JP2009093067A - Zirconium oxide layer, scratch-resistant article and optical article - Google Patents

Abstract

A scratch-resistant article comprising a zirconium oxide layer having an ultrahigh refractive index, a surface layer comprising the zirconium oxide layer, and an optical article comprising an antireflection layer comprising the zirconium oxide layer, which did not exist so far. provide.
The zirconium oxide layer of the present invention has a refractive index of 2.0 or more at a wavelength of 550 nm. An article in which the zirconium oxide layer is formed on a predetermined substrate exhibits excellent scratch resistance. A multilayer film composed of a high refractive index layer made of the zirconium oxide layer and a low refractive index layer exhibits an excellent antireflection effect.
[Selection figure] None

Description

  The present invention relates to a high-refractive-index zirconium oxide layer, a scratch-resistant article and an optical article provided with a surface layer composed of the zirconium oxide layer.

In recent years, optical articles intended for light transmission, such as various lenses and covers for various displays such as mobile phone display boards, have been developed to suppress light reflection and increase light transmission. An antireflection layer is formed on the surface. In particular, in lenses such as eyeglasses and cameras, the higher the refractive index, the higher the reflectance of light on the surface. Therefore, inorganic thin layers having different refractive indices are laminated alternately to make use of the light interference effect. Antireflection layers are widely used.
A substance used for forming such an inorganic antireflection layer is an inorganic oxide (metal oxide). In particular, an inorganic antireflection layer having a wide band is often used by adjusting the film thickness of a silicon oxide (SiO ₂ ) layer and a zirconium oxide (ZrO ₂ ) layer and alternately laminating these layers. (For example, refer to Patent Document 1).

JP 2002-122820 A

However, in the antireflection layer formed from the ZrO ₂ layer and the SiO ₂ layer described in Patent Document 1, the refractive index of the ZrO ₂ layer is not so high as 1.99. If the refractive index of the ZrO ₂ layer is low, there is a problem that the antireflection effect is low. Also, the low refractive index means that the density and hardness are low at the same time, which means that the scratch resistance of the ZrO ₂ layer is not sufficient, and as a result, the scratch resistance as a lens is not sufficient. It was.
Therefore, the present invention has been made in view of such circumstances, and an ultrahigh-refractive-index zirconium oxide layer, a scratch-resistant article provided with a surface layer composed of the zirconium oxide layer, and An object is to provide an optical article provided with an antireflection layer comprising a zirconium oxide layer.

As a result of earnest research, the present inventor succeeded in obtaining a zirconium oxide layer having an ultrahigh refractive index by utilizing ion-assisted deposition under predetermined conditions, and completed the present invention based on the knowledge. .
That is, the present invention is a zirconium oxide layer characterized by having a refractive index of 2.0 or more at a wavelength of 550 nm.
The zirconium oxide layer of the present invention has a refractive index of 2.0 or higher, and has a higher refractive index than the conventionally known zirconium oxide layers. Therefore, if the zirconium oxide layer of the present invention is formed as a thin layer on the surface of an appropriate article, an article having extremely excellent scratch resistance can be obtained. Furthermore, by forming the zirconium oxide layer of the present invention as a high refractive index layer and alternately laminating with an appropriate low refractive index layer, an antireflection layer having at least a very high antireflection effect can be provided. . Therefore, it is possible to easily obtain an optical article that is extremely excellent in the antireflection effect.
In the present invention, the refractive index of the zirconium oxide layer is preferably 2.01 or more, and more preferably 2.02 or more. However, if the refractive index becomes too high, the zirconium oxide layer becomes too dense and the internal stress becomes high and the zirconium oxide itself may become brittle. Therefore, the refractive index of the zirconium oxide layer is 2.1 or less. It is preferable that it is 2.08 or less.

In the present invention, the zirconium oxide layer is preferably formed on a predetermined substrate by ion-assisted deposition while introducing nitrogen gas, argon gas, or a mixed gas thereof.
According to the present invention, since ion-assisted deposition is performed while introducing a predetermined gas, a zirconium oxide layer having a refractive index of 2.0 or more can be easily obtained.

The present invention relates to a scratch-resistant article comprising a substrate and a thin layer formed thereon, wherein the thin layer comprises a single layer film or a multilayer film, and the single layer film and the multilayer film include at least zirconium oxide. And the zirconium oxide layer is any one of the above-described zirconium oxide layers.
According to the scratch-resistant article of the present invention, since the refractive index of the zirconium oxide layer is as extremely high as 2.0 or more, the density and hardness of the zirconium oxide layer itself is high and formed as a thin layer on the substrate. The product is extremely excellent in scratch resistance. The high refractive index zirconium oxide layer does not necessarily need to be present on the outermost surface of the article. For example, even when a layer such as an antifouling layer is separately provided as the outermost surface layer, it contributes sufficiently to improving the scratch resistance.

The optical article of the present invention includes an optical article having a light-transmitting substrate and an antireflection layer in which a plurality of high refractive index layers and low refractive index layers are alternately laminated on at least one surface of the substrate. And the high refractive index layer is formed of any one of the above-described zirconium oxide layers.
According to the optical article of the present invention, since the refractive index of the zirconium oxide layer is as extremely high as 2.0 or more, the antireflection layer formed by alternately laminating the zirconium oxide layer and a suitable low refractive index layer, An excellent antireflection effect can be exhibited with a smaller number of layers.

  Hereinafter, embodiments of the present invention will be described in detail. The optical article according to the present embodiment is a plastic spectacle lens (hereinafter also referred to as “glass spectacle lens” or simply “lens”) having an inorganic antireflection layer on the surface.

[Configuration of eyeglass lens]
FIG. 1 is a cross-sectional view schematically showing the configuration of the spectacle lens 100. In the spectacle lens 100, an inorganic antireflection layer 43 composed of a multilayer layer is formed on a lens substrate 40, and an antifouling layer 44 is further formed thereon. The lens substrate 40 is formed of a plastic substrate 41 and a hard coat layer 42.

In the inorganic antireflection layer 43, the low refractive index material layer (L) is composed of SiO ₂ (n = 1.45), and the high refractive index material layer (H) is composed of ZrO ₂ (n ≧ 2.0). As shown in FIG. 1, the inorganic antireflection layer 43 is formed by first laminating a low refractive index material SiO ₂ layer 431 from the side in contact with the hard coat layer 42, and a high refractive index material ZrO ₂ layer 432 on the upper surface thereof. In the following, the inorganic antireflection layer 43 consisting of a total of five layers is formed by alternately laminating the SiO ₂ layer 433, the ZrO ₂ layer 434, and the SiO ₂ layer 435.

[Method of Manufacturing Eyeglass Lens 100]
FIG. 2 is a diagram schematically showing a vapor deposition apparatus 50 for manufacturing the spectacle lens 100. Hereinafter, the structure of the vapor deposition apparatus 50 and the manufacturing method of the spectacle lens 100 by forming the inorganic antireflection layer 43 and the antifouling layer 44 on the substrate 40 will be described in detail.

(Structure of the vapor deposition apparatus 50)
3A and 3B show an outline of a support device 80 on which the lens substrate 40 is mounted. The support device 80 includes a disk-shaped dome 81 that is convexly convex upward, and a plurality of lens substrates 40 are arranged concentrically on the dome 81 and can be rotated while maintaining the arrangement. Yes. In the support device 80 shown in FIG. 3A, a plurality of lens substrates 40 serving as spectacle lenses can be set concentrically around the rotation shaft 82 in one to four stages.

  The inorganic antireflection layer 43 is formed on the lens substrate 40 by ion-assisted vapor deposition by the vapor deposition apparatus 50 shown in FIG. The vapor deposition device 50 includes three chambers CH1, CH2, and CH3 through which the support device 80 can pass. These chambers CH <b> 1 to CH <b> 3 are connected, and can pass through the support device 80 while holding the lens substrate 40. The chambers CH1 to CH3 can be sealed with each other, and the internal pressures of the chambers CH1 to CH3 can be controlled by the vacuum generators 52, 53, and 54, respectively.

  The chamber CH1 is an entrance or gate chamber, and after introducing the support device 80 from the outside, the chamber CH1 is degassed by holding the inside of the chamber CH1 below a certain pressure for a certain time. The chamber CH1 is provided with a vacuum generating device 52 including a rotary pump 52a, a roots pump 52b, and a cryopump 52c.

The chamber CH2 is a second chamber in which the inorganic antireflection layer (AR layer) 43 is formed. For this reason, inside the chamber CH2, AR layer deposition sources 55a and 55b, an electron gun 56 for depositing the AR layer deposition sources 55a and 55b, and an openable / closable shutter 57 for adjusting the deposition amount are provided. . The AR layer 43 includes a thin layer mainly composed of silicon oxide (SiO ₂ ) and ZrO ₂ (if necessary, TiO ₂ , Nb ₂ O ₃ , Ta ₂ O _5, etc.) as a main component. It is the structure formed by alternately laminating thin layers. For this reason, at least two vapor deposition sources 55a and 55b are prepared. The chamber CH2 is maintained at an appropriate pressure by a vacuum generation device 53 including a rotary pump 53a, a roots pump 53b, and a cryopump 53c.

  The chamber CH3 is a third chamber for forming an antifouling outermost layer by depositing a fluorine-containing organosilicon compound. Therefore, an evaporation source impregnated with a fluorine-containing organosilicon compound, a heater (halogen lamp), and a correction plate are installed inside the chamber (not shown). The correction plate is a fixed type, and the amount of vapor deposition emitted toward the support device 80 can be adjusted by adjusting the opening degree. The chamber CH3 is maintained at an appropriate pressure by a vacuum generator 54 including a rotary pump 54a, a roots pump 54b, and a turbo molecular pump 54c.

(Formation of inorganic antireflection layer 43)
Below, the preferable vapor deposition conditions at the time of using the vapor deposition apparatus 50 are demonstrated.
First, the first layer is formed by depositing silicon oxide on the substrate 40. In the second layer, zirconium oxide having a high refractive index is deposited by irradiating ions simultaneously with vapor deposition of zirconium oxide. As the introduced gas at this time, nitrogen gas or argon gas is used alone, or a mixed gas containing each of them in an arbitrary ratio is used. Further, the acceleration voltage at this time is adjusted in the range of 200 to 1000 V, the acceleration current is 50 to 300 mA, the bias current is 1.5 to 3.0 times the acceleration current value, and the gas flow rate is in the range of 15 to 25 sccm. However, an acceleration voltage of 600 to 1000 V, an acceleration current of 150 to 300 mA, a bias current of 1.5 times the acceleration current, and a gas flow rate of about 20 sccm are preferable from the viewpoint of improving the refractive index of the zirconium oxide layer. Among these conditions, an acceleration voltage of 800 to 1000 V and an acceleration current of 240 to 260 mA are particularly preferable.

After the silicon oxide layer is formed as the third layer, zirconium oxide is vapor-deposited in the fourth layer and simultaneously irradiated with ions. The ion irradiation conditions (acceleration voltage, acceleration current, bias current, introduced gas type, introduced gas flow rate) at this time are not necessarily the same as those in the second layer. After forming the fourth layer, a fifth silicon oxide layer is formed. Thereafter, an antifouling layer 44 described later is formed on the outermost surface.
Here, ion-assisted deposition may be performed only on the second layer or the fourth layer. That is, any one of the second and fourth layers may be formed by ion-assisted deposition. Of course, it is most effective to form all the zirconium oxide layers by ion-assisted deposition.

(Formation of antifouling layer 44)
After moving the support device 80 to the chamber CH3, the antifouling layer 44 is formed as follows. First, a suitable fluorine-containing organosilicon compound (for example, KY-130 manufactured by Shin-Etsu Chemical Co., Ltd.) is diluted in a fluorine-based solvent (for example, Sumitomo 3M Limited: Novec HFE-7200) to obtain a solid content concentration of 2 A 4% by mass solution is prepared, and about 0.5 to 2 g of impregnated porous ceramic pellets and dried are used as a deposition source.
This vapor deposition source is set in the chamber CH3. Next, using a halogen lamp as a heater, the vapor deposition source pellet is heated to 500 to 700 ° C. to evaporate the fluorine-containing organosilicon compound. The deposition time is 2 to 4 minutes, and the antifouling layer 44 is formed on the surface of the lens substrate 40 (antireflection layer 43).
When it is desired to form the antireflection layer 43 and / or the antifouling layer 44 on both surfaces of the lens substrate 40, after forming the antireflection layer 43 and / or the antifouling layer 44, the support device 80 is taken out of the chamber and the lens is inverted. Then, the antireflection layer 43 and / or the antifouling layer 44 are formed on both surfaces of the lens substrate 40 by setting the dome 81 of the support device 80 with the convex surface down and performing the same process as described above again.

According to the above-described embodiment, there are the following effects.
(1) Since the refractive index of the zirconium oxide layers 432 and 434 constituting the antireflection layer 43 is as extremely high as 2.0 or more, the spectacle lens 100 having high density and hardness and extremely excellent scratch resistance can be provided.
(2) The antireflection layer 43 of the spectacle lens 100 is formed by alternately stacking zirconium oxide layers 432 and 434 having a refractive index of 2.0 or more and low refractive index layers (silicon oxide layers) 431, 433, and 435. Therefore, even if the number of stacked layers is 5, an excellent antireflection effect can be exhibited.
(3) The method of forming the zirconium oxide layers 432 and 434 is known ion-assisted deposition, and the gas used is nitrogen gas or argon gas. Rate zirconium oxide layers can be produced.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the present embodiment, an example in which a spectacle lens is selected as an optical article and applied to the antireflection layer has been described, but in addition, various other types such as a camera lens, a telescope lens, a microscope lens, and a stepper condenser lens are used. It can be widely applied to thin optical lenses. Moreover, the present invention can be widely applied not only to optical articles but also to various articles that require scratch resistance.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples. In each example, devices having the same structure and function as those in the embodiment will be described with the same reference numerals.
[Example 1]
In this example, the spectacle lens 100 was manufactured by setting specific conditions in the above-described embodiment. As the plastic substrate 40 of the spectacle lens 100, a Seiko super sovereign made by Seiko Epson Corporation and having a hard coat layer 42 formed thereon was used. Hereinafter, specific conditions for forming the inorganic antireflection layer 43 and the antifouling layer 44 on the substrate 40 will be described.

(Formation of inorganic antireflection layer 43)
Hereinafter, a specific method for forming the inorganic antireflection layer 43 will be described.
First, the lens substrate 40 was set on the dome 81 of the support device 80 with the concave surface thereof facing down. Next, after degassing in the chamber CH1 set at a temperature of 60 ° C., ion cleaning was performed in the chamber CH2 for 2 minutes under the conditions of an acceleration voltage of 500 V, an acceleration current of 250 mA, a bias current of 380 mA, and an oxygen gas introduction flow rate of 20 sccm. This is intended to clean the surface of the lens substrate 40 in order to improve the adhesion between the lens substrate 40 and the antireflection layer.

Subsequently, an inorganic antireflection layer 43 was formed. The detailed stratification procedure is as follows. First, a silicon oxide (SiO ₂ ) layer 431 was formed as a first layer by vacuum deposition. Thereafter, the degree of vacuum is set to be around 6.0 × 10 ⁻³ Pa, the second layer has an acceleration voltage of 800 V, an acceleration current of 250 mA, a bias current of 1.5 times the acceleration current (375 mA), and a nitrogen gas of 20 sccm. Then, ion-assisted vapor deposition was performed while introducing Zr to form a zirconium oxide layer 432. Then, a silicon oxide layer 433 similar to the first layer was formed as a third layer by vacuum deposition. Next, as the fourth layer, ion-assisted vapor deposition was performed under the same conditions as the second layer to form a zirconium oxide layer 434. Finally, a silicon oxide layer 435 was formed as the fifth layer by vapor deposition. As a result, an inorganic antireflection layer 43 consisting of a total of five layers was formed on the lens substrate 40.

After vapor deposition, 100% oxygen gas was introduced into the chamber, and plasma was generated by a high-frequency plasma generator while controlling the pressure at 4.0 × 10 ⁻² Pa. Plasma generation conditions were 13.56 MHz and 400 W, and the treatment was performed for 2 minutes. The purpose of this is to activate the surface of the inorganic antireflection layer 43 and promote chemical bonding with the antifouling layer 44 in the next step.

(Formation of antifouling layer 44)
After moving the support device 80 to the chamber CH3, the antifouling layer 44 was formed as follows.
First, a fluorine-containing organosilicon compound represented by the following formula (1) (KY-130 manufactured by Shin-Etsu Chemical Co., Ltd.) is diluted with a fluorine-based solvent (Sumitomo 3M Co., Ltd .: Novec HFE-7200) to obtain a solid content concentration. A vapor deposition source 59 was prepared by preparing a 3% by mass solution, impregnating 1 g of the porous ceramic pellets and drying it.

（式中、Ｒｆ^２は、式：−（Ｃ_ｋＦ_２ｋ）Ｏ−（前記式中、ｋは１〜６の整数である）で示される単位を含み、分岐を有しない直鎖状のパーフルオロポリアルキレンエーテル構造を有する２価の基である。Ｒ^３は炭素原子数１〜８の一価炭化水素基であり、Ｘは加水分解性基またはハロゲン原子である。ｐは０、１、２のいずれかである。ｎは１〜５の整数である。ｍおよびｒは２または３である。）

(In the formula, Rf ² includes a unit represented by the formula: — (C _k F _2k ) O— (wherein k is an integer of 1 to 6), and is a straight-chain par having no branch. A divalent group having a fluoropolyalkylene ether structure, R ³ is a monovalent hydrocarbon group having 1 to 8 carbon atoms, X is a hydrolyzable group or a halogen atom, p is 0, 1, And n is an integer of 1 to 5. m and r are 2 or 3.)

This deposition source 59 was set in the chamber CH3. Next, using a halogen lamp as the heater 68, the pellet of the vapor deposition source 59 was heated to 600 ° C. to evaporate the fluorine-containing organosilicon compound. The antifouling layer 44 was formed on the surface of the lens substrate 40 (antireflection layer 43) with a deposition time of 3 minutes.
After the antifouling layer 44 is formed, the support device 80 is taken out of the chamber, the lens is inverted and set on the dome 81 of the support device 80 with the convex surface down, and the same processing as described above is performed again. An antireflection layer 43 and an antifouling layer 44 were formed on both sides of the film.

[Example 2]
During the formation of the zirconium oxide layer, 20 sccm of argon gas was introduced to perform ion-assisted deposition. Other operations and conditions are the same as those in the first embodiment.

Example 3
When forming the zirconium oxide layer, ion-assisted deposition was performed by introducing 15 sccm of nitrogen gas and 5 sccm of argon gas. Other operations and conditions are the same as those in the first embodiment.

[Comparative Example 1]
In Example 1, the degree of vacuum was set to be around 2.0 × 10 ⁻³ Pa, and the zirconium oxide layer was formed without ion assist. That is, the antireflection layer was formed by simple vapor deposition without performing any ion assist. Other operations and conditions are the same as those in the first embodiment.

[Comparative Example 2]
During the formation of the zirconium oxide layer, 20 sccm of oxygen gas was introduced to perform ion-assisted deposition. Other operations and conditions are the same as those in the first embodiment.

[Comparative Example 3]
In Comparative Example 1, the degree of vacuum during vapor deposition was set to be around 4.0 × 10 ⁻⁴ Pa.
Other operations and conditions are the same as those in the first embodiment.

〔Evaluation methods〕
The physical properties of the plastic spectacle lenses (hereinafter also simply referred to as “lenses”) obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were evaluated by the evaluation methods shown below. Evaluation items are refractive index and scratch resistance. The results are shown in Table 1.

(1) Refractive index A zirconium oxide layer having a thickness of 100 nm was formed on the BK7 glass substrate under the above-described conditions, and the refractive index was measured with a spectroscopic ellipsometer (manufactured by SOPRA). The measurement wavelength is 550 nm.
(2) Scratch resistance (Bayer test)
Using a Bayer testing machine manufactured by COLTS Laboratories, the test product (eyeglass lens) manufactured under the above-mentioned conditions and a standard lens (manufactured by SANLUX Co., Ltd .: CR39) were reciprocated 600 times with a medium of 500 g in mass and simultaneously damaged. (Standard conditions specified by COLTS Laboratories). The haze value (automatic haze computer manufactured by Suga Test Instruments Co., Ltd.) of the scratched lens is measured, and the Bayer Ratio R is calculated by the ratio of the haze value change between the test product and the standard lens by the following formula. Calculation and evaluation of scratch resistance were performed.
R = | H _ST1 −H _ST0 | / | H _SA1 −H _SA0 |
Here, H is a haze value, ST is the above-mentioned standard lens, and SA is a test spectacle lens. ST0 and SA0 mean before test, and ST1 and SA1 mean after test. The greater the R value, the better the scratch resistance. Incidentally, the _media, ZrO 2: 21 to 23 _{wt%, Al} 2 O 3: _{73~77 wt%,} HfO 2: is a sand-like particles of hard having a composition of 0.3-1.3 wt%.
R was calculated by measuring three test samples and three standard lenses, and the average value was taken as the measurement value.

〔Evaluation results〕
From the results in Table 1, it can be seen that in the spectacle lens of the present invention, the refractive index of the zirconium oxide layer is as extremely high as 2.0 or more and the scratch resistance is very excellent. On the other hand, in Comparative Example 1, ion assist was not performed when the zirconium oxide layer was formed, and since the deposition was merely vapor deposition, the refractive index of the zirconium oxide layer was not improved. In Comparative Example 2, ion-assisted deposition was performed while introducing oxygen gas, but the refractive index did not increase so much because ZrO ₂ and oxygen atoms reacted. In Comparative Example 3, the degree of vacuum was increased in Comparative Example 1, but the degree of improvement in the refractive index of the zirconium oxide layer and the improvement in scratch resistance of the spectacle lens were slight.

  The present invention can be suitably used in the field of optical articles such as eyeglass lenses.

Sectional drawing of the spectacle lens which concerns on this embodiment. The figure which shows the vapor deposition apparatus for manufacturing spectacle lenses in this embodiment. The figure which shows the board | substrate support apparatus mounted in the inside of a vapor deposition apparatus in this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 40 ... Lens substrate, 41 ... Plastic substrate, 42 ... Hard coat layer, 43 ... (Inorganic) antireflection layer, 44 ... Antifouling layer, 50 ... Deposition apparatus, 52, 53, 54 ... Vacuum generation apparatus, 52a, 53a, 54a ... Rotary pump, 52b, 53b, 54b ... Roots pump, 52c, 53c ... Cryo pump, 54c ... Turbo molecular pump, 55a, 55b ... AR layer deposition source, 56 ... Electron gun, 57 ... Shutter, 80 ... Supporting device, 81 ... Dome, 82 ... Rotating shaft, 100 ... Eyeglass lens, 431, 433, 435 ... Silicon oxide layer, 432, 434 ... Zirconium oxide layer

Claims (5)

  A zirconium oxide layer having a refractive index of 2.0 or more at a wavelength of 550 nm. In the zirconium oxide layer according to claim 1,
The zirconium oxide layer having a refractive index of 2.01 or more and 2.1 or less. In the zirconium oxide layer according to claim 1 or 2,
A zirconium oxide layer, wherein the zirconium oxide layer is formed on a predetermined substrate by ion-assisted deposition while introducing nitrogen gas, argon gas, or a mixed gas thereof. A scratch-resistant article comprising a substrate and a thin layer formed thereon,
The thin layer consists of a single layer film or a multilayer film,
The single layer film and the multilayer film include at least a layer made of zirconium oxide,
The scratch-resistant article, wherein the zirconium oxide layer is the zirconium oxide layer according to any one of claims 1 to 3. A substrate having optical transparency;
In an optical article having an antireflection layer in which a plurality of high refractive index layers and low refractive index layers are alternately laminated on at least one surface of the substrate,
An optical article, wherein the high refractive index layer comprises the zirconium oxide layer according to any one of claims 1 to 3.

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