JPH0351802A - Production of multilayered antireflection film - Google Patents

Abstract

PURPOSE:To improve productivity and workability by interposing a specific deposition preventive plate for successively and continuously forming a perpendicularly vapor-deposited film and diagonally vapor-deposited film in the flow direction of a film base material between a vapor deposition roll and an evaporating source. CONSTITUTION:The device is constituted to execute the vacuum deposition of the evaporating source 6 on the vapor deposition roll 4 onto the film base material 5. The deposition preventive plate 7 having a through-hole for forming the perpendicularly vapor-deposited film and a through-hole 7a for forming the diagonally vapor-deposited film is interposed between the vapor deposition roll 4 and the evaporating source 6. The perpendicularly vapor-deposited film is first formed in the part 4A on the vapor deposition roll 4 via the through-hole 7a of the deposition preventive plate 7 and further, the diagonally vapor-deposited film is formed in the part 4b on the vapor deposition roll 4 through the through-hole 7b of the deposition preventive plate 7. Namely, the 1st layer consisting of a dielectric layer 60A of a high refractive index which is the perpendicularly vapor-deposited film is formed on the film base material 5 and the 2nd layer consisting of a dielectric layer 60B having of a low refractive index which is the diagonally vapor-deposited film are successively and continuously laminated and formed in this order. The films are thus formed with good productivity and workability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a multilayer antireflection film using a winding type vacuum deposition apparatus.

[Conventional technology]

An antireflection film used for various computer displays and TV cathode ray tubes, etc., has a two-layer structure on a base film, with a first layer made of a high refractive index dielectric and a second layer made of a low refractive index dielectric. One with layers is known.

When forming such an antireflection layer using a vacuum evaporation method, different types of dielectric materials are required to form the first layer and the second layer, and both layers must be formed in order. In this case, the vapor deposition apparatus leaks after the formation of the first layer, requiring troublesome procedures such as changing the evaporation source, cleaning the vapor deposition apparatus, and evacuation, resulting in a disadvantage that the workability is significantly inferior.

For this reason, production equipment has conventionally been equipped with a winding type vacuum evaporation system that can form a dielectric layer over a large area at one time, that is, a winding type vacuum evaporation system that is electrically connected between a supply roll and a winding roll in a vacuum chamber. A vapor deposition apparatus has been developed that continuously performs vacuum vapor deposition of an evaporation source on the above-mentioned vapor deposition roll onto a film base material flowing along the surface of the vapor deposition roll.

[Problem to be solved by the invention]

However, although it is possible to improve productivity to some extent by using such a winding type vacuum evaporation apparatus, the first layer and the second layer must still be formed separately. It is still necessary to change the evaporation source and clean the evaporation equipment accordingly, and these procedures tend to be more complicated than in batch-type equipment.

By the way, the inventors first discovered 1. We noticed that when a dielectric material with a high refractive index, such as ZrO, is deposited obliquely to a film substrate, its refractive index becomes lower than when normal vertical deposition is performed, and we took advantage of this. We have discovered a method of forming an antireflection layer with a two-layer structure of a high refractive index dielectric layer made of a vertically deposited film and a low refractive index dielectric layer made of an obliquely deposited film from a single dielectric material.

The purpose of this invention is to further improve the productivity and workability of multilayer antireflection films by applying the method according to the prior invention to the above-mentioned winding type vacuum deposition apparatus.

[Means to solve the problem]

In the above-mentioned application, the inventors successively form a vertically deposited film and an obliquely deposited film in the flow direction of the film base material between the deposition roll and the evaporation source of a winding type vacuum deposition apparatus. This invention was completed based on the knowledge that the above object could be successfully achieved by interposing a specific anti-adhesion plate for the purpose.

That is, the present invention uses a winding type vacuum evaporation apparatus that performs vacuum evaporation of an evaporation source on the film base material flowing along the surface of the evaporation roll to form a high refractive index dielectric layer on the film base material. In forming an antireflection layer with a 2N composition of a low refractive index dielectric layer and a low refractive index dielectric layer, a through hole for forming a vertically deposited film and a through hole for forming an obliquely deposited film are provided between the vapor deposition roll and the evaporation source. By interposing a deposition-preventing plate having a film, a high refractive index dielectric layer consisting of a vertically deposited film and a low refractive index dielectric layer consisting of an obliquely deposited film can be formed on a film base using a single evaporation source. The present invention relates to a method for producing a multilayer antireflection film, which is characterized in that layers are formed in a continuous manner.

[Structure and operation of the invention]

Hereinafter, a method for producing a multilayer antireflection film of the present invention will be explained with reference to the drawings.

FIG. 1 shows an example of a winding type vacuum evaporation apparatus used in the present invention, in which conduction is established between a supply roll 2 and a take-up roll 3 in a vacuum chamber 1, and four surfaces of the evaporation roll are connected. The evaporation source 6 is vacuum-deposited on the evaporation roll 4 onto the film substrate 5 flowing along the evaporation roll 4, and between the evaporation roll 4 and the evaporation source 6, a transparent film for forming a vertically evaporated film is provided. A deposition prevention plate 7 having holes 7a and through holes 7b for forming an obliquely deposited film is interposed.

Using this apparatus, when vacuum evaporation of the evaporation source 6 onto the film base material 5 is carried out using an appropriate heating means while the film base material 5 is running at a constant speed, first of all, the through holes of the deposition prevention plate 7 are A vertical vapor deposition film is formed on the vapor deposition roll 4 at a portion 4A through the vapor deposition roll 7a, and then the vapor deposition roll 4 is formed on the vertical vapor deposition film through the through hole 7b of the deposition prevention plate 7 as it runs. 4 above
A more oblique vapor deposition film is formed in the B portion.

Here, if a dielectric material with a high refractive index is selected as the evaporation source 6, as shown in FIG. This layer and the second layer consisting of the low refractive index dielectric layer 60B, which is an obliquely deposited film, are successively laminated in this order. That is, according to this method, using one dielectric material, both the above-mentioned layers 60A and 6 are placed on the film base material 5.
A multilayer antireflection film having a two-layer antireflection layer 60 made of 0B can be formed with good productivity and workability.

In this invention, a transparent plastic film is used as the film base material 5, and specifically, polyester, polyvinyl chloride, polystyrene, polyethylene, polycarbonate, polyacrylic resin, polypropylene, polyamide, polyphenylene sulfide, etc. Films include: It is desirable that the thickness of these films is usually in the range of about 10 to 200 μm.

In addition to ZrO□, the evaporation source 6 contains ZrO□ and AI□03.
A high refractive index dielectric material such as a mixture of Y z Os and T 10 z is used. The first dielectric layer 60A made of a vertically deposited film formed from this material has a refractive index in the range of 1.8 to 2.1, and the second dielectric layer 60B made of an obliquely deposited film has a refractive index in the range of 1.8 to 2.1. , its refractive index power month, 4~
It is preferable that it be in the range of 1.6.

It is desirable that the difference in refractive index between both layers is at least 0.4 or more. The thickness of each of the first layer and the second layer is appropriately set to an optical thickness that can effectively prevent reflection of external light, but is generally set in a range of about 800 to 1,500. It is better.

The material of the deposition prevention plate 7 is the part 4A on the deposition roll 4 and the
Any material can be used as long as it prevents vapor deposition in parts other than part B, and aluminum, stainless steel, etc. are generally used. The size and spacing of the through holes 7a and 7b should be determined by taking into account the amount of vapor deposition in the above-mentioned portions 4A and 4B, and determining the film thickness of each layer to an optical film thickness that can effectively prevent the reflection of external light. It should be designed to be.

〔Effect of the invention〕

As described above, in this invention, a high refractive index dielectric layer consisting of a vertically deposited film and a low refractive index dielectric layer consisting of an obliquely deposited film are formed using a single dielectric material using a winding type vacuum evaporation apparatus. Since a two-layer antireflection layer can be formed continuously, the productivity and workability of the multilayer antireflection film can be significantly improved.

〔Example〕

Next, examples of the present invention will be described and explained more specifically.

Example 1 In the roll-up vacuum evaporation apparatus shown in FIG.
A vapor deposition roll 4 and an evaporation source 6 arranged at a distance of cm
At a position 50 cm above the evaporation source 6, a through hole 7a for forming a vertically deposited film having a horizontal length of 5 C1l in a vertical section and a through hole 7b for forming an obliquely deposited film having the same horizontal length of 7 cm are provided between the and both holes 7a.

An aluminum adhesion prevention plate 7 having a horizontal length of 50ffi between the plate and the plate 7b was installed.

Using this vapor deposition apparatus, the degree of vacuum in the vacuum chamber 1 is increased to 2.
X10-'Torr or more, a polyethylene terephthalate film with a thickness of 100 μm was used as the film base material 5, ZrO2 was used as the evaporation source 6, and the winding speed was 7.
Vacuum deposition was performed at 0 cm/min to form a film base material 5.
A first layer 60A having a refractive index of 2.05 is formed by vertically deposited film having a thickness of 1,250 mm, and a second layer 60B having a refractive index of 1.48 is formed by obliquely depositing a film having a thickness of 860 mm. A multilayer antireflection film having the structure shown in FIG. 2 having an antireflection layer 60 consisting of the following was continuously produced.

The multilayer antireflection film produced in this way has an average reflectance of 0 for incident light (wavelength 400 to 700 nm).
．． It was as small as 8% and had very good reflection characteristics.

Example 2 The deposition prevention plate 7 has a through hole 7a for forming a vertically deposited film with a horizontal length of 8 cm in a vertical section and a through hole 7b for forming an obliquely deposited film with a horizontal length of 15 cm, and has both of the above. Except that an aluminum one with a horizontal length of 5 cm between the holes 7a and 7b was used, TiO was used as the evaporation source 6, and the winding speed was changed to 15 cm/min. Vacuum deposition was performed in the same manner as in Example 1.

As a result, a first layer 60A having a refractive index of 2.3 consisting of a vertically deposited film having a thickness of 1,100 mm and a refractive index layer 60A having a refractive index of 2.3 consisting of a vertically deposited film having a thickness of 850 mm on the film base material 5; A multilayer antireflection film having the structure shown in FIG. 2 having an antireflection layer 60 consisting of a second layer 60B of 5.0 and a second layer 60B of 5.0 was successfully produced.

The multilayer antireflection film obtained in this manner was coated with incident light (wavelength: 400 to 700 nm) in the same manner as in Example 1.
), the average reflectance was as low as 0.9%, and it had good reflection characteristics.

[Brief explanation of drawings]

FIG. 1 is a schematic view showing an example of a winding vacuum evaporation apparatus used in the method of the present invention, and FIG. 2 is a sectional view showing an example of a multilayer antireflection film obtained by the method of the present invention. 4... Vapor deposition roll, 5... Film base material, 6...
Evaporation source, 7... Deposition prevention plate, 7a... Through hole for vertical film formation, 7b... Through hole for oblique vapor deposition film formation, 0... Antireflection layer, OA... High refractive index index dielectric layer, 60B...low refractive index dielectric layer

Claims (1)

[Claims] (1) A high refractive index dielectric layer and a low refractive index dielectric layer are deposited on the film base material using a winding type vacuum evaporation device that performs vacuum evaporation of an evaporation source on the roll onto the film base material flowing along the surface of the evaporation roll. In forming an antireflection layer having a two-layer structure with a constant dielectric layer, a through hole for forming a vertically deposited film and a through hole for forming an obliquely deposited film are provided between the vapor deposition roll and the evaporation source. By interposing an anti-deposition plate, a high refractive index dielectric layer consisting of a vertically deposited film and a low refractive index dielectric layer consisting of an obliquely deposited film are successively deposited on a film substrate using a single evaporation source in this order. A method for producing a multilayer antireflection film, which is characterized in that it is formed by laminating layers.