JP2561395B2 - Optical member having water-repellent thin film and method for manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical member having a water-repellent thin film having excellent durability.

[0002]

2. Description of the Related Art A vapor deposition film which is an antireflection film formed on an optical member such as a lens is generally formed of an inorganic oxide such as ZrO ₂ or SiO ₂ . Therefore, stains such as sweat and fingerprints are easily attached, and it is difficult to remove these stains. As a method for solving these problems, for example, in JP-A-60-212470, a water-repellent film is formed by dipping or coating and curing a resin (optical substrate) in a dilute solution of perfluoroalkyl group-substituted ammonium silane. A method of doing so is disclosed. In addition, JP-A-62-14
Japanese Patent No. 8902 discloses a method of forming a thin film by dipping or coating a resin (optical substrate) in a dilute solution of perfluoroalkyl group-substituted ammonium silane.

[0003]

However, JP-A-60-212470 and JP-A-62-148902.
The water repellency of the thin film formed by the method disclosed in the publication is poor in durability, and it has a drawback that the water repellency is greatly reduced with use.

Therefore, an object of the present invention is to provide a method for forming a water-repellent thin film having excellent durability on an optical member such as a spectacle lens. A further object of the present invention is to provide an optical member having a water-repellent thin film having excellent durability.

[0005]

The present invention provides an organic compound represented by the following unit formula (I): C _p F _{2p + 1} CH ₂ CH ₂ Si (NH) _1.5 (where p is an integer of 1 or more). The present invention relates to a method for producing an optical member having a thin film, which comprises heating and evaporating a silicon compound as a solution diluted with a solvent in a vacuum, and depositing the solution on the optical substrate to form a thin film on the optical substrate.

When the water-repellent thin film of the optical member obtained by the above-mentioned manufacturing method has an antireflection film, it does not change the interference color and is excellent in durability, and the same organosilicon compound is used. In addition, the durability of the antireflection film is remarkably superior to that of the antireflection film formed by the dip method under the condition that the interference color is not changed.

Hereinafter, the present invention will be described in detail. In the organosilicon compound represented by the formula (I) used in the present invention, p is preferably 1-20, more preferably 1-10. The organosilicon compound represented by the unit formula (I) is exemplified below.

N-CF ₃ CH ₂ CH ₂ Si (NH ₂ ) ₃ n-trifluoro (1,1,2,2-tetrahydro) propylsilazane n-C ₃ F ₇ CH ₂ CH ₂ Si (NH ₂ ) ₃ n - Heputafuroro (1,1,2,2-tetrahydro) Penchirushirazan _{n-C 4 F 9 CH 2} CH 2 Si (NH 2) 3 n- Nonafuroro (1,1,2,2-tetrahydro) hexyl silazane n-C ₆ F ₁₃ CH ₂ CH ₂ Si (NH ₂ ) ₃ n-Trideofuroro (1,1,2,2-tetrahydro)
Octyl silazane _{n-C 8 F 17 CH 2} CH 2 Si (NH 2) 3 n- Heputadekafuroro (1,1,2,2-tetrahydro) Deshirushirazan

The above compounds may be used alone or in admixture of two or more.

The manufacturing method of the present invention can be carried out by using a vacuum vapor deposition apparatus generally used for coating optical members such as lenses. An example of the manufacturing method will be shown below.

The organosilicon compound (I) is heated and evaporated under vacuum to form a thin film on the optical substrate. The thickness of this thin film basically changes depending on the evaporation amount of the organosilicon compound (I). In the present invention, a thin film having good water repellency can be obtained by controlling the film thickness of the thin film on the order of angstroms. Therefore, it is preferable to adjust the evaporation amount of the organosilicon compound (I) more accurately.
Therefore, the organosilicon compound (I) is used as a solution diluted with a solvent for the purpose of more accurately adjusting this evaporation amount. As the solvent, for example, a solvent such as xylylene hexafluoride or trichloromonofluoromethane can be used after being dissolved in a fluorine-based solvent. By diluting the organosilicon compound (I), the amount of evaporation can be adjusted precisely, and as a result, the desired thin film can be easily obtained. The concentration of the organosilicon compound (I) in the solution is not particularly limited as long as the above purpose can be achieved, and can be appropriately determined depending on the type of the organosilicon compound (I) and the desired thin film.

The above organosilicon compound solution is placed in a suitable container and heated and evaporated. A particularly preferable container is a porous material, and it is possible to obtain an appropriate vapor deposition rate by impregnating this porous material with the above solution and heating. As the porous material, more specifically, it is preferable to use a sintered filter obtained by sintering a metal powder having high thermal conductivity such as copper. The mesh of the porous material has a mesh size of 40 to 200 μm, preferably 80 to 120 μm, from the viewpoint of obtaining an appropriate vapor deposition rate.

The heating temperature of the container containing the organosilicon compound (I) solution is 200 to 300 ° C., preferably 200.
It is preferable to set the temperature to 240 ° C. from the viewpoint of obtaining an appropriate vapor deposition rate.

The degree of vacuum in the vacuum vapor deposition apparatus is 10 ^-3 to 10
^-5 Torr, preferably 5 × 10 ^{-3 to} 5 × 10 ^-4 Torr is suitable for obtaining an appropriate vapor deposition rate.

The deposition rate is from 1 × 10 ⁻³ mg / cm ² seconds to
The range of 1 × 10 ⁻⁵ mg / cm ² seconds is preferable for obtaining a uniform thin film, and the vapor deposition rate in this range can be obtained by adjusting the above conditions.

The evaporated organosilicon compound (I) adheres to the optical substrate in the vacuum vapor deposition apparatus to form a thin film.

According to the method of the present invention, it is possible to freely control the refractive index and the film thickness of a thin film, which was difficult by the conventional method. That is, the strength of water repellency can be controlled by controlling the refractive index of the thin film. Further, by controlling the film thickness, it is possible to prevent the strength of water repellency and the deterioration of the antireflection property (prevention of change in interference color).

Based on the above viewpoint, the present invention provides an optical member having a water-repellent thin film having a refractive index of 1.30 to 1.37 (λ = 633 nm) and a film thickness of 1 to 50 Å. can do. With the conventional method, it was almost impossible to set both the refractive index and the film thickness in this range.

In the present invention, the optical member means not only a spectacle lens but also a camera lens, an optical filter attached to a display of a word processor, a window glass of an automobile, and the like.

The optical substrate used in the present invention includes methyl methacrylate homopolymer, methyl methacrylate and 1
Copolymer containing at least one other monomer as a monomer component, diethylene glycol bisallyl carbonate homopolymer, copolymer containing diethylene glycol bisallyl carbonate and at least one other monomer as a monomer component, sulfur-containing copolymer An optical substrate made of plastic such as a polymer, a halogen-containing copolymer, polycarbonate, polystyrene, polyvinyl chloride, unsaturated polyester, polyethylene terephthalate or polyurethane, or an optical substrate made of inorganic glass can be used.

Further, those having a hard code layer or an antireflection film on these substrates are also included in the optical substrate. Therefore,
As the optical substrate, a substrate made of only the above substrate material, a substrate provided with a hard coat layer or an antireflection film on the substrate material, further a hard code layer is provided on the substrate material, and the antireflection film is provided on the hard coat layer. Four types of substrates provided can be illustrated.

The antireflection film (vapor-deposited film) is, for example, ZrO ₂ , SiO ₂ , TiO ₂ , Ta ₂ O ₅ , Y ₂ O ₃ provided for reducing reflection on the surface of an optical substrate such as a lens. , MgF ₂ , Al ₂ O ₃
It refers to a single-layer or multi-layer film formed from the above or a colored film such as CrO ₂ and these are formed by a vacuum deposition method, an ion plating method, a sputtering method or the like.

As the hard code layer, a cured film containing an organic silicon compound, an acrylic compound or the like can be exemplified.

[0024]

INDUSTRIAL APPLICABILITY The present invention provides an optical member having a water-repellent thin film excellent in durability by vacuum-depositing a diluted solution of an organosilicon compound. Furthermore, in the present invention, the refractive index and the film thickness of the water-repellent thin film, which has been difficult to achieve in the past, can be appropriately controlled, and an optical member having a desired water repellency can be provided. Further, it is possible to easily impart water repellency to an optical member having an antireflection film without changing the interference color of the antireflection film, which is difficult to set the color.

[0025]

EXAMPLES The present invention will be specifically described below with reference to examples.

1. Preparation of water repellent agent A compound represented by the unit formula C _p F _{2p + 1} CH ₂ CH ₂ Si (NH) _1.5 was used.
-A solution (trade name: KP-801, Shin-Etsu Chemical Co., Ltd.) diluted to 3% by weight with xylene hexachloride was used as the water repellent agent.

2. Preparation of plastic lens with antireflection film As a plastic lens, a diethylene glycol bisallyl carbonate polymer type plastic lens (HO
YA Co., Ltd. Hi-Lux, refractive index 1.499 degree 0.00, was used to first form an underlayer of silicon dioxide on this plastic lens by vacuum deposition (vacuum degree 2 × 10 ⁻⁵ Torr). The rate was 1.46, and the film thickness was 0.5λ (λ is 550 nm)]. Next, on this underlayer, a layer made of titanium dioxide (film thickness 0.06λ) is formed by an ion beam assist method in which the plastic lens is irradiated with an oxygen ion beam while the plastic lens is heated, and a layer is formed by a vacuum vapor deposition method. Layer made of silicon (film thickness 0.12λ), and further made of titanium dioxide by the ion beam assist method (film thickness)
The first layer, which is a three-layer equivalent film made of 0.06λ) [refractive index 1.
70 and a film thickness of 0.24λ]. Next, on this first layer, a second layer (refractive index 2.4) formed of titanium dioxide by an ion beam assist method in which the plastic lens is irradiated with an oxygen ion beam while the plastic lens is heated.
0, film thickness 0.5 λ) was formed. Then on this second layer,
A third layer (refractive index: 1.46, film thickness: 0.25λ) made of silicon dioxide was formed by a vacuum deposition method (degree of vacuum: 2 × 10 ^-5 Torr) to obtain a plastic lens with an antireflection film.
The luminous reflectance of this lens was 0.4%.

3. Evaluation of physical properties (1) Static contact angle to water Using a contact angle meter (CA-D type, manufactured by Kyowa Interface Science Co., Ltd.), water droplets with a diameter of 1.5 mm were made at the needle tip at room temperature. , Was made to touch the top of the convex surface of the lens to form a droplet. The angle between the droplet and the surface generated at this time was measured and used as the static contact angle.

(2) Luminous reflectance (single-sided) Luminous reflectance was measured using a U3410 type self-recording spectrophotometer manufactured by Hitachi Ltd.

(3) Appearance The presence or absence of color unevenness of interference color and interference color change was visually inspected. (I investigated whether it could be used as an eyeglass lens)

(4) Durability The chamois was immersed in water at 25 ° C. for 5 minutes and then taken out in the air. A load of 500 g was applied to the chamois and the surface of the plastic lens having the water-repellent film was rubbed 500 times, and then the static contact angle to water was measured by the same method as described in (1).

(5) Thickness measurement of thin film The thickness was measured by ellipsometry (polarization reflection analysis method). Mizojiri optics, ellipsometer λ = 633nm (He-Ne laser)

(6) Measurement of film refractive index It was measured by ellipsometry (polarization reflection analysis method). Mizojiri optics, ellipsometer λ = 633nm (He-Ne laser)

Example 1 A sintering filter made of stainless steel (mesh 80 to 100 microns, 18φ) impregnated with 0.20 ml of the water repellent agent was used.
X3 mm) was set in a vacuum vapor deposition apparatus and heated to 250 ° C. The degree of vacuum of the apparatus was 10 ^-4 Torr. A film was formed on the plastic lens under the above conditions.

As a result, a thin film having a film thickness of 30 Å and a film refractive index of 1.35 was formed. The water contact angle was 110 °. The luminous reflectance was 0.4%, which was not different from the luminous reflectance of the antireflection film before the treatment, no color unevenness of interference color, no interference color change was observed, and the durability was good.

Examples 2 to 4 All were the same as Example 1 except that the water repellent treatment agent was changed to 0.16 ml (Example 2), 0.24 ml (Example 3), and 0.18 ml (Example 4). The same was done. As a result, as shown in Table 1, a thin film having excellent physical properties as in Example 1 was formed.

Comparative Example 1 A water repellent treatment agent (same as in Example 1) was applied by dip coating to a plastic lens with an antireflection film similar to that in Example 1 at a pulling rate of 0.5 cm / sec. After coating, heat treatment was performed at 50 ° C. for 1 hour to form a thin film on the lens. The film refractive index is 1.
33 and the film thickness was 100 Å.
As a result, as shown in Table 1, the water contact angle was 110 °, but the antireflection property was deteriorated and the durability was such that the water contact angle was 67 °.
And the interference color unevenness and the interference color change were observed, which further deteriorated the reflection characteristics of the antireflection film.

Comparative Example 2 Comparative Example 1 except that the concentration of the water repellent treatment agent was 0.01% by weight.
It carried out similarly to. As a result, as shown in Table 1, the reflection characteristics of the antireflection film were not deteriorated and no interference color color unevenness or interference color change was observed, but the water contact angle was as low as 83 °, and durability (water contact The angle was as low as 60 °.

Reference Example 1 The water contact angle of an antireflection plastic lens similar to that in Example 1 was measured without treatment with a water repellent agent. As a result, the water contact angle was 7 °.

[0040]

[Table 1]

Claims (3)

(57) [Claims] 1. An organic silicon compound represented by the following unit formula (I): C _p F _{2p + 1} CH ₂ CH ₂ Si (NH) _1.5 (where p is an integer of 1 or more) is diluted with a solvent. A method for producing an optical member having a thin film, which comprises heating and evaporating the solution as a solution under vacuum to deposit the solution on the optical substrate to form a thin film on the optical substrate. 2. The optical element according to claim 1, wherein the porous material is impregnated with a solution prepared by diluting the organosilicon compound with a solvent, and the porous material impregnated with the solution is heated to evaporate the organosilicon compound. A method of manufacturing a member. 3. The method for producing an optical member according to claim 1, wherein the thin film has a refractive index in the range of 1.30 to 1.37 and a film thickness in the range of 1 to 50 Å.