CN100492056C - Optical article and manufacturing method thereof - Google Patents

Abstract

The present invention provides an optical article and a manufacturing method of the same. The object of the invention is to provide a manufacturing method for an optical article which can improve scratch resistance. The invention relates to the manufacturing method for the following optical article which has a function layer including at least one sub-layer, the function layer is formed on an optical substrate directly or with at least one different layer interposed between the layer and the optical substrate. The manufacturing method has a step of forming the function layer which includes a layer forming step and a nitrogen treatment step, the layer forming step is a step for forming one sub-layer included in the function layer by vacuum steam plating, and the nitrogen treatment step is a step for processing nitrogen treatment to the surface of the sub-layer obtained in the layer forming step.

Description

Optical article and manufacturing method thereof

technical field

The present invention relates to an optical article having a functional thin film (functional layer) such as an antireflection layer on an optical substrate made of glass or plastic, and a method for producing the same.

Background technique

In the process of manufacturing various optical articles, various functional films (functional layers) including hard coat layers, colored layers, antireflection layers, and antifouling layers are formed directly on optical substrates made of glass or resin or on the functional A primer layer is sandwiched between the film and the optical substrate. In addition, in the process of manufacturing spectacle lenses or other optical articles, an antireflection layer is formed directly on an optical substrate made of glass or resin or a hard coat layer is interposed between the antireflection layer and an optical substrate, or a primer layer is interposed And hard coating, so as to suppress light reflection and improve light transmission. One form of the antireflection layer is an antireflection layer having a multilayer structure formed by laminating a low-refractive-index sublayer and a high-refractive-index sublayer. Suitable materials for constituting the low refractive index sublayer include silicon oxide such as SiO ₂ or SiO _x , or MgF ₂ . Suitable materials for the high refractive index sublayer include ZrO ₂ , Ta ₂ O ₅ , TiO ₂ , CeO ₂ or Y ₂ O ₃ . The anti-reflection layer may also be a structure including Al ₂ O ₃ or CeF ₃ sub-layers with a medium refractive index.

In the formation of functional thin films and anti-reflective layers of multilayer structures, vacuum evaporation is often used, which is to heat and evaporate the substances constituting the thin film or the sublayers by means of electron gun or resistance heating under vacuum conditions. substances to be laminated on optical substrates.

Patent Document 1 discloses a film forming apparatus having three chambers, wherein the third chamber is used to form an antifouling layer on an antireflection layer. After placing the optical substrate in the first chamber, the antireflection film is vapor-deposited in the second chamber, and an antifouling layer is formed on the antireflection film in the third chamber.

In order to keep the surface which greatly affects the optical properties of the optical article in good condition, it is important to improve the durability, especially the scratch resistance, of the antireflection layer having a multilayer structure. In semiconductor optical components such as image sensors, a silicon nitride thin film is known as a substance having high durability and high light transmittance.

Patent Document 2 discloses that a silicon nitride thin film is formed by irradiating a substrate with nitrogen ions simultaneously with vacuum deposition of silicon, or by alternately performing vacuum deposition of silicon and irradiation of nitrogen ions. The silicon nitride layer has excellent light transmittance, therefore, the silicon nitride layer can be used as one of the sublayers of the anti-reflection layer with a multi-layer structure. As an antireflection layer, in order to obtain a desired optical effect, it is necessary to form a homogeneous layer with a predetermined thickness. However, it is difficult to stably form a silicon nitride layer. Therefore, in the method disclosed in Patent Document 2, it is required to precisely control the vapor deposition rate of silicon and the irradiation amount of nitrogen ions.

Patent Document 1: JP-A-2005-187936

Patent Document 2: Japanese Unexamined Patent Publication No. 5-214515

In addition, some optical designs of anti-reflection layers have been carried out by using low-refractive-index layers and high-refractive-index layers having the above-mentioned composition, so that an optical system with high transmittance can be obtained by such design. However, the refractive index of the silicon nitride layer is different from that of the layer having the above composition. The silicon nitride layer basically has a high refractive index, but its refractive index is different from that of other layers with a high refractive index, and therefore, it is necessary to design a new optical system.

Also, when a silicon nitride layer is used as the high refractive index layer, it is presumed that the interface portion between the silicon nitride layer and the silicon dioxide layer serving as the low refractive index layer will be in a composition state of _SiONx . It is difficult to control the refractive index of the layer including the interface portion and the film thickness corresponding to the refractive index. For example, Si ₃ N ₄ has a high refractive index of about 2.05, but if a Si ₃ N ₄ layer exists together with SiN _x O _y and SiO ₂ , the refractive index is in the range of 1.45 to 2.05. It is considered that the durability of the antireflection layer composed of the silicon nitride sublayer and the silicon dioxide sublayer is greatly improved. However, it is difficult to manufacture an antireflection layer having sufficient optical properties.

In addition, in order to keep the surface that greatly affects the optical properties of the optical article in good condition, it is very important to design a functional film for improving durability, especially scratch resistance. In semiconductor optical components such as image sensors, a silicon nitride thin film is known as a substance having high durability and high light transmittance.

Silicon dioxide thin films are typically formed on optical substrates alone or as part of a multilayer film. Especially when the optical substrate is a resin, the weak scratch resistance of the silica thin film also affects the durability of the optical substrate.

The silicon nitride film improves the scratch resistance of the silicon dioxide film. Patent Document 2 discloses that a silicon nitride thin film is formed by irradiating a substrate with nitrogen ions simultaneously with vacuum deposition of silicon, or by alternately performing vacuum deposition of silicon and irradiation of nitrogen ions. However, it is difficult to stably form a silicon nitride thin film. In the method disclosed in Patent Document 2, it is required to precisely control the vapor deposition rate of silicon and the irradiation amount of nitrogen ions.

Contents of the invention

One aspect of the invention is to provide an optical article comprising the optical article. The optical article has a layer comprising a nitriding-treated portion which is the surface of the layer on the side facing away from the optical substrate, the layer having _SiOx as a main component and being formed directly on the optical substrate At least one other layer is sandwiched on or between said layer and said optical substrate.

Since the optical article contains a nitrided part of the layer, which is the surface of the layer on the side facing away from the optical substrate, if such an optical article is used, it is possible to make the layer containing the nitrogenated part The durability, especially the scratch resistance of the layer of the chemically treated part is improved.

In this optical article, the main component of the nitrided portion is Si _s O _{t Nu} (s>0, t≧0, u>0).

As a form of such an optical article, it has an antireflection layer and an antifouling layer formed directly on the antireflection layer, and the antireflection layer is formed directly on the optical substrate or between the antireflection layer and the optical substrate. At least one other layer is sandwiched therebetween. The antireflection layer includes two or more sublayers, and among the two or more sublayers, except for the outermost layer of the antireflection layer, at least one of the sublayers is the above-mentioned layer containing the portion subjected to nitriding treatment .

As a form of this anti-reflection layer, it comprises two or more low-refractive-index sublayers and at least one high-refractive-index sublayer sandwiched between the two or more low-refractive-index sublayers, and the two One of the low-refractive-index sublayers is the outermost layer, and one of the other layers of the two or more low-refractive-index sublayers is the layer including the nitriding-treated portion.

As another form of the optical article, it has an anti-reflection layer, and the anti-reflection layer is directly formed on the optical substrate or at least one other layer is sandwiched between the anti-reflection layer and the optical substrate. The antireflection layer includes two or more sublayers, and among the two or more sublayers, at least the outermost layer is the layer including the portion subjected to nitriding treatment.

Another aspect of the present invention is to provide a method of manufacturing an optical article, the optical article has a functional layer, the functional layer is directly formed on the optical substrate or at least one other layer is sandwiched between the functional layer and the optical substrate and The functional layer contains at least one sublayer.

The functional layer mentioned here refers to a film with specific functions, and the film includes an anti-reflection layer, an optical filter such as a low-pass filter, a high-pass filter and a band-pass filter, etc., and a hard film.

The manufacturing method of this optical article has the process of forming a functional layer. The process of forming a functional layer includes a layer forming process and a nitriding treatment process, the layer forming process is a process of forming a sub-layer by vacuum evaporation, and the nitriding treatment process is the process of forming a layer in the layer forming process The resulting surface including one sublayer is subjected to a nitriding process.

In the manufacturing method of the optical article, it is preferable to perform (include) the steps of introducing a gas containing nitrogen gas into a vacuum chamber in which the layer forming step is performed, and performing plasma treatment or ion gun treatment in the nitriding treatment step.

Description of drawings

FIG. 1 is a schematic diagram showing a general configuration of an apparatus for forming an antireflection layer.

FIG. 2 is a flowchart showing a method of manufacturing a lens according to the first embodiment.

Fig. 3 is an enlarged cross-sectional view showing a schematic structure of an antireflection layer.

Fig. 4 is a schematic diagram showing a schematic configuration of an apparatus for forming an antireflection layer and an antifouling layer.

FIG. 5 is a flowchart showing a method of manufacturing a lens according to the second embodiment.

Fig. 6 is an enlarged cross-sectional view showing a general structure of an antireflection layer and an antifouling layer.

Fig. 7 is a schematic diagram showing a general configuration of an apparatus for forming a functional thin film and an antifouling layer.

FIG. 8 shows a flowchart of the lens manufacturing method according to the third embodiment.

Fig. 9 is an enlarged cross-sectional view showing a schematic structure of a functional film.

Symbol Description

1 Optical substrate (plastic lens, 1a lens, 1b lens, 1c lens)

2 hard coat

3 anti-reflection layer (functional layer)

4 antifouling layer

10a, 10b and 10c Optical articles

30 (low refractive index) thin film, 31~34 sublayer, 35 uppermost layer (outermost layer, sublayer), 39 (nitride-containing) partial layer

40 workpiece substrate (substrate)

50 film forming device, 52, 53 and 54 vacuum generating device (52a rotary pump, 52b roots pump, 52c cryopump; 53a rotary pump, 53b roots pump, 53c cryopump; 54a rotary pump, 54b roots pump, 54c turbomolecular pump), 55 AR evaporation source [55a AR evaporation source (low refractive index material), 55b AR evaporation source (high refractive index material)], 56 electron gun, 57 shutter, 59a antifouling layer evaporation source, 59b antifouling layer evaporation source

60 plasma generator (RF coil), 61 matching box, 62 high frequency oscillator, 63 oxygen, 64a nitrogen, 64b argon, 65 automatic pressure regulator, 66 mass flow controller, 67 compensation plate, 68 heater, 69 mass flow controller

70 ion gun, 71 DC power supply, 72 RF power supply

80 support device, 81 arch cover

Detailed ways

(first embodiment)

One mode of the first embodiment of the present invention relates to a method of manufacturing an optical article, the manufacturing method including the step of forming an antireflection layer having a multilayer structure, the antireflection layer including at least one layer composed of silicon dioxide sublayer, and the anti-reflection layer is directly formed on the optical substrate or at least one other layer is sandwiched between the anti-reflection layer and the optical substrate. The process of forming the anti-reflection layer includes a layer forming process and a nitriding process, the layer forming process is a process of forming at least one sublayer made of silicon dioxide by vacuum evaporation, and the nitriding process is formed by vacuum evaporation. A process of nitriding the surface of at least one sub-layer composed of silicon dioxide.

Here, the sublayers mentioned in the present application refer to the individual layers constituting the antireflection layer or functional layer of the multilayer structure. Specifically, the sub-layer refers to a low-refractive-index sub-layer composed of _{SiO 2} or SiO _x and other silicon oxides, or MgF ₂ and other materials, and is composed of ZrO ₂ , Ta ₂ O ₅ , TiO _{2 ,} CeO ₂ A high-refractive-index sublayer made of materials such as Al ₂ O ₃ or CeF 3 and a medium-refractive index sub-layer made of materials such as Al 2 O 3 or CeF ₃ .

In the manufacturing method of the present optical article, the one or more sublayers composed of silicon dioxide evaporated in vacuum are subjected to nitriding treatment, instead of using the silicon nitride layer as a single sublayer in the multilayer structure . That is, the surface of the sublayer made of silicon dioxide is partially nitrided to obtain the effect of silicon nitride.

In the nitriding treatment process, a gas containing nitrogen gas is introduced into a vacuum chamber in which the layer formation process is performed, and plasma treatment or ion gun treatment is performed. The purpose of the nitriding treatment in this manufacturing method is to partially or completely nitride the surface of a sublayer made of silicon dioxide formed in the layer forming step. Therefore, it is not necessary to strictly control the film thickness. In addition, silicon nitride can be easily introduced into the antireflection layer of the multilayer structure even if the timing of controlling the ion current is not accurately grasped. The scratch resistance of the antireflection layer can be improved by introducing silicon nitride. In particular, in the plasma treatment, silicon nitride can be easily introduced into an apparatus for vacuum evaporation or during the evaporation process without using an ion source.

Other modes of the first embodiment of the present invention relate to an optical article having an antireflection layer formed directly on an optical substrate or with at least one other layer sandwiched between the antireflection layer and the optical substrate . The antireflection layer has a multilayer structure including at least one sublayer composed of silicon dioxide, and the surface of the at least one sublayer composed of silicon dioxide on the side facing away from the optical substrate is nitrided.

In addition, in another form of the first embodiment of the present invention, at least one sublayer made of silicon dioxide in the antireflection layer of the optical article has a nitrogen-containing partial layer formed on the back surface. on the surface facing the optical substrate side. Here, the partial layer in this application refers to the surface layer part of the sublayer composed of silicon dioxide. The invention relates to the nitriding treatment of the surface portion of such at least one sublayer of silicon dioxide. That is, at least one sublayer made of silicon dioxide is a layer including a nitrided portion (surface layer nitrided layer).

Nitrogen-containing sublayers are formed on the side of at least one sublayer composed of silicon dioxide facing away from the optical substrate by nitriding the sublayer composed of silicon dioxide. Therefore, since the scratch-prone surface of the antireflection layer is silicon nitrided, its scratch resistance can be improved.

Some layers contain Si _s O _{t Nu} (s and u are positive numbers, and t is a number greater than or equal to 0). After nitriding the sublayer made of silicon dioxide, a silicon nitride-containing region is partially or completely formed on the surface of the sublayer, thereby improving scratch resistance. In addition, the thickness and/or area of the partial layer formed by the nitriding treatment is limited, therefore, the partial layer as a sublayer can maintain the optical performance of silicon dioxide, thereby requiring little modification in the film design of the anti-reflection layer. Change. In addition, the scratch resistance is improved due to the presence of silicon nitride, and at the same time, the characteristics of the sublayer composed of silicon dioxide, that is, the adhesion between the substrate and the upper layer can be effectively utilized.

In the optical article according to the first embodiment of the present invention, it is preferable that at least one sublayer made of silicon dioxide subjected to the nitriding treatment is the layer farthest from the optical substrate in the antireflection layer. In addition, in the optical article according to the first embodiment of the present invention, at least one of the nitrogen-containing partial layers is preferably the outermost layer of the antireflection layer. The nitrided at least one sublayer of silicon dioxide may be any layer in the multilayer structure, and the nitriding treatment of said sublayer contributes to improving the scratch resistance of the antireflection layer. Considering that it is the uppermost layer, that is, the sublayer forming the surface on the side facing away from the optical substrate, which is most susceptible to scratches, it is preferable to nitride the sublayer.

What Fig. 1 represented is to be used for forming the film-forming device 50 structure schematic diagram of anti-reflection layer 3 with multilayer structure, and this anti-reflection layer 3 is to be placed on the substrate (workpiece) 40 on support device 80 by vacuum evaporation formed on the surface. The supporting device 80 has a disc-shaped arched cover 81 protruding above, on which a plurality of workpiece substrates (optical substrates, specifically lens substrates) 40 are arranged concentrically on the arched cover 81, while making the arched The cover 81 forms a film on the workpiece substrate 40 while rotating. The film forming apparatus 50 has three chambers CH1, CH2, and CH3 through which the supporting apparatus 80 can pass. The respective chambers CH1 to CH3 can be mutually sealed, and the internal pressures of the respective chambers CH1 to CH3 are controlled by vacuum generating devices 52 , 53 and 54 , respectively.

The chamber CH1 is an entrance or gate chamber, and after being introduced into the support device 80 from the outside, degassing is performed by keeping the inside of the chamber CH1 at a constant pressure or lower for a certain period of time. The chamber CH1 is equipped with a vacuum generating device 52 having a rotary pump 52a, a roots pump 52b and a cryopump 52c.

Chamber CH2 is the second chamber for forming an antireflection layer (AR layer). Therefore, AR vapor deposition sources 55a and 55b, an electron gun 56 for vaporizing the AR vapor deposition source 55, and an openable and closable switch 57 for adjusting the vapor deposition amount are provided inside the chamber CH2. The antireflection layer has a structure in which a low-refractive-index sublayer composed mainly of silica and a high-refractive-index sublayer composed of other compositions having, for example, One composition or two or more compositions among TiO ₂ , Nb ₂ O ₃ , Ta ₂ O ₅ , and ZrO ₂ . Therefore, at least two vapor deposition sources 55a and 55b and an electron gun 56 for heating and melting the vapor deposition sources 55a and 55b are provided in the chamber CH2. The chamber CH2 is maintained at an appropriate pressure by a vacuum generator 53 having a rotary pump 53a, a Roots pump 53b, and a cryopump 53c.

In addition, a mass flow controller 66 for controlling the indoor atmosphere is connected to the chamber CH2. The oxygen supply source 63 and the nitrogen supply source 64a are connected to the mass flow controller 66, so that the atmosphere in the chamber CH2 can be controlled to be 100% oxygen or 100% nitrogen, or a mixture of oxygen and nitrogen in proper proportion.

In addition, an RF coil 60 for generating high-frequency plasma is provided inside the chamber CH2. By connecting the RF coil 60 and the high-frequency oscillator 62 through the matching box 61, plasma having a predetermined output power is generated at a predetermined frequency in the chamber CH2.

In addition, an ion gun 70 is provided inside the chamber CH2. The ion gun 70 is connected to a DC power source 71 and an RF power source 72 , and can irradiate the workpiece substrate 40 placed on the supporting device 80 with ions of predetermined energy. The oxygen gas supply source 63 and the nitrogen gas supply source 64 a are connected to the ion gun 70 through the mass flow controller 69 , so that the ion gun 70 can irradiate the workpiece substrate 40 with oxygen ions or nitrogen ions.

The chamber CH3 is a chamber for taking out. The support device 80 on which the workpiece substrate 40 with one side of the antireflection layer is placed is moved from the chamber CH2 to the chamber CH3, and then the workpiece substrate 40 is turned over, and then returned to the chamber CH2 again. Next, after the antireflection layer is formed on the other surface of the workpiece substrate 40, the support device 80 is returned to the chamber CH3, and the pressure of the chamber CH3 is returned to atmospheric pressure, and the support device 80 is taken out. Chamber CH3 is maintained at an appropriate pressure by a vacuum generator 54 having a rotary pump 54a, a Roots pump 54b and a turbomolecular pump 54c. The workpiece substrate 40 taken out from the chamber CH3 together with the supporting device 80 is placed in a constant temperature and humidity chamber (not shown in the figure) to be annealed in an atmosphere of appropriate humidity and temperature. Furthermore, the workpiece substrate 40 is aged by leaving it in a room for a predetermined time.

By using the plasma generator (RF coil) 60 or the ion gun 70 provided in the chamber CH2, the film formation device 50 can perform nitriding treatment on the low-refractive index sublayer mainly composed of silicon dioxide. The atmosphere in the chamber CH2 is adjusted to a nitrogen atmosphere or a mixed atmosphere of nitrogen and oxygen using the automatic pressure regulator 65, and then, plasma is generated by the RF coil 60, thereby irradiating the sublayer made of silicon dioxide with nitrogen. ions, thereby enabling the sublayer to be nitrided. The atmosphere in chamber CH2 can also be nitrogen-argon or nitrogen-oxygen-argon. In addition, by irradiating the workpiece substrate 40 with nitrogen ions using the ion gun 70 , the surface of the sublayer made of silicon dioxide can be nitrided.

It is very difficult to form a sublayer composed of silicon nitride by vacuum evaporation. However, it is relatively easy to form nitrides on the surface by plasma treatment or ion gun treatment of silicon oxide. In this case, nitrogen and silicon compounds other than Si ₃ N ₄ such as Si _s O _{t Nu} (s, u are positive integers, t is an integer greater than 0) and SiO ₂ are formed on the surface. mixture. That is, since the nitride-containing partial layer is formed in a state of covering the surface of the sublayer made of silicon dioxide entirely or partially, the durability of the covered portion is improved. In addition, since the nitride-containing partial layer is formed only on the outermost layer of the sublayer made of silicon dioxide, it hardly affects the film design of the antireflection layer.

In FIG. 2 , the process of forming an anti-reflection layer having a multi-layer structure on the workpiece substrate 40 in the film forming device 50 is shown in a flow chart. In addition, FIG. 3 is a cross-sectional view showing the film structure (layer structure) of the optical article 10 a of the present embodiment including the antireflection layer 3 .

As an example of the antireflection layer 3, it includes a first sublayer 31 formed on the substrate 1 formed of silicon oxide, a second sublayer 32 formed of zirconium oxide, a third sublayer 33 formed of silicon oxide, The fourth sublayer 34 is composed of zirconia, and the fifth sublayer 35 is composed of silicon oxide.

When the optical substrate (substrate) 1 is plastic, in step 11, before forming the antireflection layer 3, a hard coat layer 2 is first formed on the optical substrate 1. In order to improve the adhesion between the hard coat layer 2 and the substrate 1, a primer layer may be formed between the hard coat layer 2 and the substrate 1 in some cases. The hard coat 2 imparts scratch resistance to the plastic lens 1 . Simultaneously because the hard coating 2 exists between the plastic lens 1 and the anti-reflection layer 3, there is good adhesion between the anti-reflection layer 3 and the plastic lens 1, and has the function of preventing the anti-reflection layer 3 from the plastic lens 1. Stripped features. Therefore, even if the antireflection layer 3 is not highly adhesive to the plastic lens 1 , the presence of the hard coat layer 2 can improve the adhesion between the plastic lens 1 and the antireflection layer 3 .

As a method for forming the hard coat layer 2, a method of applying a curable composition capable of forming the hard coat layer 2 on the surface of the plastic lens 1 and curing the coating film is generally employed. When the plastic lens 1 is a thermoplastic resin, it is preferable to use electromagnetic waves such as ultraviolet rays or ionizing radiation such as electron beams to cure the coating film instead of thermal curing to cure the coating film.

For example, a thermosetting composition containing inorganic fine particles. The composition comprises a silicone compound that generates silanol groups by ultraviolet irradiation and a photocurable silicone composition mainly composed of organopolysiloxane that has the ability to condense with silanol groups. Reactive halogen atoms and reactive groups such as amino groups. In addition, the curable composition containing inorganic fine particles contains an acrylic ultraviolet curable monomer composition such as UK-6074 manufactured by Mitsubishi Rayon Co., Ltd. and inorganic fine particles such as _SiO2 or _TiO2 with a particle diameter of 1 nm to 100 nm. . In addition, the curable composition containing inorganic fine particles is obtained by dispersing a photocurable silicon composition, an acrylic ultraviolet curable monomer composition, and inorganic fine particles in a silane compound or an organosilane coupling agent, and the silane compound Alternatively, the silane coupling agent has a polymerizable group such as a vinyl group, an allyl group, an acryloxy group, or a methacryloxy group, and a hydrolyzable group such as a methoxy group.

As a method for forming the coating film of the hard coat layer 2, a method such as a dipping method, a spin coating method, a spray coating method, a flow method, or a doctor blade method can be used. In addition, in order to improve the adhesion, it is preferable to subject the surface of the plastic lens 1 to a surface treatment using high-voltage discharge such as corona discharge or microwave before forming a coating film. The formed coating film is cured by methods such as heating, ultraviolet rays or electron beams, so as to obtain the hard coat layer 2 .

The substrate 1 on which the hard-coat layer 2 was formed is fixed on the support device 80 as a workpiece substrate 40 and transported to the film forming device 50 . In the film forming apparatus 50, first, the support device 80 is introduced into the chamber CH1, and degassed, and then the support device 80 is moved into the chamber CH2, and the plasma treatment in step 12 is performed. In step 13, the first sublayer 31 made of silicon oxide is formed (layer formation step), and then, in step 14, the surface of the sublayer 31 is nitrided by plasma treatment or ion gun treatment (nitriding treatment step) . In this way, the nitride-containing partial layer 39 is formed on the surface (the surface facing away from the substrate 1 ) of the sublayer 31 made of silicon oxide, covering the whole or part of the surface. At this time, a gas of any composition containing nitrogen can be used as the introduction gas, for example, 100% nitrogen, a mixed gas of nitrogen and oxygen, a mixed gas of nitrogen and argon, or a mixed gas of nitrogen, oxygen and argon Wait for gas.

After forming the second sublayer 32 made of zirconia in step 15 , the third sublayer 33 made of silicon oxide is formed in step 16 . Then, in step 17, the surface is nitrided in the same manner as in step 14. In step 15 and step 16, the second sublayer 32 with a high refractive index and the third sublayer 33 with a low refractive index are successively formed. Thereafter, by the nitriding treatment in step 17, the surface of the third sublayer 33 with a low refractive index formed later can be nitrided. That is, by successively performing the layer forming step in step 16 and the nitriding treatment step in step 17, the surface of the sublayer formed in the layer forming step can be nitrided. If step 15 and step 16 are combined into one layer forming process, then in step 17, the surface of the sub-layer formed before the nitriding treatment can be nitrided.

After forming the fourth sublayer 34 of zirconia in step 18 , the fifth sublayer 35 of silicon oxide is formed in step 19 . In step 20, the surface is nitrided in the same manner as in step 14. In this way, an antireflection layer 3 with a five-layer structure is formed on one side of the optical article, so, in step 21, the substrate 40 is turned over and fixed on the support device 80, and steps 12 to 20 are repeated to form an antireflection layer 3 with a multilayer structure. Layer 3. When the antireflection layer 3 is formed on both surfaces of the substrate 40 , the substrate 1 (work substrate 40 ) is taken out in step 22 .

Here, there are three silicon oxide sublayers 31 , 33 and 35 , and only the uppermost sublayer 35 can be nitridated, or any two layers including the uppermost sublayer 35 can be nitridated. Since only the extremely thin surface of the silicon oxide sublayer is nitrided in the above-mentioned nitriding treatment, the performance as the antireflection layer 3 is hardly affected.

(Embodiment 1-1)

Hereinafter, according to the manufacturing method shown in FIG. 2 , several embodiments of manufacturing plastic spectacle lenses as optical articles will be described. In each of the following Examples and Comparative Examples, a plastic lens substrate for eyeglasses (manufactured by Seiko Epson Co., trade name: Seiko Supper Sovereign) was used as the optical substrate 1 . In step 11 , hard coat layers 2 are formed on both surfaces of the optical substrate 1 . In subsequent steps, the optical substrate 1 on which the hard coat layer 2 is formed is used as the workpiece substrate 40, and the antireflection layer 3 is formed thereon.

The workpiece substrate 40 is fixed on the dome cover 81 of the supporting device 80 with the concave surface facing down, and then transported to the film forming device 50 . In step 12, after degassing in the chamber CH1, introduce 100% argon gas into the chamber CH2, and control the gas pressure to 4.0×10 ^-2 Pa, while using the plasma generated by the high-frequency plasma generator to treat the workpiece substrate 40 for processing. Plasma treatment was performed for 1 minute under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 400 W. The purpose of this treatment is to clean the surface of the substrate, thereby improving the adhesion between the substrate 1 and the antireflection layer 3 .

Steps 13 to 20 are then carried out to alternately vapor-deposit SiO ₂ sublayers 31 , 33 and 35 and ZrO ₂ sublayers 32 and 34 , thereby forming the antireflection layer 3 composed of these sublayers. The film thickness of each layer was adjusted so that the film thickness of the first sublayer (SiO ₂ ) 31 was 0.09λ, the film thickness of the second sublayer (ZrO ₂ ) 32 was 0.16λ, and the film thickness of the third sublayer (SiO ₂ ) 33 The thickness of the film is 0.05λ, the thickness of the fourth sublayer (ZrO ₂ ) 34 is 0.27λ, and the thickness of the fifth sublayer (SiO ₂ ) 35 is 0.27λ.

The uppermost layer 35 of the antireflection layer 3 is a SiO ₂ layer. The plasma generation device 60 is used in the nitriding treatment in steps 14, 17 and 20. Therefore, after evaporating the _SiO2 layer, nitrogen and oxygen gas were introduced into the chamber at a ratio of 7:3, and a high-frequency plasma generator was used to generate plasma while controlling the gas pressure to 4.0×10 ^-2 Pa. Plasma treatment was performed for 5 minutes under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 600 W. In this way, the nitride-containing partial layer 39 is formed on the SiO ₂ layer surfaces of the first sublayer 31 , the third sublayer 33 , and the fifth sublayer 35 . That is, the first sublayer 31 , the third sublayer 33 , and the fifth sublayer 35 are layers including nitrided portions (surface nitriding layers).

Then, in step 21, the supporting device 80 is moved to the chamber CH3, and the supporting device 80 is taken out from the chamber, and the flipped lens is fixed on the arched cover 81 of the supporting device 80 with the convex side downward, and then the same process as above is carried out . Then, at step 22, the workpiece substrate 40 is taken out of the chamber CH3. In this way, a plastic lens (sample S1-1) having antireflection layers 3 on both surfaces of the workpiece substrate 40 (lens base 1) was produced. That is, the antireflection layer 3 is also provided on the reverse side of the substrate 1 having the hard coat layer 2 . In sample S1-1, the surfaces of the silicon dioxide sublayers 31 , 33 and 35 of the antireflection layer 3 were nitrided, ie the surface facing away from the substrate 1 was nitrided.

(Embodiment 1-2)

In Example 1-2, steps 14 and 17 were not carried out, and the others were the same as in Example 1-1, and a plastic lens (sample S1-2) having an antireflection layer 3 composed of 5 layers was manufactured. Therefore, in the sample S1-2 of this embodiment 1-2, among the silicon dioxide sublayers 31, 33 and 35 included in the antireflection layer 3, only the outermost (fifth layer) sublayer 35 (i.e. The sublayer 35 of the anti-reflection layer 3 formed on the side facing away from the optical substrate 1 is subjected to nitriding treatment to form a nitride-containing partial layer 39 .

(Embodiment 1-3)

In Example 1-3, step 14 was not carried out, and the others were the same as in Example 1-1, and a plastic lens (sample S1-3) having an antireflection layer 3 composed of 5 layers was manufactured. Therefore, in the sample S1-3 of this Example 1-3, in the silicon dioxide sublayers 31, 33, and 35 included in the antireflection layer 3, only the 3rd sublayer 33 and the 5th sublayer 35 were treated. Nitriding treatment forms the nitride-containing partial layer 39 .

(Embodiment 1-4)

In Example 1-4, step 17 was not carried out, and the others were the same as in Example 1-1, and a plastic lens (sample S1-4) having an antireflection layer 3 composed of 5 layers was manufactured. Therefore, in the sample S1-4 of this Example 1-4, in the silicon dioxide sublayers 31, 33 and 35 included in the antireflection layer 3, only the first sublayer 31 and the fifth sublayer 35 were treated. Nitriding treatment forms the nitride-containing partial layer 39 .

(Embodiment 1-5)

In Examples 1-5, steps 12-20 are carried out, and all the silicon dioxide sublayers 31 , 33 and 35 included in the antireflection layer 3 are subjected to nitriding treatment. However, in the nitriding process of steps 14, 17 and 20, the ion gun 70 is used instead of the plasma generating device 60. Therefore, the nitrogen gas 64a and the oxygen gas 63 are introduced into the ion gun 70 at a ratio of 7:3, the flow rate is controlled to be 35 SCCM, and ions are irradiated to the sublayers 31 , 33 and 35 . Ion irradiation was performed for 5 minutes under the conditions of ion irradiation at a frequency of 13.56MHz, RF power of 450W, accelerating voltage of 500V, and suppressing voltage of 300V while controlling the chamber pressure at the time of treatment to 4×10 ^-3 Pa. . Others are the same as in Example 1-1.

Therefore, in the sample S1-5 of this embodiment 1-5, all of the silicon dioxide sublayers 31, 33, and 35 included in the antireflection layer 3 are subjected to nitriding treatment to form the nitride-containing partial layer 39.

(Embodiment 1-6)

In Examples 1-6, a lens having an antireflection layer 3 composed of a 7-layer structure was produced. Therefore, a step of vapor-depositing the sixth sublayer, a step of vapor-depositing silicon dioxide as the seventh sublayer as the outermost layer, and a step of nitriding the silicon dioxide in the outermost layer were added. In addition, TiO ₂ is used instead of ZrO ₂ when forming the high refractive index sublayer. Others are the same as in Example 1-1.

In these steps of forming the high refractive index sublayer, TiO ₂ is deposited by ion accelerator deposition (ion assist deposition). Regarding the ion irradiation conditions at this time, 100% oxygen with a flow rate of 35 SCCM was introduced into the ion gun 70, the frequency was adjusted to 13.56 MHz, the RF power was 450 W, the acceleration voltage was 500 V, and the suppression voltage was 300 V. The pressure in the chamber during the treatment was 4×10 ^-3 Pa. In this case, the thickness of the first sublayer (SiO ₂ ) is 0.08λ, the thickness of the second sublayer (TiO ₂ ) is 0.07λ, the thickness of the third sublayer (SiO ₂ ) is 0.10λ, and the thickness of the fourth The thickness of the sublayer (TiO ₂ ) is 0.18λ, the thickness of the fifth sublayer (SiO ₂ ) is 0.07λ, the thickness of the sixth sublayer (TiO ₂ ) is 0.14λ, and the thickness of the seventh sublayer (SiO ₂ ) has a film thickness of 0.26λ.

Therefore, in the sample S1-6 of this embodiment 1-6, the nitride-containing partial layer 39 is formed on all the silicon dioxide sublayers included in the antireflection layer 3 .

(Comparative example 1-1)

In Comparative Example 1-1, steps 14, 17, and 20 were not carried out, and a plastic lens (sample SR1-1) having the same composition as that of Example 1-1 without nitriding treatment was produced, that is, the plastic lens had The anti-reflection layer 3 with a 5-layer structure composed of a low refractive index SiO ₂ sublayer and a high refractive index ZrO ₂ sublayer. Others are the same as in Example 1-1. Therefore, in the sample SR1-1 of the comparative example 1-1, all of the silicon dioxide sublayers 31 , 33 and 35 included in the antireflection layer 3 were not subjected to nitriding treatment.

(Comparative example 1-2)

In Comparative Example 1-2, a plastic lens (sample SR1-2) having the same composition as Example 1-6 without nitriding treatment was produced, that is, the plastic lens had a _SiO2 sublayer with a low refractive index The anti-reflection layer 3 with a 7-layer structure composed of TiO ₂ sublayers with high refractive index. Other is identical with embodiment 1-6. Therefore, in the sample SR1-2 of Comparative Example 1-2, the nitriding treatment was not performed on all the silicon dioxide sublayers included in the antireflection layer 3 .

(evaluate)

The scratch resistance of samples S1-1 to S1-6, SR1-1 and SR1-2 produced in Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2 were evaluated by the following method. The evaluation results are summarized in Table 1. Steel wool (#0000) wrapped around the jig reciprocated 50 times on the outermost surface of the antireflection layer 3 of each of the samples S1-1 to S1-6, SR1-1 and SR1-2 under a load of 2 kg. The degree of abrasion thus produced was compared with the standard sample and evaluated in four grades of A, B, C and D. Among them, A represents the best, and B, C, and D represent the deterioration in sequence.

Table 1

In samples S1-1 to S1-6 of Examples 1-1 to 1-6, at least one silicon dioxide sublayer was subjected to nitriding treatment. The evaluation of the scratch resistance test of these samples S1-1 to S1-6 was good (A). On the other hand, the evaluation of the scratch resistance test of samples SR1-1 and SR1-2 of Comparative Example 1-1 and Comparative Example 1-2 which were not subjected to nitriding treatment was poor (D).

When comprehensively evaluated, all samples S1-1 to S1-6 of Examples were ⊚ (excellent) as products. All samples SR1-1 to SR1-2 of the comparative example were x (failure). The results show that scratch resistance can be improved by nitriding at least one silicon dioxide sublayer.

In addition, although not clearly shown in Table 1 (Evaluation Results), compared with the samples of Examples 1-1, 1-5, and 1-6 in which all silicon dioxide sublayers were nitrided, only the The samples of Examples 1-2, 1-3 and 1-4 in which the uppermost layer and any two layers containing the uppermost layer were nitrided had slightly poorer scratch resistance, although their scratch resistance grades were also good (A ). However, the difference is within a completely permissible range.

In addition, the first embodiment (example) described above relates to an optical article in which an antireflection layer is formed on a plastic spectacle lens having a hard coat layer. For an optical article with a glass substrate, an antireflection layer can be formed on the substrate without a hard coating interposed between the substrate and the antireflection layer, and the above-mentioned embodiments can also be applied to an optical article with a glass substrate. Published method of manufacture. In addition, the optical article is not limited to spectacle lenses, but includes optical elements such as optical elements of image display devices, prisms, optical fibers, elements for information recording media, and optical filters, and the above-described embodiments can also be applied to these optical articles. The disclosed manufacturing method.

(second embodiment)

A layer (anti-fouling layer) having an anti-fouling function such as water resistance is often formed on optical articles used in daily life such as spectacle lenses. One of the purposes of the antifouling layer is to suppress the decrease in optical performance due to contamination of the surface with grease or the like. The most suitable composition for forming an antifouling layer is a fluorine-containing silane compound. The antifouling layer formed from the fluorine-containing silane compound has high waterproof performance and high antifouling performance. In addition, when silicon oxide is used as the uppermost layer of the antireflection layer, the antifouling layer formed of a fluorine-containing silane compound has the advantages of high adhesion to the surface of the antireflection layer and high durability. This may be due to the formation of siloxane bonds between the antireflection layer and the antifouling layer through the oxygen atoms on the surface of the antireflection layer.

On the other hand, if a silicon nitride layer is used as the uppermost layer of the antireflection layer instead of the silicon oxide layer, it is difficult to form a siloxane bond, and the durability of the antifouling layer tends to decrease. Therefore, if the silicon nitride layer exists in the uppermost layer of the antireflection layer, the reaction of the uppermost layer of the antireflection layer and the antifouling layer formed on the silicon nitride layer is hindered, thereby reducing the durability of the antifouling layer. The problem.

One form of the second embodiment of the present invention relates to a manufacturing method of an optical article, the manufacturing method including the steps of forming an antireflection layer and an antifouling layer, the antireflection layer is directly formed on an optical substrate or the antireflection layer At least one other layer is sandwiched between the layer and the substrate, and the antireflection layer has a multilayer structure including two or more low-refractive-index sublayers and at least one high-refractive-index sublayer. The process of forming the anti-reflection layer and the anti-fouling layer includes the following processes: the first process of forming the first low refractive index sub-layer, the nitriding treatment process of the surface of the first low refractive index sub-layer, and the first low refractive index sub-layer. The second process of forming the second low refractive index sublayer on the surface of the sublayer facing away from the optical substrate, and at least one high refractive index sublayer is sandwiched between the two, and the second low refractive index sublayer The process of directly forming an antifouling layer on the surface facing away from the optical substrate.

The sublayers described here are the same as described in the first embodiment. In the manufacturing method of the optical article, nitriding treatment is performed on the low-refractive index sublayer made of silicon dioxide or the like, instead of using silicon nitride as a single sublayer of the multilayer structure. That is, the surface of the low-refractive index sublayer is partially nitrided, whereby the effect of improving the film strength is obtained. In this manufacturing method, since the layer structure of the anti-reflection layer with silicon dioxide as the low refractive index sub-layer can be maintained, there are advantages brought by nitriding, so it is possible to choose, for example, not to laminate an anti-fouling layer. The second low-refractive-index sublayer is nitrided, and therefore, the durability of the anti-fouling layer is also ensured in the system in which the anti-fouling layer is laminated on the anti-reflection layer.

Therefore, in the first step and the second step, it is preferable to form the first low-refractive index sublayer and the second low-refractive index sublayer from silicon dioxide.

In addition, in this manufacturing method, in the first step, the first low-refractive-index sublayer is formed by vacuum evaporation, and in the nitriding treatment step, a gas containing nitrogen gas is introduced into a vacuum chamber in which the first step is performed, and by this The gas is subjected to plasma treatment or ion gun treatment so that the surface of the low-refractive index sublayer formed of silicon dioxide or the like can be partially or completely nitrided. Therefore, it is not necessary to strictly control the film thickness for the introduction of the nitrided layer, and the nitrided film can be easily introduced into the antireflection layer of the multilayer structure even without controlling the ion current or grasping the time with high precision, Thereby, the scratch resistance of the antireflection layer can be improved. In particular, in plasma treatment, silicon nitride can be easily introduced into an apparatus for vacuum evaporation or during the evaporation process without requiring an ion source.

Other forms of the second embodiment of the present invention relate to an optical article having an antireflection layer formed directly on an optical substrate or with at least one other layer interposed between the optical substrate and the antireflection layer, and an antifouling layer. layer. The antireflection layer includes a first low-refractive index sublayer and a second low-refractive-index sublayer, the surface of the first low-refractive index sublayer facing away from the optical substrate is subjected to nitriding treatment, and on the back of the first low-refractive index sublayer Forming the 2nd low refractive index sublayer on the surface of the optical substrate, and at least one high refractive index sublayer is sandwiched between the 1st low refractive index sublayer and the 2nd low refractive index sublayer, and then in the 2nd low refractive index sublayer The antifouling layer is directly laminated on the surface of the sublayer facing away from the optical substrate.

In addition, the optical article in another aspect of the second embodiment of the present invention has an antireflection layer formed directly on the optical substrate or an antireflection layer interposed between the optical substrate and the antireflection layer, and an antifouling layer. at least one other layer. The antireflection layer includes a first low-refractive index sublayer and a second low-refractive-index sublayer, the first low-refractive index sublayer has a nitrogen-containing partial layer on the side facing away from the optical substrate, and in the first low-refractive index sublayer The second low-refractive-index sublayer is formed on the surface facing away from the optical substrate, and at least one high-refractive-index sublayer is sandwiched between the first low-refractive-index sublayer and the second low-refractive-index sublayer. The antifouling layer is directly laminated on the surface of the refractive index sublayer facing away from the optical substrate. The partial layers here are the same as those described in the first embodiment.

That is, the above-mentioned optical article has an anti-reflection layer formed directly on the optical substrate or an anti-reflection layer interposed between the optical substrate and the anti-reflection layer, and an anti-fouling layer formed directly on the anti-reflection layer. Layer other layers, the anti-reflection layer includes more than two sub-layers, and among the more than two sub-layers, except for the outermost layer of the anti-reflection layer, at least one layer is a surface layer that has undergone nitriding treatment, that is The surface nitrided layer is a layer mainly composed of _SiOx and is a layer including a nitrided portion of the surface of the layer facing away from the optical substrate. One form of the anti-reflection layer is to include two or more low-refractive index sub-layers, one of these two or more low-refractive-index sub-layers is the outermost layer, and the other of these two or more low-refractive index sub-layers At least one layer in the layer is a surface layer with nitriding treatment, and the outermost low-refractive index sub-layer is formed on the surface of the other low-refractive-index sub-layers facing away from the optical substrate, and on the other low-refractive index sub-layers At least one high-refractive-index sub-layer is sandwiched between the layer and the outermost low-refractive-index sub-layer.

Through the nitriding treatment of the first low refractive index sub-layer, at least one sub-layer forms a nitrogen-containing partial layer on the side facing away from the optical substrate, and since the surface that is easily scratched is nitrided, the surface resistance can be improved. Abrasion. In addition, since the second low-refractive index sublayer on which the anti-fouling layer is laminated is not nitrided, the adhesion between the second low-refractive index sub-layer and the anti-fouling layer can be maintained, thereby improving the durability of the anti-fouling layer. durability.

Preferably, the first and second low-refractive index sublayers are formed of silicon dioxide. In this case, the partial layer contains Si _s O _{t Nu} (s and u are positive integers, and t is an integer of 0 or greater). When the sublayer formed of silicon dioxide is nitridated, a silicon nitride-containing region is partially or entirely formed on the surface of the sublayer, whereby scratch resistance can be improved. In addition, since the thickness and/or area of the partial layer formed by the nitriding treatment is limited, the optical properties of silicon dioxide as a sublayer are maintained. Therefore, there is little need to change the film design of the anti-reflection layer. In addition, silicon nitride can improve scratch resistance, and at the same time can effectively utilize the characteristics of the sublayer formed of silicon dioxide, that is, impart adhesion between the substrate and the upper layer. In addition, since the silicon oxide in the uppermost layer on which the antifouling layer is laminated is not nitrided, scratch resistance can be improved while maintaining the durability of the antifouling layer.

Compositions suitable for forming the antifouling layer are fluorine-containing silane compounds. An example of the fluorine-containing silane compound suitable for the antifouling layer is a compound represented by the following general formula (1).

Compound 1

In the general formula (1), Rf ¹ represents a perfluoroalkyl group, X represents a hydrogen atom, a bromine atom or an iodine atom, Y represents a hydrogen atom or a lower alkyl group, Z represents a fluorine atom or a trifluoromethyl group, and R ¹ represents a hydroxyl group Or a hydrolyzable group, R ² represents a hydrogen atom or a monovalent hydrocarbon group. a, b, c, d and e are integers of 0 or more than 1, and a+b+c+d+e is at least 1 or more, for each repetition enclosed by a, b, c, d and e in the general formula The order in which the cells exist is not limited. f represents 0, 1 or 2, g represents 1, 2 or 3, and h represents an integer of 1 or more.

Another example of the fluorine-containing silane compound suitable for the antifouling layer is a compound represented by the following general formula (2).

Compound 2

In the general formula (2), Rf ² includes units represented by the formula: —(C _k F _2k )O—(where k is an integer of 1 to 6), and represents a linear perfluoropolyalkylene having no branch Divalent group of base ether structure. R ³ represents a monovalent hydrocarbon group having 1 to 8 carbon atoms, and X represents a hydrolyzable group or a halogen atom. P represents 0, 1 or 2, n represents an integer of 1 to 5, and m and r represent 2 or 3.

4 is a schematic diagram showing the structure of a film forming apparatus 50 for forming a multi-layered antireflection layer on the surface of a substrate (work) 40 placed on a supporting device 80 by vacuum evaporation.

The film forming apparatus 50 shown in FIG. 4 is different from the film forming apparatus 50 shown in FIG. 1 in the function of the chamber CH3. In the film forming apparatus 50 shown in FIG. 4 , the chamber CH3 has a function of forming an antifouling layer by vapor-depositing a fluorine-containing silane compound in the chamber in addition to the function as an outlet chamber. Therefore, an antifouling layer vapor deposition source 59a impregnated with a fluorine-containing silane compound, a heater (halogen lamp) 68, and a compensation plate 67 for controlling the discharge amount of the fluorine-containing silane compound by adjusting the opening degree are provided inside the chamber CH3. . Chamber CH3 is maintained at a suitable pressure by a vacuum generator 54 equipped with a rotary pump 54a, a Roots pump 54b and a turbomolecular pump 54c. The workpiece substrate 40 taken out from the chamber CH3 together with the supporting device 80 is placed in a constant temperature and humidity chamber (not shown in the figure), and the workpiece substrate 40 is annealed in an atmosphere of appropriate humidity and temperature. Furthermore, the workpiece substrate 40 is aged by leaving it in a room for a predetermined time. The other structures and functions are the same as those of the film-forming apparatus 50 of the first embodiment, and therefore are denoted by the same symbols in the drawings, and their repeated descriptions are omitted.

FIG. 5 is a flowchart showing a process of forming an antireflection layer having a multilayer structure on the workpiece substrate 40 in the film forming apparatus 50 . In addition, FIG. 6 is a cross-sectional view showing a film structure of an optical article 10 b of the present embodiment including the antireflection layer 3 and the antifouling layer 4 . As an example of the anti-reflection layer 3, it includes a first sublayer 31 formed on a base material formed of silicon oxide, a second sublayer 32 formed of zirconium oxide, a third sublayer 33 formed of silicon oxide, and The fourth sublayer 34 is composed of zirconia, and the fifth sublayer 35 is composed of silicon oxide.

When the optical substrate (substrate) 1 is made of plastic, in step 101, the hard coat layer 2 is formed on the optical substrate 1 before the anti-reflection layer 3 is formed, in the same manner as the manufacturing method shown in FIG. 2 .

The substrate 1 on which the hard-coat layer 2 was formed is fixed on the support device 80 as a workpiece substrate 40 and transported to the film forming device 50 . In the film forming apparatus 50 , firstly, the support device 80 is introduced into the chamber CH1 for degassing, and then the support device 80 is moved into the chamber CH2 to perform the plasma treatment in step 102 . In step 103, the first sublayer 31 made of silicon oxide is formed (layer formation step (first step)), and then, in step 104, the surface of the sublayer 31 is nitrided by plasma treatment or ion gun treatment. (Nitriding process). In this way, the nitride-containing partial layer 39 is formed on the surface (the surface facing away from the substrate 1 ) of the sublayer 31 made of silicon oxide, covering the whole or part of the surface. At this time, a gas of any composition containing nitrogen can be used as the introduction gas, for example, 100% nitrogen, a mixed gas of nitrogen and oxygen, a mixed gas of nitrogen and argon, or a mixed gas of nitrogen, oxygen and argon Wait for gas.

After forming the second sublayer 32 made of zirconia in step 105, the third sublayer 33 made of silicon oxide is formed in step 106 (layer forming step (first step)), and then in step 107, The same surface nitriding (nitriding process) as in step 104 is performed.

After forming the fourth sublayer 34 made of zirconia in step 108, the fifth sublayer 35 made of silicon oxide is formed in step 109 (layer forming step (second step)). The fifth sublayer 35 is the uppermost layer of the antireflection layer 3 . Therefore, after the layer formation step (second step), in step 110, the support device 80 is moved to the chamber CH3, and the anti-corrosion layer made of a fluorine-containing silane compound is directly formed on the fifth sublayer 35 made of silicon oxide. Dirty layer 4. In this way, the antireflection layer 3 and the antifouling layer 4 having a five-layer structure were formed on one side of the optical article. In step 111 , the substrate 40 is turned over and fixed on the supporting device 80 , and steps 102 to 110 are repeated. When the antireflection layer 3 and the antifouling layer 4 are formed on both sides of the substrate 40 , the substrate 40 is taken out at step 112 .

Here, there are three silicon oxide sub-layers 31 , 33 and 35 . Except that the uppermost sub-layer 35 can be nitrided, one or both of the low-refractive index sub-layers 31 and 33 can also be nitrided. When the uppermost sublayer 35 is the second low-refractive index sublayer, it is not subjected to nitriding treatment. In addition, since only the extremely thin surface of the silicon oxide sublayer is nitrided in the above-mentioned nitriding treatment, the performance as the antireflection layer 3 is hardly affected.

(Embodiment 2-1)

Hereinafter, according to the manufacturing method shown in FIG. 5 , several examples of manufacturing plastic spectacle lenses as optical articles will be described. In each of the following Examples and Comparative Examples, a plastic lens substrate for eyeglasses (manufactured by Seiko Epson Co., trade name: Seiko Supper Sovereign) was used as the optical substrate 1 . In step 101 , a hard coat layer 2 is formed on both sides of an optical substrate 1 . The optical substrate 1 on which the hard coat layer 2 is formed is used as a workpiece substrate 40, and the antireflection layer 3 is formed thereon.

The workpiece substrate 40 is fixed on the dome cover 81 of the supporting device 80 with the concave surface facing down, and then transported to the film forming device 50 . In step 102, after the chamber CH1 is degassed, 100% argon gas is introduced into the chamber CH2, and while the gas pressure is controlled at 4.0×10 ^-2 Pa, the plasma generated by the high-frequency plasma generator is used to treat the workpiece. Substrate 40 is processed. Plasma treatment was performed for 1 minute under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 400 W. The purpose of this treatment is to clean the surface of the substrate, so that the adhesion between the substrate 1 and the antireflection layer 3 is improved.

Steps 103 to 110 are then carried out to alternately vapor-deposit SiO ₂ sublayers 31 , 33 and 35 and ZrO ₂ sublayers 32 and 34 , thereby forming the antireflection layer 3 composed of these sublayers. The film thickness of each layer was adjusted so that the film thickness of the first sublayer (SiO ₂ ) 31 was 0.09λ, the film thickness of the second sublayer (ZrO ₂ ) 32 was 0.16λ, and the film thickness of the third sublayer (SiO ₂ ) 33 The thickness of the film is 0.05λ, the thickness of the fourth sublayer (ZrO ₂ ) 34 is 0.27λ, and the thickness of the fifth sublayer (SiO ₂ ) 35 is 0.27λ.

The uppermost layer 35 of the antireflection layer 3 is a SiO ₂ layer. The plasma generator 60 is used in the nitriding treatment in steps 104 and 107 . Therefore, after evaporating the _SiO2 layer, nitrogen and oxygen are introduced into the chamber CH2 at a ratio of 7:3, and while the gas pressure is controlled at 4.0× ^10-2 Pa, a high-frequency plasma generator is used to generate plasma . Plasma treatment was performed for 5 minutes under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 600 W. In this way, the nitride-containing partial layer 39 is formed on the SiO ₂ layer surface of the first sublayer 31 and the third sublayer 33 . That is, the first sublayer 31 and the third sublayer 33 are sublayers (surface nitriding layers) including nitriding portions.

Then, the support device 80 is moved to the chamber CH3, and the antifouling layer 4 is formed (step 110). A fluorine-containing organosilicon compound manufactured by Shin-Etsu Chemical Co., Ltd. (trade name: KY-130, a compound represented by the above general formula (2)) was used as the vapor deposition source 59a. This KY-130 was diluted with a fluorine-based solvent (manufactured by Sumitomo 3M, Ltd., trade name: Novec HFE-7200) to prepare a solution with a solid content concentration of 3%, and 1 g of this solution was impregnated into porous ceramic pellets (pellets) The particles are dried, and the dried particles are fixed in the chamber CH3 as the vapor deposition source 59a. In the film formation process, a halogen lamp was used as the heater 68 to heat the particles as the vapor deposition source 59a to 600° C. to vapor-deposit the fluorine-containing organosilicon compound. The vapor deposition time was 3 minutes.

After the antifouling layer 4 is formed, take out the supporting device 80 from the chamber, turn the lens convex side down and fix it on the arched cover 81 of the supporting device 80, and then carry out the same treatment as above. In this way, a plastic lens (sample S2-1) having an antireflection layer 3 and an antifouling layer 4 on both sides of a workpiece substrate 40 (lens base material 1), that is, on the base material 1 formed with a hard coat layer 2, was manufactured. The other side also has an antireflective layer 3 and an antifouling layer 4 . In sample S2-1, the silicon dioxide sub-layers 31 and 33 of the anti-reflection layer 3 are used as the first low-refractive-index sub-layer, and their surfaces are nitrided, that is, the surface facing away from the substrate 1 is nitrided. In addition, the sub-layer 35 serves as the second low-refractive-index sub-layer on which the antifouling layer 4 is directly formed.

(Embodiment 2-2)

In Example 2-2, step 107 was not performed, and the others were the same as in Example 2-1, and a plastic lens (sample S2-2) having an anti-reflection layer 3 with a 5-layer structure was manufactured. Therefore, in the sample S2-2 of this Example 2-2, among the silicon dioxide sublayers 31, 33, and 35 included in the antireflection layer 3, only the innermost layer (1st sublayer) 31 (that is, The sublayer 31) of the antireflection layer 3 forming the surface of the optical substrate 1 is subjected to nitriding treatment to form a nitride-containing partial layer 39 .

(Embodiment 2-3)

In Example 2-3, step 104 was not performed, and the others were the same as in Example 2-1, and a plastic lens (sample S2-3) having a five-layer antireflection layer 3 was manufactured. Therefore, in the sample S2-3 of Example 2-3, among the silicon dioxide sublayers 31, 33, and 35 included in the antireflective layer 3, only the third sublayer 33 was subjected to nitriding treatment, forming Nitride partial layer 39 .

(Embodiment 2-4)

In Embodiment 2-4, steps 102 to 110 are carried out to perform nitriding treatment on the silicon dioxide sub-layers 31 and 33 included in the anti-reflection layer 3 . However, for the nitriding treatment in steps 104 and 107, the ion gun 70 is used instead of the plasma generating device 60. Therefore, the nitrogen gas 64 a and the oxygen gas 63 are introduced into the ion gun 70 at a ratio of 7:3, and the flow rate is controlled to be 35 SCCM to irradiate the sub-layers 31 and 33 with ions. Ion irradiation was performed for 5 minutes under ion irradiation conditions of frequency 13.56MHz, RF power 450W, accelerating voltage 500V, and suppressing voltage 300V while maintaining the chamber pressure at the time of treatment at 4×10 ^-3 Pa. Others are the same as in Example 2-1.

Therefore, in the sample S2-4 of the embodiment 2-4, the silicon dioxide sub-layers 31 and 33 of the anti-reflection layer 3 are used as the first low-refractive-index sub-layer, and the surface thereof is subjected to nitriding treatment, that is, the surface faces away from the substrate 1. The surface of the substrate is nitrided to form a nitride-containing partial layer 39 . In addition, the sub-layer 35 serves as the second low-refractive-index sub-layer on which the antifouling layer 4 is directly formed.

(Embodiment 2-5)

In Example 2-5, the same steps 102 to 110 as in Example 2-1 were carried out to nitride the silicon dioxide sublayers 31 and 33 included in the antireflection layer 3 . However, in step 110, a fluorine-containing organosilicon compound manufactured by Daikin Industries, Ltd. (trade name: OPTOOL DSX, a compound represented by the above general formula (1)) is used as the vapor deposition layer for forming the antifouling layer 4. Source 59a. Therefore, the OPTOOL DSX was diluted with a fluorine-based solvent (manufactured by Daikin Industries, Ltd., trade name: DEMNAM SOLVENT) to prepare a solution with a solid content concentration of 3%, and 1 g of the solution was impregnated into porous ceramic pellets (pellets) and The particles are dried, and the dried particles are fixed in the chamber CH3 as a vapor deposition source 59a.

Therefore, in the sample S2-5 of the embodiment 2-5, the silicon dioxide sub-layers 31 and 33 of the anti-reflection layer 3 are used as the first low-refractive-index sub-layer, and the surface thereof is subjected to nitriding treatment, that is, the surface faces away from the substrate 1. The surface of the substrate is nitrided to form a nitride-containing partial layer 39 . In addition, the sub-layer 35 serves as the second low-refractive-index sub-layer on which the antifouling layer 4 is directly formed.

(Embodiment 2-6)

In Examples 2-6, lenses having an antireflection layer of a 7-layer structure were produced. Therefore, the process of nitriding the 5th silicon dioxide sublayer, the process of evaporating the 6th sublayer, and the process of evaporating the 7th silicon dioxide sublayer as the outermost layer are added. In step 110, the 7th silicon dioxide sublayer is The antifouling layer 4 is formed on the surface of the silicon sublayer. In addition, TiO ₂ is used instead of ZrO ₂ when forming the high refractive index sublayer. Others are the same as in Example 2-1. In the process of forming these high-refractive-index sublayers, TiO ₂ is vapor-deposited by ion accelerator vapor deposition. Regarding the irradiation conditions at this time, 100% oxygen with a controlled flow rate of 35 SCCM was introduced into the ion gun 70, the frequency was adjusted to 13.56 MHz, the RF power was 450 W, the acceleration voltage was 500 V, and the suppression voltage was 300 V. The pressure in the chamber during the treatment was 4×10 ^-3 Pa. In this case, the thickness of the first sublayer (SiO ₂ ) is 0.08λ, the thickness of the second sublayer (TiO ₂ ) is 0.07λ, the thickness of the third sublayer (SiO ₂ ) is 0.10λ, and the thickness of the fourth The thickness of the sublayer (TiO ₂ ) is 0.18λ, the thickness of the fifth sublayer (SiO ₂ ) is 0.07λ, the thickness of the sixth sublayer (TiO ₂ ) is 0.14λ, and the thickness of the seventh sublayer (SiO ₂ ) has a film thickness of 0.26λ.

Therefore, in the sample S2-6 of this embodiment 2-6, all the silicon dioxide sublayers included in the antireflection layer 3 except the outermost silicon dioxide sublayer are subjected to nitriding treatment to form nitride-containing Partial layer 39.

(Embodiment 2-7)

In Embodiment 2-7, steps 104 and 107 of nitriding the layers 31 and 33 corresponding to the first low-refractive index sublayer are omitted, but the layer 35 corresponding to the second low-refractive index sub-layer is Carry out nitriding, then form the antifouling layer 4, by this manufacturing method, have the same composition as embodiment 2-1, namely have the plastic lens of antireflection layer 3 and antifouling layer 4 (sample S2-7) , the anti-reflection layer has a 5-layer structure consisting of a low refractive index sublayer of _SiO2 and a high refractive index sublayer of _ZrO2 . Others are the same as in Example 2-1.

(Embodiment 2-8)

In Examples 2-8, a plastic lens (sample S2-8) was fabricated with the same composition as in Example 2-6, i.e., with a low-refractive-index sublayer of _SiO2 and a high-refractive-index sublayer of _TiO2 The antireflection layer 3 of the 7-layer structure is formed, and only the uppermost sublayer of the antireflection layer 3 corresponding to the second low refractive index sublayer is subjected to nitriding treatment, and the uppermost sublayer of the nitriding treatment is An antifouling layer 4 is formed on it. Other is identical with embodiment 2-6.

(Comparative example 2-1)

In Comparative Example 2-1, steps 104 and 107 were not performed, and a plastic lens (sample SR2-1) with the same composition as in Example 2-1 was manufactured, that is, it had a low-refractive-index sublayer made of _SiO and ZrO The anti-reflection layer 3 and the anti-fouling layer 4 of the five-layer structure composed of high refractive index sub-layers _{of 2} , and no nitriding treatment was performed. Others are the same as in Example 2-1. Therefore, in the sample SR2-1 of the comparative example 2-1, all of the silicon dioxide sublayers 31, 33, and 35 included in the antireflection layer 3 were not subjected to nitriding treatment.

(comparative example 2-2)

In Comparative Example 2-2, a plastic lens (sample SR2-2) having the same composition as in Example 2-6 was produced, that is, it had a low-refractive-index sublayer of _SiO2 and a high-refractive-index sublayer of _TiO2 The anti-reflective layer 3 of the 7-layer structure is formed, and no nitriding treatment is performed. Other is identical with embodiment 2-6. Therefore, in the sample SR2-2 of Comparative Example 2-2, the nitriding treatment was not performed on all the silicon dioxide sublayers included in the antireflection layer 3 .

(evaluate)

Scratch resistance and antifouling layer of samples S2-1 to S2-8, SR2-1 to SR2-2 manufactured in Examples 2-1 to 2-8 and Comparative Examples 2-1 to 2-2 using the following methods 4 durability was evaluated. The evaluation results are summarized in Table 2(a) and Table 2(b).

In order to evaluate the scratch resistance, steel wool (#0000) wrapped around a jig was loaded with a load of 2 kg. Reciprocate 50 times on the outer surface. The degree of scratch thus produced was compared with the standard sample, and the scratch resistance was evaluated in four grades of A, B, C and D. Among them, A represents the best, and B, C, and D represent the deterioration in sequence.

In order to evaluate the durability of the antifouling layer 4, a cotton cloth with a load of 200 g was passed back and forth 5000 times on the convex surface of the lens to perform accelerated treatment. The antifouling performance before and after this accelerated treatment was evaluated by the contact angle and the wiping property of the oily ink. For the measurement of the contact angle, the contact angle of pure water was measured by the drop method using a contact angle meter (manufactured by Kyowa Science Co., Ltd., model "CA-D Type"). For the wipe-off property of the oil-based ink, a straight line of about 4 cm was drawn on the convex surface of the lens with a black oil-based marker pen (manufactured by Zebra Co., Ltd., trade name: High Mackee Care) and left for 5 minutes. Then, the marked portion was wiped with wiping paper (manufactured by Nippon Paper Crecia Co., Ltd., trade name: K-Dry), and the wiping property of the oil-based ink was judged according to the following criteria.

◯: Completely removed by wiping 10 times or less.

△: Completely removed by wiping 11 to 20 times.

×: Unremoved parts remained after wiping off 20 times.

Table 2(a) and Table 2(b) below are a summary of evaluation results of lenses obtained in Examples and Comparative Examples in the second embodiment.

Table 2(a)

Table 2(b)

In samples S2-1 to S2-8 of Examples 2-1 to 2-8, at least one silicon dioxide sublayer was subjected to nitriding treatment, and the scratch resistance test of these samples was evaluated as good (A) or pass (B). On the other hand, the evaluation of the scratch resistance test of samples SR2-1 and SR2-2 of Comparative Example 2-1 and Comparative Example 2-2 not subjected to nitriding treatment was poor (D). The results show that scratch resistance can be improved by nitriding at least one silicon dioxide sublayer. In addition, compared with the samples of Examples in which all silicon dioxide sublayers except the outermost layer were nitrided, the samples of Examples 2-2 and 2-3 in which only one silicon dioxide sublayer was nitrided The evaluation of the level of scratch resistance was lower at B, but the level was within a completely allowable range.

With regard to the durability of the antifouling layer, samples S2-1 to S2-6 of Examples 2-1 to 2-6 that were not subjected to nitriding treatment on the uppermost low-refractive index sublayer of the antireflective layer 3, and Comparative Example 2- The samples SR2-1 and SR2-2 of 1 and 2-2 had no change in wiping performance before and after accelerated treatment, and had sufficient durability. On the other hand, in samples S2-7 and S2-8 of Examples 2-7 and 2-8 in which the uppermost low-refractive index sublayer of the antireflection layer 3 was nitrided, the wiping performance before the accelerated treatment was sufficient. , and the wiping performance after accelerated treatment is reduced. It can be seen from this that the durability of the anti-fouling layer 4 can be greatly improved by not performing nitriding treatment on the uppermost low-refractive index sub-layer 35 of the anti-reflection layer 3 .

When comprehensively evaluated, all samples S2-1 to S2-8 of Examples were ⊚ (excellent) or ◯ (good) as products. All samples SR2-1 to SR2-2 of the comparative example were x (failure). The results show that scratch resistance can be improved by nitriding at least one silicon dioxide sublayer. In addition, it can be seen that the wiping performance can also be improved by not nitriding the uppermost low-refractive index sublayer of the anti-reflection layer 3 .

In addition, the above-mentioned second embodiment (example) relates to an optical article having an antireflection layer and an antifouling layer formed on a plastic spectacle lens having a hard coat layer, but for an optical article having a glass substrate, it may be The antireflective layer is formed on the substrate without a hard coat layer interposed between the substrate and the antireflective layer. In addition, the optical article is not limited to spectacle lenses, but includes optical elements such as optical elements of image display devices, prisms, optical fibers, elements for information recording media, and optical filters, and the above-described embodiments can also be applied to these optical articles. The disclosed manufacturing method.

(third embodiment)

One of the inventions described in the third embodiment of the present invention (the first invention) relates to a method of manufacturing an optical article having one or more thin films on an optical substrate, and the first invention is characterized in that, in the thin film, The outermost film is a low-refractive-index film, and the surface of the low-refractive-index film is subjected to nitriding treatment.

According to the above-mentioned first invention, by nitriding the surface of the outermost low-refractive-index thin film formed on the optical substrate, the durability of the thin film, especially the scratch resistance can be improved.

Invention 2 (the second invention) described in the third embodiment of the present invention is characterized in that, in the above-mentioned first invention, the nitriding treatment is performed after forming the low-refractive-index thin film by vacuum deposition, so that In the nitriding treatment, a gas containing nitrogen is introduced into the vacuum chamber where the vacuum evaporation is performed, and plasma treatment or ion gun treatment is performed.

According to the above-mentioned second invention, after the low-refractive-index film is formed on the optical substrate, the gas containing nitrogen gas is introduced into the vacuum chamber, and the surface of the low-refractive-index film can be nitrided by plasma treatment or ion gun treatment. The durability, especially the scratch resistance, of the film is thereby improved.

The third invention (the third invention) described in the third embodiment of the present invention is characterized in that, in the above-mentioned first invention or the above-mentioned second invention, the low-refractive-index thin film containing silicon dioxide as a main component is formed.

According to the above-mentioned third invention, by nitriding the low-refractive-index thin film mainly composed of silicon dioxide, the durability of the optical article, especially the scratch resistance can be improved.

The fourth invention (the fourth invention) described in the third embodiment of the present invention relates to an optical article having one or more thin films on an optical substrate, and the fourth invention is characterized in that the outermost layer is formed in the thin film The film is a low-refractive-index film having a nitrogen-containing partial layer on the surface facing away from the optical substrate. The partial layer mentioned here in this application refers to the surface layer part of the low refractive index film. The present invention relates to nitriding treatment of the surface portion.

According to the above-mentioned fourth invention, since the nitrogen-containing partial layer is formed on the surface of the outermost low-refractive index film, the durability of the optical article, especially the scratch resistance can be improved.

The fifth invention (fifth invention) described in the third embodiment of the present invention is characterized in that, in the above-mentioned fourth invention, the low-refractive-index thin film containing silicon dioxide as a main component is formed.

According to the above-mentioned fifth invention, the durability, especially the scratch resistance, of the optical article can be improved by nitriding the thin film mainly composed of silicon dioxide.

In the third embodiment, since the low-refractive index film made of silicon dioxide or the like is nitrided, that is, the surface of the low-refractive index film is all or partially nitrided to form a nitrogen-containing partial layer, it is possible to improve Scratch resistance for surfaces prone to marring. In this case, the partial layer contains Si _s O _{t Nu} (s and u are positive integers, and t is an integer of 0 or greater).

In addition, in the above-mentioned production method, a gas containing nitrogen gas is introduced into a vacuum chamber, and plasma treatment or ion gun treatment is performed, whereby the surface of a low-refractive index film such as silicon dioxide can be partially or completely nitrided. Therefore, precise film thickness control is not required for introducing the nitrided layer, and the nitrided film can be easily introduced without controlling the ion current or precisely timing, thereby improving the scratch resistance of the antireflection layer. In particular, in the plasma treatment, silicon nitride can be easily introduced into an apparatus for vacuum evaporation or during the evaporation process without using an ion source.

The aforementioned low-refractive-index film made of silicon dioxide or the like can form a part of various functional films, for example, a part of an antireflection film. For the low refractive index film made of silicon dioxide, since there is a mixture of _SiO and Si _s O _t Nu (s, _u are positive integers, and t is an integer greater than 0) in the formed part of the layer, therefore, The refractive index of some layers is in the range of 1.45 to 2.05, but since the thickness and/or area are limited, the influence of the film design of the anti-reflection film is minimal.

In addition, an antifouling film can be formed on the uppermost layer of the functional film. In this case, it is preferable to further form a low-refractive-index film on the nitrogen-containing partial layer of the low-refractive-index film. In this way, by not nitriding the silicon oxide of the uppermost layer on which the antifouling layer is laminated, the durability of the antifouling layer can be maintained and the scratch resistance can be improved.

A substance suitable for forming the composition of the antifouling layer is a fluorine-containing silane compound, and an example of the fluorine-containing silane compound suitable for the antifouling layer is a compound represented by the above-mentioned general formula (1).

Another example of the fluorine-containing silane compound suitable for the antifouling layer is a compound represented by the above-mentioned general formula (2).

7 shows a schematic structural view of a film forming apparatus 50 for forming various functional thin films formed on the surface of a substrate (work) 40 placed on a supporting apparatus 80 by vacuum evaporation. The support device 80 is the same as that shown in FIG. 1 . The film forming apparatus 50 has three chambers CH1, CH2, and CH3 through which the supporting device 80 can pass. The chambers CH1 to CH3 can be mutually sealed. Also, the internal pressures of the chambers CH1 to CH3 are controlled by vacuum generators 52 , 53 and 54 , respectively. Chamber CH1 is the entrance or door chamber. Chamber CH2 is the second chamber for forming various functional thin films. In addition, a mass flow controller 66 for controlling the indoor atmosphere is connected to the chamber CH2. Oxygen supply source 63, argon supply source 64b and nitrogen supply source (not shown among the figure) are connected with mass flow controller 66, can control the atmospheric gas in the chamber CH2 as 100% oxygen, 100% argon or 100% like this Nitrogen, or a mixture of these gases in appropriate proportions.

The chamber CH3 is a chamber for forming an antifouling layer by vapor-depositing a fluorine-containing silane compound. Therefore, inside the chamber CH3 there are an antifouling layer vapor deposition source 59b impregnated with a fluorine-containing silane compound, a heater (halogen lamp) 68, and a compensation plate 67 for controlling the discharge amount of the fluorine-containing silane compound by adjusting the opening. Chamber CH3 is maintained at an appropriate pressure by a vacuum generator 54 equipped with a rotary pump 54a, a Roots pump 54b and a turbomolecular pump 54c. In the case of forming the anti-fouling layer, the workpiece substrate 40 taken out together with the supporting device 80 from the chamber CH3 is put into a constant temperature and humidity tank (not shown), and it is placed in an atmosphere of appropriate humidity and temperature. annealing. Furthermore, the workpiece substrate 40 is aged by leaving it in a room for a predetermined period of time. For the case where the antifouling layer is not formed in the chamber CH3, the above-mentioned annealing and aging are not necessary. The other structures and functions are the same as those of the film forming apparatus 50 of the first embodiment, and therefore, are denoted by the same symbols in the drawings, and their repeated descriptions are omitted.

FIG. 8 shows a flow chart of the process of forming a single-layer low-refractive index film in the film forming device 50 , taking the process of forming a functional film on the workpiece substrate 40 as an example. In addition, FIG. 9 is a cross-sectional view showing a film structure of an optical article 10c according to this embodiment.

When the optical substrate (base material) 1 is plastic, in step 151 , before forming the low-refractive index film 30 , a hard coat layer 2 is first formed on the optical substrate 1 . The formation of this hard-coat layer 2 is the same as that of the above-mentioned embodiment.

The substrate 1 on which the hard-coat layer 2 was formed is fixed on the support device 80 as a workpiece substrate 40 and transported to the film forming device 50 . In the film forming apparatus 50 , first, the support device 80 is introduced into the chamber CH1 and degassed, and then the support device 80 is moved into the chamber CH2 to perform plasma treatment in step 152 . The purpose of this treatment is to clean the surface, thereby improving the adhesion between the hard coat layer 2 on the substrate 1 and the low-refractive index film 30 .

In step 153, after forming a silicon dioxide film as a low-refractive index film, in step 154, use plasma treatment or ion gun treatment to nitride the surface, so that on the surface of the silicon dioxide film 30 (facing away from the substrate 1 The nitride-containing partial layer 39 covering all or part of the surface is formed on the surface thereof. That is, the silicon dioxide thin film 30 is a layer including a nitrided portion (surface nitrided layer). At this time, a gas of any composition containing nitrogen is used as the introduction gas, for example, 100% nitrogen, a mixed gas of nitrogen and oxygen, a mixed gas of nitrogen and argon, or a mixed gas of nitrogen, oxygen and argon, etc. gas.

Thus, a functional thin film is formed on one side of the optical article. Therefore, in step 155, the substrate 40 is turned over and fixed on the supporting device 80, and steps 152-154 are repeated. When the functional thin film is formed on both sides of the substrate 40 , the substrate 40 is taken out at step 156 .

(Embodiment 3-1)

Hereinafter, according to the manufacturing method shown in FIG. 8 , several examples of manufacturing plastic spectacle lenses as optical articles will be described. In each of the following Examples and Comparative Examples, a plastic lens substrate for eyeglasses (manufactured by Seiko Epson Co., trade name: Seiko Supper Sovereign) was used as the optical substrate 1 . In step 151, a work substrate 40 having hard coat layers 2 formed on both surfaces of the substrate 1 is used, and a silicon dioxide thin film 30 as a low refractive index thin film is formed thereon.

The workpiece substrate 40 is fixed on the dome cover 81 of the supporting device 80 with the concave surface facing down, and then transported to the film forming device 50 . After degassing in chamber CH1, proceed to step 152 in chamber CH2, introducing 100% argon gas, while controlling the gas pressure to 4.0×10 ^-2 Pa, using plasma generated by a high-frequency plasma generator to treat the workpiece substrate 40 for processing. Plasma treatment was performed for 1 minute under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 400 W. The purpose of this treatment is to clean the surface of the substrate to improve the adhesion between the substrate 1 and the low-refractive index film 30 .

Next, step 153 is performed to vapor-deposit the silicon dioxide thin film 30. The silicon dioxide thin film 30 has a film thickness of 90 nm, and this film thickness shows good performance as a hard film and an antireflection film.

In the nitriding treatment in step 154, the plasma generator 60 is used. Therefore, after evaporating the silicon dioxide film, nitrogen and oxygen are introduced into the chamber CH2 at a ratio of 7:3. While controlling the gas pressure to 4.0×10 ^-2 Pa, a high-frequency plasma generator is used to Plasma is generated. Plasma treatment was performed for 5 minutes under the conditions of plasma generation at a frequency of 13.56 MHz and a power of 600 W. Thus, the nitride-containing partial layer 39 is formed on the surface of the silicon dioxide film 30 .

Then, the support device 80 moved to the chamber CH3 is taken out from the chamber, and the inverted lens is fixed on the arched cover 81 of the support device 80 with the convex surface downward, and then the same process as above is carried out. (Sample S3-1)

(Embodiment 3-2)

In Example 3-2, after the nitriding treatment in Example 3-1, the silicon dioxide thin film was vapor-deposited again. This is effective for forming an antifouling layer on the nitrided silicon dioxide film 30 which is the base layer (preparation layer) of the antifouling layer. The antifouling layer exhibits good durability as long as the film thickness of the silicon dioxide thin film (base layer) formed after the nitriding treatment is at least (at least) 5 nm.

Then, the support device 80 is moved into the chamber CH3, and the antifouling layer 4 is formed. A fluorine-containing organosilicon compound manufactured by Shin-Etsu Chemical Co., Ltd. (trade name: KY-130, a compound represented by the above general formula (2)) was used as the vapor deposition source 59b. This KY-130 was diluted with a fluorine-based solvent (manufactured by Sumitomo 3M, Ltd., trade name: Novec HFE-7200) to prepare a solution with a solid content concentration of 3%, and 1 g of this solution was impregnated into porous ceramic pellets (pellets) The particles are dried, and the dried particles are fixed in the chamber CH3 as the vapor deposition source 59b. In the film forming process, a halogen lamp was used as the heater 68 to heat the particles as the vapor deposition source 59b to 600° C. to vapor-deposit the fluorine-containing organosilicon compound. The vapor deposition time was 3 minutes.

Then, the support device 80 in the chamber CH3 is taken out from the chamber, and the inverted lens is fixed on the arched cover 81 of the support device 80 with the convex surface downward, and the same process as above is performed again. (Sample S3-2)

(Comparative example 3-1)

In Comparative Example 3-1, a plastic lens (sample SR3-1) not subjected to the nitriding treatment in Example 3-1 was manufactured.

(Comparative example 3-2)

In Comparative Example 3-2, a plastic lens (sample SR3-2) not subjected to the nitriding treatment in Example 3-2 was manufactured.

(evaluate)

The scratch resistance of samples S3-1, S3-2, SR3-1 and SR3-2 produced in Examples 3-1 and 3-2 and Comparative Examples 3-1 and 3-2 were evaluated by the following method. The evaluation results are summarized in Table 3.

In order to evaluate the scratch resistance, the steel wool (#0000) wrapped on the jig was reciprocated 50 times on the outermost surface of each sample S3-1, S3-2, SR3-1 and SR3-2 under a load of 2 kg. . The degree of scratch thus produced was compared with the standard sample, and the scratch resistance was evaluated in four grades of A, B, C and D. Among them, A represents the best, and B, C, and D represent the deterioration in sequence.

table 3

In the samples S3-1 and S3-2 of Examples 3-1 and 3-2, the silicon dioxide film was nitrided, therefore, the evaluation of the scratch resistance test of the samples S3-1 and S3-2 was Good (A). On the other hand, the evaluation of the scratch resistance test of the samples SR3-1 and SR3-2 of Comparative Example 3-1 and Comparative Example 3-2 which were not subjected to nitriding treatment was unacceptable (D). As a result, it was found that the scratch resistance can be improved by nitriding the silicon dioxide thin film.

When comprehensively evaluated, samples S3-1 and S3-2 of the examples were all ⊚ (excellent) as products. Samples SR3-1 and SR3-2 of the comparative example were all x (failure).

In addition, the third embodiment (example) described above relates to an optical article in which a functional thin film is formed on a plastic spectacle lens having a hard coat layer. For optical articles having a glass substrate, it is also possible to form an antireflective layer on the substrate without a hard coat layer interposed between the substrate and the antireflective layer. The third embodiment of the present invention relates to a structure in which a silicon dioxide thin film whose surface has been nitrided is formed on the outermost layer. Embodiments have the same effect. In addition, the optical article is not limited to spectacle lenses, but includes optical elements such as optical elements of image display devices, prisms, optical fibers, elements for information recording media, and optical filters, and the above-described embodiments can also be applied to these optical articles. The disclosed manufacturing method.

Claims (7)

1. optical article, this optical article have the layer that comprises the part that via nitride handles, and the part that described via nitride is handled is the surface of the side of optical substrate dorsad of described layer, and described layer with SiO _xFor principal ingredient and directly be formed on the described optical substrate or between described layer and described optical substrate, accompany other layer of one deck at least.

2. optical article according to claim 1, wherein, the part that described via nitride is handled is Si _sO _tN _u, herein, s〉0, t ≧ 0, u〉0.

3. optical article according to claim 1, wherein, described optical article has anti-reflecting layer and directly is formed at stain-proofing layer on the described anti-reflecting layer, described anti-reflecting layer directly is formed on the described optical substrate or accompanies other layer of one deck at least between described anti-reflecting layer and described optical substrate, described anti-reflecting layer comprises the sublayer more than 2 layers, wherein, in the sublayer except the top layer of described anti-reflecting layer, at least one sublayer is the described layer that comprises the part that via nitride handles.

4. optical article according to claim 3, wherein, described anti-reflecting layer comprises the low-refraction sublayer more than 2 layers and is clipped at least one floor height refractive index sublayer between the described low-refraction sublayer more than 2 layers, and the one deck in the described low-refraction sublayer more than 2 layers is described top layer, and the one deck at least in other layer of described low-refraction sublayer more than 2 layers is the described layer that comprises the part that via nitride handles.

5. optical article according to claim 1, wherein, described optical article has anti-reflecting layer, and described anti-reflecting layer directly is formed on the described optical substrate or accompanies other layer of one deck at least between described anti-reflecting layer and described optical substrate; Described anti-reflecting layer comprises the sublayer more than 2 layers, and at least top layer is the described layer that comprises the part that via nitride handles in described sublayer more than 2 layers.

6. the manufacture method of an optical article, described optical article has functional layer, described functional layer directly is formed on the optical substrate or accompanies other layer of one deck at least between described functional layer and described optical substrate, and described functional layer comprises at least one sublayer; Described manufacture method has the operation that forms described functional layer, the operation of described formation functional layer comprises that layer forms operation and nitrogen treatment operation, it is to form the operation that is included in the sublayer in the described functional layer by vacuum evaporation that described layer forms operation, and the operation of described nitrogen treatment is the operation of the surface that forms a described sublayer that obtains in the operation at described layer being carried out nitrogen treatment.

7. the manufacture method of optical article according to claim 6, wherein, described nitrogen treatment operation comprises following content: the gas that will contain nitrogen imports and carries out described layer and form in the vacuum chamber of operation, and carries out Cement Composite Treated by Plasma or ion gun is handled.

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