JP2000338301A - Optical member and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a member having excellent contamination preventing property such that it prevents deposition of dirt such as fingerprints and sebum or that even when dirt deposits, it can be easily wiped off, by using a contamination preventing agent which is an org. silane compd. containing straight-chain or branched perfluoroalkyl groups to form a contamination preventing layer having a specified thickness range on a base body. SOLUTION: A contamination preventing layer 2 having 50 to 500 √film thickness is formed on at least one surface of a base body 1 by using a contamination preventing agent which is an org. silane compd. containing straight-chain or branched perfluoroalkyl groups. The contamination preventing agent contains an org. silane compd. expressed by Rf-(OC3F6)n-O-(CF2)m-(CH2)l-O-(CH2)s-Si(R)3. In the formula, Rf is a 1-16C straight chain or branched perfluoroalkyl group, (n) is an integer 1 to 50, (m) is an integer 0 to 3, 1 is an integer 0 to 3, (s) is an integer 0 to 6 satisfying 6>=M+1>0, and R is a hydrolyzable group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical member coated with an antifouling layer and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, optical lenses, spectacle lenses, and lenses such as cameras and binoculars are usually provided with an antireflection treatment on the surface thereof in order to reduce the reflection of light and increase the transmittance of light. . When these optical members are used by humans, stains such as fingerprints, sebum, sweat, and cosmetics often adhere.

In general, since the surface energy of the antireflection film is as large as about 60 J / m ² , it is not easy to adhere such dirt and to remove it due to the presence of fine irregularities. In addition, there is a problem that high reflection occurs only in a portion where such dirt adheres, and the dirt is conspicuous.

[0004] Therefore, as means for solving these problems of dirt, there has been devised a method of providing an antifouling layer having a property that dirt hardly adheres and that can easily be wiped off even if it adheres.

[0005] For example, Japanese Patent Application Laid-Open No. 64-86101 discloses an anti-reflection film formed by providing an antireflection film mainly composed of silicon dioxide on the surface of a substrate and further treating the surface with a compound containing an organic silicon substituent. There have been proposed scratch-resistant antireflective coating articles.

Japanese Unexamined Patent Publication No. 4-338901 proposes a stain-resistant and scratch-resistant CRT filter in which a silanol-terminated organic polysiloxane is similarly coated on the surface of a substrate.

Further, Japanese Patent Publication No. 6-29332 discloses that
A low-reflection and antifouling plastic having an antireflection film on a plastic surface comprising a mono- or di-silane compound containing a polyfluoroalkyl group and a halogen, alkyl or alkoxy silane compound has been proposed.

Further, Japanese Patent Application Laid-Open No. 7-16940 discloses that
Optical articles have been proposed in which a copolymer of a perfluoroalkyl (meth) acrylate and a monomer having an alkoxysilane group is formed on an optical thin film mainly composed of silicon dioxide.

[0009]

However, the above-described conventional antifouling layer forming technique has insufficient antifouling properties, and in particular, it is difficult to wipe off dirt such as fingerprints, sebum, sweat, and cosmetics. However, there is a problem that the antifouling performance is greatly reduced with use. Therefore, an optical member excellent in antifouling property and durability is desired.

[0010] The present invention is to solve the above problems of the prior art, and a first object of the present invention is to
The present invention is to provide various optical members having excellent antifouling properties such that fingerprints, sebum, perspiration, and stains such as cosmetics are prevented from adhering and can be easily wiped off even if adhered. A second object is to provide a method for easily forming an antifouling layer having excellent antifouling properties and durability on a surface of a substrate to be treated without using a diluting solvent by accurately controlling the film thickness. It is.

[0011]

The invention of claim 1 of the present invention uses an antifouling agent which is an organic silane compound containing a linear or branched perfluoroalkyl group on at least one surface of a substrate, An optical member characterized by forming an antifouling layer having a thickness of 50 to 500 °.

According to a second aspect of the present invention, in the optical member according to the first aspect, the antifouling agent contains an organic silane compound represented by the following chemical formula (hereinafter referred to as formula 1). is there. _{R f - (OC 3 F 6} ) n -O- (CF 2) m - (CH
_{2) l -O- (CH 2)} s -Si (R) 3 ( where, R _f
Is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms, n is an integer of 1 to 50, m is an integer of 0 to 3, l
Is an integer of 0-3, s is an integer of 0-6, provided that 6 ≧ m + 1
> 0, R represents a hydrolysis group. )

[0013] In a third aspect of the present invention, the base material is:
Optical lenses, spectacle lenses, lenses for cameras and binoculars or other optical devices, beam splitters, prisms,
3. The optical member according to claim 1, wherein the optical member is a mirror, a window glass, an antireflection film, or an optical filter.

According to a fourth aspect of the present invention, there is provided a resistance heating method,
The antifouling agent according to claim 1 or 2 is heated and evaporated by using at least one method selected from an electron beam heating method, a light heating method, an ion beam heating method, and a high-frequency heating method. A method for producing an optical member, comprising forming an antifouling layer on a surface.

[0015] The invention of claim 5 of the present invention is to improve the fixing property of the antifouling layer by heating, humidifying, irradiating ultraviolet light, irradiating infrared light or irradiating electron beam after forming the antifouling layer. A method for manufacturing an optical member according to claim 4, wherein:

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The present invention relates to an optical system in which an antifouling layer having a thickness of 50 to 500 ° is formed on at least one surface of a substrate using an antifouling agent which is an organic silane compound containing a linear or branched perfluoroalkyl group. It is a member.

Further, according to the film forming method of the present invention, a substrate to be treated such as an optical member having a desired antifouling layer in which the film thickness of the antifouling layer has been accurately controlled in the order of Angstrom, which has been difficult in the past, is referred to as (Referred to as an optical member).

By freely controlling the thickness of the antifouling layer, it is possible to impart necessary or suitable antifouling performance to each optical member.

As a result, the optical member having the antireflection film can easily be imparted with antifouling property without changing the interference color of the antireflection layer whose color is difficult to set.

Heretofore, it has been difficult to reliably fix an antifouling layer having a thickness of 50 to 500 ° to various optical members. If the thickness is too small, sufficient antifouling performance cannot be obtained.
Conversely, if the thickness is too large, there are problems such as the appearance of the surface being cloudy in appearance depending on the type of the optical member, and the antifouling performance is significantly reduced if the surface is rubbed.

However, in the present invention, various optical members are used.
After forming the antifouling layer, the hydrolysis reaction between the antifouling agent and the surface of the substrate to be treated is promoted by heating, humidifying, irradiating ultraviolet rays, irradiating infrared rays, or irradiating an electron beam, and the film thickness is easily 50 to 500.
It is possible to fix the antifouling layer of Å. Than this,
An optical member having excellent antifouling properties and durability can be provided without impairing the optical performance of various optical members.

Further, the present invention also provides an optical member using an antifouling agent, comprising an organic silane compound represented by the formula 1.

In the formula 1, R _f is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms, particularly preferably CF ₃ —, C ₂ F ₅ — and C ₃ F ₇ —.

R is a hydrolyzable group, —Cl, —Br,
^{-I, -OR 1, -OOCR 1,} -OC (R 1) C = C
(R ² ) ₂ , -ON = C (R ¹ ) ₂ , -ON = CR ³ ,
—N (R ² ) ₂ and —R ² NOCR ¹ are preferred. Here, R ¹ is an aliphatic hydrocarbon group having 1 to 10 carbon atoms such as an alkyl group, or an aromatic hydrocarbon group having 6 to 20 carbon atoms such as a phenyl group, and R ² is a carbon atom such as a hydrogen atom or an alkyl group. An aliphatic hydrocarbon group having 1 to 5 and R ³ are a divalent aliphatic hydrocarbon group having 3 to 6 carbon atoms such as an alkylidene group.

In the formula 1, not only one kind of the hydrolyzable group R but also a mixture of two or more kinds can be used. In particular, -OCH ₃ , -OC ₂ H ₅ , -OOCC
H ₃ and —NH ₂ are preferred. N is an integer of 1 to 50; m is an integer of 0 to 3; l is an integer of 0 to 3;
Where 6 ≧ m + 1> 0.

In the present invention, in order to form an antifouling layer on a substrate, the antifouling agent is first impregnated into a porous molded product, which is heated and evaporated in a vacuum to form a substrate to be treated. A film is formed thereon. The heating method for heating the porous molded product impregnated with the antifouling agent to evaporate the antifouling agent includes resistance heating, electron beam heating, light heating, ion beam heating, and high frequency heating. Is valid.

The substrate used in the present invention includes:
A transparent one can be typically used. Therefore, it is often ideal to transmit light of all wavelengths,
In reality, there is no 100% transmission. In some cases, a colored base material that transmits only a specific frequency or a translucent base material that actively uses scattering properties may be preferable. In the case of a mirror application, a substrate having no transparency may be preferable.

The substrate may be, for example, an optical lens, a spectacle lens, a lens of a camera or binoculars, or other optical devices, a beam splitter, a prism, a mirror, a window glass, an antireflection film, an optical filter, or the like. Optical member.

[0029]

Embodiments of the present invention will be described below in detail, but the present invention is not limited to the embodiments.

<Example 1> [(1) Preparation of antifouling agent] Sodium hydride / oil suspension was placed in a 100 ml two-necked eggplant type flask equipped with a dropping funnel and a reflux condenser, and the atmosphere was replaced with nitrogen.
After the replacement, washing with n-hexane under nitrogen is performed 4 times.
Repeated times, n-hexane was distilled off under reduced pressure to obtain sodium hydride (0.011 mol).

A hydroxyl group-containing fluororesin (0.01 mol) represented by the following formula 2 is dissolved in 50 g of bis (trifluoromethyl) benzene, and this solution is cooled under ice-cooling to 1 g.
Gently dropped at a rate of drops / sec.

After completion of the dropwise addition, the temperature is changed from the ice bath to room temperature, and the
Stirred for hours. To the sodium alkoxide, chloromethyltrimethoxysilane represented by the following formula 3 (0.1 mol
l) and stirred at room temperature for 2 hours.
Heating and refluxing were performed for 72 hours while controlling to keep 0 ° C.

After completion of the reflux, unreacted sodium hydride and sodium chloride were filtered under reduced pressure, the filtrate was sufficiently washed with water, and bis (trifluoromethyl) benzene and excess chloromethyltrimethoxysilane were distilled off under reduced pressure. An organosilane compound represented by the following formula 4 was obtained.

(Equation 2) C ₃ F ₇ — (OC ₃ F ₆ ) ₂₄ —O
— (CF ₂ ) ₂ —CH ₂ —OH

(Formula 3) ClCH ₂ Si (OCH ₃ ) ₃

(Equation 4) C ₃ F ₇ — (OC ₃ F ₆ ) ₂₄ —O
— (CF ₂ ) ₂ —CH ₂ —O—CH ₂ Si (OCH ₃ ) ₃

5 g of the organosilane compound of the formula 4 was diluted to 10 wt% with perfluorohexane to prepare an antifouling agent.
The porous molded article (pellet) is immersed in this, and impregnated so as to be completely saturated. Take it out of this solution,
After evaporating the solvent, each pellet contains about 2 wt% antifoulant.

[(2) Preparation of Antifouling Layer] The pellets were placed on a molybdenum boat and formed on an antireflection film by a vacuum evaporation method (resistance heating method) to prepare an antifouling layer. After evacuating the inside of the vacuum deposition machine to 5 × 10 ⁻⁵ Torr or less,
The boat was heated to 400 ° C. to evaporate the antifoulant.

[(3) Post-treatment] The antireflection film having the antifouling layer formed thereon was left in a room at a temperature of 40 ° C and a humidity of 90% for 10 hours.

With respect to the antireflection film having an antifouling layer formed in Example 1 described above, the contact angle, the adhesion and wiping properties of an oil-based pen, the adhesion and wiping properties of a fingerprint, the film thickness, the appearance, and the like were as follows. Table 1 shows the results of the evaluation according to the evaluation method. In Table 1, the values in parentheses indicate the characteristics after the wear resistance test.

Comparative Example 1 CF ₃ (CF ₂ ) ₇ (CH
_{2) 2 Si (NH) 3/2} : using [KP801M Shin-Etsu Chemical Co., Ltd.], by wet coating method,
A film was formed on the antireflection film to form an antifouling layer.

Evaluation method: (a) Contact angle measurement: Using a contact angle meter [CA-X: manufactured by Kyowa Interface Science Co., Ltd.], in a dry state (20 ° C.-65% R)
In H), a droplet having a diameter of 1.0 mm was formed at the tip of the needle, and this was brought into contact with the surface of the substrate (solid) to form a droplet. The contact angle is an angle formed by a tangent to the liquid surface at a point where the solid and the liquid come into contact with each other, and is defined as an angle including the liquid. Distilled water was used as the liquid.

(B) Adhesion of oily pen: Using an oily pen (magic ink: No. 500 for fine writing) on the surface of a base material, draw a straight line of 1 cm in length to determine how easily it sticks or stands out. Visual determination was made. The criteria are shown below. ：: The oily pen is repelled into a sphere. ×: The oily pen does not repel and can be written.

(C) Wiping property of oily pen: Cellulose nonwoven fabric [Bencott M]
-3: manufactured by Asahi Kasei Corporation], and the ease of removal was visually determined. The criteria are shown below. ：: The oil pen can be completely wiped off. Δ: Wipe marks of oily pen remain. ×: The oily pen cannot be wiped off.

(D) Adhesiveness of fingerprint: A finger was pressed against the surface of the base material for several seconds to attach a fingerprint, and the stickiness or conspicuousness was visually determined. The criteria are shown below. ：: Fingerprint adhesion is small, and the attached fingerprint is inconspicuous. X: Adhesion of a fingerprint can be recognized.

(E) Wiping of fingerprints: Fingerprints adhering to the surface of the substrate were wiped off with a cellulose nonwoven fabric (Bencott M-3: manufactured by Asahi Kasei Corporation), and the ease of removal was visually determined. The criteria are shown below. ：: The fingerprint can be completely wiped off. Δ: Fingerprint wiping remains. ×: The trace of wiping of the fingerprint spread and could not be wiped off.

(F) Abrasion resistance: The substrate surface is made of a cellulose nonwoven fabric (Bencott M-3: manufactured by Asahi Kasei Corporation) with a load of 5
After rubbing 100 times with 00 gf, the above various physical properties were evaluated.

(G) Film thickness: The cross section of the substrate was measured using a transmission electron microscope.

(H) Appearance: The substrate surface was visually observed from various angles by reflecting or transmitting light. In addition, the transmittance, the reflectance, and the color of the antireflection film were measured using a spectroscope as needed.

[0050]

[Table 1]

FIG. 2 shows that the antireflection film of Example 1 has a contact angle of 110 ° or more when formed with an antifouling layer having a thickness of 50 ° or more, and exhibits high water repellency. In addition, from Table 1, this antireflection film having a contact angle of 110 ° or more can prevent fingerprints and oily pens from adhering, and also has excellent antifouling properties and durability that can be easily wiped off even if they adhere. I understand.

Also in Comparative Example 1, when an antifouling layer having a film thickness of 100 ° or more is formed, relatively high water repellency is exhibited. However, the antifouling properties of fingerprints and oil-based pens are low. On the other hand, the antireflection film of Example 1 has a thickness of the antifouling layer of up to 500.degree.

[0053]

The optical member of the present invention has excellent antifouling performance because the thickness of the antifouling layer is accurately controlled according to the surface of each substrate to be treated. Even if the thickness of the antifouling layer is increased to 500 °, the optical performance and appearance are not impaired.

For this reason, dirt such as fingerprints, sebum, sweat, and cosmetics is hard to adhere, and even if it adheres, it can be easily wiped off, and the antifouling layer has high durability.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an optical member of the present invention.

FIG. 2 is a diagram showing a relationship between a film thickness and a contact angle in Example 1 of the present invention.

[Explanation of symbols]

 1 base material 2 antifouling layer

Claims (5)

[Claims] An antifouling layer having a thickness of 50 to 500 ° is formed on at least one surface of a substrate using an antifouling agent which is an organic silane compound containing a linear or branched perfluoroalkyl group. An optical member, comprising: 2. The optical member according to claim 1, wherein the antifouling agent contains an organic silane compound represented by the following chemical formula. _{R f - (OC 3 F 6} ) n -O- (CF 2) m - (CH
_{2) l -O- (CH 2)} s -Si (R) 3 ( where, R _f
Is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms, n is an integer of 1 to 50, m is an integer of 0 to 3, l
Is an integer of 0-3, s is an integer of 0-6, provided that 6 ≧ m + 1
> 0, R represents a hydrolysis group. ) 3. The method according to claim 1, wherein the base material is an optical lens, a spectacle lens, a lens of a camera or binocular, or a lens of another optical device.
The optical member according to claim 1, wherein the optical member is a splitter, a prism, a mirror, a window glass, an antireflection film, or an optical filter. 4. The antifouling agent according to claim 1 or 2, using at least one method selected from a resistance heating method, an electron beam heating method, a light heating method, an ion beam heating method and a high frequency heating method. A method for producing an optical member, comprising heating and evaporating to form an antifouling layer on the surface of a substrate to be treated. 5. The method according to claim 4, wherein after forming the antifouling layer, heating, humidification, ultraviolet light irradiation, infrared light irradiation, or electron beam irradiation are performed to improve the fixing property of the antifouling layer. A method for manufacturing an optical member.