Stainproof optical member and manufacture thereof

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention mainly relates to an optical member having excellent antifouling property, water-repellent and oil-repellent property, and a method for manufacturing the same. More specifically, it is represented by a display-type touch panel switch, a face plate of a copying machine, a frennel plate for an overhead projector, a glass for a display, an optical filter for a display, a halogen lamp, a mercury lamp, a sodium lamp, a light bulb, a chandelier, and various lenses. It relates to a high-performance antifouling optical member having a high water-repellent, oil-repellent and antifouling effect.

【0002】

[Conventional technology]

Conventionally, glass and plastic surfaces such as display-type touch panel switches, copier face plates, OHP frennel plates, halogen lamps, mercury lamps, sodium lamps, light bulbs, chandeliers, and lenses are sweaty or dirty when touched by human hands. There was a problem that it became dirty and the performance deteriorated significantly. In addition, there is a problem that it is difficult to remove stains on lenses and the like when water adheres to them and dries them (called a water-burning phenomenon).

【0003】

In order to solve this problem, a technique is known in which an oligomer such as γ-glycidoxypropyltrimethoxysilane and / or fine particles such as silica and antimony are added thereto, coated on the surface of a substrate, cured, and coated thinly. ing. As another example, it has been proposed to treat the substrate surface with a silazane compound.

【0004】

[Problems to be Solved by the Invention]

However, the known technique for preventing stains on the glass surface and the plastic surface has a problem that the stain resistance and the water and oil repellency are not so excellent, and there is a problem in durability.

【0005】

The present invention is a high-performance optical member having a high antifouling effect that does not adhere to dirt or is easily removed even if dirt adheres in order to solve the above-mentioned problems of the prior art, and also has excellent durability. Provided are an optical member having a coating thin film and a method for manufacturing the same.

【0006】

[Means for solving problems]

In order to achieve the above object, the antifouling optical member of the present invention is an optical member having a thin film formed on its surface, and the thin film has a thickness of carbon fluoride that does not impair the original optical characteristics of the optical member. Antifouling optics comprising a chemically adsorbed monomolecular film containing a group, the thin film being formed by a chemical bond with a member, and the molecules constituting the thin film being formed in an oriented state. Element.

【0007】

In the above configuration, it is preferable that a chemically adsorbed monolayer containing a fluorocarbon group is formed on the surface at least via a siloxane-based monolayer.

【0008】

Further, in the above configuration, the base material of the optical member is made of glass or plastic material, and the optical member includes a display type touch panel switch, a face plate of a copying machine, a frennel plate for an overhead projector, glass for display, and an optical filter for display. It is represented by halogen lamps, mercury lamps, sodium lamps, light bulbs, chandeliers, and optical lenses.

【0009】

Next, in the first manufacturing method of the present invention, after cleaning the base material of the optical member, a chlorosilyl group (-SiCl) is formed at one end._nX_3-nThe base material is brought into contact with an organic solvent in which a chlorosilane-based surfactant having a group (n = 1, 2, 3, X is a functional group) and having a fluorocarbon group at the other end is dissolved, and the base material is originally formed. It is characterized in that a chemically adsorbed monomolecular film made of the active agent in an oriented state is formed over the entire surface of the base material with a thickness that does not impair the optical properties of the above.

【0010】

Next, in the second production method of the present invention, after cleaning the base material of the optical member, the base material is brought into contact with a non-aqueous solvent mixed with a silyl compound containing a plurality of chlor groups, and the hydroxyl groups on the surface of the base material and the chlor are brought into contact with each other. A step of reacting with a group to precipitate the silyl compound on the surface of the base material, and washing and removing the unreacted silyl compound remaining on the base material using a non-aqueous organic solvent, and then reacting with water to obtain the above. A step of forming a monomolecular film composed of a substance containing a plurality of silanol groups on a base material, and a chlorosilyl group (SiCl) at one end._nX_3-nA chlorosilane-based surfactant having a group (n = 1, 2, 3, X is a functional group) and having a linear fluorocarbon group at the other end is chemically adsorbed on the silanol-based monomolecular film on the substrate. It is characterized by including a step of accumulating a single molecule adsorption film.

【0011】

In the second production method, SiCl is used as a silyl compound containing a plurality of chloro groups.₄, SiHCl₃, SiH₂Cl₂, Cl- (SiCl₂O)_n-SiCl₃The method for manufacturing an antifouling optical member according to claim 5, wherein (n is an integer).

【0012】

Further, in both of the above-mentioned production methods, CF is used as a chlorosilane-based surfactant having a chlorosilyl group at one end and a linear fluorocarbon group at the other end.₃-(CF₂)_n-R-SiX_pCl_3-p(n is 0 or an integer, R is an alkylene group, an ethylene group, an acetylene group (same as an ethynylene group), SiO-, or a substituent containing an oxygen atom may or may not be used, and X is an H or alkyl group substituent. , P is preferably 0 or 1 or 2).

【0013】

[Action]

According to the configuration of the present invention, it is an optical member in which a thin film is formed on the surface of a base material, the thin film contains at least a chemically adsorbed monomolecular film containing a fluorocarbon group, and the thin film is chemically with the base material. Since the molecules are formed in an aligned state (orientation state) by bonding, it is possible to obtain a high-performance optical member having a high antifouling effect so that dirt does not adhere or even if it adheres, it is easily removed. It is also highly durable. Further, since fluorine is present on the outermost surface of the thin film, the slipperiness of the surface of the optical member is improved and scratches are less likely to occur.

【0014】

Further, in the present invention, since a fluorocarbon-based monomolecular film having an extremely thin nanometer-level film thickness (thin film) is formed on the surface of the optical member, the original functions such as light transmission of the optical member are not impaired at all. Further, since this film is an oriented fluorocarbon-based monolayer, it is also excellent in water and oil repellency, and it is possible to enhance the antifouling effect on the surface. Therefore, it is possible to obtain a high-performance optical member having a high antifouling effect against human sweat and dirt.

【0015】

Further, the above-mentioned manufacturing method of the present invention can reasonably and efficiently manufacture the thin film of the present invention.

【0016】

[Example]

As an example of glass used in the above-mentioned optical member applications, since it is an oxide, it contains a hydroxyl group on its surface. Therefore, a chlorsilyl group (SiCl) at one end_nX_3-nA molecule containing a linear carbon chain having a group (n = 1, 2, 3, X is a functional group), for example, a chlorosilane-based surfactant containing a fluorocarbon group and a chlorosilyl group, is brought into contact with a non-aqueous solvent mixed. A non-aqueous solvent in which a hydroxyl group on the glass surface is reacted with a chlorosilyl group of a substance containing a plurality of chlorosilyl groups to precipitate a monomolecular film composed of the substance on the glass surface, or a substance containing a plurality of chlorosilyl groups is mixed. The step of reacting the hydroxyl group on the glass surface with the chlorosilyl group of a substance containing a plurality of the chlorosilyl groups to precipitate the substance on the glass surface, and the excess remaining on the glass surface using a non-aqueous organic solvent. It contains a step of washing and removing a substance containing a plurality of chlorosilyl groups to form a siloxane-based monomolecular film composed of a substance containing a plurality of chlorosilyl groups on the glass, and a linear carbon chain having a chlorosilyl group at one end. A fluorocarbon-based chemically adsorbed single-molecule cumulative film can be formed on the glass surface by a step of chemically adsorbing a silane-based surfactant on glass and accumulating a single-molecule adsorption film.

【0017】

Further, if the base material does not have an oxide film on the surface such as a plastic base material, the surface is previously treated in a plasma atmosphere containing oxygen at 100 W for about 20 minutes to make it hydrophilic, that is, a hydroxyl group is formed on the surface. Should be introduced.

【0018】

Below, as the optical base material according to the present invention, the antifouling effect represented by a display type touch panel switch, a face plate of a copying machine, an OHP frennel plate, a halogen lamp, a mercury lamp, a sodium lamp, a light bulb, a chandelier, various lenses, etc. There are high-performance glass and plastic, but as typical examples, a cathode ray tube (CRT) display type touch panel switch and an OHP frennel plate will be explained in order. In the following examples,% means% by weight unless otherwise specified.

【0019】

Example 1 First, prepare a CRT for a glass display type touch panel switch that has been processed (it may be a face plate before assembly), wash it with an organic solvent, and then mix it with a substance containing a fluorocarbon group and a chlorosilyl group. Solvent, eg CF₃(CF₂)₇(CH₂)₂SiCl₃To prepare 80% n-hexadecane (toluene, xylene, dicyclohexyl may be used), 12% carbon tetrachloride, and 8% chloroform solution dissolved at a concentration of about 1%, and immerse the CRT for about 2 hours, the CRT Since the surface of the CRT contains a large number of hydroxyl groups, the SiCl group of the substance containing a fluorocarbon group and a chloroform silyl group reacts with the hydroxyl group to cause a dehydroxylation reaction, which spreads over the entire surface of the CRT and CF.₃(CF₂)₇(CH₂)₂Si (O-)₃The bond was formed, and the fluorine-containing monolayer 2 could be formed with a film thickness of about 15 angstroms (1.5 nm) in a state of being chemically bonded to the surface of the CRT (Fig. 1). Since the monolayer was chemically bonded very strongly, it did not peel off at all.

【0020】

We tried to use this CRT in practice, but we were able to significantly reduce the adhesion of filth compared to the untreated one, and even if it did, we could easily remove oils and fats such as fingerprints by rubbing with a tissue. .. Also, at this time, no scratches were made.

【0021】

Example 2 In the case of tempered glass that is hydrophilic but contains a small proportion of hydroxyl groups, such as OHP Fresnel plates, a substance containing a plurality of trichlorosilyl groups (for example, SiCl).₄, Or SiHCl₃, SiH₂Cl₂, Cl- (SiCl₂O)_n-SiCl₃(n is an integer). Especially SiCl₄If you use, the molecule is small and the activity against hydroxyl groups is large, so the effect of uniformly hydrophilizing the plate surface is large). Since some hydrophilic OH groups 12 are present on the plate surface 11 (Fig. 2), a desolvation reaction occurs on the surface to form a chlorosilane monomolecular film of a substance containing a plurality of trichlorosilyl groups.

【0022】

For example, SiCl as a substance containing a plurality of trichlorosilyl groups₄Since a small amount of hydrophilic OH groups are exposed on the plate surface 11, a dehydrochloric acid reaction occurs on the surface, and molecules are attached to the surface via a -SiO- bond as shown in [Chemical formula 1] below. It is fixed.

【0023】

[Chemical 1]

<img file="JP2500152B2_D0001.tif" />After that, when it was washed with a non-aqueous solvent such as chloroform and then with water, SiCl which did not react with the vessel was obtained.₄Molecules are removed, and a siloxane monolayer 13 such as the one shown below [Chemical Formula 2] is obtained on the plate surface (Fig. 3).

【0024】

[Chemical 2]

<img file="JP2500152B2_D0002.tif" />Since the monolayer 13 formed at this time is completely bonded to the plate via a chemical bond of -SiO-, it will not be peeled off at all. In addition, the obtained monolayer has many SiOH bonds on its surface. About three times as many hydroxyl groups as the initial hydroxyl group are produced.

【0025】

Therefore, a non-aqueous solvent in which a substance containing a fluorocarbon group and a chlorosilyl group is mixed, for example, CF₃(CF₂)₇(CH₂)₂SiCl₃Prepare an 80% n-hexadecane, 12% carbon tetrachloride, and 8% chloroform solution dissolved at a concentration of about 10%, and place a plate with a monolayer having many SiOH bonds on the surface for 1 hour. CF on the plate surface when immersed to some extent₃(CF₂)₇(CH₂)₂Si (O-)₃The bond was formed, and the fluorine-containing monolayer 14 was chemically bonded to the underlying siloxane monolayer, and could be formed with a film thickness of about 15 angstroms (1.5 nm) over the entire surface of the plate (Fig. 4). The monolayer was not peeled at all even when the peeling test was performed.

【0026】

Furthermore, in the above embodiment, CF is used as a fluorocarbon-based surfactant.₃(CF₂)₇(CH₂)₂SiCl₃However, if an ethylene group or an ethynylene group is added or incorporated into the alkyl chain portion, it can be crosslinked by electron beam irradiation of about 5 megarads after the formation of the monomolecular film, so that the hardness of the monomolecular film can be further improved. It is possible.

【0027】

In addition to the above as fluorocarbon-based surfactants, CF₃CH₂O (CH₂)₁₅SiCl₃, CF₃(CH₂)₂Si (CH₃)₂(CH₂)₁₅SiCl₃, F (CF)₂)₈(CH₂)₂Si (CH₃)₂(CH₂)₉SiCl₃, CF₃COO (CH)₂)₁₅SiCl₃, CF₃(CF₂)₅(CH₂)₂SiCl₃Etc. can be used.

【0028】

As described above, according to the embodiment of the present invention, since a fluorocarbon-based monolayer having an extremely thin nanometer-level film thickness is formed on the surface of the base material, the original optical characteristics of the optical base material are not impaired at all. Absent. In addition, the fluorocarbon-based monolayer is also excellent in water and oil repellency, and it is possible to enhance the antifouling effect on the surface. Therefore, it is possible to provide a high-performance optical member having an extremely high antifouling effect against human sweat and dirt. Further, this has a great effect that the number of washings can be significantly reduced.

【0029】

[Effect of the invention]

As described above, according to the present invention, since the fluorocarbon-based monolayer having an extremely thin nanometer-level film thickness is oriented and formed on the surface of the optical base material, the original optical characteristics of the optical member are not impaired. It is possible to enhance the antifouling effect on the surface. In addition, this fluorocarbon-based monolayer is also excellent in water and oil repellency. Therefore, it is possible to provide a high-performance optical member having an extremely high antifouling effect. Furthermore, this has a great effect of significantly reducing maintenance.

[Simple explanation of drawings]

[Figure 1]

It is sectional drawing which enlarged the surface of the CRT of this invention to a molecular level.

[Figure 2]

It is sectional drawing before the processing process which expanded the surface of the Fresnel plate of OHP to the molecular level in order to explain the 2nd Example of the glass of this invention.

[Fig. 3]

It is sectional drawing in the process process which expanded the surface of the Fresnel plate of OHP to the molecular level in order to explain the 2nd Example of the glass of this invention.

[Fig. 4]

It is sectional drawing after the treatment which expanded the surface of the Fresnel plate of OHP to the molecular level in order to explain the 2nd Example of the glass of this invention.

[Explanation of symbols]

1 CRT surface 11 OHP plate surface 2,14 Monolayer 12 hydroxyl groups 13 Siloxane monolayer