WATER/OIL-REPELLENT COATING COMPOSITION

Abstract

The object of the present invention is to provide a water/oil-repellent coating composition for forming a film capable of attaining both water/oil repellency and abrasion resistance. The water/oil-repellent coating composition comprises: an organosilicon compound (A) and a metal compound (B), wherein at least one first hydrocarbon chain-containing group and at least one hydrolyzable group are bonded to a silicon atom in the organosilicon compound (A), where in at least one hydrolyzable group is bonded to a metal atom in the metal compound (B), wherein a second hydrocarbon chain-containing group having a length shorter than the length of the first hydrocarbon chain-containing group may be bonded to the metal atom in the metal compound (B), and wherein a molar ratio of the metal compound B) to the organosilicon compound (A) as metal compound (B)/organosilicon compound (A) is not less than 18 and not more than 48.

Claims

1. A water/oil-repellent coating composition comprising an organosilicon compound (A) and a metal compound (B), wherein at least one first hydrocarbon chain-containing group and at least one hydrolyzable group are bonded to a silicon atom in the organosilicon compound (A), wherein at least one hydrolyzable group is bonded to a metal atom in the metal compound (B), wherein a second hydrocarbon chain-containing group having a length shorter than the length of the first hydrocarbon chain-containing group may be bonded to the metal atom in the metal compound (B), and wherein a molar ratio of the metal compound (B) to the organosilicon compound (A) as metal compound (B)/organosilicon compound (A) is not less than 18 and not more than 48.

2. The water/oil-repellent coating composition according to claim 1, wherein the molar ratio of the metal compound (B) to the organosilicon compound (A) as metal compound (B)/organosilicon compound (A) is not less than 18 and not more than 36.

3. The water/oil-repellent coating composition according to claim 1, further comprising a solvent (C).

4. The water/oil-repellent coating composition according to claim 3, wherein the solvent (C) includes an alcohol-based solvent.

5. The water/oil-repellent coating composition according to claim 1, wherein the organosilicon compound (A) is represented by formula (I) below: ##STR00013## wherein R.sup.a represents the first hydrocarbon group, each of A.sup.a1 independently represents a hydrolyzable group, Z.sup.a1 represents the first hydrocarbon chain-containing group, the second hydrocarbon chain-containing group having a length shorter than a length of the first hydrocarbon chain-containing group, or a hydrolyzable group, R.sup.a and Z.sup.a1 may be the same or different when Z.sup.a1 is the first hydrocarbon chain-containing group, Z.sup.a1 and A.sup.a1 may be the same or different when Z.sup.a1 is the hydrolyzable group, and R.sup.a and Z.sup.a1 may be the same or different when the water/oil-repellent coating composition comprises a plural number of formulae (I).

6. The water/oil-repellent coating composition according to claim 1, wherein the metal compound (B) is represented by formula (II) below:
[Chemical Formula 2]
M(R.sup.b1)(A.sup.b1).sub.m   (II) wherein R.sup.b1 represents the second hydrocarbon group or the hydrolyzable group, each of A.sup.b1 independently represents a hydrolyzable group, M represents Al, Fe, In, Ge, Hf, Si, Ti, Sn, Zr or Ta, and m represents an integer of 1 to 4 according to a kind of metal atom.

7. The water/oil-repellent coating composition according to claim 6, wherein R.sup.b1 and A.sup.b1 represent the same group in the formula (II).

8. The water/oil-repellent coating composition according to claim 6, wherein M represents Si in the formula (II).

9. The water/oil-repellent coating composition according to claim 4, wherein the metal compound (B) is represented by formula (II) below:
[Chemical Formula 2]
M(R.sup.b1)(A.sup.b1).sub.m wherein R.sup.b1 represents the second hydrocarbon group or the hydrolyzable group, each of A.sup.b1 independently represents a hydrolyzable group, M represents Al, Fe, In, Ge, Hf, Si, Ti, Sn, Zr or Ta, and m represents an integer of 1 to 4 according to a kind of metal atom.

10. The water/oil-repellent coating composition according to claim 9, wherein R.sup.b1 and A.sup.b1 represent the same group in the formula (II).

11. The water/oil-repellent coating composition according to claim 10, wherein M represents Si in the formula (II).

Description

EXAMPLES

[0158] The present invention is hereinafter described in more detail in the following by way of Examples, however, the present invention is not limited to the following Examples, and modifications which do not depart from the spirit and scope of the present invention are allowed and embraced within the technical scope of the present invention. Hereinafter, “part” and “%” mean “part by mass” and “% by mass”, respectively, unless otherwise noted.

[0159] Measurement methods used in examples of the present invention are as follows.

[0160] Measurement of liquid droplet slide behavior

[0161] A substrate provided with a coating film by coating the substrate with a water/oil-repellent coating composition was inclined at 32°, 20 μL of water was dropped onto the substrate, and the movement speed of the liquid droplet was measured. Specifically, a liquid droplet was dropped onto the coating film (position (1)). A location (position (2)) to which the liquid droplet slid down by 0.9 cm from the position (1) was defined as a starting point, and the time required for movement to a location (position (3)) to which the liquid droplet slid down by further 3 cm from the starting point was measured. The movement distance (3 cm) between the position (2) and the position (3) was divided by the time (seconds) required for sliding-down from the position (2) to the position (3), thereby determining the movement speed of the liquid droplet.

[0162] Measurement of abrasion resistance

[0163] A steel wool tester (manufactured by Daiei Seiki Co., Ltd.) was used. An eraser (MONO ONE DUST CATCH manufactured by Tombow Pencil Co., Ltd.) was brought into contact with the coating film under a load of 500 g, an abrasion test was conducted at a rate of 40 r/m in, and the number of abrasion times until the contact angle was −15° or less with respect to the initial contact angle was counted. The maximum number of abrasion times is set to 1500, and a sample with a contact angle of −15° or less even after 1500 times is evaluated as having abrasion resistance (O).

[0164] Measurement of thickness

[0165] The thickness of the coating film was measured using a non-contact-type surface shape measuring instrument (VertScan manufactured by Ryoka Systems Inc.).

[0166] Measurement of contact angle

[0167] The contact angle of a coating film surface to water was measured by a liquid droplet method (liquid amount: 3.0 μL) using a contact angle meter (DM 700 manufactured by Kyowa Interface Science Co., LTD.).

Example 1

[0168] Eighty-four parts of ethanol as a solvent (C) and 60 parts of hydrochloric acid (0.01 mol/L aqueous solution) as a catalyst were mixed with 2.8 parts (0.01 parts by mol) of octyltriethoxysilane as an organosilicon compound (A) and 41.7 parts (0.20 parts by mol) of tetraethyl orthosilicate (tetraethoxysilane) as a metal compound (B), and the mixture was stirred at room temperature for 24 hours to obtain a water/oil-repellent coating composition. The obtained water/oil-repellent coating composition was applied onto a glass substrate (“EAGLE XG” manufactured by Corning Incorporated) by spin coating under the condition of a rotation number of 3000 rpm and 20 sec using a spin coater manufactured by MIKASA Corporation, and then dried to obtain a coating film.

Examples 2 to 4 and Comparative Examples 1 to 3

[0169] A coating film was obtained in the same procedure as in Example 1 except that the kinds and use amounts of the organosilicon compound (A), the metal compound (B) and the solvent (C) were as shown in Table 1.

[0170] The contact angle to water, and the thickness, the abrasion resistance and the liquid droplet slide behavior for each of the obtained coating films are shown in Table 1.

TABLE-US-00001 Comparative Examples Examples 1 2 3 4 1 2 3 Film Component Organosilicon Octyltriethoxysilane Parts by mol 0.01 0.01 0.01 0.01 production compound (A) (276.49 g/mol) Parts 2.8 2.8 2.8 2.8 Decyltriethoxysilane Parts by mol 0.01 0.01 0.01 (304.54 g/mol) Parts 3.0 3.0 3.0 Metal Tetraethoxysilane Parts by mol 0.20 0.48 0.187 0.354 0.04 0.08 0.04 compound (B) (208.33 g/mol) Parts 41.7 100.0 39.0 73.7 8.3 16.7 9.2 Solvent (C) Ethanol Parts 84 193.6 81.4 146.2 22.0 37.9 25 Catalyst 0.01 mol/L Parts 60.0 137.0 55.0 102.0 13.5 24.0 15 Hydrochloric acid Physical Contact angle (water) ° 106.2 107.0 109.1 108.8 105.2 106.8 108.2 property Thickness nm 16.5 200 280 205.0 316 225 327 Abrasion resistance Times ∘ ∘ ∘ ∘ <100 300 <100 Slide behavior (movement speed of the liquid droplet. cm/sec 23.1 21.2 23.4 22.2 24.6 23.1 14.17 water 20 μm)

[0171] The results described above show that a coating film attaining both water/oil repellency and abrasion resistance can be obtained using the water/oil-repellent coating composition of the present invention.

INDUSTRIAL APPLICABILITY

[0172] Using the water/oil-repellent coating composition of the present invention, the water/oil-repellent coating composition the coating film attaining both water/oil repellency and abrasion resistance is obtained, and is useful for fields in display devices such as touch panel displays, optical elements, semiconductor elements, building materials, automobile components, nanoimprint techniques, solar cell members and so on.