Water repellent surface treatment for plastic and coated plastic substrates

• US 5,523,162 A
• Filed: 12/27/1994
• Issued: 06/04/1996
• Est. Priority Date: 04/03/1990
• Status: Expired due to Term

• Current Assignee: PPG Industries Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Incorporated (Nouryon BV)
• Inventors: Goodwin, George B., Marietti, Gary J., Franz, Helmut
• Primary Examiner(s): Makarani, D. S.
• Assistant Examiner(s): LE, HOA T
• Application Number:
  US08/363,804
• Time in Patent Office: 525 Days
• Field of Search: 428/421, 428/422, 428/447, 428/446, 428/429, 427/402, 427/407.1-412.1, 427/444, 427/384, 427/387, 427/165, 427/389.7, 427/397.7
• US Class Current: 428/421
• CPC Class Codes: C03C 17/009 Mixtures of organic and inorganic materials, e.g. ormosils and ormocers
• CPC Class Codes: C03C 17/30 with silicon-containing compounds
• CPC Class Codes: C03C 17/328 Polyolefins
• CPC Class Codes: C09K 3/18 for application to surfaces to minimize adherence of ice, mist or water thereto rendering particulate materials free flowing, in general, e.g. making them hydrophobic B01J2/30; Thawing or antifreeze materials for application to surfaces used in liquids for heat-transfer, heat-exchange or heat-storage or for the production of heat or cold other than by combustion, e.g. radiator liquids, C09K5/00
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31544 Addition polymer is perhalogenated
• CPC Class Codes: Y10T 428/31612 As silicone, silane or siloxane
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

A method and article are disclosed wherein a plastic substrate is provided with a more durable non-wetting surface by deposition of a silica primer layer prior to treatment with perfluoroalkylalkylsilane and optionally a fluorinated olefin telomer on the surface which comprises the silica primer layer.

Claims

1. An article comprising a plastic substrate the surface of which is coated with

a. a silica primer layer;

and

b. a perfluoroalkylalkylsilane bonded to said silica primer layer wherein said perfluoroalkylalkylsilane is selected from compounds having the general formula R_m (R'"'"'_n)SiX_4-n-m, wherein R is a perfluoroalkylalkyl radical, R'"'"' is selected from the group consisting of vinyl and alkyl radicals, m is one, n is zero or one, m+n is less than 4, and X is a radical selected from the group consisting of halogen, alkoxy and acyl radicals.

2. An article according to claim 1, wherein said perfluoroalkylalkyl radical comprises a perfluoroalkyl moiety of the formulae CF₃ to C₃₀ F₆₁.

3. An article according to claim 2, wherein said perfluoroalkyl moiety comprises C₆ F₁₃ to C₁₈ F₃₇.

4. An article according to claim 3, wherein said perfluoroalkyl moiety comprises C₈ F₁₇ to C₁₂ F₂₅.

5. An article according to claim 1, wherein R'"'"' is selected from the group consisting of methyl, ethyl, vinyl and propyl.

6. An article according to claim 1, wherein X is selected from the group consisting of chloro, iodo, bromo, methoxy, ethoxy and acetoxy.

7. An article according to claim 1, wherein said substrate is acrylic, and said perfluoroalkylalkylsilane is selected from the group consisting of perfluoroalkylethyltrichlorosilane, perfluoroalkylethyltriacetoxysilane, perfluoroalkylethyltrimethoxysilane, perfluoroalkylethyldichloro(ethyl)silane and perfluoroalkylethyldiethoxy(methyl)silane.

8. An article according to claim 7, wherein said perfluoroalkylalkylsilane is combined with a fluorinated olefin telomer.

9. An article according to claim 8, wherein said fluorinated olefin is a telomer comprises C_m F_2m+1 CH═

CH₂, wherein m is from 1 to 30.

10. A method of producing a non-wetting surface on a plastic substrate comprising the steps of:

a. depositing a silica primer layer on a surface of said substrate; and

b. depositing on said silica primer layer a composition comprising a perfluoroalkylalkylsilane wherein said perfluoroalkylalkylsilane is selected from compounds having the general formula R_m (R'"'"'_n)SiX_4-n-m, wherein R is a perfluoroalkylalkyl radical, R'"'"' is selected from the group consisting of vinyl and alkyl radicals, m is one, n is zero or one, m+n is less than 4, and X is a radical selected from the group consisting of halogen, alkoxy and acyl radicals.

11. A method according to claim 10, wherein said perfluoroalkylalkyl radical comprises a perfluoroalkyl moiety of the formulae CF₃ to C₃₀ F₆₁.

12. A method according to claim 11, wherein said composition further comprises a fluorinated olefin telomer.

13. A method according to claim 12, wherein the step of depositing a silica primer layer is accomplished by applying to the substrate surface a solution of a hydrolyzable silicon-containing compound which hydrolyzes and condenses to form a silica-containing film on the substrate surface.

14. A method according to claim 13, wherein said hydrolyzable silicon-containing compound is selected from the group consisting of tetrachlorosilane, tetraacetoxysilane, hexachlorodisiloxane, and mixtures thereof.

15. A method according to claim 14, wherein said perfluoroalkylalkylsilane is selected from the group consisting of perfluoroalkylethyltrichlorosilane, perfluoroalkylethyltriacetoxysilane, perfluoroalkylethyltrimethoxysilane, perfluoroalkylethyldichloro(methyl)silane and perfluoroalkylethyldiethoxy(methyl)silane, and wherein said fluorinated olefin is a telomer comprising C_m F_2m+1 CH═

CH₂, wherein m is from 1 to 30.

16. A method according to claim 14, wherein R'"'"' is selected from the group consisting of methyl, ethyl, vinyl and propyl.

17. A method according to claim 16, wherein X is selected from the group consisting of chloro, iodo, bromo, methoxy, ethoxy and acetoxy.

18. A method according to claim 15, wherein said telomer comprises C_m F_2m+1 CH═

CH₂ wherein m is from 4 to 10.