WO2015190526A1 - Curable composition containing perfluoropolyether having silyl group - Google Patents

Abstract

[Problem] To provide a curable composition which is soluble in various non-fluorine organic solvents in comparison to conventional curable compositions and provides a cured film having a surface with excellent antifouling properties and lubricity, and which is useful as a hard coat layer-forming material. [Solution] A curable composition that contains a perfluoropolyether A wherein an alkoxysilyl group is bonded to each end of a molecular chain, which contains a poly(oxyperfluoroalkylene) group, via a poly(oxyalkylene) group and an additional suitable linking group; and an antifouling base having an antifouling layer that is formed from this curable composition.

Description

Curable composition containing perfluoropolyether having a silyl group

The present invention relates to a curable composition useful as a material for forming a hard coat layer applied to the surface of various display elements such as a touch panel display and a liquid crystal display.

A large number of products in which a touch panel is mounted on a flat panel display such as a personal computer, a mobile phone, a mobile game machine, and an ATM have been commercialized. In particular, with the advent of smartphones and tablet PCs, the number of capacitive touch panels having a multi-touch function is rapidly increasing.

By the way, the capacitive touch panel is operated by touching it with a human finger. For this reason, fingerprints are attached to the surface of the touch panel every time an operation is performed, causing problems that the visibility of the image on the display is remarkably impaired and the appearance of the display is impaired. The fingerprint contains moisture derived from sweat and oil derived from sebum, and it is strongly desired to impart water repellency and oil repellency to the hard coat layer on the display surface in order to prevent both of them from adhering. ing.

In addition, the touch panel display of many smartphones employs a multi-touch function, which allows you to use multiple fingers to expand (pinch out) or reduce (pinch in) the screen, or to flick a finger in a certain direction on the screen. And swipe operation. In order to obtain a smooth tactile sensation without being caught by such finger movement, there is a demand for slipperiness when the display surface is touched with a finger.

From such a viewpoint, it is desired that the surface of the touch panel display has slipperiness when operated with a finger in addition to antifouling properties against fingerprints and the like. However, in a capacitive touch panel, since a person touches it with a finger every day, even if the initial antifouling property and slipperiness reach a considerable level, their functions often deteriorate during use. Therefore, the antifouling property and the durability of slipperiness during use are problems.

A thin tempered glass called a cover glass is used on the surface of these touch panel displays. In order to impart scratch resistance, antifouling properties, and slipperiness on the cover glass surface, a pole of about several nanometers by a perfluoropolyether silane compound having a silane moiety capable of binding to a silanol group on the cover glass surface. A thin antifouling layer is formed. Examples of a method for forming these antifouling layers include vacuum deposition of a perfluoropolyether silane compound, and a method of diluting the compound with a fluorine-based solvent and applying it by spraying.

Although these perfluoropolyether silane compounds have a high antifouling function, their high fluorine content makes it difficult to dissolve them in non-fluorinated organic solvents used in general paints. Therefore, it is necessary to use an expensive fluorine-based solvent as compared with an organic solvent, and it is desired that the solvent can be diluted with a cheaper non-fluorine-based organic solvent.
Under such circumstances, a technique of diluting a perfluoropolyether silane compound having a silane moiety with an organic solvent and applying it to a glass surface is disclosed (Patent Document 1).

JP 2010-106075 A

However, even the perfluoropolyether silane compound described in Patent Document 1 has a very small amount of a non-fluorine organic solvent that can be dissolved, which is not sufficient. Furthermore, the problem is that the antifouling property and slipperiness of the antifouling layer formed from the compound are insufficient.

As a result of intensive investigations to achieve the above object, the present inventors have determined that alkoxysilyl groups are bonded to both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and a linking group. The perfluoropolyether to which the group is bonded can be diluted with various non-fluorinated organic solvents, and the antifouling layer formed by applying them to the glass surface has high antifouling properties and slipperiness. As a result, the present invention has been completed.

That is, the present invention provides, as a first aspect, (a) an alkoxysilyl group is bonded to each end of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and a more suitable linking group. The present invention relates to a curable composition comprising bound perfluoropolyether A.
As a second aspect, the present invention relates to the curable composition according to the first aspect, in which the poly (oxyalkylene) group is a poly (oxyethylene) group.
As a third aspect, the poly (oxyperfluoroalkylene) group is a group having — [OCF ₂ ] — and — [OCF ₂ CF ₂ ] — as repeating units, according to the first aspect or the second aspect. The present invention relates to a curable composition.
As a fourth aspect, the present invention relates to the curable composition according to any one of the first aspect to the third aspect, in which the alkoxysilyl group is a group represented by the formula [1].

(Wherein R ¹ represents an alkyl group having 1 to 5 carbon atoms, R ² represents an alkyl group having 1 to 5 carbon atoms or a phenyl group, and a represents an integer of 1 to 3)
As a fifth aspect, the present invention relates to the curable composition according to the fourth aspect, wherein the perfluoropolyether A is a compound represented by the formula [2].

(In the formula, R ¹ and R ³ each independently represents an alkyl group having 1 to 5 carbon atoms, and R ² and R ⁴ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. , A and b each independently represent an integer of 1 to 3, L ^{1 to} L ⁴ each independently represents an alkylene group having 1 to 5 carbon atoms, and X ¹ and X ² each independently represent: —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein m and n are 2 to 40 PFPE1 represents a group having a poly (oxyperfluoroalkylene) structure as a core and a terminal structure linked to an oxyalkylene group on both sides thereof.
As a sixth aspect, (b) a perfluoroalkyl group having an alkoxysilyl group bonded to each end of a molecular chain containing a poly (oxyperfluoroalkylene) group via a linking structure having no poly (oxyalkylene) structure. It is related with the curable composition as described in any one of the 1st viewpoint thru | or 5th viewpoint containing the fluoro polyether B.
As a seventh aspect, the present invention relates to the curable composition according to the sixth aspect, wherein the perfluoropolyether B is a compound represented by the formula [3].

(In the formula, R ⁵ and R ⁷ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ⁶ and R ⁸ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. , R and s each independently represent an integer of 1 to 3, L ⁵ and L ⁶ each independently represent an alkylene group having 1 to 5 carbon atoms, and X ³ and X ⁴ each independently represent: —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein PFPE2 is a poly (oxyperfluoroalkylene) structure Represents a group having a terminal structure linked to X ³ or X ⁴ on the both sides thereof.)
As an eighth aspect, the present invention relates to the curable composition according to the sixth aspect or the seventh aspect, wherein the content of the perfluoropolyether B is 50% by mass or less of the perfluoropolyether A.
As a ninth aspect, the present invention further relates to the curable composition according to any one of the first aspect to the eighth aspect, further including (c) a solvent.
As a 10th viewpoint, it is related with the cured film obtained from the curable composition as described in any one of a 1st viewpoint thru | or a 9th viewpoint.
As an eleventh aspect, an antifouling substrate comprising an antifouling layer on at least one surface of an inorganic oxide substrate or a metal substrate, wherein the antifouling layer is the inorganic oxide substrate or the metal substrate. The present invention relates to an antifouling substrate formed by heating and curing a coating film made of the curable composition according to any one of the first to ninth aspects formed above.
A twelfth aspect is an antifouling substrate comprising a primer layer and an antifouling layer in this order on at least one surface of an inorganic oxide substrate or a metal substrate, the primer layer comprising the inorganic oxide group It is formed by heating and curing a coating film comprising all or a partial hydrolysis-condensation product of tetraalkoxysilane formed on a material or metal substrate, and the antifouling layer is formed on the primer layer. The present invention also relates to an antifouling substrate formed by heating and curing a coating film of the curable composition according to any one of the first to ninth aspects.
A thirteenth aspect relates to the antifouling substrate according to the twelfth aspect, wherein the primer layer has a thickness of 1 to 200 nm.
As a fourteenth aspect, the present invention relates to the antifouling substrate according to any one of the eleventh aspect to the thirteenth aspect, wherein the antifouling layer has a thickness of 1 to 50 nm.
As a fifteenth aspect, a perfluoropolyether in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and a more suitable linking group. About.

The perfluoropolyether constituting the curable composition of the present invention can be dissolved in various non-fluorinated organic solvents. Accordingly, the curable composition of the present invention is in the form of a varnish containing the perfluoropolyether, and a cured film having excellent transparency can be easily formed by applying the varnish to various substrate surfaces.
In addition, since the curable composition of the present invention has a surface modification effect derived from a perfluoroalkyl group, excellent film surface slipperiness and water repellency can be realized in a cured film obtained from the composition. Therefore, the present invention can provide an antifouling layer particularly useful for glass substrates. Furthermore, it is also possible to improve the durability of the antifouling layer by introducing a primer layer formed from a composition containing an alkoxysilane hydrolysis condensate between the base material and the antifouling layer.

[(A) Perfluoropolyether A]
In the curable composition of the present invention, an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and a suitable linking group. Perfluoropolyether A (hereinafter also simply referred to as “perfluoropolyether A”).

The number of carbon atoms of the alkylene group in the poly (oxyperfluoroalkylene) group is not particularly limited, but preferably 1 to 4 carbon atoms. That is, the poly (oxyperfluoroalkylene) group refers to a group having a structure in which a divalent fluorocarbon group having 1 to 4 carbon atoms and oxygen atoms are alternately connected, and the oxyperfluoroalkylene group is a carbon atom. This refers to a group having a structure in which a divalent fluorocarbon group of formulas 1 to 4 and an oxygen atom are linked. Specifically, — [OCF ₂ ] — (oxyperfluoromethylene group), — [OCF ₂ CF ₂ ] — (oxyperfluoroethylene group), — [OCF ₂ CF ₂ CF ₂ ] — (oxyperfluoropropane) -1,3-diyl group) and-[OCF ₂ C (CF ₃ ) F]-(oxyperfluoropropane-1,2-diyl group).
The above oxyperfluoroalkylene groups may be used alone or in combination of two or more. In such a case, the bonds of plural types of oxyperfluoroalkylene groups are block bonds and random bonds. Any of these may be used.

Among these, from the viewpoint of obtaining a cured film having good slipperiness, as the poly (oxyperfluoroalkylene) group, — [OCF ₂ ] — (oxyperfluoromethylene group) and — [OCF ₂ CF ₂ ] — It is preferable to use a group having both (oxyperfluoroethylene group) as a repeating unit.
Among them, as the poly (oxyperfluoroalkylene) group, the repeating unit: — [OCF ₂ ] — and — [OCF ₂ CF ₂ ] — are represented by a molar ratio of [Repeating unit: — [OCF ₂ ] —]: [Repeating Unit: — [OCF ₂ CF ₂ ] —] = 2: 1 to 1: 2 is preferable, and a group including about 1: 1 is more preferable. The bond of these repeating units may be either a block bond or a random bond.
The number of repeating units of the oxyperfluoroalkylene group is preferably in the range of 5 to 30, more preferably in the range of 7 to 21, as the total number of repeating units.
The weight average molecular weight (Mw) of the poly (oxyperfluoroalkylene) group measured in terms of polystyrene by gel permeation chromatography is 1,000 to 5,000, preferably 1,500 to 2,000. .

The number of carbon atoms of the alkylene group in the poly (oxyalkylene) group is not particularly limited, but preferably 1 to 5 carbon atoms. That is, the poly (oxyalkylene) group refers to a group having a structure in which an alkylene group having 1 to 5 carbon atoms and oxygen atoms are alternately connected, and the oxyalkylene group is a divalent alkylene having 1 to 5 carbon atoms. A group having a structure in which a group and an oxygen atom are linked.
The oxyalkylene groups may be used singly or in combination of two or more. In that case, the bonds of the plural oxyalkylene groups may be either block bonds or random bonds. May be.
Among these, the poly (oxyalkylene) group is preferably a poly (oxyethylene) group.
The number of repeating units of the oxyalkylene group in the poly (oxyalkylene) group is preferably in the range of 1 to 40, more preferably in the range of 2 to 20.

The alkoxysilyl group is preferably a group represented by the following formula [1].

In the above formula, R ¹ represents an alkyl group having 1 to 5 carbon atoms, R ² represents an alkyl group having 1 to 5 carbon atoms or a phenyl group, and a represents an integer of 1 to 3.

Examples of the linking group include alkylene groups having 1 to 5 carbon atoms, oxygen atoms, ester bonds, amide bonds, urethane bonds, urea bonds, and other divalent groups, and combinations thereof. .

Among these, the perfluoropolyether A of the present invention is preferably a compound represented by the following formula [2].

In the above formula, R ¹ and R ³ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ² and R ⁴ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. A and b each independently represent an integer of 1 to 3, L ^{1 to} L ⁴ each independently represents an alkylene group having 1 to 5 carbon atoms, and X ¹ and X ² each independently , —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein m and n are m + n from 2 to 40 PFPE1 represents a group having a poly (oxyperfluoroalkylene) structure as a core and a terminal structure linked to an oxyalkylene group on both sides thereof.

Specific examples of the alkyl group having 1 to 5 carbon atoms in R ¹ and R ³ include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group. Tert-butyl group, n-pentyl group, isoamyl group, neopentyl group, tert-amyl group, sec-isoamyl group, cyclopentyl group and the like.
Among these, as R ¹ and R ³ , a methyl group or an ethyl group is preferable.

Specific examples of the alkyl group having 1 to 5 carbon atoms in R ² and R ⁴ include the groups exemplified in the above R ¹ and R ³ .
R ² and R ⁴ are preferably a methyl group or a phenyl group.

The above a and b are preferably 3.

Specific examples of the alkylene group having 1 to 5 carbon atoms in L ^{1 to} L ⁴ include, for example, a methylene group, an ethylene group, a trimethylene group, a methylethylene group, a tetramethylene group, a 1-methyltrimethylene group, 2- Methyltrimethylene group, 1,1-dimethylethylene group, pentamethylene group, 1-methyltetramethylene group, 2-methyltetramethylene group, 1,1-dimethyltrimethylene group, 1,2-dimethyltrimethylene group, 2 , 2-dimethyltrimethylene group, 1-ethyltrimethylene group and the like.
Among these, as L ¹ and L ² , an ethylene group or a trimethylene group is preferable, and a trimethylene group is more preferable.
As also L ³ and L ^4, an ethylene group or a methylethylene group is preferred, more preferably an ethylene group. That is, the oxyalkylene group represented as (L ₃ O) or (OL ₄ ) is preferably an oxyethylene group.

X ¹ and X ² are preferably —OC (═O) — or —OC (═O) NH—, more preferably —OC (═O) NH—, and even more preferably * —. OC (= O) NH- (wherein * represents a bond end to (L ³ O) _m or (OL ⁴ ) _n ).

M and n are preferably 12 to 20.

PFPE1 represents a group having a poly (oxyperfluoroalkylene) structure as a core and a terminal structure linked to an oxyalkylene group on both sides thereof.
As the poly (oxyperfluoroalkylene) structure, the groups specifically mentioned above for the poly (oxyperfluoroalkylene) group can be mentioned as suitable structures.
The terminal structure linked to the oxyalkylene group present on both sides is, for example, **-CF ₂ CH _2- , **-when bonded to the -O-terminal of a poly (oxyperfluoroalkylene) group. When CF ₂ C (═O) — is bonded to the fluoroalkylene end of a poly (oxyperfluoroalkylene) group (—CF ₂ —, —C (CF ₃ ) F—, etc.), ** — O— CF ₂ CH ₂ —, ** — O—CF ₂ C (═O) — (** represents any bonding end with a poly (oxyperfluoroalkylene) group).

In the curable composition of the present invention, (a) perfluoropolyether A may be used alone or in combination of two or more.

The (a) perfluoropolyether A is, for example, a compound having a hydroxy group at both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group, On the other hand, for example, it can be obtained by a method of reacting an alkoxysilane having an isocyanate group such as (3-isocyanatopropyl) trimethoxysilane.
The alkoxysilyl group is bonded to both ends of the component (a), that is, the molecular chain containing the poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and further via a suitable linking group. Perfluoropolyethers are also the subject of the present invention.

[(B) Perfluoropolyether B]
In the curable composition of the present invention, (b) an alkoxysilyl group is bonded to both ends of the molecular chain containing a poly (oxyperfluoroalkylene) group via a linking structure having no poly (oxyalkylene) structure. The perfluoropolyether B may be contained.
Examples of the poly (oxyperfluoroalkylene) group and the alkoxysilyl group include the groups mentioned in the previous [(a) perfluoropolyether A]. In addition, examples of the linking structure having no poly (oxyalkylene) structure may include the groups listed as the “linking group” in the previous [(a) perfluoropolyether A].

Especially, it is preferable that the perfluoropolyether B which can be used by this invention is a compound represented by following formula [3].

In the above formula, R ⁵ and R ⁷ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ⁶ and R ⁸ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. R and s each independently represent an integer of 1 to 3, L ⁵ and L ⁶ each independently represent an alkylene group having 1 to 5 carbon atoms, and X ³ and X ⁴ each independently , —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein PFPE2 is poly (oxyperfluoroalkylene) A group having a terminal structure having the structure as a core and linking with X ³ or X ⁴ on both sides thereof is represented.

In the above formula, examples of the alkyl group having 1 to 5 carbon atoms in R ⁵ and R ⁷ and R ⁶ and R ⁸ include the alkyl groups exemplified in the aforementioned R ¹ and R ³ .
R ⁵ and R ⁷ are preferably a methyl group or an ethyl group.
R ⁶ and R ⁸ are preferably a methyl group or a phenyl group.
In addition, r and s are preferably 3.

Specific examples of the alkylene group having 1 to 5 carbon atoms in L ⁵ and L ⁶ include the alkylene groups exemplified in the aforementioned L ^{1 to} L ⁴ .
Among them, as L ⁵ and L ⁶ , an ethylene group or a trimethylene group is preferable, and a trimethylene group is more preferable.

X ³ and X ⁴ are preferably —OC (═O) — or —OC (═O) NH—, more preferably —OC (═O) NH—, and even more preferably * —. OC (= O) NH- (in the formula, * represents a bonding end with PFPE2).

PFPE2 represents a group having a poly (oxyperfluoroalkylene) structure as a core and a terminal structure linked to X ³ or X ⁴ on both sides thereof.
Examples of the poly (oxyperfluoroalkylene) structure and the terminal structure linked to X ³ and X ⁴ present on both sides thereof include the structures exemplified in the aforementioned PFPE1.

The above (b) perfluoropolyether B is, for example, a compound having a hydroxy group at both ends of a group containing a poly (oxyperfluoroalkylene) group. For example, (3-isocyanato It is obtained by a method of reacting an alkoxysilane having an isocyanate group such as propyl) trimethoxysilane.

In the curable composition of the present invention, (b) perfluoropolyether B may be used alone or in combination of two or more.
When the perfluoropolyether B is used, it is preferably used in an amount of 50% by mass or less based on the mass of the perfluoropolyether A described above, and the perfluoropolyether in an amount of 10 to 30% by mass. It is more preferable to use B. When the usage-amount of perfluoropolyether B exceeds 50 mass%, there exists a possibility that the solubility with respect to a solvent, especially a non-fluorine-type solvent may deteriorate.

[(C) Solvent]
The curable composition of the present invention may further contain (c) a solvent, that is, may be in the form of a varnish (film forming material).
As said solvent, the said (a) component or (a) and (b) component is melt | dissolved, and the workability | operativity at the time of the application concerning the cured film (hard-coat layer) formation mentioned later, the drying property before and behind hardening, etc. For example, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and tetralin; aliphatic or alicyclic hydrocarbons such as n-hexane, n-heptane, mineral spirit, and cyclohexane Halogens such as methyl chloride, methyl bromide, methyl iodide, dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, o-dichlorobenzene; ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate , Ethyl cellosolve acetate, propylene glycol monomethyl ether acetate Esters such as carbonates or ester ethers; diethyl ether, tetrahydrofuran, 1,4-dioxane, diethylene glycol diethyl ether, methyl cellosolve, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n -Ethers such as propyl ether, propylene glycol monoisopropyl ether, propylene glycol mono-n-butyl ether, diethylene glycol monoethyl ether, dipropylene glycol monomethyl ether; acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclopentanone Ketones such as cyclohexanone; methanol, ethanol, n-pro Nol, isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, cyclohexanol, 2-ethylhexyl alcohol, benzyl alcohol, ethylene glycol and other alcohols; N, N-dimethylformamide, N, N-dimethylacetamide, N -Amides such as methyl-2-pyrrolidone; Sulfoxides such as dimethyl sulfoxide, and a mixed solvent of two or more of these.
The amount of the solvent (c) used is not particularly limited, but for example, it is used at a concentration at which the solid content in the curable composition of the present invention is 0.001 to 80% by mass, preferably 0.01 to 70% by mass. . Here, the solid content concentration (also referred to as non-volatile content concentration) is based on the total mass (total mass) of the components (a) and (c) or the components (a) to (c) of the curable composition of the present invention. It represents the content of solid content (excluding solvent components from all components).

[Other additives]
In addition, additives that are generally added to the curable composition of the present invention as needed, for example, a leveling agent, a surfactant, an adhesion-imparting agent, and a plasticizer, unless the effects of the present invention are impaired. UV absorbers, antioxidants, storage stabilizers, antistatic agents, inorganic fillers, pigments, dyes and the like may be appropriately blended.

<Curing film>
The curable composition of the present invention can be coated (coated) on a substrate to form a coating film, and a cured film can be formed by heat-treating the coating film. The cured film is also an object of the present invention.
Examples of the base material in this case include various resins (polycarbonate, polymethacrylate, polystyrene, PET (polyethylene terephthalate), etc., polyolefin, polyamide, polyimide, epoxy resin, melamine resin, triacetyl cellulose, ABS (acrylonitrile- Butadiene-styrene copolymer), AS (acrylonitrile-styrene copolymer), norbornene resin, etc.), metals, inorganic oxides, wood, paper, glass, slate and the like. The shape of these base materials may be a plate shape, a film shape, or a three-dimensional molded body.

The coating method on the base material is a cast coating method, a spin coating method, a blade coating method, a dip coating method, a roll coating method, a spray coating method, a bar coating method, a die coating method, an ink jet method, a printing method (a relief plate, an intaglio plate). Lithographic printing, screen printing, etc.) can be selected as appropriate.
In particular, since it can be applied in a short time, even a highly volatile solution can be used, and it is desirable to use a spin coating method from the advantage that uniform application can be easily performed. In addition, a roll coating method, a die coating method, or a spray coating method may be selected from the advantages that it can be easily applied and a smooth coating film can be formed without coating unevenness in a large area. The curable composition used here can be suitably used in the form of the aforementioned varnish.
In addition, it is preferable to use for a coating after filtering a curable composition beforehand using the filter etc. with a hole diameter of about 0.2 micrometer in the case of application | coating on a base material. Moreover, when apply | coating, it is good also as a form of a varnish by adding a solvent to this curable composition as needed. Examples of the solvent in this case include various solvents mentioned in the above-mentioned [(c) Solvent].

After the curable composition is applied on the substrate to form a coating film, heat treatment is performed to form a cured film.
The heat treatment method is not particularly limited, and for example, it can be carried out using a hot plate or an oven in an appropriate atmosphere, that is, in an inert gas such as air or nitrogen, in a vacuum, or the like. The conditions for the heat treatment are not particularly limited as long as the solvent can be evaporated and the polymerization and polycondensation can be completed (when the solvent is contained in the curable composition). For example, the treatment temperature is 40 to 250 ° C. The treatment time can be appropriately selected from 5 minutes to 24 hours. In addition, for the purpose of removing (drying) the solvent that can be contained in the coating film, the temperature change in two or more steps is performed for the purpose of developing a higher uniform film forming property or causing the reaction to proceed on the substrate. May be attached.
The thickness of the cured film thus formed is usually 0.001 to 50 μm, preferably 0.001 to 20 μm after drying and curing.

<Anti-fouling substrate>
Using the curable composition of the present invention, an antifouling group comprising an antifouling layer on at least one surface of an inorganic oxide substrate or a metal substrate, or comprising a primer layer and an antifouling layer in this order. The material can be manufactured. The antifouling substrate is also an object of the present invention. The antifouling layer in the antifouling substrate serves as a layer for protecting the surface of various display elements such as a touch panel and a liquid crystal display.

The antifouling substrate of the present invention has the following form (i) or (ii).
(I) An antifouling substrate comprising an antifouling layer on at least one surface of an inorganic oxide substrate or a metal substrate:
The antifouling layer is formed on the substrate by applying the above-described curable composition onto an inorganic oxide substrate or a metal substrate to form a coating film, and heating and curing the coating film. It becomes.
(Ii) Antifouling substrate comprising a primer layer and an antifouling layer in this order on at least one surface of an inorganic oxide substrate or a metal substrate:
The primer layer includes a step of coating a composition containing all or a partial hydrolysis-condensation product of tetraalkoxysilane on an inorganic oxide substrate or a metal substrate to form a coating film, and a step of heating and curing the coating film. Is formed on the substrate; the antifouling is applied on the primer layer by applying the curable composition described above on the primer layer to form a coating film, and heating and curing the coating film. A layer is formed.

Examples of the inorganic oxide substrate used in the antifouling substrate of the present invention include a substrate containing at least one inorganic oxide selected from silica, titanium oxide, alumina oxide, and zirconia oxide.
Examples of the metal substrate include substrates containing at least one metal such as gold, silver, and copper.

When the antifouling substrate of the present invention contains a primer layer, the composition used for forming the primer layer contains all or a partial hydrolysis condensate of tetraalkoxysilane (hereinafter also referred to as an adhesion primer). .
The whole or partial hydrolysis-condensation product (also referred to as siloxane oligomer) of the tetraalkoxysilane is obtained by a conventionally known method. For example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane or tetra It is obtained by hydrolyzing and condensing a tetraalkoxysilane such as -n-butoxysilane in an organic solvent. In addition to tetraalkoxysilane, other alkoxysilanes such as trimethoxy (methyl) silane, triethoxy (methyl) silane, ethyltrimethoxysilane, triethoxy (ethyl) silane, trimethoxy (propyl) silane, triethoxy (propyl) Silane, trimethoxy (3,3,3-trifluoropropyl) silane, triethoxy (3,3,3-trifluoropropyl) silane, butyltrimethoxysilane, butyltriethoxysilane, trimethoxy (pentyl) silane, triethoxy (pentyl) Trialkoxysilanes such as silane, hexyltrimethoxysilane, triethoxy (hexyl) silane, trimethoxy (phenyl) silane, triethoxy (phenyl) silane; dimethoxydimethylsilane, die Xydimethylsilane, diethyldimethoxysilane, diethoxydiethylsilane, dimethoxydipropylsilane, diethoxydipropylsilane, dibutyldimethoxysilane, dibutyldiethoxysilane, dimethoxydipentylsilane, diethoxydipentylsilane, dihexyldimethoxysilane, diethoxydihexylsilane Dialkoxysilanes such as dimethoxydiphenylsilane or diethoxydiphenylsilane; alkoxysilanes including monoalkoxysilanes such as methoxytrimethylsilane, ethoxytrimethylsilane, triethyl (methoxy) silane or ethoxytriethylsilane.

Specific examples of the polycondensation of the alkoxysilane include a method of hydrolyzing and condensing the alkoxysilane in a solvent such as alcohol or glycol. At that time, the hydrolysis / condensation reaction may be either partial hydrolysis or complete hydrolysis. In the case of complete hydrolysis, theoretically, 0.5 times mole of water of all alkoxy groups in the alkoxysilane may be added, but it is usually preferable to add an excess amount of water more than 0.5 times mole. The amount is preferably 0.5 to 2.5 moles of all alkoxy groups in the alkoxysilane.
Usually, for the purpose of promoting hydrolysis / condensation reaction, formic acid, acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, 2-ethylhexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, stearin Acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, oxalic acid, malonic acid, methylmalonic acid, succinic acid, tartaric acid, maleic acid, fumaric acid, adipic acid, sebacic acid, citric acid, monochloroacetic acid, dichloroacetic acid, Organic acids such as trichloroacetic acid, trifluoroacetic acid, benzoic acid, p-aminobenzoic acid, salicylic acid, gallic acid, phthalic acid, mellitic acid, benzenesulfonic acid, p-toluenesulfonic acid; hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, Inorganic acids such as phosphoric acid and metal salts thereof; ammonia, methylamine, ethylamine, ethanolamine, triethylamine Catalysts such as alkali emissions and the like are used. In addition, it is also common to further promote the hydrolysis / condensation reaction by heating the solution in which the alkoxysilane is dissolved. At that time, the heating temperature and the heating time can be appropriately selected as desired. For example, a method of heating / stirring at 50 ° C. for 24 hours, a method of heating / stirring under reflux for 1 hour and the like can be mentioned.
As another method, for example, a method of heating and polycondensing a mixture of alkoxysilane, a solvent and oxalic acid can be mentioned. Specifically, after adding oxalic acid to alcohol in advance to make an alcohol solution of oxalic acid, the alkoxysilane is mixed while the solution is heated. In that case, the amount of oxalic acid used is preferably 0.2 to 2 mol with respect to 1 mol of all alkoxy groups of the alkoxysilane. Heating in this method can be performed at a liquid temperature of 50 to 180 ° C. A method of heating for several tens of minutes to several tens of hours under reflux is preferred so that the liquid does not evaporate or volatilize.

The weight average molecular weight (Mw) measured in terms of polystyrene by gel permeation chromatography of the total or partial hydrolysis-condensation product (siloxane oligomer) of tetraalkoxysilane thus obtained is 100 to 10,000, preferably 500 to 5 , 000.
Moreover, the obtained reaction solution containing the siloxane oligomer can be used as an adhesive primer as it is. Moreover, you may add a solvent and surfactant to an adhesion primer as needed.
As said solvent, the solvent illustrated to the above-mentioned [(c) solvent] can be used.

The method described in the above <cured film> is used for the method of applying the adhesion primer (coating film forming step) and the heat treatment method (curing step) of the coating film on the inorganic oxide substrate or metal substrate. Can do. The film thickness of the primer layer thus obtained is preferably 1 to 200 nm, more preferably 10 to 100 nm.

Moreover, the coating method (coating process) of the curable composition on the inorganic oxide substrate or metal substrate or the primer layer (coating process) and the heat treatment method (curing process) of the coating are the above-described <curing The methods listed in <Film> can be used. The film thickness of the antifouling layer thus obtained is preferably 1 to 50 nm, more preferably 1 to 40 nm.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not limited to the following Example.
In the examples, the apparatus and conditions used for sample preparation and physical property analysis are as follows.

(1) Gel permeation chromatography (GPC)
Equipment: HLC-8220GPC manufactured by Tosoh Corporation
Column: Shodex (registered trademark) GPC KF-804L, GPC KF-805L manufactured by Showa Denko K.K.
Column temperature: 40 ° C
Eluent: Tetrahydrofuran Detector: RI
(2) Spin coater: MS-A100 manufactured by Mikasa Co., Ltd.
(3) Hot plate equipment: MH-180CS, MH-3CS manufactured by AS ONE Corporation
(4) dynamic friction coefficient mu _k measuring apparatus: manufactured by Shinto Scientific Co. load variation type friction and wear test system TRIBOGEAR (TM) TYPE: HHS2000
Probe: 0.6mmR Sapphire pin Load: 50g
Scanning speed: 1 mm / second Scanning distance: 10 mm
(5) Contact angle measurement device: DropMaster DM-501, manufactured by Kyowa Interface Science Co., Ltd.
Measurement temperature: 20 ° C
(6) Durability test Equipment: Reciprocating wear tester manufactured by Shinto Kagaku Co., Ltd. TRIBOGEAR (registered trademark) TYPE: 30S
Scanning speed: 1040 mm / min Scanning distance: 40 mm

Abbreviations represent the following meanings.
EO-PFPE: Perfluoropolyether having a poly (oxyalkylene) group and a hydroxy group at both ends [Fluorolink (registered trademark) 5147X manufactured by Solvay Specialty Polymers Japan Co., Ltd.]
DO-PFPE: Perfluoropolyether having hydroxyl groups at both ends [Fomlin (registered trademark) D4000, manufactured by Solvay Specialty Polymers Japan Ltd.]
IPTMS: (3-isocyanatopropyl) trimethoxysilane [SILQUEST (registered trademark) A-LINK35 manufactured by Momentive Performance Materials Japan (same)]
S10: Perfluoropolyether having silyl groups via urethane bonds at both ends [Fluorolink (registered trademark) S10, manufactured by Solvay Specialty Polymers Japan Co., Ltd.]
TEOS: Tetraethoxysilane [Momentive Performance Materials Japan (same) TSL8124]
CHN: cyclohexanone CPN: cyclopentanone DO: 1,4-dioxane IPA: 2-propanol MEK: methyl ethyl ketone NMP: N-methyl-2-pyrrolidone

[Example 1] Production of antifouling material 1 (AF1) A brown screw tube was charged with 1.05 g (0.5 mmol) of EO-PFPE and 0.82 g (4 mmol) of IPTMS. This mixture was stirred for 24 hours at room temperature (approximately 25 ° C.) using a stirrer chip, and 56 masses of S-EO-PFPE corresponding to silyl-terminated perfluoropolyether A (PFPE-A) having an oxyalkylene group. % Antifouling material 1 (AF1) was obtained.
The solvent solubility of the obtained antifouling material was evaluated. In the evaluation, AF1 and the solvent described in Table 1 were mixed so that the silyl-terminated perfluoropolyether concentration was 1% by mass, stirred at room temperature (approximately 25 ° C.) for 5 minutes, and the state after standing for 5 minutes. Visual confirmation was made and the following criteria were followed. The results are also shown in Table 1.
[Solvent solubility]
A: uniformly dissolved B: cloudy and not uniform solution C: phase separated and not dissolved or dispersed

[Example 2] Production of antifouling material 2 (AF2) A brown screw tube was charged with 0.84 g (0.4 mmol) of EO-PFPE, 0.40 g (0.1 mmol) of DO-PFPE and 0.82 g (4 mmol) of IPTMS. . This mixture was stirred for 24 hours at room temperature (approximately 25 ° C.) using a stirrer chip, and S-EO-PFPE corresponding to PFPE-A and silyl-terminated perfluoropolyether B having no oxyalkylene group ( An antifouling material 2 (AF2) containing 60% by mass of a mixture (molar ratio 80:20) with S-PFPE corresponding to PFPE-B) was obtained.
The solvent solubility of the obtained antifouling material was evaluated in the same manner as in Example 1. The results are also shown in Table 1.

[Example 3] Production of antifouling material 3 (AF3) A brown screw tube was charged with 0.74 g (0.35 mmol) of EO-PFPE, 0.60 g (0.15 mmol) of DO-PFPE and 0.82 g (4 mmol) of IPTMS. . This mixture was stirred for 24 hours at room temperature (approximately 25 ° C.) using a stirrer chip, and a mixture (molar ratio) of S-EO-PFPE corresponding to PFPE-A and S-PFPE corresponding to PFPE-B. Antifouling material 3 (AF3) containing 62 mass% of 70:30) was obtained.
The solvent solubility of the obtained antifouling material was evaluated in the same manner as in Example 1. The results are also shown in Table 1.

Comparative Example 1 Solvent solubility of silyl-terminated perfluoropolyether having no oxyalkylene group The solvent solubility of S10 corresponding to PFPE-B was evaluated in the same manner as in Example 1. The results are also shown in Table 1.

As shown in Table 1, the antifouling material 1 (AF1) to the antifouling material 3 (AF3) of Examples 1 to 3 are all uniform with respect to various non-fluorinated solvents including MEK. Dissolved.
On the other hand, in Comparative Example 1 consisting of only the silyl-terminated perfluoropolyether B having no oxyalkylene group, the phase separation with most non-fluorinated solvents resulted in poor solubility.

[Production Example 1] Production of adhesion primer (PR) In a 200 mL four-necked flask, 20.8 g (100 mmol) of TEOS and 13.6 g of ethanol were charged and stirred at room temperature (approximately 25 ° C) for 10 minutes. A separately prepared mixed solution of oxalic anhydride (manufactured by Kanto Chemical Co., Inc.) 0.11 g (1.2 mmol), water 6.3 g and ethanol 13.6 g was added dropwise over 30 minutes. The solution was stirred for 10 minutes, then heated until the internal liquid was refluxed (approximately 80 ° C.) and stirred for 1 hour. The reaction mixture was cooled to 30 ° C. to obtain an adhesion primer (PR) containing 38% by mass of a siloxane oligomer.
The obtained siloxane oligomer had a weight average molecular weight Mw measured in terms of polystyrene by GPC of 1,200, and a degree of dispersion: Mw (weight average molecular weight) / Mn (number average molecular weight) was 1.1.

[Example 4] Antifouling layer using AF1 0.02 g of AF1 obtained in Example 1 was dissolved in 11.18 g of MEK to prepare a varnish having a perfluoropolyether component concentration of 0.1% by mass. This varnish was spin-coated (slope 5 seconds, 2000 rpm x 30 seconds) on a 100 x 100 x 1.1 mm thin glass sheet for chemical strengthening [Dragonrail (registered trademark) manufactured by AGC Fabricec Co., Ltd.] that had been ultrasonically cleaned with IPA in advance. , Slope 5 seconds) to obtain a coating film. This coating film was dried on an 80 ° C. hot plate for 3 minutes, and further heated and cured on a 150 ° C. hot plate for 30 minutes to obtain an antifouling layer having a thickness of about 10 nm.
The obtained antifouling layer was evaluated for transparency, slipperiness, water repellency and durability. The procedure for each evaluation is shown below. The results are also shown in Table 2.

[transparency]
The antifouling layer was visually confirmed and evaluated according to the following criteria.
A: Transparent with no coating unevenness B: Partially cloudy with coating unevenness C: The entire antifouling layer is cloudy

[Slippery]
The dynamic friction coefficient mu _k 5 points antifouling layer surface was measured, and evaluated based on the following from the average value. Note that the smaller the value of the dynamic friction coefficient value, the smaller the friction with the probe in use, which is a measure of slipperiness.
A: μ _k <0.06
B: 0.06 ≦ μ _k <0.08
C: μ _k ≧ 0.08

[Water repellency]
1 μL of water was allowed to adhere to the surface of the antifouling layer, the contact angle θ after 10 seconds was measured 5 times, and the average value was evaluated according to the following criteria.
A: θ ≧ 100 °
B: 90 ° ≦ θ <100 °
C: θ <90 °

[durability]
The antifouling layer surface was rubbed 1000 reciprocally by applying a load of 1 kg with a cylindrical eraser [RUBBER STICK manufactured by Minoan, φ6.0 mm] attached to a reciprocating wear tester. 1 μL of water was adhered to the rubbed portion, and the contact angle θ after 5 seconds was measured 5 times, and the average value was evaluated according to the following criteria.
A: θ ≧ 90 °
B: 50 ° ≦ θ <90 °
C: θ <50 °

[Example 5] Antifouling layer using AF2 0.02 g of AF2 obtained in Example 2 was dissolved in 11.98 g of CPN to prepare a varnish having a perfluoropolyether component concentration of 0.1% by mass. An antifouling layer having a thickness of about 10 nm was prepared and evaluated in the same manner as in Example 4 except that this varnish was used. The results are also shown in Table 2.

[Example 6] Antifouling layer using AF3 0.02 g of AF3 obtained in Example 3 was dissolved in 12.38 g of MEK to prepare a varnish having a perfluoropolyether component concentration of 0.1% by mass. An antifouling layer having a thickness of about 10 nm was prepared and evaluated in the same manner as in Example 4 except that this varnish was used. The results are also shown in Table 2.

[Example 7] Antifouling layer using AF2 through primer layer PR 1.0 g obtained in Production Example 1 was dissolved in 37 g of an ethanol / water mixed solution (mass ratio 9/1), and the concentration of the siloxane oligomer was A 1% by weight varnish was prepared. This varnish was spin-coated (slope 5 seconds, 2000 rpm x 30 seconds) on a 100 x 100 x 1.1 mm thin glass sheet for chemical strengthening [Dragonrail (registered trademark) manufactured by AGC Fabricec Co., Ltd.] that had been ultrasonically cleaned with IPA in advance. , Slope 5 seconds) to obtain a coating film. This coating film was dried on a hot plate at 80 ° C. for 3 minutes, and further heated and cured on a hot plate at 150 ° C. for 30 minutes to form a primer layer having a thickness of about 40 nm.
On this primer layer, an antifouling layer having a thickness of about 10 nm was prepared and evaluated in the same manner as in Example 5. The results are also shown in Table 2.

[Comparative Example 2] Antifouling layer using silyl-terminated perfluoropolyether having no oxyalkylene group 0.01 g of S10 was dissolved in 9.99 g of IPA, and the concentration of the perfluoropolyether component was 0.1% by mass. A varnish was prepared. An antifouling layer having a thickness of about 10 nm was prepared and evaluated in the same manner as in Example 4 except that this varnish was used. The results are also shown in Table 2.

As shown in Table 2, the antifouling layers of Examples 4 to 7 using the antifouling material 1 (AF1) to the antifouling material 3 (AF3) are all excellent in transparency, slipperiness, and water repellency. It became the result. In particular, in Example 7 in which the primer layer was introduced between the base material and the antifouling layer, a result that the durability of the antifouling layer was greatly improved was obtained.
On the other hand, the antifouling layer of Comparative Example 1 using a silyl-terminated perfluoropolyether having no oxyalkylene group is water-repellent, but is inferior in transparency, slipperiness and durability of the antifouling layer. As a result.

Claims (15)

1. (A) Perfluoropolyether A in which an alkoxysilyl group is bonded to each end of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and further via a suitable linking group. A curable composition comprising.
2. The curable composition according to claim 1, wherein the poly (oxyalkylene) group is a poly (oxyethylene) group.
3. The curable composition according to claim 1, wherein the poly (oxyperfluoroalkylene) group is a group having — [OCF ₂ ] — and — [OCF ₂ CF ₂ ] — as repeating units.
4. The curable composition according to any one of claims 1 to 3, wherein the alkoxysilyl group is a group represented by the formula [1].
   

   

   (Wherein R ¹ represents an alkyl group having 1 to 5 carbon atoms, R ² represents an alkyl group having 1 to 5 carbon atoms or a phenyl group, and a represents an integer of 1 to 3)
5. The curable composition according to claim 4, wherein the perfluoropolyether A is a compound represented by the formula [2].
   

   

   (In the formula, R ¹ and R ³ each independently represents an alkyl group having 1 to 5 carbon atoms, and R ² and R ⁴ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. , A and b each independently represent an integer of 1 to 3, L ^{1 to} L ⁴ each independently represents an alkylene group having 1 to 5 carbon atoms, and X ¹ and X ² each independently represent: —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein m and n are 2 to 40 PFPE1 represents a group having a poly (oxyperfluoroalkylene) structure as a core and a terminal structure linked to an oxyalkylene group on both sides thereof.
6. Further, (b) perfluoropolyether B in which an alkoxysilyl group is bonded to each end of a molecular chain containing a poly (oxyperfluoroalkylene) group via a linking structure having no poly (oxyalkylene) structure. The curable composition as described in any one of Claims 1 thru | or 5 containing.
7. The curable composition according to claim 6, wherein the perfluoropolyether B is a compound represented by the formula [3].
   

   

   (In the formula, R ⁵ and R ⁷ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ⁶ and R ⁸ each independently represent an alkyl group having 1 to 5 carbon atoms or a phenyl group. , R and s each independently represent an integer of 1 to 3, L ⁵ and L ⁶ each independently represent an alkylene group having 1 to 5 carbon atoms, and X ³ and X ⁴ each independently represent: —OC (═O) —, —OC (═O) NH—, —NHC (═O) —, —NHC (═O) NH— or —O—, wherein PFPE2 is a poly (oxyperfluoroalkylene) structure Represents a group having a terminal structure linked to X ³ or X ⁴ on the both sides thereof.)
8. The curable composition according to claim 6 or 7, wherein a content of the perfluoropolyether B is 50% by mass or less of the perfluoropolyether A.
9. Furthermore, (c) The curable composition as described in any one of Claims 1 thru | or 8 containing a solvent.
10. The cured film obtained from the curable composition as described in any one of Claims 1 thru | or 9.
11. An antifouling substrate comprising an antifouling layer on at least one surface of an inorganic oxide substrate or a metal substrate, wherein the antifouling layer is formed on the inorganic oxide substrate or the metal substrate An antifouling substrate formed by heating and curing a coating film comprising the curable composition according to any one of claims 1 to 9.
12. An antifouling substrate comprising a primer layer and an antifouling layer in this order on at least one surface of an inorganic oxide substrate or a metal substrate, wherein the primer layer is the inorganic oxide substrate or metal substrate The antifouling layer is formed on the primer layer, wherein the antifouling layer is formed on the primer layer by heating and curing a coating film comprising all or a partial hydrolysis-condensation product of tetraalkoxysilane formed thereon. The antifouling substrate formed by heating and hardening the coating film of the curable composition as described in any one of Claims 9.
13. The antifouling substrate according to claim 12, wherein the primer layer has a thickness of 1 to 200 nm.
14. The antifouling substrate according to any one of claims 11 to 13, wherein the antifouling layer has a thickness of 1 to 50 nm.
15. A perfluoropolyether in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group via a poly (oxyalkylene) group and further via a suitable linking group.