JPH09127303A - Antifogging product having antireflection performance and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain antireflection performance, wear resistance, resistance against water spots, contamination resistance and antifogging property by forming the surface of a product in such a manner that an inorg. material having water repellency and a hydrophilic material are present and controlling the static contact angle of the surface with water to a specified or larger. SOLUTION: An antireflection film is formed by vacuum vapor deposition while introducing a gas. The gas is introduced into the uppermost layer having low refractive index of the antireflection film. Silicon dioxide is preferably used for the low refractive index layer of the antireflection film, since a hard film can be formed even at low temp. In this case, the uppermost layer of a single-layer or multilayered antireflection film has pores and minute recesses and the packing rate of the inorg. material in the uppermost layer is controlled to <=0.95. A hydrophilic material is made present in the pores and minute recesses so that the uppermost surface consists of the inorg. material and the hydrophilic material. The static contact angle of the inorg material surface with water is controlled to >=90 deg.. As for the hydrophilic material, surfactants, hydrophilic monomers and polymers of these monomers can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to lenses for spectacles and cameras having anti-fog performance, window glasses, car windshields, helmet shields, underwater glasses, mirrors used in bathrooms, and the like. .

[0002]

2. Description of the Related Art As a method of imparting antifogging performance to articles,
Conventionally, various methods as described below have been adopted.

A method of imparting an antifogging property by kneading a surfactant into the synthetic resin substrate itself or copolymerizing a hydrophilic monomer to form a synthetic resin substrate is disclosed in JP-A-51- 1078
41, JP-A-55-102632, JP-B-57-317
35, JP-A-58-160325, JP-A-60-141
727, JP-A-61-114201, JP-A-61-11
4202, JP-A-62-2202, JP-A-62-220
3, etc.

A method of applying a coating having an antifogging property to an article is also well known, and is disclosed in JP-B-45-18972, JP-B-50-1710, and JP-A-52-146791.
3-39347, JP-A-55-99930, JP-A-55.
-750, JP-A-55-148283, JP-A-57-1.
19973, JP-B-58-1688, JP-A-59-15
473, Japanese Patent Publication No. 62-28986, Japanese Patent Laid-Open No. 1-2498
18, JP-A-2-18048, JP-A-2-17307
8, etc.

The above-mentioned method aims to achieve antifogging performance by imparting hydrophilicity and water absorption to the substrate itself or the thick coating layer.

As a method for directly imparting antifogging performance to an inorganic substance such as glass having poor water absorption, a method of treating the outermost surface to make it hydrophilic or hydrophobic is known.
-56177, JP-B-57-61294, JP-A-2-2
52638, JP-A-4-366140, and JP-A-5-96.
679, JP-A-5-155641, and JP-A-54-105.
120, JP-A-60-210641, and JP-A-62-57.
484, Japanese Patent Laid-Open No. 223411, etc.

Graft polymerization as a method of surface modification is
It is disclosed in JP-A-1-230644, JP-A-2-38431, and JP-A-4-225301.

[0008] Further, as a patent combining the pores and irregularities of an inorganic substance with a hydrophilic substance and a patent utilizing the irregularities on the surface, there are Japanese Patent Laid-Open No. 49-18910 and Japanese Patent Publication No. 52-1132.
1, JP-A-54-57516, JP-A-61-9104
2, Japanese Patent Publication No. 1-58481, and JP-A-3-194501.

In order to impart antifogging performance to articles, including the above-mentioned methods, 1) the substrate is made to absorb water. 2) Make the substrate surface hydrophilic. 3) Make the substrate surface water repellent.
4) Increase the surface temperature of the article so that moisture in the air does not condense on the surface. The following four points have been proposed from the past,
Various attempts have been made.

[0010]

However, the conventional method has the following problems.

Although a method of imparting antifogging performance to the resin base material itself or the resin coating layer can provide sufficient performance as antifogging performance, a resin having hydrophilicity / water absorption becomes soft when water is absorbed, which is extremely high. It was easily scratched. If it is used in a portion such as a spectacle lens that requires abrasion resistance, the optical characteristics deteriorate due to scratches and it cannot be put to practical use. Furthermore, dirt in the air, such as cigarette smoke, is easily adsorbed, and the optical article is colored.

Further, the biggest drawback of these methods is that the outermost surface cannot be subjected to a surface treatment for improving the optical characteristics such as an antireflection film. An antireflection film which is widely used and has a good performance is an antireflection film made of an inorganic material, and the surface of the inorganic material such as silicon oxide must have antifogging performance.

As a method for imparting antifogging performance to the surface of glass or the surface of an inorganic substance, there is a method of applying a generally used surfactant to the surface, but there is a problem in durability.
Surfactant is easily removed by water.

In addition, there is a method of forming an extremely thin film by using a hydrophilic substance on the glass surface or the surface of an inorganic substance to achieve antifogging performance. According to the prior art, the binding between these substances and the surface is performed. However, the substances were easily removed and the antifogging performance could not be maintained for a long time.

On the contrary, in the case of imparting water repellency, it is difficult to say that the conventional techniques show that the contact angle of water on the surface is only about 140 ° and that sufficient antifogging performance is obtained.

In order to solve the above-mentioned problems, a method has been proposed in which the surface of an inorganic substance is treated with a silane coupling agent and then the reactive surfactant is reacted, but the structure of the reactive surfactant is also proposed. In some cases, a sufficient antifogging effect was not obtained.

A combination of an inorganic substance and a hydrophilic substance has also been proposed as having both antireflection properties and antifogging properties. In particular, Japanese Patent Laid-Open No. 3-194501 describes a fine gap in an inorganic coating film and antifogging using a hydrophilic substance, but there is no detailed description about the fine structure and the uppermost layer of the antireflection film. Further, the surface of these inorganic substances was liable to be stained with water or easily stained.

Therefore, the present invention has solved the above problems and has excellent antifogging performance without deteriorating the optical characteristics such as antireflection characteristics of an article, abrasion resistance, water proof, and stain resistance. The object is to obtain an article having durability.

[0019]

According to the first aspect of the present invention,
The uppermost layer of the single-layer and multi-layered antireflection film made of an inorganic substance provided on the substrate has at least one of pores and fine irregularities, and the filling rate of the inorganic substance of the uppermost layer is 0.
95 or less, a hydrophilic substance is present in the pores and fine irregularities, and the outermost surface is composed of an inorganic substance and a hydrophilic substance,
The static contact angle of water on the surface of the inorganic material is 90 ° or more.

According to a second aspect of the present invention, the uppermost layer of the single layer and the multilayer antireflection film made of an inorganic substance provided on the substrate is formed by vacuum vapor deposition while introducing gas, and then the hydrophilic substance is formed. The uppermost layer is treated with, the hydrophilic substance is fixed to the pores and fine irregularities of the uppermost layer, and the surface of the inorganic substance is treated with a substance having water repellency.

Optical parts such as lenses, glass, and mirrors are often provided with a single-layer or multi-layer antireflection film for the purpose of improving the transmittance and reducing the reflectance. These antireflection films are formed by a vacuum evaporation method or a sputtering method. In the case of vacuum vapor deposition, the formed film has a lower filling rate than the bulk,
The surface is also uneven. Since a high density and hard film is required in general vapor deposition, it is necessary to increase the filling rate. Therefore, the degree of vacuum before and during vapor deposition is often high.

On the other hand, in the present invention, the antireflection film is formed by vacuum vapor deposition while introducing gas. By introducing a gas during vapor deposition and applying a low vacuum, the filling rate of the film can be further lowered. The introduced gas is preferably an inert gas such as Ar to avoid reaction with the film. The film formed in this manner has a large number of pores and fine irregularities, which are larger than those in the case where no gas is introduced. The gas introduction amount is preferably 2 × 10 ⁻⁵ hPa or more in terms of the degree of vacuum before vapor deposition. Incidentally, taking a silicon dioxide film as an example, the refractive index when gas is not introduced is 1.45 and the filling rate is about 0.98, but Ar gas is introduced until the degree of vacuum reaches 4 × 10 ⁻⁴ hPa. Then, when vapor deposition is performed, the refractive index is 1.36 and the filling rate is 0.7.
It will be about 8. In order to obtain sufficient antifogging performance, it is important that the filling rate is 0.95 or less.

The layer for introducing gas is the uppermost layer of the antireflection film. In the case of a single-layer antireflection film, the single layer itself is used. As the uppermost layer, a low refractive index layer is used due to the design of the antireflection film. It is acceptable to introduce gas into the low-refractive index layer to lower the refractive index, but if gas is introduced into the high-refractive index layer and the refractive index of the high-refractive index layer decreases, high-performance reflection is achieved. It is difficult to obtain prevention properties. Further, the surface hardness cannot be obtained either. Therefore, in the present invention, gas is introduced into the uppermost low refractive index layer.

When the base material is a synthetic resin, vapor deposition cannot be performed at a high temperature in order to avoid deformation of the base material. Therefore, for the low refractive index layer of the antireflection film, silicon dioxide is often used because it gives a hard film even at low temperatures.

In the present invention, the hydrophilic substance is fixed to the pores and fine irregularities of the uppermost layer formed by introducing the gas as described above. As the hydrophilic substance, fatty acid soap, anionic surfactant such as alkylbenzene sulfonate, cationic surfactant having a quaternary ammonium group, amphoteric surfactant such as long-chain alkylamino acid, polyoxyethylene nonylphenyl ether, etc. Nonionic surfactants such as, surfactants such as, glucosylethylmethacrylate, methacrylic acid, acrylic acid, 2-hydroxylethylmethacrylate, acrylamide, N, N-dimethylacrylamide, N-vinylpyrrolidone, N- (2-methacrolein (Iloxyethyl) -2-pyrrolidone, glyceryl methacrylate, polyethylene glycol methacrylate, polyethylene glycol acrylate, and other hydroxylalkyl (meth) acrylates, polyalkylene glycol mono (meth) acrylate , May be mentioned (meth) acrylamides, N- vinyllactams, the hydrophilic monomers and polymers consisting of equal.

These hydrophilic substances may be used alone or as a mixture. Furthermore, if it is a hydrophilic substance, it is not limited to these.

Hydrophilic monomers and reactive terminal groups such as vinyl group, acryl group, methacryl group, glycidyl group, allyl group, epoxy group, mercapto group, cyano group, isocyano group, amino group and sulfone group, hydroxyl group, ammonium. When using a reactive surfactant having a hydrophilic portion such as chloride as a hydrophilic substance, after attaching these substances to the pores and surface irregularities, electromagnetic waves such as heat, ultraviolet rays, radiation such as electron beams, etc. The reaction can be promoted by the and can be firmly fixed. Furthermore, when the uppermost layer is silicon dioxide, if a silane coupling agent having a reactive group with both a reactive hydrophilic substance and silicon dioxide is used together, the adhesion to the film is improved and the anti-fogging property is maintained. The durability such as the property is improved.

By removing the hydrophilic substance, which protrudes from the pores and fine irregularities and forms a film on the inorganic substance, and the unreacted monomer that could not contribute to the reaction, by washing off, it is possible to reflect before treatment. It is possible to perform processing that does not change the appearance such as prevention characteristics.

In the present invention, the inorganic substance existing on the surface is further treated with a substance having water repellency. This may be before or after fixing the hydrophilic substance. When the contact angle of the surface after the treatment is 90 ° or more, sufficient water proofing and stain resistance can be obtained. When the inorganic substance is silicon dioxide, a silane coupling agent containing fluorine is effective. Examples of the silane coupling agent include, but are not limited to, halogenated silanes, silane compounds having terminal silanols, alkoxysilanes, aminosilanes, silazanes, silicon-functional silyl isocyanates, and the like. These substances may be used alone or in a mixture.

The treatment is preferably carried out at a low temperature which does not affect the formed vapor deposition film. The treatment method is a method in which the treatment liquid is applied by a dipping method or a spin method and then heated and reacted,
A method of reacting as a gas in a vacuum chamber or in the atmosphere can be used. The reaction method is not particularly limited.

The outermost surface formed as described above is a surface on which an inorganic substance having water repellency and a hydrophilic substance are present.

The article to which the anti-fog property is imparted may be any article, but it is very effective in use as long as it is an optical article such as a lens, a mirror, a window, goggles, and underwater glasses.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail based on Examples, but the present invention is not limited to these Examples.

Example 1 A lens made of diethylene glycol bisallyl carbonate, which had been previously immersed in a sodium hydroxide solution (0.1N), washed well with water, and dried, was coated with the following coating solution by a dipping method to give a film thickness of 2.5 μm.
m to obtain a hard coat layer by heating and curing at 130 ° C. for 2 hours.

(Preparation of coating liquid) In a reaction vessel equipped with a stirrer, 206 g of ethanol, 396 g of ethanol-dispersed colloidal silica (“Oscar 1232” manufactured by Catalysts & Chemicals Co., Ltd., solid content 30%), γ-glycidoxy Partial hydrolyzate of propyltrimethoxysilane 312
g, 0.2 g of a flow control agent (“L-7604” manufactured by Nippon Unicar Co., Ltd.) and 86 g of a 0.05N acetic acid aqueous solution were added, and the mixture was stirred at room temperature for 3 hours to obtain a coating liquid.

The coated lens obtained as described above was set in a vacuum chamber, and the coating surface was subjected to antireflection treatment at a substrate temperature of 50 ° C. by vacuum vapor deposition. The film structure is such that, from the lens side in terms of optical film thickness, the synthetic film thickness of the silicon dioxide layer is λ / 4, the zirconium oxide layer and the silicon dioxide layer is λ / 4, the zirconium oxide layer is λ / 4, and the uppermost silicon dioxide layer. The layer was λ / 4. (Λ is 520 nm)
Here, when forming the uppermost silicon dioxide layer, argon gas was introduced and vapor deposition was performed in a state where the degree of vacuum was 2 × 10 −4 hPa. The uppermost layer had a refractive index of 1.41 and a filling rate of 0.89. The lens with the antireflection film thus formed was treated with the reaction solution for antifogging treatment prepared by the following procedure.

98 g of pure water containing 2 g of acrylamide, 0.1 g of azobisisobutyronitrile and 0.01 g of a surfactant.
In addition to the above, a uniform aqueous solution was prepared to obtain a coating reaction solution.

The lens with the antireflection film formed above was immersed in this coating reaction solution at a liquid temperature of 15 ° C. for 1 minute.
After that, in an atmosphere with a humidity of 60% and a temperature of 25 ° C., 1 cm /
The lens was pulled up at the speed of a minute. After pulling up, UV irradiation and heating to 50 ° C. were performed in a nitrogen stream using a high pressure mercury lamp. Then, it wash | cleaned by trichloroethylene. No significant change was observed in the appearance and antireflection property of the lens after washing.

Next, the lens produced as described above is
(Perfluorooctyl) ethyltriaminosilane 3g
Is immersed in 97 g of a mixed solvent of C ₅ F ₁₂ and C ₇ F ₁₆ containing C ₆ F ₁₄ as a main component (FX3250 manufactured by Sumitomo 3M) for 5 minutes at a liquid temperature of 20 ° C., and after the immersion, a relative humidity of 50 %,
It was taken out in an atmosphere at a temperature of 50 ° C. and left for 10 minutes. Then, the lens was wiped off with acetone.

The method for evaluating the antifogging property of the obtained article is "JIS
-S4030 Grade 1 to 4 were evaluated according to the anti-fog property at low temperature part of "Test method for anti-fog agent for eyeglasses" (1st grade is the best antifogging performance, 4th grade is the worst). To evaluate the durability of the
After applying a load of kg and rubbing 500 times, the degree of deterioration of the antifogging property was evaluated by the above antifogging evaluation method. For the test of water resistance, the surface of the lens was dried by tap water, and the residue was wiped off with a cloth. The residue was evaluated as C when remaining, A as completely wiped, and B as partially remaining.

The evaluation results are shown in Table 1 together with Examples and Comparative Examples.

According to the above-mentioned constitution, the hydrophilic substance and the silicon dioxide having water repellency are present on the surface, and at the same time, the anti-reflection performance, the water proofing resistance, and the durable anti-fogging having the stain resistance are realized. can do.

[0043]

[Table 1]

Example 2 After forming an antireflection film on the coated lens prepared in Example 1, output 40
Introducing 2-hydroxyethyl methacrylate into the vacuum chamber while performing treatment with 0 W argon RF plasma,
It was brought into contact with the antireflection surface in a gas state, and plasma polymerization was carried out to the extent that no film was formed on the surface. Then, bis (perfluoropropylmethyl) diaminosilane was introduced into the vacuum chamber and reacted with silicon dioxide on the surface.

The obtained lens was evaluated by the same evaluation method as in Example 1. The results are shown in Table 1.

According to the above-mentioned constitution, the hydrophilic substance and the silicon dioxide having water repellency are present on the surface, and at the same time, the anti-reflection performance and the water proofing resistance and the stain-proofing and the durable anti-fog are realized. can do.

Example 3 A reaction liquid for antifogging treatment was prepared by the following procedure. That is, 1 g of 2-hydroxyethyl acrylate, 0.5 g of N, N-dimethylacrylamide,
198 g of 50% aqueous ethanol solution, azobis (2,4-
0.001 g of dimethyl valeronitrile) and 0.02 g of a polyethylene glycol-based surfactant were added to form a uniform aqueous solution, which was used as a coating liquid.

The lens with the antireflection film prepared in Example 1 was dipped in this solution and pulled up at 10 cm / min.
Heated at 0 ° C. for 1 hour. Then, the lens was washed with water and wiped with acetone.

Next, the lens produced as described above was suspended in a container filled with hexamethyldisilazane vapor and exposed to the vapor to treat the surface. After the treatment, it was wiped off with acetone.

The obtained lens was evaluated by the same evaluation method as in Example 1. The results are shown in Table 1.

According to the above construction, the hydrophilic substance and the silicon dioxide having water repellency are present on the surface, and at the same time, the anti-reflection performance, the water proofing resistance, and the stain-proofing with the durability are realized. can do.

Comparative Example 1 A lens having an antireflection film formed in Example 1 and not treated with 2- (perfluorooctyl) ethyltriaminosilane was used as Comparative Example 1.

Comparative Example 2 A lens in which the uppermost layer of silicon dioxide in Example 1 was formed without introducing an argon gas and was not treated with bis (perfluoropropylmethyl) diaminosilane was used as Comparative Example 2.

[0054]

According to the invention of claim 1, the surface of the article is a surface on which an inorganic material having water repellency and a hydrophilic material are present, and the antireflection performance, abrasion resistance, water proofing resistance, and stain resistance. , And can also have anti-fogging properties.

According to the second aspect of the present invention, the hydrophilic substance can be fixed to the film having a low filling rate, the density of the hydrophilic substance is increased, and the inorganic substance exposed on the surface is made water repellent. It can be imparted, and can have sufficient antifogging performance and antireflection performance, abrasion resistance, water stain resistance, and stain resistance.

Claims (9)

[Claims] 1. An uppermost layer of a single-layer or multi-layered antireflection film made of an inorganic material, which is provided on a substrate, has at least one of pores and fine irregularities, The filling rate is 0.95 or less, a hydrophilic substance is present in the pores and fine irregularities, the outermost surface is composed of an inorganic substance and a hydrophilic substance, and the static contact angle of water on the surface of the inorganic substance is 9
An antifogging article having an antireflection property, which is characterized in that it is 0 ° or more. 2. An uppermost layer of a single layer and a multilayer antireflection film made of an inorganic substance, which is provided on a substrate, is formed by vacuum vapor deposition while introducing gas, and then the uppermost layer is treated with a hydrophilic substance. A method for producing an antifogging article having an antireflection property, which comprises fixing a hydrophilic substance to the pores and fine irregularities of the uppermost layer and treating the surface of the inorganic substance with a substance having water repellency. 3. The antifogging article having antireflection performance according to claim 1, wherein the base material is a synthetic resin lens. 4. The antifogging article having antireflection properties according to claim 1, wherein the uppermost layer is made of silicon dioxide and a substance containing silicon dioxide as a main component. 5. The method for producing an antifogging article having antireflection performance according to claim 2, wherein the base material is a synthetic resin lens. 6. The method for producing an antifogging article having antireflection performance according to claim 2, wherein the uppermost layer is made of silicon dioxide and a substance containing silicon dioxide as a main component. 7. The method for producing an antifogging article having antireflection performance according to claim 2, wherein the gas is an inert gas. 8. The hydrophilic substance is a reactive substance, and the reaction is promoted by heating and irradiating electromagnetic waves / radiation after treating the uppermost layer with the hydrophilic substance. A method for producing an antifogging article having the antireflection performance as described. 9. The method for producing an antifogging article having antireflection performance according to claim 2, wherein the substance having water repellency is a silane compound containing fluorine.