阅读说明：本技术 带拒水拒油层的物品及其制造方法 (Article with water-and oil-repellent layer and method for producing the same ) 是由 周莅霖 诹访久美子 石关健二 平社英之 小林大介 末原道教 德永未央 于 2018-06-18 设计创作，主要内容包括：本发明提供拒水拒油层的耐磨耗性优异的带拒水拒油层的物品及其制造方法。一种带拒水拒油层的物品(10),其具有：基材(12)；由具有水解性甲硅烷基的含氟化合物的水解缩合物形成的拒水拒油层(16)；和,在基材(12)与拒水拒油层(16)之间存在的、含有碱金属原子的硅氧化物层(14),该硅氧化物层(14)中,自与拒水拒油层(16)接触的面起的深度为0.1nm以上且0.3nm以下的区域的碱金属原子的浓度的平均值为2.0×10<Sup>19</Sup>atoms/cm<Sup>3</Sup>以上。(The invention provides an article with a water-repellent and oil-repellent layer having excellent abrasion resistance and a method for producing the same. Article (1) with water-repellent and oil-repellent layer0) The water-repellent oil-repellent paint comprises a substrate (12), a water-repellent oil-repellent layer (16) formed from a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group, and a silicon oxide layer (14) containing an alkali metal atom and existing between the substrate (12) and the water-repellent oil-repellent layer (16), wherein the average value of the concentration of the alkali metal atom in a region having a depth of 0.1nm to 0.3nm from the surface of the silicon oxide layer (14) in contact with the water-repellent oil-repellent layer (16) is 2.0 × 10 19 atoms/cm 3 The above.)

1. An article having a water-and oil-repellent layer, comprising:

a substrate;

a water-and oil-repellent layer formed from a hydrolysis condensate of a fluorine-containing compound having a hydrolyzable silyl group; and

a silicon oxide layer containing an alkali metal atom and present between the substrate and the water-and oil-repellent layer,

the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group and a hydrolyzable silyl group, a fluorine-containing compound having a group containing an etheric oxygen atom between carbon atoms of the fluoroalkyl group and a hydrolyzable silyl group, or a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain,

in the silicon oxide layer, the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

2. The article according to claim 1, wherein the number of hydrolyzable silyl groups of the fluorine-containing compound having a hydrolyzable silyl group is 2 or more.

3. The article according to claim 1 or 2, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain containing an oxyfluoroalkylene group having a carbon number of 1 to 10.

4. The article of claim 3, wherein the poly (oxyfluoroalkylene) chain comprises an oxyperfluoroalkylene group having a carbon number of 1 to 10.

5. The article according to any one of claims 1 to 3, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing ether compound represented by the following formula X,

[A¹-O-(R^f1O)_m1]_a-Q-[SiR¹³ _n1X¹ _3-n1]_b···X

wherein A is¹Is C1-20 perfluoroalkyl, R^f1Is a C1-10 fluoroalkylene group, m1 is an integer of 2-210, (R)^f1O)_m1Optionally contains more than 2 kinds of R with different carbon numbers^f1O, a and b are each independently an integer of 1 or more, Q is a linking group having a + b valences, R¹³Is a hydrogen atom or a 1-valent hydrocarbon group, X¹N1 is an integer of 0 to 2, 3 [ SiR ] s¹³ _n1X¹ _3-n1]Optionally not all are the same group.

6. The article according to any one of claims 1 to 5, wherein the concentration of the alkali metal atoms has an average value of 4.0 × 10²²atoms/cm³The following.

7. The article according to any one of claims 1 to 6, wherein at least a part of the alkali metal atoms are sodium atoms.

8. The article according to any one of claims 1 to 7, wherein the silicon oxide in the silicon oxide layer comprises a condensate of silicic acid or a hydrolytic condensate of alkoxysilane.

9. The article according to any one of claims 1 to 8, wherein the silicon oxide in the silicon oxide layer comprises an evaporation of a silicon oxide containing an alkali metal atom.

10. A process for producing an article having a water-and oil-repellent layer, characterized by forming a silicon oxide layer containing an alkali metal atom on the surface of a substrate using a silicon oxide-forming material comprising a silicon oxide precursor and an alkali metal source,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer,

the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group and a hydrolyzable silyl group, a fluorine-containing compound having a group containing an etheric oxygen atom between carbon atoms of the fluoroalkyl group and a hydrolyzable silyl group, or a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain,

in the method, the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

11. The production method according to claim 10, wherein the number of hydrolyzable silyl groups of the fluorine-containing compound having a hydrolyzable silyl group is 2 or more.

12. The production method according to claim 10 or 11, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain containing an oxyfluoroalkylene group having a carbon number of 1 to 10.

13. The production process according to claim 12, wherein the poly (oxyfluoroalkylene) chain comprises an oxyperfluoroalkylene group having a carbon number of 1 to 10.

14. The production method according to any one of claims 10 to 12, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing ether compound represented by the following formula X,

[A¹-O-(R^f1O)_m1]_a-Q-[SiR¹³ _n1X¹ _3-n1]_b···X

wherein A is¹Is C1-20 perfluoroalkyl, R^f1Is a C1-10 fluoroalkylene group, m1 is an integer of 2-210, (R)^f1O)_m1Optionally contains more than 2 kinds of R with different carbon numbers^f1O, a and b are each independently an integer of 1 or more, Q is a linking group having a + b valences, R¹³Is a hydrogen atom or a 1-valent hydrocarbon group, X¹N1 is an integer of 0 to 2, 3 [ SiR ] s¹³ _n1X¹ _3-n1]Optionally not all are the same group.

15. The production method according to any one of claims 10 to 14, wherein the silicon oxide layer is formed on the surface of the base material using a coating liquid containing at least 1 silicon oxide precursor selected from the group consisting of silicic acid, a partial condensate of silicic acid, tetraalkoxysilane, and a partial condensate thereof, and an alkali metal source and a solvent.

16. A process for producing an article having a water-and oil-repellent layer, characterized in that a silicon oxide layer containing an alkali metal atom is formed on the surface of a substrate using a silicon oxide containing an alkali metal atom,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer,

the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group and a hydrolyzable silyl group, a fluorine-containing compound having a group containing an etheric oxygen atom between carbon atoms of the fluoroalkyl group and a hydrolyzable silyl group, or a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain,

in the method, the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

17. The production method according to claim 16, wherein the number of hydrolyzable silyl groups of the fluorine-containing compound having a hydrolyzable silyl group is 2 or more.

18. The production method according to claim 16 or 17, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain containing an oxyfluoroalkylene group having a carbon number of 1 to 10.

19. The production process according to claim 18, wherein the poly (oxyfluoroalkylene) chain comprises an oxyperfluoroalkylene group having a carbon number of 1 to 10.

20. The production method according to any one of claims 16 to 18, wherein the fluorine-containing compound having a hydrolyzable silyl group is a fluorine-containing ether compound represented by the following formula X,

[A¹-O-(R^f1O)_m1]_a-Q-[SiR¹³ _n1X¹ _3-n1]_b···X

wherein A is¹Is C1-20 perfluoroalkyl, R^f1Is a C1-10 fluoroalkylene group, m1 is an integer of 2-210, (R)^f1O)_m1Optionally contains more than 2 kinds of R with different carbon numbers^f1O, a and b are each independently an integer of 1 or more, Q is a linking group having a + b valences, R¹³Is a hydrogen atom or a 1-valent hydrocarbon group, X¹N1 is an integer of 0 to 2, 3 [ SiR ] s¹³ _n1X¹ _3-n1]Optionally not all are the same group.

21. The production method according to any one of claims 16 to 20, wherein a content of the alkali metal atom in the silicon oxide containing the alkali metal atom is 200ppm or more with respect to a silicon atom.

22. The production method according to any one of claims 16 to 21, wherein a method for forming the silicon oxide layer is an evaporation method.

23. The production method according to any one of claims 10 to 22, wherein the average concentration of alkali metal atoms in the region is 4.0 × 10²²atoms/cm³The following.

24. The production method according to any one of claims 10 to 23, wherein at least a part of the alkali metal atoms are sodium atoms.

25. The production method according to any one of claims 10 to 24, wherein the surface of the substrate is subjected to corona discharge treatment, plasma treatment or plasma graft polymerization treatment, and then the silicon oxide layer is formed on the treated surface of the substrate.

26. A process for producing an article having a water-and oil-repellent layer, characterized by forming a silicon oxide layer containing an alkali metal atom on the surface of a substrate using a silicon oxide-forming material comprising a silicon oxide precursor and an alkali metal source,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer, and then heating, humidification or light irradiation is performed,

in the method, the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

27. The production method according to claim 26, wherein the silicon oxide layer is formed on the substrate surface using a coating liquid containing at least 1 silicon oxide precursor selected from the group consisting of silicic acid, a partial condensate of silicic acid, tetraalkoxysilane, and a partial condensate thereof, and an alkali metal source and a solvent.

28. A process for producing an article having a water-and oil-repellent layer, characterized in that a silicon oxide layer containing an alkali metal atom is formed on the surface of a substrate using a silicon oxide containing an alkali metal atom,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer, and then heating, humidification or light irradiation is performed,

in the method, the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

29. The production method according to claim 28, wherein a content of the alkali metal atom in the silicon oxide containing the alkali metal atom is 200ppm or more with respect to a silicon atom.

30. The manufacturing method according to claim 28 or 29, wherein a method of forming the silicon oxide layer is an evaporation method.

31. The production method according to any one of claims 26 to 30, wherein the average concentration of alkali metal atoms in the region is 4.0 × 10²²atoms/cm³The following.

32. The production method according to any one of claims 26 to 31, wherein at least a part of the alkali metal atoms are sodium atoms.

33. The production method according to any one of claims 26 to 32, wherein the surface of the substrate is subjected to corona discharge treatment, plasma treatment or plasma graft polymerization treatment, and then the silicon oxide layer is formed on the treated surface of the substrate.

34. A process for producing an article having a water-and oil-repellent layer, characterized in that a silicon oxide layer containing an alkali metal atom is formed on the surface of a substrate by a vacuum deposition method using a silicon oxide containing an alkali metal atom,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer,

in the method, the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

35. The production method according to claim 34, wherein a content of the alkali metal atom in the silicon oxide containing the alkali metal atom is 200ppm or more with respect to a silicon atom.

36. The production method according to claim 34 or 35, wherein the average of the concentrations of alkali metal atoms in the region is 4.0 × 10²²atoms/cm³The following.

37. The production method according to any one of claims 34 to 36, wherein at least a part of the alkali metal atoms are sodium atoms.

38. The production method according to any one of claims 34 to 37, wherein the surface of the substrate is subjected to corona discharge treatment, plasma treatment, or plasma graft polymerization treatment, and then the silicon oxide layer is formed on the treated surface of the substrate.

Technical Field

The present invention relates to an article having a water-and oil-repellent layer and a method for producing the same.

Background

In order to impart water-and oil-repellency, fingerprint stain removability, lubricity (smoothness when touched with a finger), and the like to the surface of a substrate, it is known that a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound is formed on the surface of the substrate by surface treatment using a fluorine-containing compound having a poly (oxyperfluoroalkylene) chain and a hydrolyzable silyl group.

Further, since the water-and oil-repellent layer is required to have abrasion resistance, an undercoat layer is provided between the substrate and the water-and oil-repellent layer in order to improve adhesion between the substrate and the water-and oil-repellent layer. For example, a water-and oil-repellent layer is provided between the substrate and the water-and oil-repellent layer by vapor depositionA silicon oxide layer (patent documents 1 and 2) comprising Si (NCO) provided between a substrate and a water-and oil-repellent layer₄And the like (patent document 3).

Disclosure of Invention

Problems to be solved by the invention

In the silicon oxide layer and the underlayer described in patent documents 1 to 3, the adhesiveness between the base material and the water-and oil-repellent layer may be insufficient. Further improvement in abrasion resistance is required for the water-and oil-repellent layer, and for this reason, further improvement in adhesion between the substrate and the water-and oil-repellent layer is also required.

The object of the present invention is to provide a water-and oil-repellent layer-bearing article having excellent abrasion resistance of the water-and oil-repellent layer, and a method for producing the same.

Means for solving the problems

The present invention provides an article with a water-and oil-repellent layer having the following configurations [1] to [17], and a method for producing the same.

[1] An article having a water-and oil-repellent layer, comprising: a substrate; a water-and oil-repellent layer formed from a hydrolysis condensate of a fluorine-containing compound having a hydrolyzable silyl group; and a silicon oxide layer containing an alkali metal atom and present between the substrate and the water-and oil-repellent layer,

in the silicon oxide layer, the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

[2]According to [1]The article according to (1), wherein the average concentration of the alkali metal atoms is 4.0 × 10²²atoms/cm³The following.

[3] The article according to [1] or [2], wherein at least a part of the alkali metal atoms are sodium atoms.

[4] The article according to any one of [1] to [3], wherein the silicon oxide in the silicon oxide layer contains a condensate of silicic acid or a hydrolytic condensate of alkoxysilane.

[5] The article according to any one of [1] to [4], wherein the silicon oxide in the silicon oxide layer contains a vapor deposition material of silicon oxide containing an alkali metal atom.

[6] The article according to any one of [1] to [5], wherein the fluorine-containing compound is a compound having a hydrolyzable silyl group and a poly (oxyperfluoroalkylene) chain.

[7] A process for producing an article having a water-and oil-repellent layer, characterized by forming a silicon oxide layer containing an alkali metal atom on the surface of a substrate using a silicon oxide-forming material comprising a silicon oxide precursor and an alkali metal source,

then, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the surface of the silicon oxide layer,

wherein the silicon oxide layer is formed such that the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³The above.

[8] The production process according to [7], wherein the silicon oxide layer is formed on the surface of the substrate using a coating liquid containing at least 1 silicon oxide precursor selected from the group consisting of silicic acid, a partial condensate of silicic acid, tetraalkoxysilane, and a partial condensate thereof, and an alkali metal source and a solvent.

[9] The production method according to item [7], wherein the silicon oxide layer is formed on the surface of the substrate using a silicon oxide containing an alkali metal atom.

[10] The production method according to item [9], wherein the content of the alkali metal atom in the silicon oxide containing an alkali metal atom is 200ppm or more with respect to a silicon atom.

[11] The production method according to item [9] or [10], wherein a method of forming the silicon oxide layer is an evaporation method.

[12]According to [7]～[11]The production method of any one of the above, wherein the average concentration of alkali metal atoms in the region is 4.0 × 10²²atoms/cm³The following.

[13] The production method according to any one of [7] to [12], wherein at least a part of the alkali metal atoms are sodium atoms.

[14] The production method according to any one of [7] to [13], wherein the surface of the substrate is subjected to corona discharge treatment, plasma treatment or plasma graft polymerization treatment, and then the silicon oxide layer is formed on the treated surface of the substrate.

[15] An evaporation source includes a silicon oxide containing an alkali metal atom.

[16]A substrate with a silicon oxide layer, which is used for forming a water-and-oil repellent layer on an exposed surface of the silicon oxide layer by using a fluorine-containing compound having a hydrolyzable silyl group, and which comprises a substrate and a silicon oxide layer containing an alkali metal atom provided on a surface of the substrate, wherein the average value of the concentration of the alkali metal atom in a region having a depth of 0.1 to 0.3nm from the exposed surface of the silicon oxide layer is 2.0 × 10¹⁹atoms/cm³The above substrate with a silicon oxide layer is formed.

[17]A fluorine-containing compound having a hydrolyzable silyl group, which is used for forming a water-and oil-repellent layer on an exposed surface of a silicon oxide layer in a substrate with a silicon oxide layer, wherein the substrate with a silicon oxide layer has a substrate and a silicon oxide layer containing an alkali metal atom provided on a surface of the substrate, and an average value of the concentrations of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the exposed surface of the silicon oxide layer is 2.0 × 10¹⁹atoms/cm³The above.

ADVANTAGEOUS EFFECTS OF INVENTION

The water-and oil-repellent layer of the water-and oil-repellent layer-bearing article of the present invention is excellent in abrasion resistance.

According to the method for producing a water-and oil-repellent layer-bearing article of the present invention, a water-and oil-repellent layer-bearing article having excellent abrasion resistance of the water-and oil-repellent layer can be produced.

Drawings

Fig. 1 is a sectional view showing an example of the water-and oil-repellent layer-bearing article of the present invention.

FIG. 2 is a graph showing the relationship between the depth from the surface in contact with the water-and oil-repellent layer of the substrate having a silicon oxide layer and the sodium concentration obtained by TOF-SIMS for that depth.

Fig. 3 is an enlarged view of the horizontal axis of fig. 2.

Detailed Description

In the present specification, the compound represented by formula (1) will be referred to as compound (1). The compounds represented by other formulae are also described in the same manner.

The following terms in the present specification have the following meanings.

"alkali metal" refers to lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs).

"hydrolyzable silyl group" refers to a group that can form a silanol group (Si-OH) by a hydrolysis reaction. For example-SiR in formula (1)¹³ _n1X¹ _3-n1。

"etheric oxygen atom" means an oxygen atom forming an ether bond (-O-) between carbon and carbon atoms. The chemical formula of oxyperfluoroalkylene is shown with its oxygen atom shown on the right side of perfluoroalkylene.

[ articles with Water-and oil-repellent layers ]

The article with water-repellent and oil-repellent layer of the present invention has: base material: water-repellent oil-repellent layer: and a silicon oxide layer containing an alkali metal atom, which is present between the substrate and the water-and oil-repellent layer.

Fig. 1 is a sectional view showing an example of the water-and oil-repellent layer-bearing article of the present invention. The water-and oil-repellent layer-bearing article 10 has: a base material 12; a silicon oxide layer 14 formed on the surface of the substrate 12; and a water-and oil-repellent layer 16 formed on the surface of the silicon oxide layer 14.

(substrate)

The substrate in the present invention is not particularly limited as long as it is required to impart water-and oil-repellency. Examples of the material of the substrate include metal, resin, glass, sapphire, ceramic, stone, and a composite material thereof. The glass may be chemically strengthened.

As the substrate, a substrate for a touch panel and a substrate for a display are preferable, and a substrate for a touch panel is particularly preferable. The substrate for touch panels has light-transmitting properties. "having light transmittance" means that the composition has a light transmittance according to JIS R3106: 1998(ISO 9050: 1990) has a visible light transmittance of 25% or more in the normal incidence type. As a material of the substrate for a touch panel, glass or a transparent resin is preferable.

The base material may be obtained by subjecting one surface or both surfaces to corona discharge treatment, plasma treatment, or plasma graft polymerization treatment. The surface of the substrate on the side on which the treatment is performed is preferably subjected to the treatment on the surface on the side in contact with the silicon oxide layer, from the viewpoint that the adhesion between the substrate and the silicon oxide layer is more excellent, and as a result, the abrasion resistance of the water-and oil-repellent layer is more excellent. Among these treatments, corona discharge treatment is preferable in terms of more excellent abrasion resistance of the water-and oil-repellent layer.

Since the surface modification of the substrate tends to change in proportion to the input power, it is preferable to use the largest possible discharge amount (W.min/m) depending on the type of the substrate²) A corona treatment is performed.

(silicon oxide layer)

The silicon oxide layer contains silicon oxide and alkali metal atoms. From the viewpoint of ease of production, silicon oxide and sodium are preferably contained. The silicon oxide is preferably a condensate of silicic acid and a hydrolytic condensate of alkoxysilane. The condensate of silicic acid is more preferable because it has more excellent adhesion to the water-and oil-repellent layer and as a result, the water-and oil-repellent layer has more excellent abrasion resistance.

The thickness of the silicon oxide layer is preferably 2 to 200nm, particularly preferably 2 to 20 nm. When the thickness of the silicon oxide layer is equal to or more than the lower limit of the above range, the effect of improving the adhesion by the silicon oxide layer can be easily obtained sufficiently. When the thickness of the silicon oxide layer is equal to or less than the upper limit of the above range, the abrasion resistance of the silicon oxide layer itself becomes high. The method for measuring the thickness of the silicon oxide layer is not particularly limited, and examples thereof include a method of observing a cross section of the silicon oxide layer by an electron microscope (SEM, TEM, or the like), and a method using an optical interference film thickness meter, a spectroscopic ellipsometer, a step gauge (step gauge), or the like.

In the silicon oxide layer, the average concentration of alkali metal atoms in a region having a depth of 0.1 to 0.3nm from the surface in contact with the water-and oil-repellent layer is 2.0 × 10¹⁹atoms/cm³Above, preferably 5.0 × 10¹⁹atoms/cm³Above, particularly preferably 1.5 × 10²⁰atoms/cm³The above. When the average value of the alkali metal atom concentration is not less than the lower limit value, the adhesion between the silicon oxide layer and the water-and oil-repellent layer is excellent, and as a result, the water-and oil-repellent layer is excellent in abrasion resistance. The reason is not clear, but the mechanism is considered as follows. That is, the high average concentration of the alkali metal atoms means that a large amount of Si — OM (where M is an alkali metal) having high reactivity is present on the surface of the silicon oxide layer. The reactivity of Si-OM with silanol group (Si-OH) formed by hydrolysis reaction of hydrolyzable silyl group in fluorine-containing compound having hydrolyzable silyl group used for forming water-and oil-repellent layer is high. Therefore, by the presence of a large amount of Si — OM, the bonding point of the silicon oxide layer to the water-and oil-repellent layer, i.e., the Si — O — Si bond, increases. As a result, the water-and oil-repellent layer is less likely to peel off and the water-and oil-repellent layer is excellent in abrasion resistance.

In the present invention, the concentration of the alkali metal atom means the concentration of the alkali metal atom when the region contains only 1 kind of alkali metal atom, and means the total concentration of the alkali metal atoms when the region contains 2 or more kinds of alkali metal atoms.

Therefore, the alkali metal atoms contained in the region are 2 or more and the average value of the concentrations of the alkali metal atoms is less than the lower limit value, as long as the total average value of the concentrations of the alkali metal atoms is not less than the lower limit value.

Specifically, for example, the alkali metal atom contained in the region contains Na, and the average value of the Na atom concentration in the regionIs 2.0 × 10¹⁹atoms/cm³In addition, the alkali metal atoms contained in the region are Na and K, even if the average value of the Na atom concentration and the average value of the K atom concentration in the region are less than 2.0 × 10¹⁹atoms/cm³When the sum of the average value of the Na atom concentration and the average value of the K atom concentration is 2.0 × 10¹⁹atoms/cm³The above conditions satisfy the requirement of the alkali metal atom concentration in the present invention.

The upper limit of the average value of the alkali metal atom concentration is not particularly limited, but is preferably 4.0 × 10 from the viewpoint of sufficiently forming an Si-O-Si bond in the silicon oxide layer and sufficiently securing the mechanical properties of the silicon oxide layer²²atoms/cm³Particularly preferably 1.0 × 10²²atoms/cm³。

The average of the concentrations of the alkali metal atoms is determined as follows: the concentration of alkali metal atoms is determined by obtaining a depth-wise distribution (profile) of the concentration of alkali metal atoms by TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) depth-wise analysis by Ion sputtering, and then calculating the average concentration of alkali metal atoms in a region of 0.1 to 0.3nm in depth of the distribution.

TOF-SIMS depth direction analysis based on ion sputtering is performed by alternately repeating TOF-SIMS-based measurement and etching of a surface based on ion sputtering using an ion gun built in the TOF-SIMS apparatus.

In the present invention, the reason why the concentration of alkali metal atoms in the region having a depth of less than 0.1nm from the surface in contact with the water-and oil-repellent layer in the silicon oxide layer is excluded is because: when the surface of the silicon oxide layer is contaminated with an external substance containing an alkali metal, the contamination caused by the alkali metal is reflected in the alkali metal atom concentration distribution in the region, and therefore there is a fear that the concentration of the alkali metal atom derived from Si — OM in the silicon oxide layer cannot be accurately measured.

From the viewpoint of abrasion resistance, the surface roughness (Ra) of the surface of the silicon oxide layer (the interface with the water-and oil-repellent layer) as measured by a scanning probe microscope is preferably 0.5nm or more. The upper limit of the roughness is not particularly limited, but is preferably 10nm or less.

The silicon oxide layer is not particularly limited, and is preferably a layer formed on the surface of the substrate by a wet coating method using a coating solution formed from a solution containing a precursor of silicon oxide, an alkali metal source, and a solvent (water, a water-soluble organic solvent, or the like), or a layer formed on the surface of the substrate by a dry coating method using silicon oxide containing an alkali metal atom. The details will be described later.

(Water and oil repellent layer)

The water-and oil-repellent layer in the present invention is formed from a hydrolysis condensate of a fluorine-containing compound having a hydrolyzable silyl group.

Hydrolyzable silyl group in hydrolyzable silyl group-containing fluorine-containing compound (for example, SiR in the formula (1))¹³ _n1X¹ _3-n1) The silanol group (Si-OH) is formed by hydrolysis reaction and forms an Si-O-Si bond by condensation reaction between molecules, or the silanol group in the fluorine-containing compound forms a chemical bond (Si-O-Si bond) by condensation reaction with the silanol group (Si-OH) or OM group (Si-OM) on the surface of the silicon oxide layer. That is, the water-and oil-repellent layer in the present invention contains the hydrolyzable silyl group-containing compound having a hydrolyzable silyl group in a state in which a part or all of the hydrolyzable silyl groups have undergone hydrolysis reaction and condensation reaction.

The thickness of the water-repellent and oil-repellent layer is preferably 1 to 100nm, and particularly preferably 1 to 50 nm. When the thickness of the water-and oil-repellent layer is not less than the lower limit of the above range, the effect by the surface treatment can be easily obtained sufficiently. When the thickness of the water-and oil-repellent layer is not more than the upper limit of the above range, the utilization efficiency is high.

In the present invention, the thickness obtained by thin film analysis using an X-ray diffractometer is defined as the thickness of the water-and oil-repellent layer. The thickness of the water-and oil-repellent layer was calculated from the vibration period of the interference pattern obtained by an X-ray reflectance method using an X-ray diffractometer for thin film analysis (ATX-G, manufactured by RIGAKU corporation).

(fluorine-containing Compound having hydrolyzable silyl group)

The fluorine-containing compound having a hydrolyzable silyl group (hereinafter also simply referred to as "fluorine-containing compound") is not particularly limited as long as it can form a water-and oil-repellent layer. That is, the fluorine-containing compound is used to form a water-and oil-repellent layer on the exposed surface of the silicon oxide layer.

Examples of the fluorine-containing compound include a fluorine-containing compound having a fluoroalkyl group and a hydrolyzable silyl group, a fluorine-containing compound having a group containing an etheric oxygen atom between carbon atoms of the fluoroalkyl group and a hydrolyzable silyl group, and the like. The fluorine-containing compound is preferably a fluorine-containing compound having a perfluoroalkyl group and a hydrolyzable silyl group, or a fluorine-containing compound having a group containing an etheric oxygen atom between carbon atoms of the perfluoroalkyl group and a hydrolyzable silyl group, in view of forming a water-and-oil-repellent layer excellent in water-and-oil repellency, fingerprint stain removability, lubricity, and the like. Further, as the fluorine-containing compound, a fluorine-containing compound having a fluoroalkyl group, a hydrolyzable silyl group, and a poly (oxyfluoroalkylene) chain (hereinafter also referred to as "fluorine-containing ether compound") is also preferable in that a water-and-oil-repellent layer excellent in water-and-oil repellency, fingerprint stain removability, lubricity, and the like can be formed.

The fluoroalkyl group is preferably a fluoroalkyl group having 1 to 20 carbon atoms, more preferably a fluoroalkyl group having 1 to 10 carbon atoms, further preferably a fluoroalkyl group having 1 to 6 carbon atoms, and particularly preferably a linear fluoroalkyl group having 1 to 6 carbon atoms, because it is excellent in water and oil repellency and has little burden on the environment.

The perfluoroalkyl group is preferably a C1-20 perfluoroalkyl group, more preferably a C1-10 perfluoroalkyl group, still more preferably a C1-6 perfluoroalkyl group, and particularly preferably a C1-6 linear perfluoroalkyl group, because it has excellent water and oil repellency and places little burden on the environment.

Examples of the fluorine-containing compound having a perfluoroalkyl group and a hydrolyzable silyl group include compounds represented by the formula (3) described in the paragraphs [0010] and [0022] of Japanese patent laid-open publication No. 2009-139530.

The hydrolyzable silyl group in the fluorine-containing ether compound is preferably 2 or more, and particularly preferably 3 or more, from the viewpoint of more excellent abrasion resistance of the water-and oil-repellent layer. The upper limit is not particularly limited, but 15, and particularly 12 are preferable from the viewpoint of ease of production.

The poly (oxyfluoroalkylene) chain preferably contains an oxyfluoroalkylene group having 1 to 10 carbon atoms, and particularly preferably contains an oxyperfluoroalkylene group having 1 to 10 carbon atoms. The water-and oil-repellent layer preferably contains a plurality of oxyperfluoroalkylene groups having 1 to 10 carbon atoms, from the viewpoint of further improving the abrasion resistance and fingerprint stain removal performance. Examples thereof include: a poly (oxyfluoroalkylene) chain containing a plurality of oxyperfluoroalkylene groups having 1 carbon number and a plurality of oxyperfluoroalkylene groups having 2 carbon number, a poly (oxyfluoroalkylene) chain containing a plurality of oxyperfluoroalkylene groups having 1 carbon number and a plurality of oxyperfluoroalkylene groups having 3 carbon number, a poly (oxyfluoroalkylene) chain containing a plurality of oxyperfluoroalkylene groups having 2 carbon number and a plurality of oxyperfluoroalkylene groups having 3 carbon number, and a poly (oxyfluoroalkylene) chain containing a plurality of oxyperfluoroalkylene groups having 2 carbon number and a plurality of oxyperfluoroalkylene groups having 4 carbon number. The arrangement of the plurality of oxyperfluoroalkylene groups may be any of block, random and alternate. When the number of carbon atoms of the oxyperfluoroalkylene group is 2 or more, a linear oxyperfluoroalkylene group is preferable.

The poly (oxyperfluoroalkylene) chain is particularly preferably one in which a linear oxyperfluoroalkylene group having 2 carbon atoms and a linear oxyperfluoroalkylene group having 4 carbon atoms are alternately arranged.

(Compound (X))

The fluorine-containing ether compound includes a compound (X).

[A¹-O-(R^f1O)_m1]_a-Q-[SiR¹³ _n1X¹ _3-n1]_b···(X)

Wherein A is¹Is C1-20 perfluoroalkyl, R^f1Is a C1-10 fluoroalkylene group, m1 is an integer of 2-210, (R)^f1O)_m1May contain 2 or more kinds of R having different carbon numbers^f1O, a and b are each independently an integer of 1 or more, Q is a linking group having a valence of (a + b), R¹³Is a hydrogen atom or a 1-valent hydrocarbon group, X¹N1 is an integer of 0 to 2, 3 [ SiR ] s¹³ _n1X¹ _3-n1]May not all be the same group.

<A¹Base of>

As A¹The water-and oil-repellent layer is preferably a C1-20 perfluoroalkyl group, more preferably a C1-10 perfluoroalkyl group, still more preferably a C1-6 perfluoroalkyl group, and particularly preferably a C1-3 perfluoroalkyl group, from the viewpoint of further excellent lubricity and abrasion resistance.

<(R^f1O)_m1>

R^f1Preferably straight chain. In addition, R^f1May be a perfluoroalkylene group or a fluoroalkylene group containing 1 or more hydrogen atoms.

As R^f1The same groups as the oxyperfluoroalkylene group constituting the above-mentioned preferred poly (oxyperfluoroalkylene) chain are preferable.

m1 is an integer of 2 to 210, preferably an integer of 5 to 160, particularly preferably an integer of 10 to 110. When m1 is not less than the lower limit of the above range, the water-and oil-repellency of the water-and oil-repellent layer is excellent. When m1 is not more than the upper limit of the above range, the water-and oil-repellent layer is excellent in abrasion resistance.

(R^f1O)_m1In (B), 2 or more kinds of R having different carbon numbers are present^f1In the case of O, each R^f1The bonding order of O is not limited. For example, there are 2R^f1When O is present, 2R^f1The O may be arranged randomly, alternately, or in blocks.

< a and b >

a is preferably an integer of 1 to 10, particularly preferably an integer of 1 to 4.

The (a + b) is preferably an integer of 2 to 15, particularly preferably an integer of 2 to 12.

When a is 1, an integer of 1 to 10 is preferable, and 1 to 5 is particularly preferable.

When a is an integer of 2 or more, b is preferably an integer of 1 or more, more preferably an integer of 1 to 10, and particularly preferably an integer of 1 to 4.

< Q group >

Examples of Q include: a (a + b) -valent alkyl group, a group in which various atoms or groups such as an etheric oxygen atom and an amide group are inserted between carbon atoms and carbon atoms of the alkyl group, a group in which a part of hydrogen atoms bonded to carbon atoms of these groups is substituted with fluorine atoms, and the like.

<SiR¹³ _n1X¹ _3-n1Base of>

SiR¹³ _n1X¹ _3-n1Is a hydrolyzable silyl group.

X¹Is a hydrolyzable group. The hydrolyzable group is a group that forms a hydroxyl group by a hydrolysis reaction. That is, Si-X at the terminal of the compound (X)¹Silanol groups (Si-OH) are formed by hydrolysis reactions.

As X¹Examples thereof include an alkoxy group, a halogen atom, an acyl group, and an isocyanate group (-NCO). The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms.

R¹³Is a hydrogen atom or a 1-valent hydrocarbon group. Examples of the 1-valent hydrocarbon group include an alkyl group, a cycloalkyl group, an alkenyl group, and an allyl group.

As R¹³The hydrocarbon group having a valence of 1 is preferable, and the saturated hydrocarbon group having a valence of 1 is particularly preferable. The number of carbon atoms of the 1-valent saturated hydrocarbon group is preferably 1 to 6, more preferably 1 to 3, and particularly preferably 1 to 2. R¹³When the number of carbon atoms of (b) is in this range, the compound (X) can be easily produced.

n1 is preferably 0 or 1, particularly preferably 0. By the presence of a plurality of X in 1 hydrolyzable silyl group¹The adhesiveness to the base material becomes stronger.

3 SiRs in Compound (X)¹³ _n1X¹ _3-nAll may or may not be the same group. In view of ease of production of the compound (X), it is preferable that all of the groups are the same.

Specific examples of the compound (X) include: the compound (1) described later, International publication Nos. 2013/042732, 2013/121984, 2013/121985, 2013/121986, 2014/163004, 2015/087902, 2017/038830, 2017/038832, 2017/187775, 2014-080473 and 2015-199906, the fluorine-containing ether compound described in International publication Nos. 2011/059430 and 2011/060047, the silicon-containing organic fluorine-containing polymer described in Japanese patent No. 2874715, the perfluoropolyether-modified aminosilane described in Japanese patent publication Nos. 327772 and 11-029585, the fluorinated siloxane described in Japanese patent publication No. 2002-506887, and the like, Fluorinated modified hydrogen-containing polymers described in Japanese patent No. 4138936, polymer-modified silanes containing a fluoropolyether group described in Japanese patent laid-open Nos. 2015-199906, 2016-204656, 2016-210854 and 2016-222859, fluorine-containing organosilane compounds described in International publication No. 2012/064649, organosilicon compounds described in Japanese patent laid-open No. 2000-144097, organosilicon compounds described in Japanese patent laid-open No. 2008-534696, silane compounds containing a perfluoro (poly) ether described in patent document 1, fluorine-containing oxyalkylene polymers described in patent document 2, compounds described in patent document 3, 2014-070163 and US 2010/0129672, and the like.

Examples of commercially available products of the compound (X) include KY-100 series (KY-178, KY-185, KY-195, etc.) manufactured by shin-Etsu chemical Co., Ltd, Afluid (registered trademark) S550 manufactured by Asahi glass company, DAIKINDUSTRIES, Optool (registered trademark) DSX manufactured by Ltd, Optool (registered trademark) AES, Optool (registered trademark) UF, and Optool (registered trademark) UD 509.

(Compound (1))

The compound (1) is an example of the compound (X).

A¹-O-(R^f1O)_m1-Q¹-[C(O)N(R¹)]_p1-Q²-[SiR¹³ _n1X¹ _3-n1]_b2···(1)

Wherein Q is²is-R¹¹-C(-R¹²-)₃Or R¹³，Q²is-R¹¹-C(-R¹²-)₃When b2 is 3, Q²Is R¹³At time b2 is 1.

In the above compound (1), A¹、R^f1、m1、R¹³、X¹And n1 is the same as the above formula (X), Q¹Is a linear C1-10 fluoroalkylene group, R¹Is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, p1 is 0 or 1, R¹¹Is a single bond, an alkylene group, at the terminal of the alkylene group (wherein, with C (-R)¹²-)₃The end of one side of the bond. ) A group having an etheric oxygen atom, a group having an etheric oxygen atom between carbon atoms of an alkylene group having 2 or more carbon atoms, or a group having a C (-R) at the terminal of an alkylene group having 2 or more carbon atoms¹²-)₃The end of one side of the bond. ) And a group having an etheric oxygen atom between carbon-carbon atoms, R¹²、R¹³Each independently is an alkylene group, a group having an etheric oxygen atom at the terminal of the alkylene group (not including the terminal on the side bonded to Si), or a group having an etheric oxygen atom between carbon-carbon atoms of an alkylene group having 2 or more carbon atoms.

<Q¹Base of>

Q¹The perfluoroalkylene group may be a linear perfluoroalkylene group, or a linear fluoroalkylene group containing 1 or more hydrogen atoms. According to Q¹The compound (1) having a straight chain can form a water-and oil-repellent layer having excellent abrasion resistance and lubricity.

<[C(O)N(R¹)]_p1Base of>

When p is 1, it has an amide bond with Q¹Is [ C (O) N (R) ]¹)]At least 1 fluorine atom is bonded to the carbon atom at the end of the bonded side, so that the polarity of the amide bond becomes small, and the water-and oil-repellency of the water-and oil-repellent layer is not easily lowered. From the viewpoint of ease of production, p1 may be selected to be 0 or 1.

As [ C (O) N (R)¹)]_p1In the radical R¹From the viewpoint of ease of production of the compound (1), a hydrogen atom is preferable. R¹In the case of an alkyl group, the alkyl group is preferably an alkyl group having 1 to 4 carbon atoms.

<R¹¹Base of>

When p1 is 0, it is regarded as R¹¹FromThe compound (1) is preferably selected from the group consisting of a single bond, -CH, and mixtures thereof in view of ease of production₂O-、-CH₂OCH₂-、-CH₂OCH₂CH₂O-and-CH₂OCH₂CH₂OCH₂Group of (wherein, left and Q)¹And (4) bonding. ).

When p1 is 1, it is taken as R¹¹From the viewpoint of ease of production of the compound (1), it is preferably selected from the group consisting of a single bond, -CH₂-and-CH₂CH₂-a group of the group consisting.

<R¹²Radical, R¹³Base of>

As R¹²、R¹³From the viewpoint of ease of production of the compound (1), each is preferably independently selected from the group consisting of-CH₂CH₂-、-CH₂CH₂CH₂-、-CH₂OCH₂CH₂CH₂-、-OCH₂CH₂CH₂Groups of the group (wherein the right side is bonded to Si).

3 Rs in Compound (1)¹²All may or may not be the same group.

<-(R^f1O)_m1-Q¹Preferred embodiment of (1)>

As- (R) in the Compound (1)^f1O)_m1-Q¹From the viewpoint of further excellent abrasion resistance and fingerprint stain removability of the water-and oil-repellent layer, -Q is preferred¹¹-(R^F1O)_m10-Q¹²-. Wherein Q is¹¹A straight-chain fluoroalkylene group containing 1 or more hydrogen atoms which is a single bond, at the end of the straight-chain fluoroalkylene group containing 1 or more hydrogen atoms (wherein A is excluded)¹-end of one side of O-bond. ) A group having an etheric oxygen atom, a group having an etheric oxygen atom between carbon-carbon atoms of a linear fluoroalkylene group having 2 or more carbon atoms and containing 1 or more hydrogen atoms, or a group having a linear fluoroalkylene group having 2 or more carbon atoms and containing 1 or more hydrogen atoms at the terminal (wherein A is not included therein¹-end of one side of O-bond. ) And a carbon-carbon atom spacerA group having an etheric oxygen atom (wherein the oxygen number is 10 or less), R^F1Is a linear perfluoroalkylene group, m10 is an integer of 2 to 200, (R)^F1O)_m10May contain 2 or more kinds of R having different carbon numbers^F1O，Q¹²The fluorine-containing polymer is a linear perfluoroalkylene group, a linear fluoroalkylene group containing 1 or more hydrogen atoms, or a group having an etheric oxygen atom between carbon-carbon atoms of a linear fluoroalkylene group containing 1 or more hydrogen atoms and having 2 or more carbon atoms.

<Q¹¹Base of>

Q¹¹In the case of a linear fluoroalkylene group containing 1 or more hydrogen atoms, or a group containing an etheric oxygen atom between carbon-carbon atoms of a linear fluoroalkylene group containing 1 or more hydrogen atoms and having 2 or more carbon atoms, and Q¹¹And (R)^F1O)_m10Q when no etheric oxygen atom is present at the end of the bonded side¹¹And (R)^F1O)_m10At least 1 hydrogen atom is bonded to the carbon atom at the end of the bonded side.

As Q¹¹From the viewpoint of ease of production of the compound (11), it is preferable that the compound is a single bond or a compound selected from the group consisting of-CHFCF₂OCH₂-、-CF₂CHFCF₂OCH₂-、-CF₂CF₂CHFCF₂OCH₂-、-CF₂CF₂OCHFCF₂OCH₂-、-CF₂CF₂OCF₂CF₂OCHFCF₂OCH₂-、-CF₂CH₂OCH₂-、-CF₂CF₂OCF₂CH₂OCH₂Group of (wherein, left side is A)¹-O bonding. ).

<(R^F1O)_m10>

R^F1Preferred embodiments of (1) and the above-mentioned R^f1The preferred embodiments of (a) are the same.

The preferable range of m10 is the same as the preferable range of m1 described above.

(R^F1O)_m10In (B), 2 or more kinds of R having different carbon numbers are present^F1When O is present, each R^F1Of OThe bonding order is not limited.

As (R)^F1O)_m10For example, { (CF) can be mentioned₂O)_m11(CF₂CF₂O)_m12}、(CF₂CF₂O)_m13、(CF₂CF₂CF₂O)_m14、(CF₂CF₂O-CF₂CF₂CF₂CF₂O)_m15And the like.

Wherein m11 is an integer of 1 or more, m12 is an integer of 1 or more, m11+ m12 is an integer of 2 to 200, and m11 CF₂O and m12 CF₂CF₂The bonding order of O is not limited. m13 and m14 are integers of 2 to 200, and m15 is an integer of 1 to 100. In addition, { (CF)₂O)_m11(CF₂CF₂O)_m12Means having m11 (CF)₂O) and m12 (CF)₂CF₂O), (CF)₂O) and (CF)₂CF₂O) random copolymer chains.

<Q¹²Base of>

When p1 is 0, e.g. in (R)^F1O)_m10Is { (CF)₂O)_m11(CF₂CF₂O)_m12And (CF)₂CF₂O)_m13When is, Q¹²Is C1 perfluoroalkylene, in (R)^F1O)_m10Is (CF)₂CF₂CF₂O)_m14When is, Q¹²Is C2 perfluoroalkylene, in (R)^F1O)_m10Is (CF)₂CF₂O-CF₂CF₂CF₂CF₂O)_m15When is, Q¹²Is a C3 linear perfluoroalkylene group.

When p1 is 1, it is Q¹²The following groups may be mentioned.

(i) A perfluoroalkylene group.

(ii) In and (R)^F1O)_m10One side of the bond has R^FCH₂O (wherein, R^FIs a perfluoroalkylene group. ) And is between C (O) N (R)¹) Having on one side of the bond a fluoroalkylene group containing 1 or more hydrogen atoms (optionally in the presence of carbon-Having etheric oxygen atoms between carbon atoms. ) A group of (1).

Q as (ii)¹²The following groups are preferred in view of ease of production of the compound (1).

-R^FCH₂O-CF₂CHFOCF₂CF₂CF₂-、-R^FCH₂O-CF₂CHFCF₂OCF₂CF₂-、-R^FCH₂O-CF₂CHFCF₂OCF₂CF₂CF₂-、-R^FCH₂O-CF₂CHFOCF₂CF₂CF₂OCF₂CF₂-。

According to Q¹²The compound (1) having a straight chain can form a water-and oil-repellent layer having excellent abrasion resistance and lubricity.

< preferred embodiment of Compound (1) >

Examples of the compound (1) include compounds of the following formula. The compound is preferable in that it is easy to industrially produce and handle, and the water-and oil-repellent layer is more excellent in water-and oil-repellency, abrasion resistance, fingerprint stain removability, lubricity, and appearance.

PFPE-CH₂OCH₂CH₂CH₂-Si(OCH₃)₃

PFPE-CH₂OCH₂CH₂CH₂-Si(OCH₂CH₃)₃

PFPE-CH₂OCH₂CH₂CH₂-Si(CH₃)(OCH₃)₂

PFPE-C(O)NH-CH₂CH₂CH₂-Si(OCH₃)₃

PFPE-C(O)NH-CH₂CH₂CH₂-Si(OCH₂CH₃)₃

PFPE-C(O)NH-CH₂CH₂CH₂-Si(CH₃)(OCH₃)₂

Wherein PFPE is a polyfluoropolyether chain, i.e. A¹-O-Q¹¹-(R^F1O)_m10-Q¹²-. The preferred embodiment of PFPE is to use the above-mentioned preferred A¹、Q¹¹、(R^F1O)_m10And Q¹²Are combined.

[ Process for producing Water-and oil-repellent layer-bearing article ]

The method for manufacturing the article with the water-repellent and oil-repellent layer comprises the following steps: (a) forming a silicon oxide layer containing an alkali metal atom on a surface of a substrate using a silicon oxide forming material containing a silicon oxide precursor and an alkali metal source, and then (b) forming a water-and oil-repellent layer formed of a hydrolysis condensate of a fluorine-containing compound having a hydrolyzable silyl group on a surface of the silicon oxide layer, wherein the silicon oxide layer is formed into the silicon oxide layer having the alkali metal atom concentration.

Examples of the silicon oxide precursor include silicic acid, a partial condensate of silicic acid, an alkali metal silicate, a silane compound having a hydrolyzable group bonded to a silicon atom, a partial hydrolytic condensate of the silane compound, and the like. Silicon oxide can be produced by subjecting silicic acid or a partial condensate thereof to dehydration condensation, subjecting an alkali metal silicate to acid or a cation exchange resin to form silicic acid or a partial condensate thereof, and subjecting the formed silicic acid or partial condensate thereof to dehydration condensation. Examples of the hydrolyzable group in the silane compound having a hydrolyzable group bonded to a silicon atom include an alkoxy group, a chlorine atom and the like. The hydrolyzable group of the silane compound is hydrolyzed to form a hydroxyl group, and the resulting silanol compound is subjected to dehydration condensation to produce a silicon oxide. Examples of the silane compound having a hydrolyzable group bonded to a silicon atom include alkoxysilanes such as tetraalkoxysilane and alkyltrialkoxysilane, and tetrachlorosilane.

As the silicon oxide precursor, silicic acid, a partial condensate of silicic acid, tetraalkoxysilane, and a partial hydrolytic condensate thereof are preferable.

Examples of the alkali metal source include an alkali metal hydroxide, a water-soluble alkali metal salt, and the like. Examples of the water-soluble alkali metal salt include alkali metal carbonates, alkali metal hydrogencarbonates, alkali metal carbonates, and alkali metal nitrates. As the alkali metal source, an alkali metal hydroxide and an alkali metal carbonate are preferable.

Further, an alkali metal silicate may be used as the silicon oxide precursor and the alkali metal source. As described above, the alkali metal silicate can form a silicon oxide via silicic acid, and at this time, a small amount of alkali metal remains in the generated silicon oxide. Therefore, by intentionally adjusting the amount of the remaining alkali metal, a silicon oxide containing a predetermined amount of alkali metal atoms can be obtained.

As a method for forming a silicon oxide layer containing an alkali metal atom, (a1) or (a2) described below is preferable. (a1) The method (b) is a method using the wet coating, and the method (a2) is a method using the dry coating.

(a1) The method comprises the following steps A method for forming a silicon oxide layer on a substrate surface using a coating liquid containing at least 1 silicon oxide precursor selected from the group consisting of silicic acid, a partial condensate of silicic acid, an alkoxysilane and a partial hydrolysis condensate thereof, and an alkali metal source and a solvent.

(a2) The method comprises the following steps A method for forming the silicon oxide layer on the surface of a substrate by using a silicon oxide containing an alkali metal atom.

(a1)

The coating liquid for forming a silicon oxide layer preferably contains at least 1 selected from the group consisting of silicic acid and a partial condensate thereof as a silicon oxide precursor, and particularly preferably contains a partial condensate of silicic acid, from the viewpoint of facilitating formation of a silicon oxide layer.

Alkali metal silicates are preferably used as raw materials for the production of silicic acid and its partial condensates. By using the alkali metal silicate, the silicon oxide layer to be formed can contain alkali metal atoms at a predetermined concentration. Further, the concentration of the alkali metal atom in the silicon oxide layer to be formed may be adjusted by using an alkali metal source such as an alkali metal hydroxide.

Specifically, a method of preparing the alkali metal silicate aqueous solution by desalting to obtain an aqueous silicic acid solution and then adding a water-soluble organic solvent to the aqueous silicic acid solution is preferable. By appropriately selecting the desalting treatment conditions, the aqueous silicic acid solution can be made to contain a preferred amount of alkali metal atoms. As a method of desalting treatment, for example, a method of mixing and stirring an alkali metal silicate aqueous solution and a cation exchange resin and then removing the cation exchange resin is exemplified. As the alkali metal silicate that can be used in this method, sodium silicate is preferred.

As the alkali metal silicate, M may be mentioned₂O·nSiO₂Specific examples of the silicate include metasilicate (M)₂SiO₃) Orthosilicate (M)₄SiO₄) Disilicate (M)₂Si₂O₅) Tetrasilicate (M)₂Si₄O₉) And the like.

For example, sodium silicate may be Na as defined in JIS K1408-1966₂O·nSiO₂Specifically, sodium metasilicate (Na) may be mentioned₂SiO₃) Sodium orthosilicate (Na)₄SiO₄) Sodium disilicate (Na)₂Si₂O₅) Sodium tetrasilicate (Na)₂Si₄O₉) And the like.

The solvent is preferably water or a water-soluble organic solvent. Examples of the water-soluble organic solvent include alcohol-based organic solvents, ketone-based organic solvents, ether-based organic solvents, ester-based organic solvents, and the like, and alcohol-based organic solvents are preferable. Examples of the alcohol-based organic solvent include isopropyl alcohol, ethyl alcohol, and n-butyl alcohol.

Solid content concentration (SiO) of coating liquid₂Converted) is preferably 0.001 to 10% by mass, particularly preferably 0.1 to 3% by mass.

Examples of the method for wet coating the surface of the substrate with the coating liquid include spin coating, wipe coating, spray coating, doctor blade (squeegee coat) method, dip coating, die coating, ink jet method, flow coating, roll coating, casting, Langmuir-Blodgett method, and gravure coating.

The surface of the substrate is wet-coated with the coating liquid to form a wet film, and then the solvent of the wet film is removed to condense silicic acid and a partial condensate thereof, thereby forming a silicon oxide layer.

The temperature in the solvent removal of the wet film and the temperature in the condensation of the silicic acid and its partial condensate are preferably 0 to 600 ℃, and particularly preferably 200 to 600 ℃ in view of forming a dense silicon oxide layer.

(a2)

Examples of the method of dry coating using a silicon oxide containing an alkali metal atom include a vacuum deposition method, a CVD method, a sputtering method, and the like, because the process is easy and convenient. Vacuum deposition is particularly preferred in view of simplicity of the apparatus.

In the case of depositing 2 or more types of silicon oxides containing alkali metal atoms by vacuum deposition, these may be used as one deposition source or may be co-deposited as separate deposition sources. In particular, 1 kind of vapor deposition source formed of silicon oxide containing an alkali metal atom is preferably used. For example, in the case of forming a silicon oxide layer containing 2 or more alkali metal atoms, 1 kind of vapor deposition source formed of silicon oxide containing 2 or more alkali metal atoms is preferably used.

The silicon oxide containing an alkali metal atom used in a dry coating method such as a vapor deposition source in a vacuum vapor deposition method is preferably a silicon oxide containing an alkali metal atom in which the content of an alkali metal atom is 200ppm or more relative to Si. The content of the alkali metal atom is more preferably 1,000ppm or more, particularly preferably 10,000ppm or more based on Si. When the content of the alkali metal atom is not less than the lower limit of the above range, the formed silicon oxide layer is excellent in adhesion to the water-and oil-repellent layer, and as a result, the water-and oil-repellent layer is excellent in abrasion resistance. The upper limit of the content of the alkali metal atom is preferably 200,000ppm, particularly preferably 100,000ppm, based on Si.

As a method for producing a silicon oxide containing an alkali metal atom, a method in which silicon dioxide is added to an aqueous solution containing an alkali metal source, and water is removed by stirring is given. The silica is preferably porous silica such as silica gel. Examples of the aqueous solution containing an alkali metal source include an aqueous alkali metal hydroxide solution, an aqueous alkali metal carbonate solution and the like. Further, a silicon oxide containing an alkali metal atom may be produced from the coating liquid for forming a silicon oxide layer of (a 1).

In addition, as the silicon oxide containing an alkali metal atom, the following may also be used: a porous silica gel containing an alkali metal atom, which is produced from an alkali metal silicate such as sodium silicate, or a porous silica gel containing an alkali metal atom, which is obtained by impregnating the porous silica gel with an aqueous solution containing an alkali metal source, drying the impregnated porous silica gel, and calcining the dried porous silica gel. Commercially available silicon oxides containing alkali metal atoms can be used, and examples thereof include porous spherical silica gels made of sodium silicate such as m.s.gel (trade name: AGC Si-Tech co., ltd.).

The shape of the silicon oxide containing an alkali metal atom is not particularly limited, and examples thereof include powder, beads, pellets, and cullet. Beads, pellets, and cullet are preferable because they are easily usable as a vapor deposition source. The method of producing the pellets is not particularly limited, and examples thereof include a method of molding powder compact into a pellet-like molded body. The size of the pellet-like molded article is not particularly limited, but is not preferable because if it is small, it is excessively scattered at the time of coating, and therefore, for example, the diameter is preferably 1cm or more. As a method for producing cullet, a method of cutting and crushing a material vitrified by adding calcium with a cutter can be cited.

(b)

After the silicon oxide layer containing an alkali metal atom is formed, a water-and oil-repellent layer formed of a hydrolytic condensate of a fluorine-containing compound having a hydrolyzable silyl group is formed on the exposed surface. Examples of the method include dry coating and wet coating. The exposed surface of the silicon oxide layer in the substrate with a silicon oxide layer is a surface of the silicon oxide layer on which the water-and oil-repellent layer is formed.

< Dry coating >

The dry coating method includes a vacuum deposition method, a CVD method, a sputtering method, and the like, and the vacuum deposition method is particularly preferable from the viewpoint of suppressing decomposition of the fluorine-containing compound having a hydrolyzable silyl group and from the viewpoint of simplicity of the apparatus.

The temperature during vacuum deposition is preferably 20 to 300 ℃, particularly preferably 30 to 200 ℃.

The pressure in vacuum deposition is preferably 1 × 10^-1Pa or less, particularly preferably 1 × 10^-2Pa or less.

In the dry coating, 1 kind of fluorine-containing compound having a hydrolyzable silyl group may be used alone, or a mixture of 2 or more kinds of fluorine-containing compounds having a hydrolyzable silyl group may be used, or a composition containing a fluorine-containing compound having a hydrolyzable silyl group and other components (excluding a solvent) may be used, or a solution or dispersion obtained by adding a solvent to these components may be used.

< Wet coating >

Examples of the wet coating method include spin coating, wipe coating, spray coating, blade coating, dip coating, die coating, spray coating, flow coating, roll coating, casting, Langmuir-Blodgett method, and gravure coating.

In wet coating, a coating liquid for forming a water-and oil-repellent layer is used.

The coating liquid for forming a water-and oil-repellent layer is a solution or dispersion containing a fluorine-containing compound having a hydrolyzable silyl group and a solvent.

As the solvent, an organic solvent is preferable. The organic solvent may be a fluorine-containing organic solvent or a non-fluorine-containing organic solvent, and may contain both solvents.

Examples of the fluorine-containing organic solvent include fluorinated alkanes, fluorinated aromatic compounds, fluoroalkyl ethers, fluorinated alkylamines, and fluoroalcohols.

The non-fluorine-containing organic solvent is preferably a compound containing only hydrogen atoms and carbon atoms, or a compound containing only hydrogen atoms, carbon atoms, and oxygen atoms, and examples thereof include hydrocarbon-based organic solvents, alcohol-based organic solvents, ketone-based organic solvents, ether-based organic solvents, and ester-based organic solvents.

The coating liquid for forming a water-and oil-repellent layer may contain other components and impurities (by-products generated in the production process of the fluorinated compound having a hydrolyzable silyl group, etc.) in addition to the fluorinated compound having a hydrolyzable silyl group and the solvent within a range not to impair the effects of the present invention.

Examples of the other component include known additives such as an acid catalyst and a basic catalyst which promote hydrolysis and condensation reactions of the hydrolyzable silyl group.

The solid content concentration of the coating liquid for forming a water-and oil-repellent layer is preferably 0.001 to 10 mass%, particularly preferably 0.01 to 1 mass%. The solid content concentration of the water-and oil-repellent layer-forming coating liquid was a value calculated from the mass of the water-and oil-repellent layer-forming coating liquid before heating and the mass of the water-and oil-repellent layer-forming coating liquid after heating for 4 hours by a convection dryer at 120 ℃.

< post-treatment >

(b) In order to improve the abrasion resistance of the water-and oil-repellent layer, an operation for promoting the reaction of the fluorine-containing compound having a hydrolyzable silyl group and the silicon oxide layer may be performed as necessary. Examples of such operations include heating, humidification, and light irradiation. For example, the substrate with the silicon oxide layer on which the water-and oil-repellent layer is formed is heated in an atmosphere having moisture, and the hydrolysis reaction of the hydrolyzable silyl group to the silanol group, the formation of a siloxane bond by the condensation reaction of the silanol group, the condensation reaction of the silanol group and the OM group on the surface of the silicon oxide layer with the silanol group of the fluorine-containing compound, and the like can be promoted.

After the surface treatment, a compound which is not chemically bonded to other compounds or the silicon oxide layer in the water-and-oil repellent layer can be removed as required. Specific examples of the method include a method of allowing a solvent to flow over a water-and oil-repellent layer, and a method of wiping with a cloth impregnated with a solvent.