阅读说明：本技术 具有防水防反射膜的镜片及其制造方法 (Lens with waterproof anti-reflection film and manufacturing method thereof ) 是由 川岸秀一朗 山下照夫 白石幸一郎 于 2018-03-20 设计创作，主要内容包括：本发明提供具有增加的防水膜附着性和耐久性的防水防反射膜的镜片及其制造方法。一种具有防水防反射膜的镜片,其特征在于,在玻璃镜片的表面上至少具有按照基膜和防水膜的顺序层压的防水防反射膜；所述基膜由选自SiO<Sub>2</Sub>、ZrO<Sub>2</Sub>、Al<Sub>2</Sub>O<Sub>3</Sub>、TiO<Sub>2</Sub>、Ti<Sub>3</Sub>O<Sub>5</Sub>、Ta<Sub>2</Sub>O<Sub>5</Sub>和Nb<Sub>2</Sub>O<Sub>5</Sub>的单层或含有2种以上的混合层形成,致密度为70％以上100％以下,膜厚为1nm以上200nm以下；所述防水膜在所述基膜的表面上由含有全氟聚醚基团的有机化合物形成,膜厚为5nm以上50nm以下。(The invention provides a lens having a waterproof antireflection film with increased waterproof film adhesion and durability, and a method for producing the same.A lens having a waterproof antireflection film, characterized by having at least a waterproof antireflection film laminated in the order of a base film and a waterproof film on the surface of a glass lens; the base film is made of SiO 2 、ZrO 2 、Al 2 O 3 、TiO 2 、Ti 3 O 5 、Ta 2 O 5 And Nb 2 O 5 The density of the single layer or the mixed layer containing more than 2 layers is more than 70% and less than 100%, and the film thickness is more than 1nm and less than 200 nm; the water-repellent film is formed of an organic compound containing a perfluoropolyether group on the surface of the base film, and has a film thickness of 5nm to 50 nm.)

1. A lens having a waterproof antireflection film, characterized in that,

a water-repellent antireflection film laminated in the order of a base film and a water-repellent film on the surface of a glass lens;

the base film is made of SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅The density of the single layer or the mixed layer containing more than 2 layers is more than 70% and less than 100%, and the film thickness is more than 1nm and less than 200 nm;

the water-repellent film is formed of an organic compound containing a perfluoropolyether group on the surface of the base film, and has a film thickness of 5nm to 50 nm.

2. The lens with a waterproof antireflection film according to claim 1,

the waterproof antireflection film is laminated on the surface of the glass lens in the order of the antireflection film, the base film and the waterproof film,

the anti-reflection film is formed to have 1 or more layers selected from SiO₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more materials.

3. The lens having a water-repellent antireflection film according to claim 1 or 2, wherein said base film is made of SiO₂And (4) forming.

4. The lens with a waterproof antireflection film according to claim 1, wherein a surface of the glass lens is aspherical.

5. A method for manufacturing a lens having a waterproof antireflection film, comprising the steps of:

on the surface of glass lens with a material selected from SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅A step of forming a base film from the single layer or the mixed layer containing 2 or more materials; and

forming a water-repellent film on the surface of the base film by using an organic compound containing a perfluoropolyether group;

forming the base film and the water-repellent film in the same film forming chamber in which the substrate heating temperature is 250 ℃ or lower while maintaining a reduced pressure.

6. The method for manufacturing a lens having a waterproof antireflection film according to claim 5, comprising the steps of:

forming at least 1 layer of SiO selected from the group consisting of the film forming step and the step of forming a base film on the surface of the glass lens in a 1 st film forming chamber in which the substrate is heated at a temperature of 200 to 350 ℃ inclusive₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅A 1 st step of forming an antireflection film by using the single layer of (1) or a mixed layer containing 2 or more materials;

and a 2 nd step of forming the base film and the water-repellent film in a 2 nd film forming chamber having a substrate heating temperature of 250 ℃ or lower, which is different from the 1 st film forming chamber used in the 1 st step, while maintaining a reduced pressure after the 1 st step.

7. The method of manufacturing a lens having a water repellent antireflection film as claimed in claim 6, wherein the base film is formed by an ion beam assist method or a sputtering method.

8. The method of manufacturing a lens having a water-repellent antireflection film according to any one of claims 5 to 7, wherein the base film is formed to have a film thickness of 1nm to 200nm, and the water-repellent film is formed to have a film thickness of 5nm to 50 nm.

9. The method for producing a lens having a water-repellent antireflection film according to claim 5, wherein SiO is used₂Forming the base film.

Technical Field

The present invention relates to a lens having a waterproof antireflection film and a method for producing the same.

Background

Techniques are known for applying a water-repellent coating on the surface of a lens to increase its water repellency. For example, the following patent documents disclose inventions for forming a water-repellent film of an organic compound on the surface of a lens.

Disclosure of Invention

Problems to be solved by the invention

However, in the structure in which the water-repellent film of an organic compound is formed on the surface of the antireflection film of an inorganic compound formed on the lens surface, there is a problem that the water-repellent film is easily peeled off and the durability of the water-repellent film is poor. In each of the patent documents listed above, a preferable film structure for improving the adhesion and durability of a waterproof film formed on the surface of an inorganic compound is not disclosed.

The present invention has been made in view of the above problems, and an object thereof is to provide a lens having a waterproof antireflection film with improved adhesion and durability of the waterproof film, and a method for manufacturing the same.

Means for solving the problems

The lens having a waterproof antireflection film of the present invention is characterized by having at least a waterproof antireflection film laminated in the order of a base film and a waterproof film on the surface of a glass lens; the base film is made of SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅The density of the single layer or the mixed layer containing more than 2 layers is more than 70% and less than 100%, and the film thickness is more than 1nm and less than 200 nm; the water-repellent film is formed of an organic compound containing a perfluoropolyether group on the surface of the base film, and has a film thickness of 5nm to 50 nm.

In the present invention, it is preferable that the water-repellent antireflection film is laminated in the order of the antireflection film, the base film and the water-repellent film on the surface of the glass lens, the antireflection film being formed to have 1 or more layers selected from SiO₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more materials.

Further, in the present invention, the base film is preferably made of SiO₂And (4) forming.

In the present invention, the surface of the glass lens is preferably aspherical.

The method for producing a lens having a waterproof antireflection film of the present invention is characterized by comprising the steps of: on the surface of glass lens with a material selected from SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅A step of forming a base film by a single layer or a mixed layer containing 2 or more materials, and a step of forming a water-repellent film on the surface of the base film by an organic compound containing a perfluoropolyether group; forming the base film and the water-repellent film in the same film forming chamber in which the substrate heating temperature is 250 ℃ or lower while maintaining a reduced pressure.

In the present invention, it is preferable to have the following steps: forming at least 1 layer of SiO selected from the group consisting of the film forming step and the step of forming a base film on the surface of the glass lens in a 1 st film forming chamber in which the substrate is heated at a temperature of 200 to 350 ℃ inclusive₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅A 1 st step of forming an antireflection film by using the single layer of (1) or a mixed layer containing 2 or more materials; and a 2 nd step of forming the base film and the water-repellent film in a 2 nd film forming chamber having a substrate heating temperature of 250 ℃ or lower, which is different from the 1 st film forming chamber used in the 1 st step, while maintaining a reduced pressure after the 1 st step.

Further, in the present invention, the base film is preferably formed by an ion beam assist method or a sputtering method.

In the present invention, it is preferable that the base film is formed to have a film thickness of 1nm to 200nm, and the water-repellent film is formed to have a film thickness of 5nm to 50 nm.

Further, in the present invention, SiO is preferably used₂Forming the base film.

Effects of the invention

According to the present invention, a lens having a waterproof antireflection film excellent in adhesion and durability of a waterproof film and a method for producing the same can be provided.

Drawings

FIG. 1 is a schematic view of a lens having a water-repellent antireflection film according to this embodiment.

FIG. 2 is an enlarged view of a part of the lens having a water-repellent antireflection film according to embodiment 1.

FIG. 3 is an enlarged view of a part of the lens having a water-repellent antireflection film according to embodiment 2.

FIG. 4 shows example 9 (with a base film (SiO)₂) Graph of the relationship between the number of reciprocations and the contact angle of comparative example 1 (without a base film).

FIG. 5 shows example 9 (base film SiO)₂) And comparative example 2 (base film MgF)₂) Is plotted against the contact angle.

FIG. 6 shows example 6 (base film (SiO)₂): density 100%) and comparative example 3 (base film (SiO) based on₂): compactness 65%) on the contact angle.

Detailed Description

Hereinafter, embodiments of the present invention (hereinafter, simply referred to as "the present embodiments") will be described in detail.

The present inventors have earnestly studied a base film of a waterproofing membrane against an organic compound until the adhesion and durability of the waterproofing membrane are improved. That is, the lens having a waterproof antireflection film of the present embodiment has the following characteristic portions (1) to (3).

(1) The glass lens has at least a water-repellent antireflection film laminated in the order of a base film and a water-repellent film on the surface thereof.

(2) The base film is made of SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more kinds of the above. The density of the basement membrane is more than 70% and less than 100%. The film thickness of the base film is 1nm to 200 nm.

(3) The waterproofing membrane is formed from an organic compound containing a perfluoropolyether group. The thickness of the water-repellent film is 5nm to 50 nm.

FIG. 1 is a schematic view of a lens having a water-repellent antireflection film according to this embodiment. The lens 1 having a waterproof antireflection film shown in fig. 1 is configured to include a glass lens 2 as a substrate and a waterproof antireflection film 3 formed on a light incident side surface of the glass lens 2.

The glass lens 2 is not particularly limited, and is, for example, a glass lens for a monitoring camera and a vehicle-mounted camera. The surface of the glass lens 2 on which the water-repellent antireflection film 3 is formed is, for example, aspherical. The glass lens 2 in fig. 1 may be a meniscus lens having a negative charge, a meniscus lens having a positive charge, a biconvex lens, a biconcave lens, or the like, for example.

The water-repellent antireflection film 3 includes at least a base film and a water-repellent film as described in the above (1). Further, the base film has the characteristic portion of the above (2), and the waterproof film has the characteristic portion of the above (3). Further, optically, the entire waterproof antireflection film 3 exhibits an antireflection effect.

The water-repellent antireflection film 3 will be described in more detail below.

< embodiment 1 >

As shown in fig. 2, the waterproof antireflection film 3 of embodiment 1 is laminated in the order of the antireflection film 4, the base film 5 and the waterproof film 6 from the surface of the glass lens 2.

The antireflection film 4 has 1 or more layers of SiO selected from the group consisting of₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more materials. These inorganic compounds constituting the antireflection film 4 are all transparent oxides.

The antireflection film 4 is adjusted to have a reflectance lower than that of the glass lens 2 alone. Specifically, the refractive index and film thickness of each layer are determined so that the entire lens having the antireflection film 4, the base film 5, and the water-repellent film 6 has a desired spectral reflectance. Therefore, the antireflection film 4 may be 1 layer as long as it has a refractive index lower than that of the glass lens 2. In the case of a multilayer film, the low refractive index layer and the high refractive index layer may be alternately laminated. In this case, the high refractive index layer may have a higher refractive index than the glass lens 2. The antireflection film 4 may be configured by laminating, for example, about 1 to 15 layers, preferably 1 to 10 layers. The number of layers, material, and film thickness of the antireflection film 4 can be variously selected based on the wavelength region in which the reflectance is suppressed.

The thickness of the antireflection film 4 is not limited, but the thickness (total thickness) of the antireflection film 4 is about 50nm to 500 nm.

The base film 5 formed on the surface of the antireflection film 4 shown in fig. 2 is located at the outermost layer of the antireflection film 4. In embodiment 1 shown in fig. 2, the whole including the base film 5, the antireflection film 4, and the waterproofing film 6 is adjusted to satisfy the desired reflectance characteristics.

Further, the base film 5 formed on the surface of the antireflection film 4 may be used as a base of the waterproof film 6. The base film 5 is made of SiO₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more kinds of the above. MgF that can be used as the antireflection film 4 cannot be used in the base film 5, as compared with the inorganic compound constituting the antireflection film 4₂. As shown in the experiment described later, it is understood that MgF is used₂The base film 5 has poor adhesion between the base film 5 and the waterproof film 6, and thus cannot have excellent durability. In the present embodiment, the base film 5 is preferably made of SiO among the above-mentioned materials₂And (4) forming.

The base film 5 has a density of 70% to 100%. The "compactness" of 100% means a state in which the base film 5 has no void portion. If there are void portions, the density is correspondingly reduced. The density of the base film 5 is preferably 80% or more and 100% or less.

From the viewpoint of water repellency and antireflection effect of the water-repellent film 6, the thickness of the base film 5 is preferably 1nm or more and 200nm or less, and is formed thinner than the antireflection film 4. The film thickness of base film 5 is preferably 1nm to 100nm, more preferably 1nm to 50nm, and still more preferably 1nm to 20 nm.

The water-repellent film 6 formed on the surface of the base film 5 is an organic compound containing a perfluoropolyether group. The organic compound containing a perfluoropolyether group has excellent water repellency and oil repellency. The organic compound containing a perfluoropolyether group is not particularly limited, and for example, a perfluoropolyether-modified silane can be mentioned.

From the viewpoint of the water-repellent property of the water-repellent film 6, the film thickness of the water-repellent film 6 is 5nm to 50 nm. Thus, the waterproof film 6 is a thin film and coated on the surface of the base film 5. The thickness of the water-repellent film 6 is preferably 5nm to 20 nm.

< embodiment 2 >

As shown in fig. 3, the waterproof antireflection film 3 of embodiment 2 is laminated on the surface of the glass lens 2 in the order of the base film 5 and the waterproof film 6. Embodiment 2 is configured by removing the antireflection film 4 shown in embodiment 1.

For the film constitution of the base film 5 and the waterproofing film 6, refer to the description of embodiment 1 above.

In embodiment 2 shown in fig. 3, base film 5 is preferably formed of a material having a lower refractive index than glass lens 2. The base film 5 is preferably made of SiO₂And (4) forming.

Further, in fig. 2, between the surface of the glass lens 2 and the antireflection film 4, or in fig. 3, between the surface of the glass lens 2 and the base film 5, any pretreatment coating (not shown) may be applied.

As described above, in embodiment 1 and embodiment 2, the material, film thickness, and compactness of base film 5 are specified, and the material and film thickness of waterproof film 6 are specified. As described above, the base film 5 has high density and a wide bonding surface with the waterproof film 6. That is, the base film 5 in the present embodiment has a large number of binding molecules per unit area and high binding property. Accordingly, a proper dehydration condensation reaction occurs between the hydroxyl groups of the base film 5 and the waterproofing membrane 6, and a strong covalent bond is formed between the base film 5 and the waterproofing membrane 6. Further, the waterproof film 6 is formed of a thin film, and the degree of bonding of the entire waterproof film 6 can be increased.

As described above, in the present embodiment, the adhesion of the waterproof film 6 can be improved, and as shown in a friction test described later, the peeling of the waterproof film 6 can be suppressed, and high durability can be obtained.

As shown in embodiment 1, the water-repellent film 6 of an organic compound is not directly formed on the surface of the antireflection film 4 of an inorganic compound, but the water-repellent film 6 is formed through the base film 5 having a predetermined material, density, and film thickness. This can improve the adhesion and durability of the waterproof film 6, and can obtain an excellent antireflection effect.

< method for producing lens with waterproof antireflection film >

First, a method for producing a lens having a water-repellent antireflection film according to embodiment 1 shown in FIG. 2 will be described. In embodiment 1 as shown in fig. 2, the manufacturing process may be divided into a 1 st process and a 2 nd process.

(step 1)

In the step 1, an antireflection film 4 is formed on the surface of the glass lens 2. At this time, the substrate heating temperature in the film forming chamber (hereinafter referred to as the 1 st film forming chamber) was set to 200 ℃ to 350 ℃ and kept at a reduced pressure. The substrate heating temperature refers to a heating temperature for the glass mirror plate 2. In the present embodiment, since the substrate is the glass lens 2, the heating temperature can be as high as 200 ℃ or more. In addition, in the present embodiment, the substrate heating temperature is preferably set to 250 ℃ or higher and 350 ℃ or lower.

In the 1 st step, 1 or more layers selected from SiO are formed in the 1 st film forming chamber in which the substrate heating temperature is set as described above while the pressure is maintained in the 1 st film forming chamber₂、MgF₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅The antireflection film 4 is formed of a single layer or a mixed layer containing 2 or more kinds of materials.

After the formation of the antireflection film 4, the lens having the antireflection film is taken out from the 1 st film forming chamber.

(step 2)

Then, a lens having an antireflection film is set in a film forming chamber (hereinafter referred to as a 2 nd film forming chamber) different from the 1 st step. In the 2 nd step, the substrate heating temperature in the 2 nd film forming chamber is set to 250 ℃ or lower, and the pressure is reduced. In this case, the substrate heating temperature in the 2 nd step is preferably set to a temperature lower than the substrate heating temperature in the 1 st step. In this embodiment, the substrate heating temperature is preferably set to 100 ℃ or lower. The substrate heating temperature may be set to normal temperature (25 ℃). A more preferable range of the substrate heating temperature is a range from room temperature to 100 ℃.

In the step 2, SiO is used on the surface of the antireflection film 4₂、ZrO₂、Al₂O₃、TiO₂、Ti₃O₅、Ta₂O₅And Nb₂O₅Or a mixed layer containing 2 or more materials forms the base film 5. In this case, base film 5 is preferably formed to have a film thickness of 1nm to 200 nm. The film thickness of base film 5 is more preferably 1nm to 100nm, still more preferably 1nm to 50nm, and still more preferably 1nm to 20 nm.

Further, it is preferable to form the base film 5 by Ion-beam Assisted Deposition (IAD) or sputtering. In the ion beam assist method, during vacuum vapor deposition, gas ions are irradiated to the surface of a glass lens as a substrate with an ion gun. The ion beam assisted method can increase the adhesion to the surface of the antireflection film 4 and can easily and appropriately adjust the density of the base film 5 to 70% or more and 100% or less (preferably 80% or more and 100% or less). The ion beam assist method is also applicable to vapor deposition of the antireflection film 4.

Next, in the 2 nd step, the water-repellent film 6 composed of an organic compound having a perfluoropolyether group is formed in the same 2 nd film forming chamber (substrate heating temperature is 250 ℃ or lower, preferably 100 ℃ or lower) as the film formation of the base film 5 while maintaining the reduced pressure. At this time, the water-repellent film 6 may be vapor-deposited by an Electron Beam method (Electron Beam: EB) or a resistance heating vapor deposition method.

The water-repellent film 6 is preferably formed to have a film thickness of 5nm to 50nm, more preferably 5nm to 20 nm.

After the step 2, the lens 1 having the water-repellent antireflection film is taken out from the 2 nd film forming chamber. Then, the hydroxyl groups of the base film 5 and the waterproof film 6 are subjected to appropriate dehydration condensation reaction until a strong covalent bond is formed, and the film is stored in the atmosphere for a predetermined time.

In the method for producing a lens 1 having a water-repellent antireflection film according to embodiment 2 shown in fig. 3, only the above-described step 2 may be performed.

In the method for producing lens 1 having a waterproof antireflection film in the present embodiment, base film 5 and waterproof film 6 are formed while maintaining a reduced pressure in the same film forming chamber (2 nd film forming chamber) in which the substrate heating temperature is set to 250 ℃. Thereby, the cleanliness of the surface of the base film 5 can be increased, and a state with no binder can be maintained on the surface of the base film 5 when the waterproof film 6 is formed.

Here, the unbound substance reacts with the gas in the atmosphere at a moment when it is released into the atmosphere, and loses its binding property. That is, the antireflection film 4 formed in the 1 st film forming chamber through the 1 st process is exposed to the atmosphere when it is moved to another 2 nd film forming chamber in the 2 nd process. Therefore, the unbound electrons on the surface of the antireflection film 4 are bound to the gas component in the atmosphere, and the binding property is lost. In contrast, in the present embodiment, after the base film 5 is formed, the water-repellent film 6 is formed in the same film forming chamber as it is in a state of being kept depressurized. Thus, in the present embodiment, the base film 5 and the waterproofing film 6 are continuously formed under reduced pressure. Therefore, when the waterproof film 6 is formed, the surface of the base film 5 has a high bondability with unbound electrons.

In the present embodiment, the base film 5 has a high density of 70% to 100%, and can form a strong covalent bond with the waterproof film 6 in a state having high bondability with the unbound substance.

In the structure shown in fig. 2 in which the antireflection film 4, the base film 5, and the water-repellent film 6 are formed, as described above, it is necessary to form films in the 1 st step and the 2 nd step in separate film forming chambers. This is because the substrate heating temperature needs to be changed between the 1 st process and the 2 nd process. In the step 1, the substrate heating temperature must be high in order to increase the strength of the antireflection film 4. In the present embodiment, since the glass lens 2 is used on the substrate, durability against the substrate heating temperature is provided, and the substrate heating temperature is increased, so that the strength of the antireflection film 4 can be effectively increased. On the other hand, in the 2 nd step, in order to obtain good waterproof properties of the waterproof film 6, it is necessary to lower the substrate heating temperature to the substrate heating temperature in the 1 st step or to perform the heating at a normal temperature level without heating. At this time, since the 1 st film forming chamber which is the same as the 1 st process is used, it takes a long time to reduce the substrate heating temperature, which lowers the manufacturing efficiency. Therefore, in the present embodiment, by changing the film forming chamber during the transition from the 1 st process to the 2 nd process and lowering the substrate heating temperature of the 2 nd film forming chamber in the 2 nd process, good water-repellent characteristics can be obtained. As described above, with the excellent adhesion and durability of the waterproof film 6, the lens 1 having the waterproof antireflection film excellent in the antireflection effect and the waterproof effect can be manufactured.