficient that a film of at least 0.1 μm or more is provided uniformly.
The immersion time in the plating bath is preferably about 1 minute to 6 hours, and more preferably about 1 minute to 3 hours.

The plating film obtained by electroless plating obtained as described above has fine particles of a plating catalyst and a plating metal dispersed at a high density in the layer to be plated by cross-sectional observation with a scanning electron microscope (SEM). Further, it is confirmed that the plating metal is deposited on the layer to be plated. Since the interface between the layer to be plated and the plating film is a hybrid state of the resin composite and fine particles, the interface between the layer to be plated (organic component) and the inorganic substance (plating catalyst metal or plating metal) is smooth (for example, 1 mm Adhesiveness is good even if Ra is 1.5 μm or less in the region ² .

(Electroplating)
In this step, when the plating catalyst or its precursor applied in the plating catalyst application step has a function as an electrode, electroplating is performed on the layer to be plated to which the catalyst or its precursor is applied. be able to.
In addition, after the above-described electroless plating, the formed plating film may be used as an electrode, and electroplating may be further performed. As a result, a new metal film having an arbitrary thickness can be easily formed on the electroless plating film having excellent adhesion to the substrate. Thus, since electroplating is performed after electroless plating, the plating film can be formed to a thickness according to the purpose, and thus the obtained plating film is suitable for application to various applications.

A conventionally known method can be used as the electroplating method in the present invention. In addition, as a metal used for the electroplating of this process, copper, chromium, lead, nickel, gold, silver, tin, zinc, etc. are mentioned. From the viewpoint of conductivity, copper, gold, and silver are preferable, and copper is preferable. More preferred.

Moreover, the film thickness of the plating film obtained by electroplating can be controlled by adjusting the metal concentration contained in the plating bath, the current density, or the like.
Note that the thickness of the metal film when the obtained plated film is applied to general electric wirings is preferably 0.5 μm or more, more preferably 1 μm to 30 μm from the viewpoint of conductivity.
In addition, the thickness of the electrical wiring is reduced in order to maintain the aspect ratio as the line width of the electrical wiring is reduced, that is, as the size is reduced. Therefore, the thickness of the plating film formed by electroplating is not limited to the above, and can be set arbitrarily.
Japanese Patent Application No. 2009-217794, filed on Sep. 18, 2009, the entire disclosure of which is incorporated herein by reference.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto. Unless otherwise specified, “%” and “part” are based on mass.

[Examples 1 to 3]
A solution (9% by mass solution) of acrylonitrile-styrene copolymer (AS) resin (Aldrich Co., Ltd., glass transition temperature: 100 ° C.) dissolved in cyclohexanone (boiling point: 156 ° C.) was prepared. It applied to the glass epoxy resin board | substrate using the coater (it applied so that the film thickness might be 6 micrometers after drying).
Then, the board | substrate which has the obtained coating film is water (boiling point: 100 degreeC, Example 1), methanol (boiling point: 64.7 degreeC, Example 2), or a water / methanol (1/1) liquid mixture ( It was immersed for 10 seconds in Example 3). The boiling point of the mixture measured by heating the water / methanol (1/1) mixture as described above was 71 ° C.
When the residual amount of cyclohexanone in the coating film after immersion was measured, it was 7.5% by mass (Example 1), 6.0% by mass (Example 2), and 8.8% by mass (Example 3). It was.

Then, it dried for 5 minutes at 60 degreeC using oven.
FIG. 1 shows the residual amount of cyclohexanone in the polymer layer obtained after drying.
Further, the obtained polymer layer was subjected to cross section processing by FIB using a FEI Nova-200 type FIB-SEM, and then a cross section SEM observation showed no voids.

[Comparative Examples 1 to 4]
A liquid (9% by mass solution) obtained by dissolving the AS resin used in Example 1 in cyclohexanone was prepared and applied to a glass epoxy resin substrate using a spin coater (so that the film thickness after drying was 6 μm). Applied to).
Thereafter, it was heated and dried at 60 ° C. for 8 hours, and then dried at room temperature for 0 days (Comparative Example 1), 1 day (Comparative Example 2), 3 days (Comparative Example 3), or 7 days (Comparative Example 4). .

The residual amount of cyclohexanone in the polymer layer obtained after drying is shown in FIG. For comparison of the examples, the residual amount of cyclohexanone in the polymer layer obtained after drying of Example 2 is shown in FIG.
As is clear from FIG. 2, by contacting the coating film with methanol as in Example 2, the remaining amount of cyclohexanone in the coating film is greatly reduced as compared with the case of vacuum drying for a long period of time as in the comparative example. You can see that
Further, when the obtained polymer layer was subjected to cross-sectional processing by FIB using a FEI Nova-200 type FIB-SEM, cross-sectional SEM observation revealed that voids were formed.

[Examples 4 to 6]
A liquid (3% by mass solution) obtained by dissolving the AS resin used in Example 1 in N-ethylmorpholine (boiling point: 138 ° C.) was prepared, and this was applied to a glass epoxy resin substrate using a spin coater ( (Apply so that the film thickness is 1 μm after drying).
Thereafter, the substrate having the obtained coating film was subjected to water (boiling point: 100 ° C., Example 4), ethanol (boiling point: 78.4 ° C., Example 5), isopropanol (boiling point: 82.4 ° C., Example 6). ) For 10 seconds.
When the residual amount of N-ethylmorpholine in the coating film after immersion was measured, it was 0.95% by mass (Example 4), 0.56% by mass (Example 5), 0.93% by mass (Example 6). )Met.

Then, it dried at 60 degreeC for 5 minute (s) using the oven similarly to Example 1. FIG.
FIG. 3 shows the residual amount of N-ethylmorpholine in the polymer layer obtained after drying.
Further, after drying, the polymer layer obtained was subjected to cross section processing by FIB using Nova-200 type FIB-SEM manufactured by FEI, and then observed by cross section SEM, no void was observed in any of the samples.

[Comparative Example 5]
A liquid (3% by mass solution) obtained by dissolving the AS resin used in Example 1 in N-ethylmorpholine (boiling point: 138 ° C.) was prepared, and this was applied to a glass epoxy resin substrate using a spin coater ( (Apply so that the film thickness is 1 μm after drying).
Thereafter, the substrate having the coating film was dried by heating at 60 ° C. for 8 hours, and the residual amount of N-ethylmorpholine in the polymer layer after drying was measured. The result is shown in FIG.

As is clear from FIG. 3, by contacting the solvent A as in Examples 4 to 6, the residual amount of N-ethylmorpholine in the coating film was higher than that in the case of drying for a long time as in Comparative Example 5. It can be seen that there is a significant decrease.

[Examples 7 to 9]
Instead of the AS resin used in Example 1, a liquid (3 mass% solution) prepared by dissolving polymethyl methacrylate resin (Aldrich Co., Ltd., glass transition temperature: 99 ° C.) (PMMA resin) in cyclohexanone was prepared. This was applied to a glass epoxy resin substrate using a spin coater (applied so that the film thickness after drying was 3 μm). Thereafter, the substrate having the obtained coating film was subjected to water (boiling point: 100 ° C., Example 7), ethanol (boiling point: 78.4 ° C., Example 8), isopropanol (boiling point: 82.4 ° C., Example 9). ) For 10 seconds.
When the residual amount of cyclohexanone in the coating film after immersion was measured, it was 3.83% by mass (Example 7), 3.32% by mass (Example 8), and 2.04% by mass (Example 9). It was.

Then, it dried at 60 degreeC for 5 minute (s) using the oven similarly to Example 1. FIG.
FIG. 4 shows the residual amount of cyclohexanone in the polymer layer obtained after drying.
Further, after drying, the polymer layer obtained was subjected to cross section processing by FIB using Nova-200 type FIB-SEM manufactured by FEI, and then observed by cross section SEM, no void was observed in any of the samples.

[Comparative Example 6]
A liquid (3 mass% solution) obtained by dissolving the PMMA resin used in Examples 7 to 9 in cyclohexanone was prepared, and this was applied to a glass epoxy resin substrate using a spin coater (the film thickness after drying was 3 μm). To be applied).
Then, the board | substrate which has a coating film was heat-dried at 60 degreeC for 8 hours, and the residual amount of cyclohexanone in the polymer layer after drying was measured. The result is shown in FIG.

As is clear from FIG. 4, by contacting the solvent A as in Examples 7 to 9, the residual amount of cyclohexanone in the coating film was greatly reduced as compared with the case of drying for a long time as in Comparative Example 6. You can see that

[Examples 10 and 11, Reference Example 1]
A liquid (9% by mass solution) obtained by dissolving AS resin in cyclohexanone was prepared, and this was applied to a glass epoxy resin substrate using a spin coater (applied so that the film thickness after drying was 6 μm).
Thereafter, the substrate having the obtained coating film was subjected to heat drying at 60 ° C. for 4 hours (Reference Example 1). After the drying, water (boiling point: 100 ° C., Example 10) or methanol (boiling point: 64.7). C. for 10 seconds in Example 11).
Here, when the residual amount of cyclohexanone in the coating film after drying at 60 ° C. for 4 hours was measured, it was 13.2% by mass (Reference Example 1).
Moreover, it was 11.9 mass% (Example 10) and 11.1 mass% (Example 11) when the residual amount of the cyclohexanone in the coating film after contact was measured.

Then, it dried at 60 degreeC for 5 minute (s) using the oven similarly to Example 1. FIG.
FIG. 5 shows the remaining amount of cyclohexanone in the polymer layer obtained after drying. For comparison, the residual amount of cyclohexanone in the coating film after heating and drying at 60 ° C. for 4 hours (Reference Example 1), the residual amount of cyclohexanone in the polymer layers obtained in Examples 1 and 2, and Is shown in FIG.
Further, after drying, the polymer layer obtained was subjected to cross section processing by FIB using Nova-200 type FIB-SEM manufactured by FEI, and then observed by cross section SEM, no void was observed in any of the samples.

As is clear from FIG. 5, when the coating film was heated and dried at 60 ° C. for 4 hours and then contacted with water or ethanol (Examples 11 and 12), the coating film was not dried by heating. In the case of contact with water or ethanol (Examples 1 and 2), it can be seen that the residual amount of cyclohexanone in the obtained polymer layer is very small.
Thereby, in order to reduce the residual amount of the solvent A in the finally obtained polymer layer, it is preferable that a drying step is not included between the steps (a) and (b) in the present invention. I understand.

[Examples 12 and 13, Comparative Example 7]
A liquid (9% by mass solution) obtained by dissolving AS resin in cyclohexanone was prepared, and this was applied to a glass epoxy resin substrate using a spin coater (applied so that the film thickness after drying was 6 μm).
Thereafter, the substrate having the obtained coating film was subjected to heat drying at 60 ° C. for 1 h (Comparative Example 7) to form a polymer layer.
In addition, the substrate having the obtained coating film was immersed in water (boiling point: 100 ° C., Example 12) for 5 minutes, or immersed in methanol (boiling point: 64.7 ° C., Example 13) for 3 minutes. The polymer layer was formed by drying at 60 ° C. for 5 minutes.

The obtained polymer layer was held at 60 ° C. and 95% for 100 hours, and then fixed to a jig using an adhesive, and a tensile strength tester (manufactured by Shimadzu Corporation, Autograph) was used to obtain a tensile strength of 10 mm / min. The 90 ° peel strength was measured at 0.24 kN / m (Comparative Example 7), 0.52 kN / m (Example 12), and 0.45 kN / m (Example 13), respectively. It was. In addition, when the peeling part was observed, it was all internal destruction of AS resin. The results are shown in FIG.
From this result, it can be seen that a void-free polymer layer can be formed by the method for forming a polymer layer of the present invention, and as a result, the film strength of the polymer layer is increased.

[Examples 14 and 15, Comparative Example 8]
A liquid (9% by mass solution) obtained by dissolving AS resin in cyclohexanone was prepared, and this was applied to a glass epoxy resin substrate using a spin coater (applied so that the film thickness after drying was 6 μm).
Thereafter, the substrate having the obtained coating film was subjected to heat drying at 60 ° C. for 1 h (Comparative Example 8) to form a polymer layer.
In addition, the substrate having the obtained coating film was immersed in water (boiling point: 100 ° C., Example 14) for 5 minutes, or immersed in methanol (boiling point: 64.7 ° C., Example 15) for 3 minutes. The polymer layer was formed by drying at 60 ° C. for 5 minutes.

The porosity of the obtained polymer layer was measured by the following method and found to be 58% (Comparative Example 8), 0% (Example 14), and 0% (Example 15), respectively.
The obtained polymer layers of Examples 14 and 15 and Comparative Example 8 were subjected to FIB Nova-200 type FIB-SEM and subjected to FIB cross section processing at one random location (acceleration voltage 30 kV). ), Cross-sectional SEM observation was performed (acceleration voltage 2 kV).
The porosity is calculated by calculating the area of voids (voids) in the cross-sectional SEM photograph and the total area of the polymer layer containing the voids using a cross-sectional SEM photograph having a size of about 10 μm × 10 μm. As in (1), the void area was divided by the total area of the polymer layer and multiplied by 100. Since the cross section of each void is very close to a circle, treat it as a circle or an ellipse, find the area from its diameter (longer and shorter diameter in the case of an ellipse), and add them together. The area of voids in the cross-sectional SEM photograph was determined.
Formula (1) Porosity (%) = void area / total area of polymer layer × 100
From this result, it can be seen that the polymer layer forming method of the present invention can form a polymer layer having no voids and a low porosity.

As described above, in each of the above embodiments, most of the cyclohexanone and N-ethylmorpholine (solvent A) in the coating film were obtained by bringing water and / or alcohol into contact with the coating film for a short time of 10 seconds. Was found to be removed. Moreover, since the removal effect of the solvent A became high, it turned out that it is preferable to perform the contact of the liquid B to a coating film before drying a coating film. Moreover, it turned out that the void (void | void) in a polymer layer is hard to be formed by removing most of the solvent A in a coating film.
As described above, according to the method of the present invention, the solvent in the polymer layer can be removed in a shorter time by selecting the polymer coating solvent and the liquid in which the polymer is immersed, and the polymer without voids. It can be seen that the layer can be formed in a short drying time. And it turned out that film | membrane intensity | strength becomes high by forming a polymer layer without a void.

ADVANTAGE OF THE INVENTION According to this invention, the formation method of a polymer layer which can form a polymer layer without a void in short drying time irrespective of the boiling point of the solvent used for a coating liquid can be provided.
According to the method for forming a polymer layer of the present invention, a polymer layer having excellent in-plane uniformity of film strength can be obtained.
In addition, regarding the solvent used for the coating solution that normally diffuses into the atmosphere in the drying step, the present invention can recover the solvent A corresponding to this solvent in the liquid B, thereby reducing the environmental burden. it can.

The above description of specific embodiments of the present invention is provided for purposes of description and explanation. It is not intended to limit the invention to the precise form disclosed, nor is it intended to be exhaustive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments have been selected to best illustrate the concepts of the invention and their practical application, and thus various embodiments and methods to adapt them to specific applications contemplated by others skilled in the art. It is intended to allow others skilled in the art to understand the present invention so that various modifications can be made.

All publications, patent applications, and technical standards mentioned in this specification are intended to be specifically and individually incorporated by reference as individual references, patent applications, and technical standards. Is incorporated herein to the same extent as the cited references. It is intended that the scope of the invention be determined by the following claims and their equivalents.

Claims (8)

1. (A) applying a coating liquid containing a polymer P having a glass transition temperature of 180 ° C. or less and a solvent A for dissolving the polymer P on a support to form a coating film;
   (B) contacting the coating film with a liquid B containing at least one of water and alcohol that does not dissolve the polymer P, and removing the solvent A from the coating film;
   (C) drying the coating film;
   In this order,
   A method for forming a polymer layer in which the solvent A and the liquid B satisfy the following relationship.
   Boiling point of solvent A> Boiling point of liquid B
2. The method for forming a polymer layer according to claim 1, wherein the porosity in the polymer layer is 50% or less.
3. The method for forming a polymer layer according to claim 1, wherein the boiling point of the solvent A and the glass transition temperature of the polymer P satisfy the following relationship.
   Boiling point of solvent A> Glass transition temperature of polymer P-50 ° C
4. The method for forming a polymer layer according to any one of claims 1 to 3, wherein the alcohol is an alcohol having 4 or less carbon atoms.
5. The method for forming a polymer layer according to any one of claims 1 to 3, wherein the solvent A is water-soluble.
6. The method for forming a polymer layer according to any one of claims 1 to 3, wherein the polymer P is a polymer containing a cyano group.
7. The method for forming a polymer layer according to claim 5, wherein the polymer P is a polymer containing a cyano group.
8. The method for forming a polymer layer according to claim 6, wherein the polymer containing a cyano group is a polymer containing a cyanoalkyl group in a side chain.
   

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