JP2008105887A - Super water-repellent glass substrate and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a super water-repellent glass substrate; and to provide a method for manufacturing the super water-repellent glass substrate, which comprises forming fine unevenness on the surface of a glass substrate by finely processing the surface of the glass substrate and then forming a coating, formed from a condensate of a silane compound, on the resulting surface of the glass substrate. <P>SOLUTION: The super water-repellent glass substrate is obtained by treating a glass substrate with an alkali solution to form a nanosized fine structure on the surface of the glass substrate and then directly providing a coating of a water-repellent agent on the resulting surface of the glass substrate. The method for manufacturing the super water-repellent glass substrate is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a super water-repellent glass substrate and a method for producing the same.

In the conventional technique, nanostructure control by etching is realized only with plastic (see Non-Patent Document 1), and nanostructure control by etching has not been reported for glass that is an inorganic substance.
Plastics that are organic compounds have low heat resistance, structural strength, and the like, and a simple nanostructure fabrication process using a glass material that is excellent in heat resistance, high strength, and inexpensive has been required.
In the conventional technique, after aluminum oxide is produced on a substrate by a sol-gel method, a petal-like structure is produced by hot water treatment, and this is coated with a silane compound to produce a super-water-repellent (contact angle) of 165 (See Patent Document 1).
JP-A-9-202649 Erbil HY, Demirel AL, Avci Y, et al. Transformation of a simple plastic into asuperhydrophobic surface SCIENCE299 (5611): 1377-1380 FEB 28 2003

  The present invention produces a super-water-repellent glass substrate by finely processing the surface of the glass substrate to create fine irregularities on the glass surface and forming a film of the silane compound condensate thereon.

In order to achieve the above-mentioned object, the present inventor continued earnest research and treated the glass substrate with alkali to create fine irregularities on the glass surface and to form a coating with a special silane compound condensate thereon. It has been found that a super water-repellent glass substrate can be produced by making it.
That is, the present invention is a super water-repellent glass substrate in which a coating of a water repellent is directly provided on the surface of a glass substrate having a nano-sized microstructure obtained by treating the glass substrate with an alkaline solution.
Further, in the present invention, as a water repellent, a condensate of hexyltrimethoxysilane containing no fluorine, or heptadecafluorodecyltrimethoxysilane, tridecafluorooctylmethoxysilane, 2- (perfluorooctyl) containing fluorine 1) selected from the group consisting of silane coupling agents such as ethyl) trichlorosilane, polymers having long-chain perfluoroalkyl groups such as perfluorolauric acid, poly (perfluorodecylethyl acrylate), and vinyl-terminated polydimethylsiloxanes. Seeds can be used.
Furthermore, in the present invention, the alkaline solution can be adjusted to pH 8 or higher.
In the present invention, the glass substrate is immersed in an alkaline aqueous solution having a pH of 8 or higher, held at a temperature of 90 to 250 ° C. for 0.5 to 48 hours, then taken out, washed and dried, and hexyltrimethoxy containing no fluorine. This is a method for producing a super water-repellent glass substrate obtained by applying and curing heptadecafluorodecyltrimethoxysilane containing silane or fluorine.
In the production method of the present invention, one alkali selected from the group consisting of LiOH, NaOH, KOH, MnOOH, NH ₄ OH, and urea can be used.
Further, in the production method of the present invention, it is desirable that the alkaline aqueous solution is NaOH having a pH of 9 to 11, the temperature of the alkaline aqueous solution is 95 to 100 ° C., and the immersion time is 1 to 24 hours.

  All of the super water-repellent glass substrates of the present invention exhibit super water repellency with a contact angle of 150 ° or more, and a super water-repellent glass substrate can be easily produced by a relatively simple manufacturing method.

The glass of the glass substrate used in the present invention may be anything other than quartz glass, and various commercially available glass plates can be used.
The alkali used in the present invention is one selected from the group consisting of LiOH, NaOH and KOH, and NaOH is preferably used.
As for the concentration of the alkali, the pH is 8 or more, preferably pH 8.5 to 13, more preferably pH 9 to 11.
The temperature of the alkaline aqueous solution in the present invention is 90 to 250 ° C, and preferably 90 to 120 ° C.
Moreover, although the immersion time in this invention changes also with temperature, it is 0.5 to 48 hours normally, Preferably it is 1 to 24 hours.

The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The glass substrate was immersed in 1M NaOH aqueous solution and kept at 100-200 ° C. for several hours, then taken out, washed and dried.
This was coated with hexyltrimethoxysilane containing no fluorine or heptadecafluorodecyltrimethoxysilane containing fluorine.
For coating, silane was dissolved in hexane, left at 60 ° C. for 24 hours, taken out, and dried at room temperature.
Fig. 1 shows an SEM photograph of a glass substrate that was treated in a 1M NaOH aqueous solution for 5 hours at 100 ° C. Nanoscale irregularities can be confirmed.
FIG. 2 is a super-water-repellent photograph in which hexyltrimethoxysilane is coated on a substrate that has been treated at 100 ° C. for 5 hours in a 1M NaOH aqueous solution.
Fig. 3 is a photograph of super-water-repellent material in which heptadecafluorodecyltrimethoxysilane was coated on a substrate that had been treated at 100 ° C for 5 hours in 1M NaOH aqueous solution. It can be seen that both show super water repellency with a contact angle of 150 ° or more.
Fig. 4 is a photograph of water repellency of a glass substrate (comparative example) in which heptadecafluorodecyltrimethoxysilane is coated on a smooth glass substrate. The contact angle is about 113 degrees, indicating super-water repellency of 150 degrees or more. Absent.
Figure 5 shows a glass treated at 100 ° C for 5 hours in 1M NaOH aqueous solution. It turns out that favorable transparency is acquired.

  Nanoscale irregularities can be confirmed. FIG. 6 is a super water-repellent photograph in which heptadecafluorodecyltrimethoxysilane is coated on a substrate that has been treated at 200 ° C. for 24 hours in an aqueous solution with a pH controlled to 9.14 using NaOH. It can be seen that it exhibits super water repellency of 150 ° or more. Fig. 7 is a photograph of oil repellency in which hexadecane, an oil, is dropped onto a glass coated with heptadecafluorodecyltrimethoxysilane on glass treated at 200 ° C for 24 hours in an aqueous solution with pH controlled to 9.14 using NaOH. It is. It can be seen that the contact angle is about 105 degrees, which is an oil repellent film. FIG. 8 shows a glass substrate treated at 200 ° C. for 2 hours in an aqueous solution whose pH is controlled to 9.14 using NaOH. It turns out that favorable transparency is acquired.

  FIG. 9 is a super water-repellent photograph in which heptadecafluorodecyltrimethoxysilane is coated on a glass substrate treated at 200 ° C. for 24 hours in an aqueous solution whose pH is controlled to 9.14 using NaOH. It can be seen that it exhibits super water repellency of 150 ° or more. FIG. 10 shows an oil-repellent solution in which hexadecane, which is an oil, is dropped on a film coated with heptadecafluorodecyltrimethoxysilane on a glass substrate treated at 200 ° C. for 24 hours in an aqueous solution whose pH is controlled to 9.14 using NaOH. It is a photograph. It can be seen that the contact angle is about 145 degrees, which is a very good oil repellent film.

  The super water-repellent glass substrate of the present invention is suitable for mass production, and can be expected to be used for window glass of automobiles and buildings.

SEM photo of glass substrate treated at 100 ° C for 5h in 1M NaOH aqueous solution A super water-repellent photo of hexyltrimethoxysilane coated on a glass substrate treated at 100 ° C for 5 hours in 1M NaOH aqueous solution A super-water-repellent photograph in which heptadecafluorodecyltrimethoxysilane is coated on a glass substrate that has been treated at 100 ° C for 5 hours in 1M NaOH aqueous solution. Water-repellent photo of heptadecafluorodecyltrimethoxysilane coated on a smooth glass substrate Photograph of glass treated at 100 ° C for 5 hours in 1M NaOH aqueous solution A super-water-repellent photograph in which heptadecafluorodecyltrimethoxysilane is coated on a glass substrate that has been treated at 200 ° C for 2 hours in an aqueous solution with a pH controlled to 9.14 using NaOH. A photo of oil repellency in which hexadecane, an oil, was dropped onto a glass substrate that had been treated at 200 ° C for 2 hours in an aqueous solution with a pH controlled at 9.14 using NaOH and coated with heptadecafluorodecyltrimethoxysilane. Photo of a glass substrate treated at 200 ° C for 2 hours in an aqueous solution with a pH controlled to 9.14 using NaOH A super-water-repellent photograph in which heptadecafluorodecyltrimethoxysilane is coated on a glass substrate that has been treated at 200 ° C for 24 hours in an aqueous solution whose pH is controlled to 9.14 using NaOH. A photo of oil repellency in which hexadecane, an oil, is dropped onto a glass substrate coated with heptadecafluorodecyltrimethoxysilane on a glass substrate that has been treated at 200 ° C for 24 hours in an aqueous solution with a pH controlled to 9.14 using NaOH.

Claims (6)

  A super water-repellent glass substrate in which a water repellent film is directly provided on the surface of a glass substrate having a nano-sized fine structure obtained by treating the glass substrate with an alkaline solution.   The water repellent is a condensate of hexyltrimethoxysilane that does not contain fluorine, or heptadecafluorodecyltrimethoxysilane, tridecafluorooctylmethoxysilane, or 2- (perfluorooctyl) ethyl] trichlorosilane containing fluorine. The silane coupling agent, perfluorolauric acid, poly (perfluorodecylethyl acrylate) and other polymers having a long-chain perfluoroalkyl group, and one kind selected from the group consisting of vinyl-terminated polydimethylsiloxanes. The super water-repellent glass substrate described.   The super-water-repellent glass substrate according to claim 1 or 2, wherein the alkaline solution has a pH of 8 or more (for example, a basicity of pH 14 or more is acceptable, such as 1M NaOH).   A glass substrate is immersed in an alkaline aqueous solution of pH 8 or higher, held at a temperature of 90 to 250 ° C. for 0.5 to 48 hours, then taken out, washed and dried, and fluorine-free hexyltrimethoxysilane or fluorine-containing heptadeca A method for producing a super water-repellent glass substrate obtained by coating and curing fluorodecyltrimethoxysilane.   The method for producing a super water-repellent glass substrate according to claim 4, wherein the alkali is one selected from the group consisting of LiOH, NaOH, KOH, MnOOH, NH4OH, and urea.   The production of a super water-repellent glass substrate according to claim 4 or 5, wherein the alkaline aqueous solution is NaOH having a pH of 9 to 11, the temperature of the alkaline aqueous solution is 95 to 100 ° C, and the immersion time is 1 to 24 hours. Method.

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