CN104220541B - Permanent seal cooling waterproof moisture resistance coating composition - Google Patents

Abstract

The present invention provides a durable waterproof-moisture-proof coating composition comprising (I) a fluorine-containing polymer and (II) a fluorine-based solvent, wherein the (I) fluorine-containing polymer will contain a fluoroalkyl group A polymer obtained by free radical polymerization of acrylate esters containing fluoroalkyl groups. The acrylate esters containing fluoroalkyl groups have fluoroalkyl groups that are ester-bonded to carboxyl groups directly or through divalent organic groups, and may have substituents at the α position , the (I) fluorine-containing polymer comprises the polymer shown in the following (1) or (2): (1) by making the acrylate containing the fluoroalkyl group and the free alkoxysilyl group The polymer obtained by radically polymerizing the monomer components of the radically polymerizable monomer, (2) by subjecting the fluoroalkyl-containing acrylate to radical polymerization in the presence of an alkoxysilyl-containing mercaptan Polymers obtained by polymerization. According to the present invention, it is possible to obtain a coating composition capable of forming a coating film with excellent durability and good waterproof and moisture-proof performance on various substrates, especially electronic parts.

Description

Durable waterproof-moisture-proof coating composition

technical field

The present invention relates to a coating composition capable of forming a water-repellent and moisture-proof coating film excellent in wear resistance on various substrates, and a coating composition that can be applied to electronic parts requiring chemical resistance without inhibiting their functions. In some cases, it is a coating composition that forms a waterproof and moisture-proof coating film with excellent abrasion resistance.

Background technique

In recent years, with the spread of multifunctional mobile terminals represented by smartphones and tablet PCs, methods for imparting waterproof and moisture-proof properties have become a subject. These devices are difficult to package with conventional silicone rubber because a large number of electronic components are arranged in a small frame and there are almost no extra spaces. In addition, non-fluorine-based waterproof and moisture-proof coating agents represented by HumiSeal (manufactured by Chase Corp., U.S.) cannot exhibit sufficient waterproof-moisture-proof performance unless they are formed into a very thick film thickness of 100 μm or more.

The fluorine-based waterproof-moisture-proof coating agent in the form of dissolving fluoroalkyl (meth)acrylate homopolymer in a fluorine-based solvent can exhibit sufficient waterproof-moisture-proof performance with a film thickness of 1 μm or less, so it is mobile in a multifunctional The usage in the terminal is high profile. However, the existing fluorine-based waterproof-moisture-proof coating agent has insufficient abrasion resistance, and there is a problem that the operator on the production line or the assembly device touches the waterproof-moisture-proof processed part by mistake, or the consumer reuses the waterproof-moisture-proof processed part. Connectors and earphone jacks cause the fluoropolymer to peel off, making it impossible to maintain the initial waterproof and moisture-proof performance.

In addition, it is known to apply a solution obtained by dissolving a polyfluoroalkyl group-containing polymer in a nonflammable low-boiling point solvent on the surface of an electronic component, and dry the solvent to form a polyfluoroalkyl group-containing polymer. The method of coating film (refer to the following patent document 1). However, the treatment liquid used in this method cannot be used at present because the specified Freon, which is banned from use, is used as a solvent.

The following Patent Document 2 discloses a copolymer composed of a (meth)acrylate monomer containing a perfluoroalkyl group having 6 carbon atoms and a functional group-containing monomer, and a fluorine-based solvent capable of dissolving the copolymer. Fluorine-based surface modification composition. As the functional group of the copolymer, if a group that can chemically react with the substrate or has a good affinity is selected, it is expected that the abrasion resistance of the coating film will be improved. However, in the above-mentioned method, only about a few weight % of the functional group-containing monomer in the perfluoroalkyl (meth)acrylate-containing monomer is copolymerized, and there is a problem that the solubility to the fluorine-based solvent is low. Therefore, a sufficient amount of functional groups cannot be introduced, and the abrasion resistance of the coating film cannot be sufficiently improved.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 61-189693

Patent Document 2: Japanese Patent Laid-Open No. 2009-57530

Contents of the invention

The problem to be solved by the invention

The present invention was made in view of the above-mentioned state of the art, and its main purpose is to provide a coating combination capable of forming a coating film with excellent abrasion resistance and excellent waterproof and moisture-proof performance on various substrates. To provide a coating composition capable of forming a waterproof and moisture-proof coating excellent in abrasion resistance without inhibiting the function of electronic parts requiring chemical corrosion resistance.

means to solve the problem

The inventors of the present invention conducted intensive studies in order to achieve the above objects. As a result, it was found that using an acrylate having a fluoroalkyl group and optionally having a substituent at the α-position as a monomer has a negative effect on radically polymerizable monomers containing the fluoroalkyl-containing acrylate and an alkoxysilyl group-containing A polymer obtained by free-radical polymerization of monomer components, or a polymer obtained by free-radical polymerization of the fluoroalkyl-containing acrylate in the presence of an alkoxysilyl-containing mercaptan, for fluorine The solubility of hydrofluoroether as a solvent, especially a hydrofluoroether with low chemical aggressiveness and less adverse effect on the environment is good. Furthermore, it was found that a composition obtained by dissolving the fluorine-containing polymer in a fluorine-based solvent can form a waterproof-moisture-proof coating excellent in abrasion resistance without adversely affecting various materials including electronic parts, and completed the this invention.

That is, the present invention provides the following durable waterproof-moisture-proof coating composition and a method for forming a durable waterproof-moisture-proof film.

Item 1.

A durable waterproof-moistureproof coating composition, characterized in that it comprises (I) a fluorine-containing polymer and (II) a fluorine-based solvent,

Wherein, the (I) fluorine-containing polymer is a polymer obtained by free-radical polymerization of fluoroalkyl-containing acrylate, and the fluoroalkyl-containing acrylate has a divalent organic group and a carboxyl group directly or via a divalent A fluoroalkyl group that is ester-bonded and may have a substituent at the α-position,

Described (I) fluorine-containing polymer comprises the polymer shown in following (1) or (2):

(1) A polymer obtained by radically polymerizing a monomer component comprising the fluoroalkyl group-containing acrylate and the alkoxysilyl group-containing radically polymerizable monomer,

(2) A polymer obtained by radically polymerizing the fluoroalkyl group-containing acrylate in the presence of an alkoxysilyl group-containing thiol.

Item 2. The durable waterproof-moisture-proof coating composition according to the above Item 1, wherein the fluoroalkyl-containing acrylate is a compound represented by the following general formula (1):

(wherein, X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identical or different hydrogen atoms, fluorine atoms or chlorine atoms.), A cyano group, a straight-chain or branched fluoroalkyl group with 1 to 21 carbon atoms, a substituted or unsubstituted benzyl group, a substituted or unsubstituted phenyl group, or a straight-chain or branched fluoroalkyl group with 1 to 20 carbon atoms Branched chain alkyl, Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or a carbon that may have an oxygen atom A cycloaliphatic group having 6 to 10 atoms, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, a -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein R ¹ is carbon Alkyl group with 1 to 4 atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or acetyl group.), or -(CH ₂ ) _n SO ₂ ^- group (n 1 to 10), Rf is a linear or branched fluoroalkyl group having 1 to 20 carbon atoms.).

Item 3. The durable waterproof-moisture-proof coating composition according to the above item 2, wherein the fluoroalkyl-containing acrylate is a straight chain having 4 to 6 carbon atoms in the general formula (1). A carboxylic acid ester substituted at the α-position, wherein X is an atom or group other than a hydrogen-like or branched-chain fluoroalkyl group.

Item 4. The durable waterproof-moisture-proof coating composition according to any one of the above items 1 to 3, wherein the fluorine-containing polymer is obtained by making an acrylate containing a fluoroalkyl group and an alkoxymethyl group It is a polymer obtained by radically polymerizing monomer components of a silyl radical polymerizable monomer, and a copolymer obtained by also using a high softening point monomer as a monomer component.

Item 5. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 3, wherein the fluorine-containing polymer is obtained by making the fluoropolymer in the presence of an alkoxysilyl group-containing mercaptan This fluoroalkyl group-containing acrylate is a polymer obtained by radical polymerization, and is a copolymer obtained by also using a high softening point monomer as a monomer component.

Item 6. The durable waterproof-moisture-proof coating composition according to any one of the above items 1 to 3 and 5, wherein the fluorine-containing polymer is formed by the presence of an alkoxysilyl group-containing mercaptan The polymer obtained by radically polymerizing the fluoroalkyl group-containing acrylate is a copolymer obtained by further using an alkoxysilyl group-containing radically polymerizable monomer as a monomer component.

Item 7. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 4 and 6, wherein the radically polymerizable monomer containing an alkoxysilyl group is represented by the formula (2) Compounds shown,

(wherein, R ² , R ³ and R ⁴ are identically or differently alkyl groups with 1 to 4 carbon atoms or alkoxy groups with 1 to 4 carbon atoms, at least one of R ² , R ³ and R ⁴ is an alkoxy group, and R ⁵ is a group containing a radically polymerizable unsaturated bond.).

Item 8. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 3, 5 to 7, wherein the alkoxysilyl group-containing mercaptan is represented by the general formula (3) Compounds shown:

(In the formula, R ⁷ , R ⁸ and R ⁹ are the same or different alkyl groups with 1 to 4 carbon atoms or alkoxy groups with 1 to 4 carbon atoms, at least one of R ⁷ , R ⁸ and R ⁹ is an alkoxy group. R ¹⁰ is a linear alkylene group having 1 to 12 carbon atoms.).

Item 9. The durable waterproof-moisture-proof coating composition according to any one of 4 to 8 above, wherein the high softening point monomer is a glass transition of a homopolymer formed from the high softening point monomer A monomer having a temperature or melting point of 100°C or higher.

Item 10. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 4, 7 and 9, wherein the fluorine-containing polymer has a structure represented by the following general formula (5): Part of the polymer:

(wherein, X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identical or different hydrogen atoms, fluorine atoms or chlorine atoms.), A cyano group, a straight-chain or branched fluoroalkyl group with 1 to 21 carbon atoms, a substituted or unsubstituted benzyl group, a substituted or unsubstituted phenyl group, or a straight-chain or branched fluoroalkyl group with 1 to 20 carbon atoms A branched chain alkyl group. Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or an aromatic group that may have an oxygen atom A cycloaliphatic group having 6 to 10 carbon atoms, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, a -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or an acetyl group.), or -(CH ₂ ) _n SO ₂ ^- (n is 1 to 10). Rf is a linear or branched fluoroalkyl group with 1 to 20 carbon atoms. R ² , R ³ and R ⁴ are the same or different ones with 1 to 4 carbon atoms An alkyl group or an alkoxy group with 1 to 4 carbon atoms, at least one of R ² , R ³ and R ⁴ is an alkoxy group. R ^5' is 2 derived from a group containing a radically polymerizable unsaturated bond Valence group. R ¹¹ is H or CH ₃ , R ¹² is a group having a saturated alkyl group with 4 to 20 carbon atoms and a ratio of carbon atoms to hydrogen atoms of 0.58 or more. l, m and n are respectively It is an integer of 1 or more, and the total of l, m, and n is a numerical value with a weight average molecular weight of 3,000 to 500,000. In addition, the order of existence of each repeating unit enclosed in parentheses with l, m, and n is in any order in the formula .).

Item 11. The durable waterproof-moisture-proof coating composition according to any one of items 1 to 3, 5 to 9, wherein the fluorine-containing polymer is represented by the following general formula (6): Substances of polymers having an alkoxysilyl group at the end:

(wherein, X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identical or different hydrogen atoms, fluorine atoms or chlorine atoms.), A cyano group, a straight-chain or branched fluoroalkyl group with 1 to 21 carbon atoms, a substituted or unsubstituted benzyl group, a substituted or unsubstituted phenyl group, or a straight-chain or branched fluoroalkyl group with 1 to 20 carbon atoms A branched chain alkyl group. Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or an aromatic group that may have an oxygen atom A cycloaliphatic group having 6 to 10 carbon atoms, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, a -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or an acetyl group.), or -(CH ₂ ) _n SO ₂ ^- (n is 1 to 10). Rf is a linear or branched fluoroalkyl group with 1 to 20 carbon atoms. R ⁷ , R ⁸ and R ⁹ are the same or different ones with 1 to 4 carbon atoms An alkyl group or an alkoxy group with 1 to 4 carbon atoms, at least one of R ⁷ , R ⁸ and R ⁹ is an alkoxy group. R ¹⁰ is a linear alkylene group with 1 to 12 carbon atoms. n to make the weight-average molecular weight 3,000 to 500,000.).

Item 12. The durable waterproof-moisture-proof coating composition according to any one of Items 1 to 11, wherein the fluorine-based solvent is a hydrofluoroether.

Item 13. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 12, further comprising a compound having a perfluoropolyether skeleton.

Item 14. The durable waterproof-moisture-proof coating composition according to any one of the above Items 1 to 13, wherein the content of the compound having a perfluoropolyether skeleton is 1 part per 100 parts by weight of the fluoropolymer. ~20 parts by weight.

Item 15. The durable waterproof-moisture-proof coating composition for connectors of electronic components according to any one of Items 1 to 14, wherein the solid content concentration is 0.2 to 2% by weight.

Item 16. The durable waterproof and moisture-proof coating composition according to any one of the above items 1 to 15, wherein the object to be treated is an electronic component.

Item 17. A method for forming a durable waterproof-moisture-proof coating, comprising the step of bringing an object to be treated into contact with the durable waterproof-moisture-proof coating composition according to any one of Items 1 to 16 above.

Item 18. The method for forming a durable waterproof-moisture-proof coating according to Item 17 above, wherein the object to be treated is an electronic component.

Item 19. A connector of an electronic component, wherein a waterproof-moisture-proof coating is formed from the durable waterproof-moisture-proof coating composition described in Item 15 above.

Item 20. A fluoropolymer having a structural moiety represented by the following general formula (5):

(wherein, X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identical or different hydrogen atoms, fluorine atoms or chlorine atoms.), A cyano group, a straight-chain or branched fluoroalkyl group with 1 to 21 carbon atoms, a substituted or unsubstituted benzyl group, a substituted or unsubstituted phenyl group, or a straight-chain or branched fluoroalkyl group with 1 to 20 carbon atoms A branched chain alkyl group. Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or an aromatic group that may have an oxygen atom A cycloaliphatic group having 6 to 10 carbon atoms, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, a -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or an acetyl group.), or -(CH ₂ ) _n SO ₂ ^- (n is 1 to 10). Rf is a linear or branched fluoroalkyl group with 1 to 20 carbon atoms. R ² , R ³ and R ⁴ are the same or different ones with 1 to 4 carbon atoms An alkyl group or an alkoxy group with 1 to 4 carbon atoms, at least one of R ² , R ³ and R ⁴ is an alkoxy group, and R ^5' is 2 derived from a group containing a radically polymerizable unsaturated bond. Valence group. R ¹¹ is H or CH ₃ , R ¹² is a group having a saturated alkyl group with 4 to 20 carbon atoms and a ratio of carbon atoms to hydrogen atoms of 0.58 or more. l, m and n are respectively is an integer of 1 or more, and the total of l, m, and n is a numerical value such that the weight average molecular weight is 3,000 to 500,000. In addition, the order of existence of each repeating unit enclosed in parentheses with l, m, and n in the formula is in any order.).

Item 21. A fluoropolymer represented by the general formula (6):

(In the formula, X is a fluorine atom or a chlorine atom. Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, or an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom. An aliphatic group, a cycloaliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is an alkyl group with 1 to 4 carbon atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or an acetyl group.), or -(CH ₂ ) _n SO ₂ ^-group (n is 1 to 10). Rf is a linear or branched fluoroalkyl group with 1 to 20 carbon atoms. R ⁷ , R ⁸ and R ⁹ are the same or different carbon An alkyl group with 1 to 4 atoms or an alkoxy group with 1 to 4 carbon atoms, at least one of R ⁷ , R ⁸ and R ⁹ is an alkoxy group. R ¹⁰ is a linear chain with 1 to 12 carbon atoms The alkylene group. n is a numerical value such that the weight average molecular weight is 3,000 to 500,000.).

Next, the coating composition of the present invention will be specifically described.

Fluoropolymer

The fluorine-containing polymer compounded in the coating composition of the present invention is a fluoroalkyl group having a carboxyl group ester-bonded directly or via a divalent organic group, and may have a substituent acrylate (hereinafter sometimes "Fluoroalkyl-containing acrylate") is a polymer obtained by using the alkoxysilyl-containing acrylate and alkoxysilyl-containing radicals as monomer components. A copolymer obtained by copolymerizing the monomer components of a polymerizable monomer, or a copolymer obtained by radically polymerizing the fluoroalkyl-containing acrylate in the presence of an alkoxysilyl-containing mercaptan things.

Next, each component for obtaining the fluoropolymer of the present invention will be described.

(i) Monomer components

(1) Acrylic esters containing fluoroalkyl groups

Among the monomer components used in the production of the fluorine-based polymer used in the composition of the present invention, the fluoroalkyl-containing acrylate is a fluoroalkyl group directly or via a divalent organic group and may have a substituent at the α-position A substance formed by ester bonding of acrylic acid.

As a preferred specific example of the above-mentioned fluoroalkyl-containing acrylate, the acrylate represented by the following general formula (1) can be illustrated:

(wherein, X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identical or different hydrogen atoms, fluorine atoms or chlorine atoms.), A cyano group, a straight-chain or branched fluoroalkyl group with 1 to 21 carbon atoms, a substituted or unsubstituted benzyl group, a substituted or unsubstituted phenyl group, or a straight-chain or branched fluoroalkyl group with 1 to 20 carbon atoms A branched chain alkyl group, Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or an aromatic group that may have an oxygen atom A cycloaliphatic group having 6 to 10 carbon atoms, an araliphatic group having 6 to 10 carbon atoms which may have an oxygen atom, a -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is an alkyl group having 1 to 4 carbon atoms.), -CH ₂ CH(OY ¹ )CH ₂ ^- group (wherein, Y ¹ is a hydrogen atom or an acetyl group.), or -(CH ₂ ) _n SO ₂ ^- (n is 1 to 10), and Rf is a linear or branched fluoroalkyl group having 1 to 20 carbon atoms.).

In the above general formula (1), the fluoroalkyl group represented by Rf is an alkyl group in which at least one hydrogen atom is substituted by a fluorine atom, and includes a perfluoroalkyl group in which all hydrogen atoms are substituted by fluorine atoms.

Among the acrylates represented by the above general formula (1), it is preferable that Rf is a linear chain having 4 to 6 carbon atoms from the viewpoint of good solubility in fluorine-based organic solvents, especially hydrofluoroethers, to be described later. A linear or branched fluoroalkyl group, particularly preferably a linear or branched perfluoroalkyl group having 4 to 6 carbon atoms. In addition, when Rf is a linear or branched fluoroalkyl group having 4 to 6 carbon atoms, in order to further improve the water resistance of the formed coating, in the above general formula (1), preferably The substituent at the α-position represented by X is a group other than a hydrogen atom or an α-position-substituted acrylate of an atom. In particular, when the substituent X at the α-position is a methyl group, a chlorine atom, or a fluorine atom, it is possible to form a film having good water resistance using an inexpensive raw material. In particular, when the substituent X at the α-position is a methyl group, it is preferable from the viewpoint of a small corrosion effect on electronic parts.

The specific example of the acrylate represented by the said General formula (1) is as follows.

Rf·SO ₂ (CH ₂ ) ₃ ·OCO·CH=CH ₂

CH ₂ =C(-F)-C(=O)-O-(CH ₂ ) ₂ -S-Rf

CH ₂ =C(-F)-C(=O)-O-(CH ₂ ) ₂ -S-(CH ₂ ) ₂ -Rf

CH ₂ =C(-F)-C(=O)-O-(CH ₂ ) ₂ -SO ₂ -Rf

CH ₂ =C(-F)-C(=O)-O-(CH ₂ ) ₂ -SO ₂ -(CH ₂ ) ₂ -Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₂ -S-Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₂ -S-(CH ₂ ) ₂ -Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₂ -S0 ₂ -Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₂ -SO ₂ -(CH ₂ ) ₂ -Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₃ -S-Rf

CH ₂ =C(-Cl)-C(=O)-O-(CH ₂ ) ₃ -SO ₂ -Rf

CH ₂ =C(-CH ₃ )-C(=O)-O-(CH ₂ ) _z -Rf

CH ₂ =C(H)-C(=O)-O-(CH ₂ ) ₂ -Rf

The aforementioned fluoroalkyl-containing acrylates may be used alone or in combination of two or more.

(2) Radical polymerizable monomers containing alkoxysilyl groups

The alkoxysilyl group-containing radically polymerizable monomer used in the present invention is represented by the following composition formula (2).

In the above general formula (2), R ² , R ³ and R ⁴ are the same or different alkyl groups with 1 to 4 carbon atoms or alkoxy groups with 1 to 4 carbon atoms, and R ² , R ³ and R At least one of ⁴ is an alkoxy group. The alkoxy group is preferably methoxy, methoxy, etc., and it is particularly preferable that all of R ² , R ³ and R ⁴ are methoxy or ethoxy. R ⁵ is a group containing a radically polymerizable unsaturated bond.

By including the above-mentioned radically polymerizable monomer containing an alkoxysilyl group as a monomer component, a fluorine-containing polymer containing an alkoxysilyl group in the side chain can be formed, and the alkoxysilyl group contributes to To improve the adhesion to the substrate.

As this alkoxysilyl group containing radically polymerizable monomer, the monomer represented by following formula specifically, can be illustrated.

In each of the above formulas, R ² , R ³ and R ⁴ are the same as above, R ⁶ is a hydrogen atom, a methyl group or Cl, and n is an integer of 1-10.

The aforementioned alkoxysilyl group-containing radically polymerizable monomers may be used alone or in combination of two or more.

(ii) Mercaptans containing alkoxysilyl groups

Mercaptans containing alkoxysilyl groups are substances that function as chain transfer agents. While adjusting the degree of polymerization of polymers, a part of them is bonded to the formed fluorine-based polymers. The alkoxysilyl groups present at the ends The base helps to improve the adhesion to the base material, and can produce a fluoropolymer with excellent abrasion resistance.

As the alkoxysilyl group-containing thiol, any compound having an alkoxysilyl group containing at least one alkoxy group and a mercapto group can be used without particular limitation. As preferred alkoxysilyl-containing mercaptans, compounds represented by the following general formula (3) can be mentioned:

In the above general formula (3), R ⁷ , R ⁸ and R ⁹ are the same or different alkyl groups with 1 to 4 carbon atoms or alkoxy groups with 1 to 4 carbon atoms, and R ⁷ , R ⁸ and R At least one of ⁹ is an alkoxy group. The alkoxy group is preferably a methoxy group, and it is particularly preferable that all of R ⁷ , R ⁸ and R ⁹ are methoxy groups. R ¹⁰ is a linear alkylene group having 1 to 12 carbon atoms.

The aforementioned alkoxysilyl group-containing mercaptans may be used alone or in combination of two or more.

Among the alkoxysilyl group-containing mercaptans represented by the above general formula (3), it is preferable that R ¹⁰ is a straight chain having 1 to 4 carbon atoms from the viewpoint of solubility in fluorine-based solvents described later. like alkylene.

(iii) Manufacturing method of fluoropolymer

In the following, the method for producing the fluorine-containing polymer used in the present invention will be described as freeing monomer components including fluoroalkyl-containing acrylate and alkoxysilyl-containing radically polymerizable monomers. fluorine-containing polymer (hereinafter sometimes referred to as "fluorine-containing polymer 1") obtained by polymerizing radicals, and acrylates containing fluoroalkyl groups in the presence of mercaptans containing alkoxysilyl groups The polymerized fluoropolymer (hereinafter may be referred to as "fluoropolymer 2").

(1) Fluoropolymer 1

The fluorine-containing polymer 1 can be obtained by radically polymerizing monomer components including a fluoroalkyl group-containing acrylate and an alkoxysilyl group-containing radically polymerizable monomer as essential components.

It is preferable that the usage-amount of the radically polymerizable monomer containing an alkoxysilyl group is about 0.1-20 weight part with respect to 100 weight part of fluoroalkyl group containing acrylate used as a monomer component.

In the fluoropolymer 1, in addition to the fluoroalkyl group-containing acrylate and the alkoxysilyl group-containing radically polymerizable monomer, a monomer having a high softening point can be used as a monomer component if necessary. The high softening point monomer is a monomer whose glass transition temperature or melting point of a homopolymer composed of the high softening point monomer is 100°C or higher, preferably 120°C or higher. In this case, a polymer having a glass transition temperature needs to have a glass transition temperature of 100° C. or higher, and a polymer having no glass transition temperature needs to have a melting point of 100° C. or higher.

In addition, the glass transition temperature and the melting point were set to the extrapolated glass transition end temperature (T _eg ) and melting peak temperature (T _pm ) stipulated in JIS K7121-1987 "Methods for Measuring Transition Temperature of Plastics", respectively.

A high softening point monomer that satisfies the above-mentioned conditions is used as a monomer component together with the above-mentioned fluoroalkyl-containing acrylate and alkoxysilyl-containing radically polymerizable monomers. Films formed from fluoropolymers have excellent water-humidity resistance. Furthermore, the hardness of the coating film formed of the fluorine-containing polymer increases, and durability such as abrasion resistance becomes good.

In particular, a film formed of a fluoropolymer obtained by using a monomer having a high softening point as a monomer component has very good dynamic water repellency, which is an index showing the ability to remove water droplets adhering to the surface of the object to be treated. Therefore, even when water adheres to the surface of the object to be processed, such as a printed circuit board, the water removability is good, and the possibility of troubles caused by water can be greatly reduced. In addition, dynamic water repellency can be evaluated by the angle of decrease of water described in Examples described later.

The usage-amount of the said high softening point monomer is preferably about 1-30 weight part with respect to 100 weight part of fluoroalkyl-containing acrylates, More preferably, it is about 1-20 weight part.

As a high softening point monomer, (meth)acrylates represented by the following general formula (4) are particularly preferred:

CH ₂ =C(R ¹¹ )COOR ¹² (4)

(In the formula, R ¹¹ is H or CH ₃ , and R ¹² is a group having a saturated alkyl group having 4 to 20 carbon atoms and a ratio of carbon atoms to hydrogen atoms of 0.58 or more.). In general formula (4), specific examples of saturated alkyl groups having 4 to 20 carbon atoms and a ratio of carbon atoms to hydrogen atoms of 0.58 or more include: isobornyl group, bornyl group, fenzyl group ( All of the above are C ₁₀ H ₁₇ , carbon atom/hydrogen atom=0.58), adamantyl group (C ₁₀ H ₁₅ , carbon atom/hydrogen atom=0.66), norbornyl group (C ₇ H ₁₂ , carbon atom/hydrogen atom=0.66), 0.58) and other groups having cross-linked hydrocarbon rings. These crosslinked hydrocarbon rings may be directly bonded to the carboxyl group, or may be bonded to the carboxyl group via a linear or branched alkylene group having 1 to 5 carbon atoms. These crosslinked hydrocarbon rings may further be substituted with a hydroxyl group or an alkyl group (for example, the number of carbon atoms is 1 to 5).

Specific examples of high softening point monomers usable in the present invention include methyl methacrylate, phenyl methacrylate, and , cyclohexyl methacrylate, etc.

Examples of (meth)acrylates represented by the general formula (4) include (meth)acrylates having an isobornyl group, (meth)acrylates having a norbornyl group, and (meth)acrylates having an adamantyl group ( Meth)acrylate, etc. Among them, examples of (meth)acrylates having a norbornyl group include 3-methyl-norbornyl methyl (meth)acrylate, norbornyl methyl (meth)acrylate, (meth)acrylic acid Norbornyl ester, 1,3,3-trimethyl-norbornyl (meth)acrylate, myrtyl methyl (meth)acrylate, isopinepinyl (meth)acrylate, 2-{[ 5-(1',1',1'-trifluoro-2'-trifluoromethyl-2'-hydroxy)propyl]norbornyl}(meth)acrylate etc., as ( Examples of meth)acrylates include: 2-methyl-2-adamantyl (meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate, 3-hydroxy- 1-adamantyl ester, 1-adamantyl-α-trifluoromethyl (meth)acrylate, and the like.

In the present invention, other monomers may be used as necessary as monomer components for obtaining the fluoropolymer. Other monomers may be about 20% by weight or less, preferably 10% by weight or less, based on the total amount of monomer components used to obtain the fluoropolymer.

Other monomers can be selected from a wide range as long as they are copolymerizable with the fluoroalkyl group-containing acrylate, and as long as they do not adversely affect the performance of the obtained fluoropolymer. Examples include: aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, halogen-containing unsaturated compounds, silicon-containing unsaturated compounds, unsaturated dicarboxylic acid compounds, vinyl ester compounds, allyl ester compounds , unsaturated group-containing ether compounds, maleimide compounds, (meth)acrylates, acrolein, methacrolein, ring-polymerizable monomers, N-vinyl compounds, etc., but not limited on these.

The polymerization method is not particularly limited, but solution polymerization is preferably performed in a fluorine-based solvent. According to this method, since the fluorine-containing polymer formed has good solubility in a fluorine-based solvent, the radical polymerization reaction can proceed smoothly without forming a precipitate.

As the fluorine-based solvent, as long as it has a fluorine atom in the molecule and has good solubility of the formed fluorine-containing polymer, it may be any solvent among hydrocarbon compounds, alcohols, ethers, etc. In addition, aliphatic and aromatic solvents may be used. Any solvent in the family. For example, chlorinated fluorinated hydrocarbons (especially with 2 to 5 carbon atoms), especially HCFC225 (dichloropentafluoropropane), HCFC141b (dichlorofluoroethane), CFC316 (2,2,3,3 -tetrachlorohexafluorobutane), Vertrel XF (chemical formula C ₅ H ₂ F ₁₀ ) (manufactured by DuPont), hexafluoro-m-xylene, pentafluoropropanol, fluorine-based ethers, and the like.

In particular, when a hydrofluoroether is used as a solvent for the final coating composition, the same hydrofluoroether is also used as a solvent for the polymerization reaction, whereby the separation step of the fluoropolymer can be omitted to obtain efficiently Apply the composition.

Fluorinated solvents can be used alone or in combination of two or more.

In the case of radical polymerization of fluoroalkyl-containing acrylate in a fluorine-based solvent, for example, by dissolving the fluoroalkyl-containing acrylate in a solvent and adding a polymerization initiator while stirring the resulting solution, carry out the polymerization reaction.

As the polymerization initiator, any known polymerization initiator for radical polymerization can be used without particular limitation. For example, azo-based initiators such as azobisisobutyronitrile, methyl azoisobutyrate, and azobisdimethylvaleronitrile can be used; benzoyl peroxide, potassium persulfate, ammonium persulfate, dibenzyl Ketone derivatives, phosphine oxide derivatives, benzoketone derivatives, phenylsulfide derivatives, azide derivatives, diazo derivatives, disulfide derivatives, etc. These polymerization initiators may be used alone or in combination of two or more.

The amount of the polymerization initiator used is not particularly limited, but usually is preferably about 0.01 to 10 parts by weight, more preferably about 0.1 to 1 part by weight, based on 100 parts by weight of the fluoroalkyl group-containing acrylate used as a monomer component.

The concentration of the fluoroalkyl group-containing acrylate in the fluorine-based solvent is not particularly limited, but is generally preferably about 10 to 50% by weight, and more preferably about 20 to 40% by weight.

Polymerization conditions such as polymerization temperature and polymerization time can be appropriately adjusted according to the type of monomer component, its usage amount, the type of polymerization initiator, its usage amount, etc., but usually it only needs to be carried out at a temperature of about 50-100°C for 4~ 10 hours of polymerization is sufficient.

The weight average molecular weight of the fluorine-containing polymer 1 obtained by the above method is about 3,000 to 500,000, preferably about 5,000 to 300,000. The weight-average molecular weight of the fluoropolymer is a value obtained by GPC (gel permeation chromatography) using a mixed solvent of HCFC225/hexafluoroisopropanol (=90/10 by weight) as an eluting solvent (standard polymethacrylic acid Methyl ester conversion).

Fluoropolymer 1 obtained by the method described above is a copolymer having constituent units based on a fluoroalkyl group-containing acrylate and an alkoxysilyl group-containing radically polymerizable monomer. Moreover, when using a high softening point monomer, it becomes a copolymer containing the structural unit based on a high softening point monomer.

Among them, for example, a copolymer obtained by using (meth)acrylate represented by the above formula (4) as a high softening point monomer is a copolymer having a structural part represented by the following chemical formula (5). According to this copolymer, it is possible to form a coating film having excellent abrasion resistance, good water-moisture proof performance, and excellent water repellency and good water repellency.

In the above chemical formula (5), X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX ¹ X ² group (wherein, X ¹ and X ² are identically or differently hydrogen atoms, fluorine atoms or chlorine atom.), cyano group, linear or branched fluoroalkyl group with 1 to 21 carbon atoms, substituted or unsubstituted benzyl group, substituted or unsubstituted phenyl group, or fluoroalkyl group with 1 to 20 carbon atoms straight-chain or branched-chain alkyl. Y is a direct bond, an aliphatic group with 1 to 10 carbon atoms that may have an oxygen atom or a sulfur atom, an aromatic group with 6 to 10 carbon atoms that may have an oxygen atom, or an aromatic group with 6 carbon atoms that may have an oxygen atom Cycloaliphatic group with ∼10 carbon atoms, araliphatic group with 6 to 10 carbon atoms which may have an oxygen atom, -CH ₂ CH ₂ N(R ¹ )SO ₂ ^- group (wherein, R ¹ is a carbon atom with 1 ~4 alkyl group.), -CH ₂ CH(OY ¹ )CH ₂ ^-group (wherein, Y ¹ is a hydrogen atom or acetyl group.), or ^- (CH ₂ ) _n SO ₂ -group (n is 1～ 10). Rf is a linear or branched fluoroalkyl group having 1 to 20 carbon atoms. R ² , R ³ and R ⁴ are the same or different alkyl groups with 1 to 4 carbon atoms or alkoxy groups with 1 to 4 carbon atoms, and at least one of R ² , R ³ and R ⁴ is an alkoxy group . R ^5′ is a divalent group derived from the group R ⁵ in the compositional formula (2), that is, a divalent group derived from a radically polymerizable unsaturated bond-containing group. R ¹¹ is H or CH ₃ , and R ¹² is a group having a saturated alkyl group having 4 to 20 carbon atoms and a ratio of carbon atoms to hydrogen atoms of 0.58 or more. l, m, and n are each an integer of 1 or more, and the total of l, m, and n is a numerical value that makes the weight average molecular weight 3,000 to 500,000. In addition, the presence order of each repeating unit added with l, m, and n and enclosed in parentheses is an arbitrary order in the formula.

(2) Fluoropolymer 2

The fluoropolymer 2 can be obtained by radically polymerizing a fluoroalkyl group-containing acrylate in the presence of the aforementioned alkoxysilyl group-containing mercaptan.

The amount of the alkoxysilyl group-containing mercaptan used is preferably about 0.01 to 25 parts by weight, more preferably about 0.1 to 5 parts by weight, based on 100 parts by weight of the fluoroalkyl group-containing acrylate used as a monomer component.

In the fluorinated polymer 2, as in the fluorinated polymer 1, a high softening point monomer and other monomers can be used as monomer components as necessary. Specific examples of the high softening point monomer and other monomers are the same as those of the fluoropolymer 1, and the usage amounts are also the same as those of the fluoropolymer 1.

Furthermore, when producing the fluoropolymer 2, the alkoxysilyl group-containing radically polymerizable monomer used in the production of the fluoropolymer 1 can be used as a monomer if necessary. The kind and usage-amount of the radically polymerizable monomer containing an alkoxysilyl group should just be the same as fluoropolymer 1. The use of an alkoxysilyl group-containing radically polymerizable monomer further improves the adhesiveness to the base material of the fluoropolymer 2 .

The type and amount of the polymerization initiator used are the same as those of the fluoropolymer 1 .

About other polymerization conditions, what is necessary is just to be the same as fluorine-containing polymer 1.

The weight average molecular weight of the fluorine-containing polymer 2 obtained by the above method is about 3,000 to 500,000, preferably about 5,000 to 300,000. The weight-average molecular weight of the fluoropolymer is a value obtained by GPC (gel permeation chromatography) using a mixed solvent of HCFC225/hexafluoroisopropanol (=90/10 by weight) as an eluting solvent (standard polymethylformaldehyde base acrylate conversion).

The fluorine-containing polymer 2 obtained by the above-mentioned method becomes a substance containing the following polymer: the alkoxysilyl group-containing mercaptan of the general formula (3) and the monomer A polymer having an alkoxysilyl group at the terminal represented by the following general formula (6) in which polymer chains of a fluoroalkyl group-containing acrylate polymer of the general formula (1) are bonded.

In the above general formula (6), X, Y, Rf, R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are the same as above, n is a value corresponding to the above weight average molecular weight, that is, the general formula (6) The polymer has a weight-average molecular weight of 3,000 to 500,000.

Furthermore, in the case of using a high softening point monomer, the fluoropolymer 2 is a polymer containing a structural unit based on a high softening point monomer in addition to the structure represented by the above general formula (6). In the case of a radically polymerizable monomer containing an alkoxysilyl group, a constituent unit based on the radically polymerizable monomer containing an alkoxysilyl group is contained.

In addition, as described above, in the above general formula (6), the polymer in which X is a chlorine atom or a fluorine atom can be obtained using low-cost raw materials, and is a highly useful polymer that can form a coating with good water resistance. It is a new polymer that is unknown at present.

Durable waterproof-moisture-proof coating composition

The coating composition of the present invention is obtained by dissolving the fluoropolymer 1 or 2 obtained by the above-mentioned method in a fluorine-based solvent.

Fluoropolymer 1 and Fluoropolymer 2 obtained by the above method both have good water-repellent performance by containing a fluoroalkyl group, and the coating formed of the polymer exhibits good water-repellent performance.

Furthermore, the fluorine-containing polymer 1 obtained by using a radically polymerizable monomer containing an alkoxysilyl group as a monomer component has an alkoxysilyl group present through a side chain, and exhibits good resistance to various substrates. Combining and cross-linking substances, the formed coating has good abrasion resistance and waterproof-moisture-proof performance.

For the fluoropolymer 2 obtained by radical polymerization in the presence of an alkoxysilyl group-containing mercaptan, at least a part of the alkoxysilyl group-containing mercaptan present during the polymerization reaction and The polymer chains are bonded, and the alkoxysilyl groups present at the terminals also exhibit good binding properties to various substrates and have crosslinkability. As a result, the formed coating has excellent abrasion resistance and also has good water- and moisture-proof performance.

Furthermore, in the case of using a high softening point monomer as a monomer component, for either of the fluoropolymer 1 and the fluoropolymer 2, the water repellency of the formed coating is improved, and the water repellency is improved. good.

In the waterproof-moisture-proof coating composition of the present invention, by using a fluorine-based solvent, the above-mentioned fluorine-containing polymer can be stably dissolved, and a coating composition having good stability such as precipitation is less likely to occur can be obtained.

As the fluorine-based solvent, as long as it has a fluorine atom in the molecule and has good solubility of the formed fluorine-containing polymer, it can be any solvent among hydrocarbon compounds, alcohols, ethers, etc., and can also be aliphatic and aromatic solvents. Any solvent in the family. For example, chlorinated fluorinated hydrocarbons (especially with 2 to 5 carbon atoms), especially HCFC225 (dichloropentafluoropropane), HCFC141b (dichlorofluoroethane), CFC316 (2,2,3,3- Tetrachlorohexafluorobutane,), Vertrel XF (molecular formula C ₅ H ₂ F ₁₀ ) (manufactured by DuPont), hexafluoro-m-xylene, pentafluoropropanol, fluorine-based ether, and the like.

In the present invention, it is particularly preferable to use hydrofluoroether as the fluorine-based solvent. Hydrofluoroethers are solvents with low chemical aggressiveness to various materials, and are particularly suitable as solvents for coating compositions for electronic components that are strongly required to eliminate adverse effects of solvents. Moreover, hydrofluoroether is an ideal solvent having excellent properties such as quick-drying, low environmental pollution, non-flammability, and low toxicity.

In the present invention, the hydrofluoroether preferably has the formula: C _m F _2m+1 -OC _z H _2z+1 [wherein, m is a number from 1 to 6, and z is a number from 1 to 6. ] Compounds shown. As the above-mentioned hydrofluoroether, for example, Novec HFE7100 (chemical formula C ₄ F ₉ OCH ₃ ), 7200 (chemical formula C ₄ F ₉ OC ₂ H ₅ ), 7300 (chemical formula C ₂ F ₅ CF ( OCH ₃ ) C ₃ F ₇ ) etc.

In the present invention, in the general formula (1), Rf is a linear or branched fluoroalkyl group having 4 to 6 carbon atoms, and X is a group or atom other than a hydrogen atom. A coating composition comprising a fluoropolymer obtained by dissolving a fluoroalkyl-containing acrylate as a monomer component in hydrofluoroether. The fluorine-containing polymer formed by acrylate containing a fluoroalkyl group substituted by an α-position of a fluoroalkyl group with 4 to 6 carbon atoms in Rf has good solubility in hydrofluoroether, and the formed coating has excellent waterproof properties. A film with excellent wear resistance and moisture resistance, and good adhesion to the substrate.

In the coating composition of the present invention, the concentration of the fluorine-containing polymer in the composition is preferably about 0.01 to 30% by weight as a solid content concentration, more preferably about 0.1 to 20% by weight. In particular, when the object to be processed is a connector of an electronic component, by setting the solid content concentration to about 0.2 to 2% by weight, it is possible to form a material with good wear resistance and excellent wear resistance without inhibiting conductivity. Waterproof and moisture-proof coating.

The coating composition of the present invention can be used as a coating composition directly after performing radical polymerization in a fluorinated solvent by the above-mentioned method, after adjusting the concentration of the polymer, or can be used after radical polymerization. , isolate the fluorine-containing polymer, and then dissolve it in a fluorine-based solvent to obtain a coating composition. In the present invention, the target coating composition can be obtained efficiently by obtaining a coating composition after the polymerization reaction using hydrofluoroether as a solvent and then adjusting the polymer concentration using hydrofluoroether as necessary.

Furthermore, a compound having a perfluoropolyether (PFPE) skeleton (hereinafter sometimes referred to as "PFPE compound") may be blended in the coating composition of the present invention as needed. By blending the PFPE compound, the smoothness of the coating formed of the fluoropolymer is improved, and the abrasion resistance is greatly improved.

In the present invention, a compound represented by the following general formula (7) can be used as the PFPE compound.

A ¹ -B ¹ -R ^a -B ² -A ² (7)

In the above formula, A ¹ and A ² identically or differently represent a C _1-16 alkyl group that may be substituted by one or more fluorine atoms, or a group: -SiQ _k Y ^a _3-k (where : Y ^a represents a hydroxyl group, a hydrolyzable group or a hydrocarbon group, Q represents -Z ^a -SiR ^b _j R ^c _3-j (Z ^a is a divalent organic group, R ^b is a hydroxyl group or a hydrolyzable group, R ^c is a C _1-22 alkyl group or Q', Q' has the same meaning as Q, j is independently an integer from 0 to 3 in each of Q and Q', and the sum of j is 1 or more), and k represents 1 An integer of ~3.). B ¹ and B ² are the same or different and represent a single bond or a divalent organic group, and R ^a represents a perfluoropolyether group.

In the above formula (7), among the groups represented by A1 and _{A2, the "C1-16 alkyl group" in the C1-16} ^alkyl _group ^that may be substituted by one or more fluorine atoms A linear or branched alkyl group having 1 to 16 carbon atoms, preferably a linear or branched alkyl group having 1 to 3 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms .

The C _1-16 alkyl group substituted with one or more fluorine atoms is preferably a CF ₂ HC _1-15 perfluoroalkylene group, more preferably a C _1-16 perfluoroalkyl group.

The C _1-16 perfluoroalkyl group is a linear or branched perfluoroalkyl group with 1 to 16 carbon atoms, preferably a linear or branched perfluoroalkyl group with 1 to 3 carbon atoms, more preferably A linear perfluoroalkyl group having 1 to 3 carbon atoms, specifically -CF ₃ , -CF ₂ CF ₃ , or -CF ₂ CF ₂ CF ₃ .

In the above formula (7), R ^a is a perfluoropolyether group, specifically, for example, -(OC ₄ F ₈ ) _a -(OC ₃ F ₆ ) _b -(OC ₂ F ₄ ) _c -(OCF ₂ ) _d- . Here, a, b, c, and d are each independently an integer of 0 or 1 or more, and the sum of a, b, c, and d is not particularly limited as long as it is at least 1, and is preferably 0 or more and 200 or less each independently. is more preferably an integer independently from 0 to 100, and it is still more preferable that the sum of a, b, c, and d is 10 to 100. In addition, the presence order of each repeating unit added with a, b, c or d and enclosed in parentheses is an arbitrary order in the formula. Among these repeating units, -(OC ₄ F ₈ )- can be -(OCF ₂ CF ₂ CF ₂ CF ₂ )-, -(OCF(CF ₃ )CF ₂ CF ₂ )-, -(OCF ₂ CF(CF ₃ )CF ₂ )-,-(OCF ₂ CF ₂ CF(CF ₃ ))-,-(OC(CF ₃ ) ₂ CF ₂ )-,-(OCF ₂ C(CF ₃ ) ₂ )-,-(OCF (CF ₃ )CF(CF ₃ ))-, -(OCF(C ₂ F ₅ )CF ₂ )- and -(OCF ₂ CF(C ₂ F ₅ ))-, but preferably -( OCF ₂ CF ₂ CF ₂ CF ₂ )-. -(OC ₃ F ₆ )- can be any group in -(OCF ₂ CF ₂ CF ₂ )-, -(OCF(CF ₃ )CF ₂ )- and -(OCF ₂ CF(CF ₃ ))-, However, -(OCF ₂ CF ₂ CF ₂ )- is preferred. In addition, -(OC ₂ F ₄ )- may be any of -(OCF ₂ CF ₂ )- and -(OCF(CF ₃ ))-, but is preferably -(OCF ₂ CF ₂ )-.

In one aspect, R ^a is -(OC ₃ F ₆ ) _b - (wherein, b is an integer of 1 or more), preferably -(OCF ₂ CF ₂ CF ₂ ) _b -.

In another aspect, R ^a is -(OC ₂ F ₄ ) _c -(OCF ₂ ) _d -(wherein, c and d are each independently an integer of 1 or greater, and the subscript c or d is added and enclosed in parentheses The order of the repeating units in the formula is arbitrary), preferably -(OCF ₂ CF ₂ ) _c -(OCF ₂ ) _d -. In addition, in this embodiment, R ^a may contain trace amounts of -(OC ₄ F ₈ ) _a - (preferably -(OCF ₂ CF ₂ CF ₂ CF ₂ ) _a -) and -(OC ₃ F ₆ ) _b -( -(OCF ₂ CF ₂ CF ₂ ) _b -) is preferable, and it can be contained at a ratio of (a+b)/(a+b+c+d) of 0.3 or less, for example.

In the above formula (7), B ¹ and B ² are the same or different and represent a direct bond or a divalent organic group.

When the above-mentioned "divalent organic group" is used in this specification, it means the divalent group containing carbon. Such a divalent organic group is not particularly limited, and a divalent group obtained by further removing one hydrogen atom from a hydrocarbon group can be mentioned.

The above-mentioned "hydrocarbon group" means a group containing carbon and hydrogen when used in the present specification. Such a hydrocarbon group is not particularly limited, and examples thereof include hydrocarbon groups having 1 to 20 carbon atoms which may be substituted with one or more substituents, such as aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and the like. The aforementioned "aliphatic hydrocarbon group" may be any of linear, branched or cyclic, and may be any of saturated or unsaturated. In addition, the hydrocarbon group may contain one or more ring structures. It should be noted that such a hydrocarbon group may have one or more N, O, S, Si, amide, sulfonyl, siloxane, carboxyl, carboxyloxy, etc. at its terminal or in the molecular chain.

The substituent of the "hydrocarbon group" is not particularly limited, and examples thereof include: a halogen atom; a C _1-6 alkyl group, a C _2-6 alkenyl group, a C _{2 -6} alkynyl, C _3-10 cycloalkyl, C _3-10 unsaturated cycloalkyl, 5-10 membered heterocyclic group, 5-10 membered unsaturated heterocyclic group, C _6-10 aryl, 5-10 membered heteroaryl, etc.

The aforementioned B ¹ and B ² are preferably a direct bond, a C _1-20 alkylene group, or -(CH ₂ ) _s -X"-(CH ₂ ) _t -. In the above formula, X" represents -O-, or -(Si(R ^d ) ₂ O) _v -or -O-(CH ₂ ) _u -(Si(R ^d ) ₂ O) _v -(wherein, R ^d independently represents C ₁ in each occurrence _-6 alkyl, v is an integer of 1 to 100, u is an integer of 1 to 20), preferably -O-. s is an integer of 1-20, Preferably it is an integer of 1-3, More preferably, it is 1 or 2. t is an integer of 1-20, Preferably it is an integer of 2-3. These groups may be substituted with one or more substituents selected from fluorine atoms and C _1-3 alkyl groups.

As specific examples of the above ^- mentioned B1 and ^B2 , in addition to direct bonding, for example:

-CH ₂ O(CH ₂ ) ₃ -,

-CH ₂ O(CH ₂ ) ₆ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ OSi(CH ₃ ) ₂ (CH ₂ ) ₂ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ OSi(CH ₃ ) ₂ OSi(CH ₃ ) ₂ (CH ₂ ) ₂ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ O(Si(CH ₃ ) ₂ O) ₂ Si(CH ₃ ) ₂ (CH ₂ ) ₂ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ O(Si(CH ₃ ) ₂ O) ₃ Si(CH ₃ ) ₂ (CH ₂ ) ₂ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ O(Si(CH ₃ ) ₂ O) ₁₀ Si(CH ₃ ) ₂ (CH ₂ ) ₂ -,

-CH ₂ O(CH ₂ ) ₃ Si(CH ₃ ) ₂ O(Si(CH ₃ ) ₂ O) ₂₀ Si(CH ₃ ) ₂ (CH ₂ ) ₂ -etc.

In the above formula (7), among the groups represented by A ¹ and A ² , Y a in the group: Y ^a _3-k Q _k Si- represents ^a hydroxyl group, a hydrolyzable group, or a hydrocarbon group. The hydroxyl group is not particularly limited as long as it is a group produced by hydrolysis of a hydrolyzable group.

The above "hydrolyzable group", when used in the present specification, refers to a group that can be detached from the main skeleton of the compound by a hydrolysis reaction. Such a hydrolyzable group is not particularly limited, and examples thereof include -OR ^e , -OCOR ^e , -ON=C(R ^e ) ₂ , -N(R ^e ) ₂ , -NHR ^e , halogen atoms (these In the formula, R ^e independently represents a substituted or unsubstituted C _1-3 alkyl) and the like in each occurrence.

The above-mentioned Y ^a is preferably hydroxyl, -O(R ^f ) (in the formula, R ^f represents C _1-12 alkyl, preferably represents C _1-6 alkyl, more preferably represents C _1-3 alkyl), C _{1- 12} alkyl, C _2-12 alkenyl, C _2-12 alkynyl or phenyl, more preferably -OCH ₃ , -OCH ₂ CH ₃ , -OCH(CH ₃ ) ₂ . These groups may be substituted with, for example, one or more substituents selected from a fluorine atom, a C _1-6 alkyl group, a C _2-6 alkenyl group, and a C _2-6 alkynyl group.

In the above formula (7), Q in the group: Y ^a _3-k Q _k Si- represents -Z ^a -SiR ^b _j R ^c _3-j .

Said Z ^a each independently represents a divalent organic group in each appearance.

The aforementioned Z ^a preferably does not contain a group forming a siloxane bond with the Si atom at the end of the molecular main chain in formula (7).

The above-mentioned Z ^a is preferably a C _1-6 alkylene group or -(CH ₂ ) _s' -O-(CH ₂ ) _t' - (wherein, s' is an integer of 1 to 6, and t' is an integer of 1 to 6 Integer), more preferably C _1-3 alkylene. These groups may be substituted with, for example, one or more substituents selected from fluorine atoms, C _1-6 alkyl groups, C _2-6 alkenyl groups, and C _2-6 alkynyl groups.

The above-mentioned R ^b independently represents a hydroxyl group or a hydrolyzable group in each occurrence. Preferably, R ^b is -OR ^g (in the formula, R ^g represents a substituted or unsubstituted C _1-3 alkyl group, more preferably represents a methyl group).

The above-mentioned R ^c independently represents a C _1-22 alkyl group or Q' in each occurrence. The aforementioned Q' has the same meaning as Q.

The aforementioned j in each of Q and Q' is independently an integer selected from 0 to 3, and the total of j is 1 or more. When the aforementioned j in each Q or Q' is 0, Si in Q or Q' does not have a hydroxyl group or a hydrolyzable group. Therefore, the sum of j above must be at least 1 or more.

In Q' at the end of the -Q-Q' _0-5 chain bonded to the Si atom at the end of the molecular main chain having a perfluoropolyether group, the above n is preferably 2, more preferably 3.

In the case where at least one of R ^c in the above-mentioned Q is Q′, there are two or more Si atoms linearly connected via Z groups in Q. The number of such Si atoms linearly connected via the Z group is five at most.

In one aspect, the number of Si atoms linearly connected via the Z ^a group in Q is one (that is, only one Si atom exists in Q) or two.

In the above formula (7), k is an integer selected from 1 to 3, preferably 2 or more, and more preferably 3. By setting k to 3, the bond with the base material becomes strong, and high abrasion resistance can be obtained.

In one embodiment, the PFPE compound used in the present invention is a compound represented by formula (7) in which R ^c in Q is a C _1-22 alkyl group.

In one embodiment, the PFPE compound used in the present invention is a compound represented by formula (7) in which at least one of R ^c in Q is Q'.

The PFPE compound represented by the above formula (7) is not particularly limited, and may have an average molecular weight of 5×10 ² to 1×10 ⁵ . In such a range, it is preferable to have an average molecular weight of 1,000 to 30,000 from the viewpoint of abrasion resistance. In the present invention, the "average molecular weight" is a number average molecular weight, and the "average molecular weight" is a value measured by ¹⁹ F-NMR.

In the coating composition of the present invention, when a PFPE compound is blended, in order to sufficiently exert the effect of improving the abrasion resistance, the blending amount of the PFPE compound is preferably relative to 100 wt. The part is about 1 to 20 parts by weight.

The application object of the coating composition of the present invention is not particularly limited, and it can form a coating film with good abrasion resistance and excellent waterproof and moisture-proof performance on various substrates such as plastics, metals, and ceramics. Especially in the case of processing electronic parts including connectors, frames, printed circuit boards, semiconductors, etc., by using the coating composition of the present invention, a solvent with low chemical aggressiveness can be used to form a coating with excellent abrasion resistance. Excellent waterproof and moisture-proof coating, therefore, can give good waterproof and moisture-proof performance without inhibiting the performance of electronic parts.

The treatment method using the coating composition of the present invention is not particularly limited, as long as the coating composition of the present invention is brought into contact with the object to be treated. Usually, after the object to be treated is immersed in the coating composition of the present invention, it may be dried in an atmosphere with a humidity of about 20% to 70% or higher. In addition, a method of bringing the coating composition of the present invention into contact with an object to be treated by methods such as brush coating, spray coating, and spin coating can also be utilized.

Thus, the alkoxysilyl group introduced into the polymer terminal or side chain of the fluorine-containing polymer contained in the coating composition of the present invention is hydrolyzed by moisture in the atmosphere, converted into a silanol group, and reacted with the substrate. , so that the adhesion is improved. In addition, only the silanol groups reacted with the base material are condensed to form a two-dimensional or three-dimensional crosslink to form a strong film.

The temperature at the time of treatment is not particularly limited, and usually it is sufficient to perform the treatment at room temperature. The treatment time is also not particularly limited, and for example, in the case of the immersion method, the immersion time may be set to about 1 second to 24 hours.

In addition, in order to form a coating having higher abrasion resistance, it is preferable to wash the substrate with acetone, hydrofluoroether, etc. to remove oil from the surface of the substrate before treating with the coating composition of the present invention, and then dry it. Furthermore, in addition to the above cleaning, pretreatment with UV ozone, oxygen plasma, etc. can be performed to further improve the abrasion resistance of the coating.

In addition, before the treatment with the coating composition of the present invention, if necessary, primer treatment is applied to the object to be treated, thereby improving the adhesion of the coating film formed by the coating composition and further improving the abrasion resistance. . What is necessary is just to perform a primer treatment on the conditions similar to the primer treatment at the time of using a silane coupling agent according to a conventional method.

The effect of the invention

According to the waterproof-moisture-proof coating composition of the present invention, a waterproof and moisture-proof coating excellent in abrasion resistance can be formed on various substrates. In particular, when hydrofluoroether is used as a solvent, a good waterproof and moisture-proof coating can be formed without chemically attacking the substrate and without causing adverse effects on the environment.

Furthermore, when a PFPE compound is blended, the smoothness of the coating film formed of the fluorine-containing polymer is improved, and the abrasion resistance is greatly improved.

Therefore, according to the water-repellent-moisture-proof coating composition of the present invention, especially in the case of electronic parts as the processing object, it is possible to impart good waterproof properties with abrasion resistance without inhibiting the performance of the electronic parts. , Moisture-proof performance.

Description of drawings

1 is a graph showing the relationship between the immersion time in HFE7200 and the ratio of the static contact angle to water to the initial contact angle in Examples 1 to 6 and Comparative Examples 1 to 3;

2 is a graph showing the relationship between the number of times of wiping and the ratio of the static contact angle to water to the initial contact angle in Examples 7-8 and Comparative Examples 4-6;

3 is a graph showing the relationship between the number of abrasions and the ratio of the static contact angle to water to the initial contact angle in Examples 11 to 13 and Comparative Example 10;

4 is a graph showing the relationship between the number of abrasions and the ratio of the static contact angle to water to the initial contact angle in Examples 14 to 16 and Comparative Examples 11 to 13.

detailed description

Hereinafter, the present invention will be described in more detail with reference to production examples and examples.

Production example 1 (Rf(C6)α-Cl acrylate/MPS=100/5.21 (weight ratio) polymer)

Charge α-(perfluorohexyl) ethyl chloroacrylate (CH ₂ ═C(Cl)COOCH ₂ CH ₂ C ₆ F ₁₃ : sometimes abbreviated as “Rf(C6) α-Cl acrylate” in the four-necked flask ) 35g, mercaptopropyltrimethoxysilane (hereinafter sometimes abbreviated as "MPS") 1.824g, and perfluorohexyl methyl ether (C ₂ F ₅ CF(OCH ₃ )C ₃ F ₇ : sometimes abbreviated as "HFE7300" ) 66g, purged with nitrogen for 10 minutes, and heated to 80°C. Here, 0.127 g of azobisisobutyronitrile (hereinafter, may be abbreviated as "AIBN") was charged and reacted for 6 hours.

After cooling to room temperature, the fluoropolymer was precipitated with methanol and dried under reduced pressure. This was diluted with perfluorobutyl ethyl ether (C ₄ F ₉ OC ₂ H ₅ : sometimes abbreviated as "HFE7200") to prepare a solution having a predetermined concentration used in Examples described later.

When the molecular weight was measured by GPC using a fluorine-based solvent [HCFC225/hexafluoroisopropanol=90/10 (weight)] as an eluent, the weight average molecular weight was 22,100.

Production example 2 (Rf(C6)α-Cl acrylate/MPS=100/3.08 (weight ratio) polymer)

Except that the amount of MPS used was 1.079 g, a fluorine-containing polymer was synthesized in the same manner as in Production Example 1, and a HFE7200 solution of a predetermined concentration used in Examples described later was prepared. The weight average molecular weight of the obtained polymer was 36,900.

Production example 3 (Rf(C6)α-Cl acrylate/MPS=100/1.04 (weight ratio) polymer)

Except that the amount of MPS used was 0.365 g, a fluoropolymer was synthesized in the same manner as in Production Example 1, and a HFE7200 solution of a predetermined concentration used in Examples described later was prepared. The weight average molecular weight of the obtained polymer was 42,300.

Production Example 4 (Rf(C6) methacrylate/MPS=100/1.04 (weight ratio) polymer)

In Production Example 1, (perfluorohexyl)ethyl methacrylate (CH ₂ =C(CH ₃ )COOCH ₂ CH ₂ C ₆ F ₁₃ : hereinafter sometimes abbreviated as "Rf(C6) methacrylate") was used In place of Rf(C6)α-Cl acrylate, except that the usage-amount of MPS was 0.365 g, the HFE7200 solution of the predetermined density|concentration used in the Example mentioned later was prepared by the method similar to manufacture example 1. The weight average molecular weight of the obtained polymer was 6,800.

Production Example 5 (Rf(C6) methacrylate/MPS=100/0.45 (weight ratio) polymer)

Except that the amount of MPS used was 0.159 g, a fluorine-containing polymer was synthesized in the same manner as in Production Example 4, and an HFE7200 solution of a predetermined concentration used in Examples described later was prepared. The weight average molecular weight of the obtained polymer was 13,400.

Production Example 6 (Rf(C6) methacrylate/MPS=100/0.23 (weight ratio) polymer)

Except that the amount of MPS used was 0.080 g, a fluorine-containing polymer was synthesized in the same manner as in Production Example 4, and an HFE7200 solution of a predetermined concentration was prepared. The weight average molecular weight of the obtained polymer was 25,000.

Production Example 7 (Rf(C6) methacrylate/iBMA/MPS=100/14.58/1.424 (weight ratio) polymer)

60.24 g of Rf (C6) methacrylate, 8.78 g of isobornyl methacrylate (hereinafter sometimes abbreviated as iBMA), 0.858 g of MPS, and perfluorobutyl ethyl ether (C ₄ F ₉ OC ₂ H ₅ : hereinafter sometimes abbreviated as "HFE7200") 280.0 g, purged with nitrogen for 10 minutes, and heated to 70°C. Here, 0.298 g of AIBN was added and reacted for 6 hours.

After cooling to room temperature, a part of the reaction solution was taken out on an aluminum cup, and dried at 110° C. under normal pressure for 1 hour to calculate the resin solid content concentration of the polymer in the polymerization solution. Then, the polymerization solution was diluted with a predetermined amount of HFE7200 to prepare a solution having a predetermined concentration used in Examples described later.

When the molecular weight was measured by GPC in the same manner as in Production Example 1, the weight average molecular weight of the obtained polymer was 16,700.

Production Example 8 (Rf(C6) methacrylate/iBMA/MPS/TMSMA=100/14.58/1.507/2.383 (weight ratio) polymer)

30.72 g of Rf (C6) methacrylate, 4.48 g of iBMA, 0.463 g of MPS, and 3-(trimethoxysilyl)propyl methacrylate (hereinafter sometimes referred to as “TMSMA”) were placed in a four-necked flask. 0.732g, and HFE7200140.6g, purged with nitrogen for 10 minutes, and heated to 70°C. Here, 0.156 g of AIBN was added and reacted for 6 hours.

After cooling to room temperature, the resin solid content concentration of the polymer in the polymerization solution was calculated by the same method as in Production Example 7. Then, the polymerization solution was diluted with a predetermined amount of HFE7200 to prepare a solution having a predetermined concentration used in Examples described later.

When the molecular weight was measured by GPC in the same manner as in Production Example 1, the weight average molecular weight of the obtained polymer was 14,200.

Production Example 9 Rf (C6) methacrylate/iBMA/TMSMA=100/14.49/2.373 (weight ratio) polymer)

91.81 g of Rf (C6) methacrylate, 13.30 g of iBMA, 2.179 g of TMSMA, and 20.03 g of HFE72004 were placed in a four-necked flask, purged with nitrogen for 10 minutes, and heated to 70°C. Here, 0.464 g of AIBN was added and reacted for 6 hours.

After cooling to room temperature, the resin solid content concentration of the polymer in the polymerization solution was calculated by the same method as in Production Example 7. Then, the polymerization solution was diluted with a predetermined amount of HFE7200 to prepare a solution having a predetermined concentration used in Examples described later.

When the molecular weight was measured by GPC in the same manner as in Production Example 1, the weight average molecular weight of the obtained polymer was 118,800.

Comparative production example 1 (Rf(C6)α-Cl acrylate/MPS=100/0 (weight ratio) polymer)

A fluoropolymer was synthesized in the same manner as in Production Example 1 except that MPS was not used, and a HFE7200 solution of a predetermined concentration used in a comparative example described later was prepared. The weight average molecular weight of the obtained polymer was 171,900.

Comparative Production Example 2 (Rf(C6) methacrylate/MPS=100/0 (weight ratio) polymer)

A fluoropolymer was synthesized in the same manner as in Production Example 4 except that MPS was not used, and a HFE7200 solution of a predetermined concentration used in a comparative example described later was prepared. The weight average molecular weight of the obtained polymer was 269,600.

Comparative Production Example 3 (Rf(C8) methacrylate/MPS=100/0 (weight ratio) polymer)

_In Production Example ₁ , instead _of Rf(C6) _α- Cl acrylate was not used, except that MPS was not used, and the HFE7200 solution of the predetermined density|concentration used in the comparative example mentioned later was prepared by the method similar to manufacture example 1. The weight average molecular weight of the obtained polymer was 228,300.

Comparative Production Example 4 Rf (C6) methacrylate/iBMA/TMSMA=100/14.49/0 (weight ratio) polymer)

Except not using TMSMA, the fluorine-containing polymer was synthesized by the same method as Production Example 9, and the resin solid content concentration of the polymer after polymerization was calculated by the same method as Production Example 7. Then, the solution obtained by calculating the resin solid content concentration was diluted with HFE7200 to prepare a solution having a predetermined concentration used in Examples described later.

The weight average molecular weight of the obtained polymer was 115,000.

Examples 1-6 and Comparative Examples 1-3

A silicon wafer was used as an object to be processed, and was subjected to ultrasonic cleaning in acetone for 30 minutes, followed by immersion in HFE7200, followed by drying to perform pretreatment.

After the silicon wafer pretreated by the above-mentioned method was immersed in the HFE7200 solution (resin solid content concentration: 0.2% by weight) of each fluoropolymer obtained in Production Examples 1 to 6 and Comparative Production Examples 1 to 3, It was left to stand in the atmosphere (20° C., humidity 30%) for a whole day and night, and a test piece was produced.

Each of these test pieces was immersed in HFE7200 at room temperature (20° C.) for a predetermined period of time after measuring the static contact angle to water to determine the initial contact angle. Then, after being pulled up and left in the atmosphere for 1 minute, the static contact angle to water was measured, and the ratio to the initial contact angle was calculated to evaluate the durability against solvents. Table 1 and Table 2 below show the immersion time in HFE7200 and the ratio of the static contact angle to water to the initial contact angle, and Fig. 1 shows the immersion time in HFE7200 and the static contact angle to water relative to The ratio of the initial contact angle.

In addition, irregularities formed by cutting the thin film formed on the silicon wafer by the above-mentioned method with a paper knife were measured with a laser microscope VK-9710 (manufactured by KEYENCE Corporation), and the calculated film thickness was about 50 nm.

[Table 1]

[Table 2]

From the above results, it is clear that the coating liquids of Production Examples 1 to 6 obtained by dissolving and polymerizing a fluoroalkyl-containing acrylate in hydrofluoroether in the presence of MPS can form A water-repellent coating with excellent durability in solvent immersion.

Embodiment 7～8 and comparative example 4～6

Using the HFE7200 solutions of the respective fluoropolymers obtained in Production Examples 2 and 5 and the HFE7200 solutions of the respective fluoropolymers obtained in Comparative Production Examples 1 to 3, the silicon wafer was dipped in the same manner as in Example 1. , to make test pieces.

After measuring the static contact angle to water of each of these test pieces and obtaining the initial contact angle, the paper Wes (trade name: Kimwiper, manufactured by Nippon Paper Crecia) was installed in a friction tester (Imoto Seisakusho friction tester "resistant Abrasive testing machine 151E3 with specification ") bracket, wipe the surface for a specified number of times with a load of 100g, then measure the static contact angle to water, calculate the ratio to the initial contact angle, and compare the abrasion resistance relative to wiping Evaluation. Table 3 below shows the number of wiping times and the ratio of the static contact angle to water to the initial contact angle, and FIG. 2 shows the relationship between the number of wiping times and the ratio of the static contact angle to water to the initial contact angle in a graph.

[table 3]

From the above results, it was found that the coating liquids obtained in Production Examples 2 and 5 can form a water-repellent coating excellent in abrasion resistance against wiping.

Examples 9-10 and Comparative Examples 7-9

Using the HFE7200 solutions of the respective fluoropolymers obtained in Production Examples 2 and 5 and the HFE7200 solutions of the respective fluoropolymers obtained in Comparative Production Examples 1 to 3, the moisture resistance and rust resistance were evaluated by the following methods. Evaluation. The results are shown in Table 4 below.

*Evaluation method of moisture resistance

Moisture resistance was evaluated by moisture permeability (cup method, JIS Z0208). Moisture permeability (g/m ² ·day) is defined by the amount of water vapor passing through the moisture-proof film, and the smaller the value, the better the moisture-proof property.

As a test method, a moisture-permeable waterproof sheet for building materials (JIS A6111·2004 qualified product) was cut out into a circular shape (diameter 70mm) as a support sheet, and a 2% by weight HFE7200 solution of each fluoropolymer was prepared. , Form a film (thickness of about 100 nm) on the moisture-permeable waterproof sheet by spin coating method, and measure the moisture permeability. The transmittance of the support sheet alone is about 4000 g/m ² ·day.

*Evaluation method of rust resistance

Rust prevention performance was evaluated on the following conditions by the salt spray test (JIS Z2371).

The angle of the test piece: 20±5° relative to the vertical axis

Salt concentration: 5% by weight, pH 6.5 to 7.2

Spray temperature: 60±1℃

Using a JIS H3100 (C1100P) polished copper substrate (manufactured by Japan Testpanel Industries) with a size of 2.0×15×60 mm as a substrate, it was dipped once in a 2% HFE7200 solution of each fluoropolymer to form a film (film thickness about 100nm). After the salt spray, the appearance after 96 hours was evaluated in five stages of ◎ (no change at all), ○, △, ×, ×× (severe discoloration=untreated).

[Table 4]

From the above results, it was found that the coating liquids obtained in Production Examples 2 and 5 can form coatings excellent in moisture resistance and rust resistance.

In addition, the reason why the moisture resistance is good is not clear, but it is speculated that one of the contributing reasons is that the alkoxysilyl group at the end of the polymer crosslinks the polymer molecules and improves the adhesiveness between the polymer and the substrate.

Examples 11-13 and Comparative Example 10

Using the HFE7200 solution of each fluoropolymer obtained in Production Examples 7 to 9 and the HFE7200 solution of each fluoropolymer obtained in Comparative Production Example 4, the same method as in Example 1 was used to prepare a silicon wafer by immersion treatment. piece.

About each of these test pieces, the abrasion resistance was evaluated by the method similar to Examples 7-8 and Comparative Examples 4-6, making load into 500g, and making a friction block into steel wool. The following Table 5 shows the number of abrasions and the ratio of the static contact angle to water to the initial contact angle when the friction block is made of steel wool. Figure 3 shows the number of abrasions and the static contact angle to water relative to the initial The ratio of the contact angle.

[table 5]

From the above results, it is clear that the coating liquids obtained in Production Examples 7 to 9 can form a water-repellent coating excellent in abrasion resistance when steel wool is used as a friction block.

Examples 14-16 and Comparative Examples 11-13

The HFE7200 solution of the fluoropolymer obtained in Production Example 9 (resin solid content concentration: 2% by weight) and the HFE7200 solution of the fluoropolymer obtained in Comparative Production Example 4 (resin solid content concentration: 2% by weight) were prepared. In addition, the HFE7200 solution of these fluoropolymers and the HFE7200 solution of a compound having a perfluoropolyether (PFPE) skeleton (resin solid content concentration 2% by weight) were mixed at a weight ratio of 90/10 to prepare a resin solid content concentration of 2 % by weight solution. In addition, as the compound having a perfluoropolyether (PFPE) skeleton, a silane compound having a PFPE skeleton (Daikin Industries, Optool DSX) and unmodified PFPE oil (Daikin Industries, Demnum S-20) were used. (In the following, Optool DSX is sometimes referred to as DSX, and Demnum S-20 is referred to as S-20.)

Using these solutions, a silicon wafer was dip-treated in the same manner as in Example 1 to prepare a test piece. For each of the obtained test pieces, the abrasion resistance was evaluated by the same method as in Examples 7-8 and Comparative Examples 4-6, with a load of 250 g and a friction block made of steel wool. Table 6 below shows the number of abrasions and the ratio of the static contact angle to water to the initial contact angle when the friction block is made of steel wool, and Fig. 4 shows the number of abrasions and the static contact angle to water to the initial contact angle in a graph ratio relationship.

[Table 6]

From the above results, it is clear that the test pieces (Examples 14 and 15) prepared with the mixed solution of fluoropolymer and PFPE compound can form steel wires as compared with Example 16 without PFPE and Comparative Production Examples 11 to 13. A water-repellent coating that is excellent in abrasion resistance when cotton is used as a friction member.

Example 17 and Comparative Example 14

After charging a commercially available smartphone (Galaxy S II manufactured by Samsung Electronics), cut off the power supply, and stand vertically with the micro USB part facing up. The inside of the plug fitting port of the micro USB socket is filled with the coating agent of Production Example 9 or Comparative Production Example 4 adjusted to various concentrations (0.1, 0.2, 0.5, 1, 2, 5, 10% by weight) Immediately after that, the application agent is turned over so that the opening of the micro USB faces downward, and the application agent is discharged, whereby the inside of the plug fitting port is applied. After the treatment, the following tests were carried out after the treatment was carried out in an environment with a temperature of 25° C. and a humidity of 60% for 1 hour.

·Initial evaluation

The degree of initial conductivity was evaluated by measuring the contact resistance of the electrodes (5 electrodes). When the contact resistances of all five electrodes were less than 50 mΩ, the electrical conductivity was evaluated as (◯), and when even one electrode was 50 mΩ or more, it was evaluated as poor conduction (×). Next, stand vertically with the micro USB facing upwards, fill the inside of the plug fitting opening with a dropper, and immediately drop the micro USB on the table from a height of 1 cm to drain the tap water. The splashing of water remaining inside the plug fitting port (water repellency) was visually judged by the following criteria. The higher the water repellency, the less water droplets remain inside the plug fitting port, which means that electric field corrosion of electrodes is less likely to occur.

◎: Very good bounce (contact angle around 110°)

○: Good bounce (contact angle around 100°)

△: Pop open (contact angle is about 90°)

×: (Contact angle around 50-80°)

××: (Contact angle below 50°)

·Plugging test

The contact resistance was measured after 5,000 times of plugging and unplugging the waterproof micro USB. Next, water repellency was evaluated in the same manner as in the initial stage. Next, turn on the power of the smartphone, stand vertically with the micro USB facing up, fill the inside of the plug fitting port with tap water with a dropper, and leave it for 10 minutes with the water in it. With the micro USB facing down, drop it on the table from a height of 1cm, and tap water will drain from it. The presence or absence of electric field corrosion was determined by observing the degree of discoloration of the USB electrodes in the following five stages with a solid microscope (magnification: 30 times).

◎: No discoloration at all

○: slightly discolored

△: slightly discolored

×: discoloration

××: severe discoloration

The above test results are shown in Table 7 below.

[Table 7]

From the above results, it is clear that when the coating agent of Production Example 9 was used, compared with the coating agent of Comparative Production Example 4, good water repellency and electric field corrosion were obtained. In particular, the coating agent of Production Example 9 ensured initial electrical conductivity when the solid content concentration of the coating agent was in the range of 0.2 to 2% by weight, had good water repellency after the plug-in test, and was less likely to cause electric field corrosion.

Claims (15)

1. permanent seal cooling waterproof-moisture resistance coating composition in the connector of electronic component for forming permanent seal cooling waterproof-anti- Purposes in moist overlay film, it is characterised in that：

Permanent seal cooling waterproof-moisture resistance the coating composition includes (I) fluoropolymer and (II) fluorine series solvent, also, solid Constituent concentration is 0.2~2 weight %,

Wherein, described (I) fluoropolymer is to carry out the acrylate containing fluoroalkyl obtained from radical polymerization to polymerize Thing, is somebody's turn to do the fluoroalkyl that there is the acrylate containing fluoroalkyl the direct or organic group via divalent ester linkage is carried out with carboxyl, And can have substituent at α,

(I) fluoropolymer includes the polymer shown in following (1) or (2)：

(1) acrylate and the free radical polymerization monomer containing alkoxysilyl by making to contain fluoroalkyl comprising this Monomer component carry out radical polymerization obtained from polymer,

(2) carried out certainly by the acrylate in the presence of the mercaptan containing alkoxysilyl, making this contain fluoroalkyl The polymer as obtained from polymerizeing base.

2. purposes as claimed in claim 1, it is characterised in that：

Acrylate containing fluoroalkyl is the compound shown in following formulas (1),

In formula, X is hydrogen atom, fluorine atom, chlorine atom, bromine atoms, iodine atom, CFX¹X²Base, cyano group, carbon number 1~21 it is straight Chain or the fluoroalkyl of branched, substitution or non-substituted benzyl, substitution or non-substituted phenyl or carbon number 1 ~20 straight-chain or the alkyl of branched, wherein, X¹And X²It is hydrogen atom, fluorine atom or chlorine atom identical or differently, Y is Direct Bonding, can have oxygen atom carbon number 1~10 fatty group, can have oxygen atom carbon number 6~ 10 aromatic series base, can have oxygen atom carbon number 6~10 annular aliphatic base, can have the carbon of oxygen atom former Aromatic-aliphatic the base ,-CH of subnumber 6~10₂CH₂N(R¹)SO₂ ^-Base ,-CH₂CH(OY¹)CH₂ ^-Base or-(CH₂)_nSO₂ ^-Base, its In, R¹For the alkyl of carbon number 1~4, Y¹For hydrogen atom or acetyl group, n is the straight chain that 1~10, Rf is carbon number 1~20 The fluoroalkyl of shape or branched.

3. purposes as claimed in claim 2, it is characterised in that：

Acrylate containing fluoroalkyl is that in formula (1), Rf is the straight-chain of carbon number 4~6 or the fluothane of branched Base, X are the atom or group, α substituted carboxylates beyond hydrogen.

4. such as purposes according to any one of claims 1 to 3, it is characterised in that：

(1) fluoropolymer shown in,

The usage amount of free radical polymerization monomer containing alkoxysilyl contains fluothane relative to as monomer component The parts by weight of acrylate 100 of base are 0.1~20 parts by weight, and also to use high softening-point monomer to be obtained as monomer component The copolymer arrived；

(2) fluoropolymer shown in,

The usage amount of mercaptan containing alkoxysilyl is relative to the acrylate containing fluoroalkyl as monomer component 100 parts by weight are 0.1~5 parts by weight, and also to use high softening-point monomer as copolymer obtained from monomer component,

Also, fluorine series solvent is hydrofluoroether.

5. such as purposes according to any one of claims 1 to 3, it is characterised in that：

Fluoropolymer is the acrylic acid by making this contain fluoroalkyl in the presence of the mercaptan containing alkoxysilyl Ester carries out polymer obtained from radical polymerization, and also to use the free-radical polymerised list containing alkoxysilyl Body is used as copolymer obtained from monomer component.

6. such as purposes according to any one of claims 1 to 3, it is characterised in that：

Free radical polymerization monomer containing alkoxysilyl is the compound shown in formula (2),

In formula, R²、R³And R⁴Alkyl or the alkoxy of carbon number 1~4 identical or differently for carbon number 1~4, R²、R³ And R⁴In at least one be alkoxy, R⁵For the group containing free-radical polymerised unsaturated bond.

7. such as purposes according to any one of claims 1 to 3, it is characterised in that：

Mercaptan containing alkoxysilyl is the compound shown in formula (3),

In formula, R⁷、R⁸And R⁹Alkyl or the alkoxy of carbon number 1~4 identical or differently for carbon number 1~4, R⁷、R⁸ And R⁹In at least one be alkoxy, R¹⁰For the alkylidene of the straight-chain of carbon number 1~12.

8. purposes as claimed in claim 4, it is characterised in that：

High softening-point monomer be the glass transition temperature of homopolymer or fusing point formed by the high softening-point monomer be 100 DEG C with On monomer.

9. such as purposes according to any one of claims 1 to 3, it is characterised in that：

Fluoropolymer is the polymer with the structure division shown in following formulas (5),

In formula, X is hydrogen atom, fluorine atom, chlorine atom, bromine atoms, iodine atom, CFX¹X²Base, cyano group, carbon number 1~21 it is straight Chain or the fluoroalkyl of branched, substitution or non-substituted benzyl, substitution or non-substituted phenyl or carbon number 1 ~20 straight-chain or the alkyl of branched, wherein, X¹And X²It is hydrogen atom, fluorine atom or chlorine atom identical or differently, Y is Direct Bonding, can have oxygen atom or sulphur atom carbon number 1~10 fatty group, can have the carbon of oxygen atom The aromatic series base of atomicity 6~10, can have oxygen atom carbon number 6~10 annular aliphatic base, can have oxygen Aromatic-aliphatic the base ,-CH of the carbon number 6~10 of atom₂CH₂N(R¹)SO₂ ^-Base ,-CH₂CH(OY¹)CH₂ ^-Base or-(CH₂)_nSO₂ ^-Base, wherein, R¹For the alkyl of carbon number 1~4, Y¹For hydrogen atom or acetyl group, n be 1~10, Rf be carbon number 1~ 20 straight-chain or the fluoroalkyl of branched, R²、R³And R⁴It is the alkyl or carbon number of carbon number 1~4 identical or differently 1~4 alkoxy, R²、R³And R⁴In at least one be alkoxy, R^5’For from containing free-radical polymerised unsaturated bond The group of the divalent of group, R¹¹For H or CH₃, R¹²For be 4~20 with carbon number and carbon atom relative to hydrogen atom ratio For the group of more than 0.58 saturated alkyl, l, m and n are respectively more than 1 integer, and adding up to for l, m and n makes weight average molecular weight For 3,000~500,000 numerical value, in addition, the presence order of each repeat unit bracketed with l, m and n and with parantheses exists It is random order in formula.

10. such as purposes according to any one of claims 1 to 3, it is characterised in that：

Fluoropolymer is the thing included in the polymer in end with alkoxysilyl shown in following formulas (6) Matter,

In formula, X is hydrogen atom, fluorine atom, chlorine atom, bromine atoms, iodine atom, CFX¹X²Base, cyano group, carbon number 1~21 it is straight Chain or the fluoroalkyl of branched, substitution or non-substituted benzyl, substitution or non-substituted phenyl or carbon number 1 ~20 straight-chain or the alkyl of branched, wherein, X¹And X²It is hydrogen atom, fluorine atom or chlorine atom identical or differently, Y is Direct Bonding, can have oxygen atom or sulphur atom carbon number 1~10 fatty group, can have the carbon of oxygen atom The aromatic series base of atomicity 6~10, can have oxygen atom carbon number 6~10 annular aliphatic base, can have oxygen Aromatic-aliphatic the base ,-CH of the carbon number 6~10 of atom₂CH₂N(R¹)SO₂ ^-Base ,-CH₂CH(OY¹)CH₂ ^-Base or-(CH₂)_nSO₂ ^-Base, wherein, R¹For the alkyl of carbon number 1~4, Y¹For hydrogen atom or acetyl group, n be 1~10, Rf be carbon number 1~ 20 straight-chain or the fluoroalkyl of branched, R⁷、R⁸And R⁹It is the alkyl or carbon number of carbon number 1~4 identical or differently 1~4 alkoxy, R⁷、R⁸And R⁹In at least one be alkoxy, R¹⁰For the alkylidene of the straight-chain of carbon number 1~12, n To make the numerical value that weight average molecular weight is 3,000~500,000.

11. such as purposes according to any one of claims 1 to 3, it is characterised in that：

It also contains the compound with perfluoropolyether backbone.

12. purposes as claimed in claim 11, it is characterised in that：

The content of compound with perfluoropolyether backbone is 1~20 parts by weight relative to the parts by weight of fluoropolymer 100.

13. permanent seal cooling waterproof-moisture resistance coating composition in the connector of electronic component for forming permanent seal cooling waterproof-anti- Purposes in moist overlay film, it is characterised in that：

Permanent seal cooling waterproof-moisture resistance the coating composition includes (I) fluoropolymer and (II) hydrofluoroether, also, solid into It is 0.2~2 weight % to divide concentration,

Wherein, described (I) fluoropolymer is to carry out the acrylate containing fluoroalkyl obtained from radical polymerization to polymerize Thing, is somebody's turn to do the fluoroalkyl that there is the acrylate containing fluoroalkyl the direct or organic group via divalent ester linkage is carried out with carboxyl, And there is substituent at α,

(I) fluoropolymer includes the polymer shown in following (1) or (2)：

(1) acrylate and the free radical polymerization monomer containing alkoxysilyl by making to contain fluoroalkyl comprising this Monomer component carry out polymer obtained from radical polymerization, and also to use high softening-point monomer as monomer component Obtained copolymer, also, the free radical polymerization monomer containing alkoxysilyl usage amount relative to as monomer The parts by weight of acrylate 100 containing fluoroalkyl of composition are 0.1~20 parts by weight；

(2) carried out certainly by the acrylate in the presence of the mercaptan containing alkoxysilyl, making this contain fluoroalkyl The polymer as obtained from polymerizeing base, and also to use high softening-point monomer as copolymer obtained from monomer component, and And, the usage amount of the mercaptan containing alkoxysilyl is relative to the acrylate containing fluoroalkyl as monomer component 100 parts by weight are 0.1~5 parts by weight；

Acrylate containing fluoroalkyl is shown in following formulas (1), α substituted carboxylates,

In formula, X is fluorine atom, chlorine atom, bromine atoms, iodine atom, CFX¹X²Base, cyano group, the straight-chain of carbon number 1~21 or Fluoroalkyl, substitution or the non-substituted benzyl of person's branched, substitution or non-substituted phenyl or carbon number 1~20 The alkyl of straight-chain or branched, wherein, X¹And X²It is identical or differently hydrogen atom, fluorine atom or chlorine atom, Y is direct key Close, can have oxygen atom carbon number 1~10 fatty group, can have oxygen atom carbon number 6~10 virtue Fragrant race's base, can have oxygen atom carbon number 6~10 annular aliphatic base, can have oxygen atom carbon number 6 ~10 aromatic-aliphatic base ,-CH₂CH₂N(R¹)SO₂ ^-Base ,-CH₂CH(OY¹)CH₂ ^-Base or-(CH₂)_nSO₂ ^-Base, wherein, R¹For The alkyl of carbon number 1~4, Y¹For hydrogen atom or acetyl group, n is the straight-chain or side chain that 1~10, Rf is carbon number 4~6 The fluoroalkyl of shape.

14. a kind of forming method of permanent seal cooling waterproof-moisture proof film, it is characterised in that：

It includes making the connector of electronic component apply with the permanent seal cooling waterproof any one of claim 1~13-moisture resistance The process for applying composition contact.

15. a kind of connector of electronic component, it is characterised in that：

It is formed with waterproof-damp proof as permanent seal cooling waterproof-moisture resistance coating composition any one of claim 1~13 Property overlay film.