JP2518116B2 - Method for manufacturing an optical body with excellent durability - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an optical body having various optical functions and having excellent durability.

[0002]

2. Description of the Related Art Conventionally, a thin film is formed on a transparent substrate such as glass or plastic to which an optical function is added to prevent reflection of a mirror, a heat ray reflecting glass, a low radiation glass, an interference filter, a camera lens or a spectacle lens. There is a coat.

In a normal mirror, Ag is formed by electroless plating.
Or Al or C by vacuum deposition method, sputtering method, etc.
r, etc. are formed. Among these, the Cr film is relatively strong and is therefore used as a part of a surface mirror having an exposed coated surface.

Titanium oxide, tin oxide and the like have been formed in the heat ray reflective glass by a spray method, a CVD method or a dipping method. Recently, a metal film, a nitride film, tin-doped indium oxide (ITO) or the like formed on a glass plate surface by a sputtering method has been used as a heat ray reflective glass. In the sputtering method, the film thickness can be easily controlled, and a plurality of films can be continuously formed. By combining with a transparent oxide film, it is possible to design the transmittance, reflectance, color tone and the like. For this reason, demand is increasing for construction, etc., where design is important.

Low-emissivity glass (low-emissivity glass) that reflects radiant heat from an indoor heater or wall to the inside of the room is a ZnO / Ag / ZnO three-layer system in which silver is sandwiched by zinc oxide or Zn.
5-layer system of O / Ag / ZnO / Ag / ZnO (Japanese Patent Application No. 61
280644), and is used in the form of double glazing or laminated glass. In recent years, it has been remarkably popular in cold regions of Europe.

The antireflection coating of a lens or the like is formed by alternately laminating a high refractive index film such as titanium oxide or zirconium oxide and a low refractive index film such as silicon oxide or magnesium fluoride. Usually, a vacuum vapor deposition method is used, and the substrate is heated during film formation to improve scratch resistance.

[0007]

Surface mirrors, antireflection coatings such as single-plate heat ray-reflecting glass and lenses are used with the coated film exposed to the air. Therefore, it must have excellent chemical stability and wear resistance. On the other hand, even low-emission glass may be defective due to scratches during transportation or handling before it becomes double glazing or laminated glass. Therefore, there is a demand for an optical thin film which is stable and has excellent wear resistance and which also serves as a protective film.

To improve durability, a chemically stable and transparent oxide film is usually provided on the air side. As these oxide films, there are titanium oxide, tin oxide, tantalum oxide, zirconium oxide, silicon oxide, etc., which have been selected and used according to the required performance.

However, although titanium oxide and zirconium oxide are excellent in chemical stability, they tend to form a crystalline film and tend to have large irregularities on the surface. Therefore, when they are rubbed, friction increases and abrasion resistance increases. Inferior in sex.

On the other hand, tin oxide and silicon oxide are weak in acid and alkali, respectively, and cannot withstand long-term immersion. Among them, tantalum oxide has both abrasion resistance and chemical stability, but it is not yet sufficient in terms of abrasion resistance.

Further, there has been an idea to provide an oxide containing zirconium or the like and silicon on a film formed on a soft and easily scratched substrate such as a plastic, but the plastic has good wear resistance and chemical stability. A glass substrate with a coated film that has excellent wear resistance and durability that can be used in almost the same way as a normal glass plate in applications where a glass substrate that is much higher than the glass substrate is used, such as automobiles and construction. The manufacturing method which can be provided was not known.

[0012]

The present invention has been made to solve the above-mentioned problems, and a transparent dielectric film, a nitride film, and an amorphous oxide film are formed on a glass substrate in this order from the glass substrate side. In the method for manufacturing an optical body in which at least three layers are formed, the outermost amorphous oxide film on the air side is titanium,
An amorphous oxide film containing at least one selected from the group of zirconium, hafnium, tin, tantalum, and indium, and an oxide containing silicon as a main component, and the three layers are sequentially formed by a sputtering method. The present invention provides a method for producing an optical body having excellent durability.

FIG. 1 shows a sectional view of an example of an optical body obtained by the present invention. 10 is a substrate made of transparent or colored glass, 11 is a first layer made of a transparent dielectric film, and 12 is a substrate. Indicates a second layer formed of a nitride film, and 13 indicates an amorphous oxide film forming an outermost layer on the air side, particularly a third layer formed of an oxide containing at least zirconium and silicon.

The present invention has at least a three-layer structure as described above, but in some cases, the substrate 10 and the first layer 11, the first layer 11 and the second layer 12, or the second layer 12 and the third layer shown in FIG.
One layer or a plurality of layers may be formed between the layer 13 and the layer 13 to have a function of improving the adhesive force, adjusting optical characteristics, or various other functions. In the present invention, an amorphous oxide film is formed on the outermost layer on the air side of the film formed on the glass substrate, and it can be used in applications requiring high durability, abrasion resistance and chemical stability. It realizes excellent glass.

The amorphous oxide film of the third layer 13 shown in FIG. 1 is amorphous when viewed from the X-ray, and specifically, from the group of titanium, zirconium, hafnium, tin, tantalum and indium. It is a composite oxide film containing at least one selected and silicon. Among these, a composite oxide film containing zirconium and silicon is particularly preferable because it has excellent scratch resistance and at the same time has sufficient chemical stability. The amorphous oxide film may contain at least one selected from the group consisting of titanium, zirconium, hafnium, tin, tantalum, and indium, and other components such as boron in addition to silicon and oxygen.

As an example, the case where an oxide containing zirconium and silicon is used for the third layer 13 is shown. in this case,
The content ratio of silicon is not particularly limited. The refractive index of this film decreases from 2.1 to 1.8 or less as the content ratio of silicon increases, but both the abrasion resistance and the chemical stability are good. Therefore, the silicon content may be selected based on the refractive index that is optically required. Generally, 1 part or more, preferably 3 parts or more, and particularly 5 parts or more of silicon is desirable in atomic ratio with respect to 100 parts of zirconium. If the amount of silicon is less than this, sufficient amorphization cannot be obtained, so that the wear resistance performance deteriorates, and the superiority over ordinary zirconium oxide containing no silicon cannot be recognized.

On the other hand, the upper limit of the silicon content is not particularly limited, but an atomic ratio of 2000 parts or less, preferably 1000 parts or less, and particularly 500 parts or less is desirable with respect to 100 parts of zirconium. If the amount of silicon is larger than this, the refractive index becomes extremely small, the chemical stability becomes insufficient, and the abrasion resistance also decreases, which is not preferable.

The oxide film containing zirconium and silicon is not limited to the three components of zirconium, silicon and oxygen, and has improved durability, adjustment of optical constants, stability during film formation, or film formation. Other components may be included to improve speed and the like. Further, the amorphous oxide film of the present invention does not necessarily have to be transparent, and it is similarly effective even if it is an absorptive film in a state of oxygen deficiency or partially contains nitrogen.

The film thickness of the third layer 13, which is the outermost layer, is not particularly limited. It may be determined in consideration of the transmission color and the reflection color depending on the application, but if it is too thin, sufficient durability cannot be obtained, so it is preferably 50 Å or more, preferably 100 Å or more, and particularly 200 Å or more.

A sputtering method is used as a method for forming the third layer 13, and when a large area coating such as heat ray reflective glass for automobiles or construction is required, a reactive sputtering method having excellent uniformity is preferable.

In the present invention, another layer is formed between the substrate and the nitride film in order to increase the adhesion with the glass interface.
It is important to have a three-layer structure as described below. Such first
The layer 11 is preferably a transparent dielectric film made of an oxide such as titanium oxide, zirconium oxide, hafnium oxide, tin oxide, tantalum oxide, indium oxide, or zinc sulfide.

Considering the adhesion to the nitride film of the second layer 12 and the productivity by sputtering, a dielectric film containing the same element as the nitride film of the second layer is preferable, but it is not particularly limited thereto. However, the combination of the first layer 11 and the second layer 12 may be various, such as tantalum oxide / titanium nitride, zirconium oxide / titanium nitride, or tin oxide / zirconium nitride. The transparent dielectric film of the first layer 11 may be the same as the above-described amorphous oxide film.

Although the film thickness of the dielectric film 11 is not particularly limited, these dielectrics also have a large refractive index, and if an appropriate film thickness is selected, the interference effect can also be used to adjust the reflectance and color tone. Is. In particular, when used in a heat ray reflective glass for the purpose of high transmission and low reflection in the visible region by utilizing the interference effect, the film thickness of the first layer 11 and the third layer 13 is an optical film thickness of 10
It is preferably adjusted in the range of 00 to 1800Å. The refractive indices of the first layer 11 and the third layer 13 are preferably selected in the range of 2.0 to 2.5, but even if the refractive index is out of this range, the optical film thickness may be in a proper range.

The film thickness of the nitride film of the second layer 12 is preferably 1000 Å or less, though it depends on the desired transmittance, and is 50 to 50.
The optimum range is 500Å. If it exceeds 1000 Å, absorption of the nitride film becomes too large, and peeling easily occurs due to internal stress.

When the outermost layer of the second layer 3 or the third layer 13 is an oxide film containing zirconium and silicon, it is between the first layer 2 and the second layer 3 or between the second layer 12 and the third layer 13. In order to improve the interlayer adhesion of the layer 13 and to reduce the internal stress of the first layer 2 or the second layer 12, a nitride containing silicon, particularly zirconium siliconitride, is used as the first layer 2 or the second layer 12. It is effective to use.

In the present invention, the optical thin film may be formed on only one surface of the substrate as shown in FIG. 1, or may be formed on both surfaces of the substrate.

[0027]

The amorphous oxide film which is the outermost layer on the air side of the optical body in the present invention, that is, the third layer 13 in FIG. 1, is made amorphous by containing silicon which is a constituent element of the glass. Since the surface smoothness is increased, the frictional resistance is reduced, which has high durability. Therefore, in the optical body of the present invention,
It has a role of a protective layer to improve abrasion resistance and chemical resistance. Further, by adjusting the refractive index and the film thickness, it has an optical function, that is, an adjusting function such as transmittance, reflectance and color tone.

In particular, when the outermost layer is an oxide film containing zirconium and silicon, the film is amorphous by adding silicon to zirconium oxide having a strong chemical stability against acids, alkalis and the like. It contributes to the realization of a film that has improved quality and has extremely excellent durability that satisfies both wear resistance and chemical stability.

Silicon also contributes to the adjustment of the refractive index of the film. That is, the refractive index can be lowered by increasing the content ratio of silicon. In the present invention, the layers other than the outermost layer mainly have an optical function and are responsible for transmission and reflection performance.

Further, in the optical body having a heat ray reflecting property, the nitride film has a heat ray reflecting function. Further, in the heat ray reflective glass aiming at high transmission and low reflection in the visible region by utilizing the interference effect, the second layer 12 of FIG.
Is responsible for the heat ray reflection function, and includes the first layer 11 and the third layer 13
Has a function of preventing reflection of the nitride film in the visible range.

[0031]

Example [Example 1] A glass substrate was set in a vacuum chamber of a sputtering apparatus,
It was evacuated to 1 × 10 ⁻⁶ Torr. After introducing a mixed gas of argon and oxygen to a pressure of 2 × 10 ⁻³ Torr,
Zirconium target containing silicon (atomic ratio Zr / Si
= 33/67) a high-frequency magnetron sputtering to amorphous oxide film ZrSi _x O _y (first layer) approximately 600Å
Formed. Next, a titanium target was subjected to high-frequency magnetron sputtering by switching to a mixed gas of argon and nitrogen at a pressure of 2 × 10 ⁻³ Torr, and titanium nitride (second
Layer) was formed by about 50Å. After that, a ZrSi _x O _y film (third layer) was formed again at about 600 Å under the same conditions as the first layer.

The visible light transmittance T _V , the solar light transmittance T _E , the coat surface visible light reflectance R _VF , and the glass surface visible light reflectance R _VG of the heat ray reflective glass thus obtained were each about 8
It was 0, 72, 7, 10 (%). 6 hours in 1N hydrochloric acid, sodium hydroxide to check the durability of the membrane,
Alternatively, when immersed in boiling water for 2 hours, the change in transmittance and reflectance was within 1% in both cases.

Even in a rubbing test using a sand eraser (plus company eraser No. 48-100, facing a razor cut surface having a diameter of 5 mm, applying a load of 500 g, and reciprocating 5 times at 50 mm / min), scratches are scarcely observed and extremely excellent. It also showed wear resistance.

Further, a wear resistance test (Taber test, wear wheel CS-10F, JIS R3212,
When subjected to a load of 500 g and 1000 rotations), the change ΔT _V in visible light transmittance T _V before and after the test and the change ΔH in haze value were both within 4%, which showed excellent wear resistance performance.

[Example 2] A glass substrate was set in a vacuum chamber of a sputtering apparatus,
It was evacuated to 1 × 10 ⁻⁶ Torr. After introducing a mixed gas of argon and oxygen to a pressure of 2 × 10 ⁻³ Torr,
Amorphous oxide film TiSi _x O _y film (first
Layer) was formed to about 600Å.

Next, a titanium target (high frequency magnetron sputtering) was carried out by switching to a mixed gas of argon and nitrogen at a pressure of 2.times.10.sup.- ³ Torr to form titanium nitride (second layer) in an amount of about 50. After that, the amorphous oxide film TiSi _x O _y (third layer) is again about 60 under the same conditions as the first layer.
0Å formed. Visible light transmittance of the sample thus obtained,
The solar transmittance was almost the same as that of Example 1.
With respect to durability, the same results as in Example 1 were obtained.

Comparative Example 1 In order to see the effect of Example 1, a zirconium oxide film (first layer) containing no silicon was formed on the surface of the glass substrate at about 600 liters. Next, a titanium target was subjected to high-frequency magnetron sputtering by switching to a mixed gas of argon and nitrogen at a pressure of 2 × 10 ⁻³ Torr, and titanium nitride (second
Layer) was formed by about 50Å. After that, a zirconium oxide film (third layer) was formed again at about 600Å under the same conditions as the first layer. When the sample thus obtained was subjected to a sand eraser test, it was inferior in abrasion resistance and many scratches were generated.

Comparative Example 2 In order to see the effect of Example 2, a titanium oxide film (first layer) containing no silicon was formed on the surface of the glass substrate to a thickness of about 600 liters. Next, the titanium target (second layer) was formed to a thickness of about 50 Å by high-frequency magnetron sputtering of a titanium target while switching to a mixed gas of argon and nitrogen at a pressure of 2 × 10 ^-3 Torr. After that, a titanium oxide film (third layer) was formed again to about 600 Å under the same conditions as the first layer. When the sample thus obtained was subjected to a sand eraser test, it was inferior in abrasion resistance and many scratches were generated.

[0039]

INDUSTRIAL APPLICABILITY The present invention uses an amorphous oxide film as the outermost layer as viewed from the glass substrate, that is, the outermost layer on the air side. It is possible to obtain an optical body excellent in chemical stability and abrasion resistance that is not so different from the above. As a result, the optical body of the present invention can be used for severe applications that could not be used conventionally.

When an amorphous oxide film containing silicon is used, the refractive index of the oxide film can be adjusted by changing the content ratio of silicon, and the degree of freedom in optical film design is increased. It also has the effect of expanding.

[Brief description of drawings]

FIG. 1 is a partial sectional view of an example of an optical body obtained by the present invention.

[Explanation of symbols]

10: glass substrate, 11: transparent dielectric film (first layer), 1
2: nitride film (second layer), 13: amorphous oxide film (third layer)
layer).

Claims (3)

(57) [Claims] 1. A glass substrate, in order from the glass substrate side.
At least 3 of transparent dielectric film, nitride film, and amorphous oxide film
In the method for producing a layered optical body , the outermost amorphous oxide film on the air side includes at least one selected from the group consisting of titanium, zirconium, hafnium, tin, tantalum, and indium, and silicon. Ri Do amorphous oxide film composed mainly of an oxide containing, sputtering the three layers
A method for manufacturing an optical body having excellent durability, which is characterized in that the optical body is sequentially formed by a method . 2. The amorphous oxide film is an oxide film containing at least zirconium and silicon.
A method for producing an optical body having excellent durability as described above. 3. A nitride film is a titanium nitride, excellent in the durability of claim 1, wherein in that it consists of at least one selected zirconium nitride, hafnium nitride, from the group of tantalum nitride and chromium nitride How to make optics
Law .