JP2000336196A - Production of laminate film, and reflection-preventing film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a laminate film by which the film useful as a reflection-preventing film can be produced at a temperature hardly causing the degradation or the like of a polymer film, at a high speed by forming a titanium oxide film on the polymer film at a regulated specific temperature by using a specified plasma CVD device. SOLUTION: One or more layers of titanium oxide is formed on a polymer film at a regulated temperature of (-10)-150 deg.C by a plasma CVD device capable of controlling the temperature of the polymer film to provide the objective film. The device preferably has at least a reaction chamber 4 into which a raw material gas is introduced (from a raw material gas-introducing opening 6), a temperature-controllable drum 8 for film-formation, and a plasma- generating means (with an electrode 9 and an electric source 10) for generating plasma 11 between the means and the drum 8. The web-like polymer film 1 is continuously conveyed to the reaction chamber 4 by the drum 8, and the titanium oxide film is formed on the film 1 under the control of the temperature of the film 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a laminated film for forming a titanium oxide film or the like on a polymer film by a plasma CVD method, and an antireflection film obtained by the method.

[0002]

2. Description of the Related Art Computers such as liquid crystal displays, plasma displays and CRTs, word processors, televisions,
BACKGROUND ART Transparent substrates such as glass and plastic are used for various displays used for display panels, display bodies such as instruments, rearview mirrors, goggles, and window glasses.
In addition, since characters, figures, and other information are read through the transparent base material, there is a disadvantage that when the light is reflected on the surface of the transparent base material, the information becomes difficult to read.

[0003] Therefore, an antireflection function is imparted to a substrate. As a method for imparting an antireflection function, for example, silicon oxide (hereinafter, sometimes referred to as “silica”), zirconium oxide, titanium oxide, magnesium fluoride, etc., may be directly applied to a transparent substrate by various methods. There is a method of forming an antireflection film made of an inorganic compound. In particular, since titanium oxide has a high refractive index, it is suitably used for the high refractive index layer of the antireflection film. However, when an anti-reflection film layer containing titanium oxide or the like is directly formed on a transparent substrate, there are many restrictions on the size, thickness, and shape (surface is a curved surface, etc.) of the transparent substrate that can be formed.

[0004] Therefore, a method in which an antireflection film made of a titanium oxide film or the like is formed on a transparent polymer film, and the polymer film formed with the antireflection film is bonded to a substrate required to have an antireflection function. Has been proposed. According to this method, it is possible to greatly reduce restrictions due to the shape of the transparent base material, and it is also possible to reduce the cost for providing an antireflection function to the surface of the transparent base material.

Means for forming an antireflection film such as a titanium oxide film include a vacuum deposition method, a sputtering method, a thermal CVD method, and a wet coating method such as a sol-gel method. However, when trying to form a titanium oxide film on a polymer film by these methods, the following problems occur.

[0006] The vacuum deposition method using titanium or titanium oxide as a raw material has poor adhesion to a substrate. In addition, the sputtering method using titanium or titanium oxide as a target causes a problem that the generation rate of a titanium oxide film is extremely low.

Next, in thermal CVD, the substrate must be heated to a high temperature because of the method of oxidizing and decomposing the raw material gas by the thermal energy of the substrate to form a thin film. For example, when a titanium oxide film is formed by a thermal CVD method, a substrate temperature of about 300 to 500 ° C. is required. When such a high temperature is applied to the polymer film substrate, the polymer compound is decomposed and oxidized, so that it is impossible to form a titanium oxide film on the polymer film by a thermal CVD method.

When a titanium oxide film is formed by wet coating using a sol-gel method or the like, it is difficult to reduce the thickness of the titanium oxide film, make the film quality uniform, and control the film thickness. When a titanium oxide film is used as an anti-reflection layer, the design intended unless a uniform thin film having a thickness of several tens of nm to several hundreds of nm was formed at a specified thickness without variation in the in-plane thickness. The optical function cannot be exhibited. However, when a titanium oxide film for an antireflection layer is formed by a wet wet coating technique such as a sol-gel method, it is difficult to satisfy such strict requirements.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is intended for forming a titanium oxide film or the like for an antireflection layer on a polymer film substrate. Film formation is possible at a temperature at which decomposition, elongation and deformation of the polymer film do not occur, and the film formation speed is high.
An object of the present invention is to provide a method for producing a laminated film having optical performance that can be used as an antireflection film, and an antireflection film obtained by the method.

[0010]

According to the present invention, in order to achieve the above object, a plasma CVD apparatus capable of controlling the temperature of a polymer film is used, and
Provided is a method for producing a laminated film, wherein at least one layer of a titanium oxide film is formed on a polymer film controlled at a temperature within the range of 0 ° C.

By using a plasma CVD method when forming a titanium oxide film on a polymer film, the surface temperature of the film can be maintained at -10 to 150 ° C., so that decomposition, elongation, It is possible to easily form a titanium oxide film without deformation. Here, the plasma CVD method means that atomic or molecular radical species are generated by generating plasma in a reaction chamber into which a predetermined gas is introduced, and adhere to a solid surface. In many cases, volatile molecules are further generated by a surface reaction. This is a film formation method utilizing the phenomenon of being released and taken into the solid surface.

In the first aspect of the present invention, as described in the second aspect, at least a polymer film controlled at a temperature within a range of -10 to 150 ° C. by using the plasma CVD apparatus. A single-layer silica film may be formed.

According to the first or second aspect of the present invention, as set forth in the third aspect, the plasma CVD apparatus includes a reaction chamber into which at least a source gas is introduced, and a film forming apparatus capable of controlling a temperature. Generating means for generating plasma between the film forming drum and the film forming drum, and the web-shaped polymer film is transported by the film forming drum into a reaction chamber into which a source gas is continuously introduced. It is preferable that the apparatus be capable of controlling the temperature of the polymer film and simultaneously forming a film on the polymer film.

By using such an apparatus, it is possible to continuously form a titanium oxide film or a composite film of a titanium oxide film and a silica film on a web-like polymer film, especially a long film. Become. The film is transported by a film forming drum, and the titanium oxide film or the like is formed on the film forming drum. Therefore, by controlling the temperature of the film forming drum, the temperature of the polymer film can be controlled, and the film can be formed in a low temperature state where the film does not deform.
Here, examples of the plasma generating means include an electrode, a coil, an antenna, and a window for introducing an electromagnetic wave, which are connected to a power supply.

According to a third aspect of the present invention, there is provided a plasma CVD apparatus in which a plurality of the reaction chambers are arranged along the outer periphery of the film forming drum. There may be. If a plurality of reaction chambers are arranged, for example, by introducing a raw material gas serving as a raw material of a titanium oxide film and a raw material gas serving as a raw material of a silica film into separate reaction chambers, This is because there is an advantage that a titanium oxide film and a silica film can be manufactured. Also, a plurality of film forming drums may be arranged.

According to the present invention, at least one titanium oxide film having a refractive index of 2.0 or more and 2.9 or less (wavelength λ = 550 nm) is formed on a polymer film by a plasma CVD method. The present invention provides an antireflection film characterized by being laminated by:

Since the titanium oxide film laminated on the polymer film is formed by the plasma CVD method, the titanium oxide film has a necessary refractive index and has high quality without deterioration of the polymer film. It can be set as an anti-reflection film. Further, as the optical characteristics required for the titanium oxide film, the refractive index is 2.0 or more (wavelength λ = 550 n).
m) is required. This is because, if the refractive index is less than 2.0, the titanium oxide film itself is incompletely formed, which is lower than the standard required as a product of the antireflection film. Further, since the refractive index of the titanium oxide film cannot usually be 2.9 or more (wavelength λ = 550 nm), the upper limit of the refractive index of the titanium oxide film in the present invention is 2.9.
It was set to 9.

According to the fifth aspect of the present invention, as described in the sixth aspect, the polymer film is laminated on the polymer film by a plasma CVD method on the surface of the polymer film on which the titanium oxide film is formed. An antireflection film having a formed silica film may be used.

In the invention described in claim 6, as described in claim 7, the outermost layer is preferably the silica film. This is because the silica film has a lower refractive index and a lower reflectance than the titanium oxide film, and therefore has a large antireflection effect when used as the outermost layer of the antireflection film. Further, since the silica film has relatively small surface energy, it has antifouling property and water repellency. Therefore,
This is because the antireflection film can also be provided with antifouling properties and water repellency.

In the antireflection film according to any one of claims 5 to 7, as described in claim 8, a hard coat layer is formed on the polymer film. It is preferably an antireflection film in which a film formed by the plasma CVD method is laminated on the hard coat layer. By providing the hard coat layer in this manner, the antireflection film can have scratch resistance.

Further, in the invention described in claim 8, as described in claim 9, it is preferable that a medium refractive index layer is formed on the hard coat layer. This is because the formation of the middle refractive index layer can improve the antireflection effect.

In the invention according to any one of claims 5 to 9, as described in claim 10, the polymer film is a uniaxially or biaxially stretched polyester film, or triacetyl. Preferably, it is a cellulose film. Polyester film is excellent in transparency and heat resistance, so it can be used as an antireflection film in various applications, and triacetyl cellulose film is similar to polyester film in that it has no optical anisotropy. This is because it is suitable for an antireflection film.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The method for producing a laminated film of the present invention uses a plasma CVD apparatus capable of controlling the temperature of a polymer film,
The method is characterized in that at least a titanium oxide film is formed on a polymer film controlled at a temperature within a range of -10 to 150 ° C.

The plasma CVD apparatus used in the present invention is not particularly limited as long as it can control the temperature of the polymer film, and there is no particular limitation on the power supply frequency or the plasma generation method. A method for manufacturing a laminated film in which a titanium oxide film is formed on a polymer film using such a plasma CVD apparatus will be described with reference to FIG.

First, a web-like polymer film 1 is unwound from a substrate unwinding section 2 and is introduced into a plasma CVD reaction chamber 4 in a vacuum vessel 3. The whole reaction vessel 3 is evacuated by a vacuum pump 5. At the same time, a predetermined flow rate of an organic titanium compound gas and an oxygen gas are supplied from the raw material gas inlet 6 to the reaction chamber 4, and the inside of the reaction chamber 4 is always filled with these gases at a constant pressure.

Next, it is unwound from the base material unwinding unit 2,
The polymer film 1 introduced into the reaction chamber 4 is wound around a film forming drum 8 via a reversing roll 7,
The sheet is fed in the direction of the reversing roll 7 'in synchronization with the rotation of. At this time, the temperature of the film forming drum 8 can be controlled, and at this time, the surface temperature of the polymer film 1 and the surface temperature of the film forming drum 8 are substantially equal. Therefore, the surface temperature of the polymer film 1 on which titanium oxide is deposited during plasma CVD, that is, the film forming temperature of plasma CVD can be arbitrarily controlled. In this example, the plasma CV
The film forming temperature when the titanium oxide film 12 is formed on the polymer film 1 by D is indicated by the surface temperature of the film forming drum 8 at that time.

An RF voltage is applied between the electrode 9 and the film forming drum 8 by a power supply 10. At this time, the frequency of the power supply is not limited to the radio wave, and an appropriate frequency from DC to microwave can be used. Then, by applying an RF voltage between the electrode 9 and the film forming drum 8, a plasma 11 is generated around the two electrodes. Then, the organic titanium compound gas and the oxygen gas react in the plasma 11 to generate titanium oxide and deposit it on the polymer film 1 wrapped around the film forming drum 8 to form a titanium oxide film 12. . After that, the polymer film 1 having the titanium oxide film 12 formed on the surface thereof is wound by the base material winding unit 2 'via the reversing roll 7'.

As described above, in the present invention, the titanium oxide produced by the chemical reaction of the organic titanium compound gas and the oxygen gas by the plasma 11 is cooled by the film forming drum 8 to an appropriate temperature. Deposited on 1
Since the titanium oxide film is formed, the polymer film 1 is exposed to a high temperature, and the titanium oxide film 12 can be formed without stretching, deforming, curling, or the like. Further, in the plasma CVD method of the present invention, the refractive index, the film thickness, etc. of the titanium oxide film 12 to be formed are controlled in a wide range by controlling the flow rate and pressure of the material gas, the discharge conditions, and the speed of feeding the polymer film 1. Therefore, a film having desired optical characteristics can be obtained without changing the material.

The materials and conditions used in the present invention will be described below in more detail.

Materials that can be used as the organic titanium compound of the present invention include Ti (i-OC ₃ H ₇ ) ₄ (titanium tetra i-propoxide), Ti (OCH ₃ ) ₄ (titanium tetramethoxide), Ti (OC ₂ H ₅ ) ₄ (titanium tetraethoxide), Ti (n-OC ₃ H ₇ ) ₄ (titanium tetra n
- _{propoxide), Ti (n-OC 4} H 9) 4 ( titanium tetra n- butoxide), and titanium alkoxide _{Ti (t-OC 4 H 9} ) 4 ( titanium tetra t- butoxide). Its Do _{But, Ti (i-OC 3 H} 7) 4 ( titanium tetra i- _{propoxide), Ti (t-OC 4} H 9)
₄ (titanium tetra-t-butoxide) is preferred because of its high vapor pressure.

These organic titanium compounds are evaporated in a liquid vaporizer and introduced into the reaction chamber in the form of an organic titanium compound gas. Oxygen gas is also introduced into the reaction chamber. This oxygen gas has a role as a reaction gas for producing titanium oxide by reacting with the organic titanium compound gas. In some cases, a rare gas is used as a carrier gas for the organic titanium compound gas. It is desirable that the flow ratio of the oxygen gas and the organic titanium compound gas (oxygen gas / organic titanium compound gas) be 5 or more. If it is smaller than this range, the amount of carbon mixed into the film increases, and the refractive index of the formed titanium oxide film decreases. A suitable pressure in the reaction chamber is 1 Torr or less. If the pressure is higher than 1 Torr, there is a problem that the refractive index and mechanical strength of the formed titanium oxide film decrease. The partial pressure of the organic titanium compound gas is preferably 10 ^-1 Torr or less. Partial pressure of organic titanium compound gas is 10 ^-1 T
When it is larger than orr, there is a problem that the organic titanium compound is liquefied in the reaction chamber.

The polymer film that can be used in the present invention needs to be transparent. Examples thereof include a triacetyl cellulose film, a diacetyl cellulose film, an acetate butyrate cellulose film, a polyether sulfone film, and a polyacrylic film. , A polyurethane film, a polyester film, a polycarbonate film, a polysulfone film, a polyether film, a trimethylpentene film, a polyetherketone film, an acrylonitrile film, and a methacrylonitrile film. Further, a colorless and transparent film can be more preferably used. Above all, a uniaxially or biaxially stretched polyester film is excellent in transparency and heat resistance and is preferably used, and triacetyl cellulose is also suitably used in that it has no optical anisotropy. Usually, the thickness of the polymer film is preferably about 6 μm to 188 μm.

In the present invention, since the temperature of the film forming drum can be controlled, the surface temperature of the polymer film on which titanium oxide is deposited during plasma CVD, that is, the film forming temperature of plasma CVD can be arbitrarily controlled.
This film formation temperature is set at a temperature of -10 to 150 ° C. If the temperature is lower than −10 ° C., the refractive index of the formed titanium oxide film decreases, which is not preferable. Further, when the film formation temperature exceeds 150 ° C., it causes problems such as elongation, deformation, and curl during film formation because the temperature becomes higher than the thermal deformation temperature of the polymer film of the substrate usable in the present invention. Absent.

Further, when the antireflection film is required to have a high quality that does not allow slight undulation, deformation and elongation, or when the base polymer film is thinner than 10 μm and easily susceptible to elongation deformation due to heat,- Plasma CVD of titanium oxide film at a temperature of 10 ° C. to Tg of polymer film or less
It is particularly desirable to form a film.

In the example shown in FIG. 1, the temperature of the polymer film is controlled by bringing the polymer film into close contact with the film forming drum and controlling the temperature of the film forming drum. The method is not limited to this, and any method that can control the temperature of the polymer film when the film is formed by plasma CVD can be used, for example, by controlling the temperature of the atmosphere in the reaction chamber. There is no particular limitation on the method of controlling, the method of setting the polymer film to a predetermined temperature in advance, and then feeding the polymer film into the reaction chamber.

Using a plasma CVD apparatus, -10 to 15
The method of forming a silica film in addition to a titanium oxide film on a polymer film controlled within the range of 0 ° C. is the same as that of the titanium oxide film.

In the present invention, raw materials for forming a silica film include silane, disilane, hexamethyldisiloxane (HMDSO), and tetramethyldisiloxane (T
MDSO), methyltrimethoxysilane (MTMO)
S), Si-based compounds such as methylsilane, dimethylsilane, trimethylsilane, diethylsilane, propylsilane, phenylsilane, tetramethoxysilane, octamethylcyclotetrasiloxane, and tetraethoxysilane can be used.

In addition, for the preparation of titanium oxide and silica films,
It is also possible to use a plasma CVD apparatus as shown in FIG. The plasma CVD apparatus is a capacitively coupled plasma CVD apparatus, the basic structure and principle of which are shown in FIG.
It is the same as the device of the above. Therefore, also in this apparatus, the web-like polymer film 21 is unwound from the base material unwinding part 22 and is reacted in the reaction chamber (a, b, c) in the vacuum vessel 23.
Will be introduced. Then, the film forming drum 2 in the reaction chamber
A predetermined film is formed on 4, and is wound by the base material winding unit 26.

The difference between the apparatus shown in FIG. 2 and the apparatus shown in FIG. 1 is that, in the apparatus shown in FIG. 1, only one reaction chamber for forming a titanium oxide film on a film is provided. A plurality (three) of the plasma CVD apparatuses shown in FIG.
In the reaction chamber. Each reaction chamber (a,
b, c) are formed by being isolated by the isolation wall 25. Here, for convenience of the following description, the three reaction chambers are referred to as a reaction chamber a, a reaction chamber b, and a reaction chamber c from the right side. Each of the reaction chambers is provided with an electrode plate a1, b1, c1 and a source gas inlet a2, b2, c2.

Each reaction chamber (a, b, c) is set along the outer periphery of the film forming drum 24. This is because the polymer film on which the laminated film is formed is inserted into the reaction chamber in synchronization with the film forming drum 24 as described in the example shown in FIG. 1, and the laminated film is formed on the film forming drum. This is because, by arranging in this manner, the respective films can be successively laminated. Although the number of reaction chambers is three in the apparatus shown in FIG. 2, the plasma CVD apparatus used in the method for producing a laminated film of the present invention is not limited to this, and may be changed as necessary. Can be.

According to the plasma CVD apparatus as described above, it is possible to form a film independently in each reaction chamber by changing the source gas introduced into each reaction chamber. When a laminated film of a titanium oxide film and a silica film is formed on a polymer film, the reaction chamber a
A gas containing an organic titanium compound is introduced into the reaction chamber b, and a gas containing silicon is introduced into the reaction chamber b and the reaction chamber c, whereby the polymer film 21 is wound around the substrate winding section 26 via the film forming drum 25. The polymer film 21 before being removed
It is possible to form a laminated film on which a titanium oxide film and a silica film are formed.

Further, in the above case, the gas introduced into the reaction chamber b and the reaction chamber c is a gas containing silicon, but the conditions in each reaction chamber, for example, the gas flow rate and pressure,
By changing the discharge conditions and the like, it is also possible to change the characteristics of the silica film formed in the reaction chamber b and the reaction chamber c. The titanium oxide film, the silica film, and the thickness and the refractive index of these films can be freely combined by the device.

It is not always necessary to introduce different source gases into the respective reaction chambers. For example, by introducing a gas containing an organic titanium compound into all of the reaction chambers a, b and c shown in FIG. After that, all gases once introduced into the reaction chambers a, b, and c are removed, and a gas containing silicon is introduced again into the reaction chambers a, b, and c to form a silica film on the titanium oxide film. It is also possible.

In the present invention, a polymer film is treated a plurality of times with the apparatus shown in FIG. 1 to form a laminated film in which a titanium oxide film and a silica film are formed on the polymer film. You can do it,
As described above, by processing the polymer film at one time using the apparatus shown in FIG. 2, a laminated film in which a titanium oxide film and a silica film are formed on the polymer film may be formed. . Further, by treating the polymer film a plurality of times using the apparatus shown in FIG. 2, it is possible to obtain a laminated film in which a plurality of titanium oxide films and a plurality of silica films are alternately laminated.

Next, the antireflection film of the present invention will be described.

The antireflection film of the present invention is characterized by having at least one layer of a titanium oxide film having a refractive index of 2.0 to 2.9 formed on a polymer film by a plasma CVD method. is there. Such an antireflection film can be used at a temperature of -10 to 150 ° C.
By laminating a titanium oxide film on a polymer film within the above temperature range, a high-quality antireflection film without degradation of the polymer film can be obtained.

Hereinafter, the antireflection film of the present invention will be specifically described with reference to the drawings. FIG. 3 shows an example of the antireflection film of the present invention. The antireflection film shown in this example uses a polyethylene terephthalate (PET) film as a polymer film, and a hard coat layer, a medium refractive index layer, a titanium oxide film, and a silica film as a low refractive index layer are formed on the PET film. These are sequentially laminated.

The antireflection film of the present invention is obtained by laminating at least one layer of a titanium oxide film and a silica film on a polymer film.

The formation position of the silica film is not particularly limited. The silica film may be formed on the upper layer or the lower layer of the titanium oxide film, but may be formed on the outermost layer. It is preferable to have a layer structure. This is because the silica film has a lower refractive index and a lower reflectance than the titanium oxide film, and therefore has a large antireflection effect when used as the outermost layer of the antireflection film. Further, since the silica film has relatively small surface energy, it has antifouling property and water repellency. Therefore, the antireflection film can be imparted with antifouling properties and water repellency.

In the anti-reflection film of the present invention, the titanium oxide film and the silica film may be laminated one by one as shown in FIG. 3, for example. For example, as shown in FIG. 4, a titanium oxide film and a silica film may be formed in a plurality of layers such as a two-layer polymer film. This is because such a configuration improves the anti-reflection effect.

In the present invention, a hard coat layer may be provided on the polymer film as shown in the examples of FIGS. This is because the provision of the hard coat layer can increase the mechanical strength of the antireflection film. It is preferable that the hard coat layer is formed on the polymer film as a layer below the layer formed by the plasma CVD method such as a titanium oxide film.

Further, in the antireflection film of the present invention, a middle refractive index layer may be formed as required, for example, as shown in FIG. This medium refractive index layer has a refractive index intermediate between the refractive index of the polymer film and the refractive index of the titanium oxide film formed by the plasma CVD method. By providing between the film and the polymer film, the antireflection effect can be further improved.

Next, each layer constituting the antireflection film of the present invention will be described.

(Titanium Oxide Film) The titanium oxide film of the present invention is laminated on a polymer film by a plasma CVD method and has a refractive index of 2.0 to 2.9 (wavelength λ = 55).
0 nm) is not particularly limited.

Here, the refractive index of the titanium oxide film is preferably from 2.0 to 2.5 (λ = 550 nm), particularly preferably from 2.0 to 2.3 (λ = 550 nm), within the above range. When forming an anti-reflection film, it is preferable that the refractive index of the titanium oxide film is relatively determined in relation to other laminated films, and the anti-reflection effect is exhibited by the balance of the entire laminated film. However, the refractive index of the titanium oxide film in the case of a general laminated structure is preferably in the above range.

In the present invention, an antireflection film in which the temperature of the polymer film is controlled at -10 to 150 ° C. and a titanium oxide film is laminated is particularly preferable. The titanium oxide film thus laminated is excellent in film thickness distribution without elongation or deformation of the substrate, and is suitable as an antireflection film.

In the present invention, at least the reaction chamber into which the raw material gas is introduced is temperature-controllable because it can be manufactured continuously and the temperature of the polymer film can be accurately controlled. Film forming drum,
A plasma generating means for generating plasma between the film-forming drum and the film-forming drum, whereby a web-like polymer film is continuously transferred into a reaction chamber into which a source gas is introduced; A plasma CVD apparatus in which a temperature is controlled on the polymer film and a film is formed on the polymer film at the same time, specifically, a titanium oxide film formed by the plasma CVD apparatus as shown in FIG. It is preferable that the antireflection film has

The optical properties required for the titanium oxide layer in the antireflection film are required to be such that the refractive index of the titanium oxide film is 2.0 or more. Even if the substrate has elongation or deformation, the base material often becomes defective if it is stretched or deformed. Therefore, in order to prevent the deformation of the base material due to the heating and the inhibition of the formation of the titanium oxide film due to the deformation, it is preferable to control the film formation temperature as described above.

(Low Refractive Index Layer) The low refractive index layer in the present invention is formed on a polymer film together with the titanium oxide film as described above, thereby improving the antireflection effect of the antireflection film. Among the low refractive index layers, those in which a silica film is formed by a plasma CVD method are preferable, and the temperature of the polymer film is particularly preferably −10.
An antireflection film in which silica is laminated at a temperature controlled to 150 ° C. is preferable. The silica film thus laminated has an excellent thickness distribution and is suitable as an antireflection film. Further, the refractive index of the low refractive index layer is 1.3 to 1.3.
1.5 is preferable, and for example, magnesium fluoride or silicon oxyfluoride may be used in addition to the silica film. Regarding the optical properties, magnesium fluoride and silicon oxyfluoride are more excellent in physical properties required for the low refractive index material than the silica film. However, since magnesium fluoride and the like are inferior in mechanical strength and moisture resistance to silica films, depending on the use, it is preferable to use together with a means such as laminating a strength layer or a barrier layer. In that respect, the silica film is most suitable comprehensively, because no special means is required for the use of the magnesium fluoride or the like.

In the present invention, for the same reason as the above-described titanium oxide film, at least a reaction chamber into which a raw material gas is introduced, a film forming drum capable of controlling the temperature, and a plasma between the film forming drum. Temperature control of the polymer film by, for example, transferring the web-like polymer film into the reaction chamber into which the source gas is introduced by the film forming drum. It is preferable to use an antireflection film having a low refractive layer formed by a plasma CVD apparatus in which a film is formed on the polymer film at the same time as the above.

Among them, a CVD apparatus in which at least two reaction chambers are formed along the outer periphery of a film forming drum, specifically, a low refractive index layer formed by a plasma CVD apparatus as shown in FIG. It is preferable that the antireflection film has A titanium oxide film and a low-refractive-index layer are formed in a single process by introducing a raw material for a titanium oxide film and a raw material for a low-refractive-index layer into the above-described reaction chamber to produce an antireflection film. This is because the formed antireflection film can be formed.

(Polymer Film) The polymer film that can be used for the antireflection film of the present invention is not particularly limited as long as it is a polymer film that is transparent in the visible light region. Specifically, those described in the method for producing a laminated film described above can be used. In the present invention, among others, a uniaxially or biaxially stretched polyester film is preferable because of its excellent transparency and heat resistance, and a polyethylene terephthalate (PET) film is particularly preferable. Also, a triacetyl cellulose film is similarly suitable as an antireflection film in that it has no optical anisotropy.

The thickness of such a polymer film is usually about 6 μm to 188 μm.

(Hard Coat Layer) The heart coat layer used in the present invention is a layer formed for the purpose of imparting strength to the antireflection film of the present invention. Therefore,
It is not always necessary depending on the use of the antireflection film.

The material for forming such a hard coat layer is not particularly limited as long as it is a material which is similarly transparent in the visible light range and can give the antireflection film strength. For example, a UV-curable acrylic hard coat or a thermosetting silicone-based coating can be used.

The thickness of the hard coat layer used in the present invention is usually in the range of 1 to 30 μm. In addition, the method for producing such a hard coat layer may be an ordinary coating method, and is not particularly limited.

(Medium Refractive Index Layer) Medium Refractive Index Layer in the Present Invention
Is a layer used to enhance the anti-reflection function,
It is not always necessary like the above hard coat
No. Such a medium refractive index layer is transparent in the visible light range,
And made of a material having a refractive index in the range of 1.5 to 2.0
The layer is not particularly limited as long as the layer is formed. concrete
As a substance for forming a medium refractive index layer, for example,
Al_TwoO_Three, SiN, SiON, ZrO _Two, SiO_Two, Z
nO_TwoDispersion of organic fine particles in organosilicon compound, etc.
Is preferably used. Also, the middle refractive index layer is not necessarily one layer
It is not necessary to stack several different layers
By setting the layer configuration so that the above-mentioned refractive index is obtained,
The laminated film may be a medium refractive index layer.

The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and has substantially the same configuration as the technical idea described in the scope of the claims of the present invention. It is included in the technical scope of the invention.

[0069]

The present invention will be described in more detail with reference to examples.

Example 1 Using the apparatus shown in FIG. 1, a titanium oxide film was formed on a 100 μm thick polyethylene terephthalate (PET) film which was a polymer film as a base material. As the organic titanium compound gas, titanium tetraisopropoxide Ti (i-OC ₃ H ₇ ) ₄ vaporized at 150 ° C. using a liquid vaporizer is used, mixed with oxygen gas, and supplied to the reaction chamber through a raw material gas inlet. Was introduced. The respective flow rates of the organic titanium compound gas and the oxygen gas are shown below. The plasma CVD device of Fig. 1 used this time is a capacitive coupling type,
A 13.56 MHz RF power supply was used as a high frequency power supply. The feed rate of the polymer film as the substrate during continuous film formation is 10 m / min. Other conditions are described below.

<Film Forming Conditions> Applied power 2 kW Titanium tetraisopropoxide gas flow rate 100 sccm Oxygen gas flow rate 1000 sccm Surface temperature of film forming drum (film forming temperature) 0 ° C.

The gas flow unit sccm is defined as
It is dar cubic cm per minute.

The measurement results of the titanium oxide film formed on the polyethylene terephthalate film under the above conditions are shown below.

<Measurement Results of Titanium Oxide Film> Film thickness 233 nm Film formation rate 2330 nm · m / min Composition Ti: O: C = 27: 53: 20 Refractive index (λ = 550 nm) 2.00 The structure of titanium oxide is amorphous Met.

<Apparatus Used for Titanium Oxide Film Measurement> Film Thickness Measurement Ellipsometer Model No. UVISEL ^™ Maker JOBIN YVON Composition Analysis Photoelectron Spectroscopy Model ESCALAB220i-XL Maker VG Scientific Refractive Index Measurement Ellipsometer Model No. UVISEL ^™ Maker JOBIN YVON X-ray Structure Diffractometer Model RINT 1500 Manufacturer RIKEN ELECTRIC CO., LTD.

As shown above, at a film formation temperature of 0 ° C., a uniform titanium oxide film having a refractive index of 2.00 was formed at a high film formation rate of 2330 nm · m / min. On a polyethylene terephthalate film. Further, as a result of measuring the titanium oxide film with an ellipsometer, the extinction coefficient at λ = 550 nm was 0.001 and there was no problem of coloring. In addition, the polyethylene terephthalate film after the formation of the titanium oxide film was in a good state without slight elongation or deformation.

Example 2 A titanium oxide film was formed under the same conditions as in Example 1 except that the film formation temperature was 80 ° C. Also, the equipment used for measuring the titanium oxide film was
Same as Example 1. The results are described below.

<Results of Measurement of Titanium Oxide Film> Film thickness 210 nm Film formation rate 2100 nm · m / min Composition Ti: O: C = 31: 57: 12 Refractive index (λ = 550 nm) 2.23 The structure of titanium oxide is amorphous Met.

As shown above, a uniform titanium oxide film having a refractive index of 2.23 was formed on a polyethylene terephthalate film at a high deposition rate at a deposition temperature of 80 ° C. . In addition, since the titanium oxide film was formed at a temperature equal to or lower than the Tg (90 ° C.) of the polyethylene terephthalate film, the polyethylene terephthalate film after the film formation was in a favorable state without slight elongation and deformation.

Example 3 A titanium oxide film was formed under the same conditions as in Example 1 except that the film formation temperature was 100 ° C. The apparatus used for measuring the titanium oxide film was the same as in Example 1. The results are described below.

<Measurement Results of Titanium Oxide Film> Film thickness 205 nm Film formation rate 2050 nm · m / min Composition Ti: O: C = 31: 58: 11 Refractive index (λ = 550 nm 2.25) The structure of titanium oxide is amorphous. there were.

As shown above, a uniform titanium oxide film having a refractive index of 2.25 was formed on a polyethylene terephthalate film at a high film forming rate at a film forming temperature of 100 ° C. . After the formation of the titanium oxide film, the polyethylene terephthalate film was usable with little elongation and deformation.

(Comparative Example 1) A titanium oxide film was formed under the same conditions as in Example 1 except that the film formation temperature was -20 ° C. The apparatus used for measuring the titanium oxide film was the same as in Example 1. The results are described below.

<Measurement Results of Titanium Oxide Film> Film thickness 260 nm Film formation rate 2600 nm · m / min Composition Ti: O: C = 23: 49: 27 Refractive index (λ = 550 nm) 1.80 The structure of titanium oxide is amorphous Met.

After forming the titanium oxide film at the film forming temperature of −20 ° C., the polyethylene terephthalate film was stretched and did not deform at all. However, since the refractive index of the titanium oxide film is 1.80, the refractive index of 2.0, which is generally required as a high refractive index layer of the antireflection layer, cannot be obtained, which is unsuitable for use. Was. This is because, if the refractive index is less than 2.0, the formation of the titanium oxide film itself is incomplete,
This is because the standard is lower than a standard required for an antireflection film product.

Comparative Example 2 A titanium oxide film was formed under the same conditions as in Example 1 except that the film formation temperature was 200 ° C. The apparatus used for measuring the titanium oxide film was the same as in Example 1. The results are described below.

<Measurement Results of Titanium Oxide Film> Film thickness 195 nm Film formation rate 1950 nm · m / min Composition Ti: O: C = 34: 61: 5 Refractive index (λ = 550 nm) 2.39 The structure of titanium oxide is amorphous Met.

As shown above, at a film formation temperature of 200 ° C., a titanium oxide film having a refractive index of 2.39 was formed. However, the polyethylene terephthalate film as the base material was significantly elongated and deformed. The result was unsuitable.

The above results are summarized in Table 1.

[0090]

[Table 1]

As shown in Table 1, when the film forming temperature is in the range of -10 to 150 ° C., the refractive index of the titanium oxide film is 2.0 or more, and the refractive index 2 required for the high refractive index layer of the antireflection layer is generally required. 0.0 or more, and the elongation and deformation of the polymer film of the substrate were slight and were at a level without any problem. Further, a sample in which a titanium oxide film is formed at a temperature lower than the Tg (90 ° C.) of polyethylene terephthalate used as a polymer film and at a film formation temperature of −10 ° C. or more has a refractive index of 2.0 or more. It was good, and there was no slight elongation or deformation of the polymer film as the base material, and a particularly suitable sample was obtained.

In the sample formed at a temperature lower than −10 ° C., the formed titanium oxide film has a low refractive index (1.8).
0), which was not suitable as a high refractive index layer of the antireflection film. In the samples formed at a temperature higher than 150 ° C., the polymer film of the base material was significantly stretched and deformed due to heat, so that it could not be used.

Example 4 As shown in FIG. 5, a hard coat layer 31, a medium refractive index layer 32, a high refractive index layer 33, and a low refractive index layer 34 were formed on a polymer film 30, and an antireflection film was formed. Created. The conditions for forming each layer are described below.

<Polymer Film (30)> Polyethylene Terephthalate Film Thickness 100 μm

<Hard coat layer (31)> UV-curable resin PET-D31 (Dainichi Seika Kogyo Co., Ltd.)
Co., Ltd. Formed by coating UV curing conditions 480 mJ Thickness 6 μm

<Medium Refractive Index Layer (32)> ZrO ₂ fine particle coating liquid No. 1221 (ZrO ₂
A coating solution consisting of 0.3 parts by weight of a binder (ionizing radiation-curable organosilicon compound) per 100 parts by weight of fine particles: formed by wire bar coating UV curing conditions 480 mJ Thickness 88 nm

<High refractive index layer (33)> Formed under the same conditions as in Example 2.

<Low Refractive Index Layer (34)> An SiO ₂ layer is formed by a plasma CVD method.

The antireflection film formed under the above conditions is
The polymer film was in a good state without slight elongation or deformation. FIG. 6 shows the reflection spectral characteristics of the antireflection film prepared under the above conditions. FIG. 6 shows that the reflectance near 550 nm, which is easily perceived by humans, was low and the antireflection effect was good. The luminous reflectance at this time showed a good value of 0.7%.

The spectral reflectance was measured by the following device. Spectral reflectance measurement Spectrophotometer Model number UV-3100PC Manufacturer Shimadzu Corporation

Comparative Example 3 An antireflection film was prepared under the same conditions as in Example 4, except that the conditions for forming the high refractive index layer 33 shown in FIG.

The antireflection film formed under the above conditions is
The polymer film was in a good state without slight elongation or deformation. However, as shown in FIG. 7, the reflectance near 550 nm, which is easily perceived by humans, was high, and the antireflection effect was poor. The luminous reflectance at this time is 1.6.
%, Which was unsuitable.

(Embodiment 5) Embodiment 5 uses the apparatus shown in FIG. In Example 5, a 100 μm-thick polyethylene terephthalate (PET) was used in which a hard coat of 6 μm and a middle refractive index layer of 88 μm were sequentially coated. Further, a titanium oxide film was formed in the reaction chamber a shown in FIG. 2, and a silica film was formed in the reaction chambers b and c. A 13.56 MHz RF power supply was used as a high frequency power supply, and the feed rate of the polymer film as the base material during continuous film formation was set at 20 m / min. Other conditions are as shown below.

<Titanium oxide film formation conditions (reaction chamber a)> Applied power 30 kW Pressure 50 mTorr Titanium tetraisopropoxide gas flow rate 1 slm Oxygen gas flow rate 10 slm Film forming drum surface temperature (film formation temperature) −20 ° C.

<Silica film formation conditions (reaction chambers b and c)> Applied power 30 kW Pressure 50 mTorr HMDSO flow rate 1 slm Oxygen gas flow rate 10 slm Film forming drum surface temperature (film forming temperature) −20 ° C.

The above-mentioned gas flow unit slm is represented by
ard liter per minute.

The measurement results of the laminated film formed on the base film under the above conditions are shown below.

<Laminated Film Measurement Results> FIG. 3 shows the layer configuration of the laminated film.
Shown in Further, the luminous reflectance was measured from the reflection spectrum of the laminated film, and was found to be 0.39%. FIG. 8 shows the reflection spectrum.

The base film has a slight elongation,
It was in a good state without any deformation. In addition, when a peel test was performed on each film constituting the laminated film, it was found that all the layers had an adhesion strength of 1 kg / cm or more.

Further, when the substrate film on which the laminated film was formed according to the present example was pasted on an LCD, it was visually confirmed that reflection by illumination or the like was reduced.

(Example 6) As in Example 5, a laminated film was formed using the plasma CVD apparatus shown in FIG. In this example, 100 μm thick polyethylene terephthalate (PET) was used as a substrate. Further, in this embodiment, unlike the above-described embodiment 5, first, three reaction chambers (a,
A titanium oxide film was formed in all of b) and c), and then a silica film was formed in all the reaction chambers. Then, by repeating this process twice, the titanium oxide film-silica film-
A laminated film of a titanium oxide film and a silica film was formed.

The conditions for forming the titanium oxide film and the silica film were the same as those in the fifth embodiment.

<Laminated Film Measurement Results> The layer structure of the laminated film is shown in FIG.
Shown in Here, the thickness of each film is adjusted by the feed speed of the base film. When the luminous reflectance was measured from the reflection spectrum of the laminated film shown in FIG.
35% was obtained. FIG. 9 shows the reflection spectrum of the laminated film. The base film was in a good state without any elongation or deformation.

Further, when a peel test was performed on each film constituting the laminated film, it was found that all the layers had an adhesion strength of 1 kg / cm or more.

Further, when the substrate film on which the laminated film was formed according to the present example was pasted on an LCD, it was visually confirmed that the reflection due to illumination or the like was reduced, and the same result as in Example 5 was obtained. Obtained.

(Comparative Example 4) An antireflection film having the same layer structure as in Example 5 (see FIG. 3) was formed by a thermal CVD method. The same raw materials as in Example 5 were used for forming the film, and the temperature of the film forming chamber was 400 ° C.

However, the base film was deformed by heat, and it was impossible to produce an antireflection film.

Comparative Example 5 Next, an antireflection film having the same layer structure as that of Example 5 (see FIG. 3) was produced by a sputtering method. The deposition rate is about 5 for the titanium oxide film.
0 nm / min, about 100 nm / m
went in.

FIG. 10 shows the layer structure formed by the sputtering method, and FIG. 11 shows its reflection spectrum.

A comparison between FIG. 10 and FIG. 3 shows that it is possible to form a layer configuration substantially similar to that of the embodiment of the present invention by the sputtering method. However, FIG.
When the luminous reflectance was measured from the reflection spectrum shown in FIG. 1, it was found that Example 5 of the present invention was 0.39, whereas that formed by the sputtering method was 0.41. Further, when a peak test was performed on each layer, the layer formed by Example 5 of the present invention had an adhesion strength of 1 kg / cm or more, whereas the layer formed by the sputtering method had an adhesion strength of about 550 g / cm. It was a low value.

Therefore, in the sputtering method, it is possible to produce an antireflection film having substantially the same layer constitution as that of the embodiment of the present invention, but the performance as an antireflection film is different from that of the antireflection film of the present invention. It turned out to be inferior.

Comparative Example 6 Further, an antireflection film having the same layer structure as that of Example 5 (see FIG. 3) was produced by a vacuum deposition method. At this time, Ti ₂ O ₃ and SiO ₂ were used as raw materials. The film formation rate is about 100 nm / min for the titanium oxide film and about 200 n for the silica film.
m / min.

FIG. 12 shows the layer structure formed by the vacuum evaporation method, and FIG. 13 shows the reflection spectrum.

FIG. 12 shows that in the vacuum deposition method, as in the case of the above-described sputtering method, the layer structure is the same as that of the fifth embodiment of the present invention.
It can be seen that it is possible to form the same layer configuration as in FIG. However, when the luminous reflectance was measured from the reflection spectrum shown in FIG.
On the other hand, those formed by the vacuum evaporation method have a diameter of 0.1 mm.
It turned out to be 41. Further, when the peak test of each layer was performed, it was found that the layer formed in Example 5 of the present invention was 1 layer.
While the layer had an adhesion strength of at least kg / cm, the layer formed by the vacuum evaporation method had a low value of about 200 g / cm.

Thus, in the vacuum deposition method, it is possible to produce an antireflection film having substantially the same layer structure as that of the fifth embodiment of the present invention. Was inferior to the antireflection film of the present invention.

As is clear from the above examples and comparative examples, in the examples of the present invention, there was no elongation or deformation of the polymer film as the base material, and the high refractive index layer had a high refractive index. , An antireflection film having a high antireflection effect can be obtained.

The thicknesses of the laminated films formed in the above Examples and Comparative Examples were set so that the luminous reflectance was minimized in consideration of the optical characteristics of each layer. For example, in the high refractive index layer and the low refractive index layer shown in Example 4, a desired film thickness is obtained by adjusting the film feeding speed when forming each layer using the apparatus shown in FIG.

[0128]

According to the present invention, when a titanium oxide film, a silica film, etc. are formed on a polymer film, the surface temperature of the film can be maintained at -10 to 150 ° C. by using the plasma CVD method. A titanium oxide film can be formed without causing decomposition, elongation, and deformation of the film. In addition, since the silica film has a lower refractive index and a lower reflectance than the titanium oxide film, the antireflection effect increases when used as the outermost layer of the antireflection film, and the silica film has a relatively small surface energy. Therefore, it has antifouling property and water repellency. Therefore, the antireflection film can also be provided with antifouling properties and water repellency. Thus, the film formed according to the present invention is suitable for use as an antireflection film.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a manufacturing method of the present invention.

FIG. 2 is a schematic diagram for explaining the manufacturing method of the present invention.

FIG. 3 is a schematic cross-sectional view showing a layer structure of a laminated film of Example 5 which is one embodiment of the antireflection film of the present invention.

FIG. 4 is a schematic sectional view showing a layer structure of a laminated film of Example 6 which is another embodiment of the antireflection film of the present invention.

FIG. 5 is a schematic sectional view showing a section of the antireflection film of Example 4.

FIG. 6 shows reflection spectral characteristics of the antireflection film of Example 4.

FIG. 7 shows reflection spectral characteristics of the antireflection film of Comparative Example 3.

FIG. 8 shows reflection spectral characteristics of the laminated film of Example 5.

FIG. 9 shows reflection spectral characteristics of the laminated film of Example 6.

FIG. 10 is a schematic cross-sectional view illustrating a layer configuration of a laminated film of Comparative Example 5.

FIG. 11 shows reflection spectral characteristics of the laminated film of Comparative Example 5.

FIG. 12 is a schematic cross-sectional view illustrating a layer configuration of a laminated film of Comparative Example 6.

FIG. 13 shows reflection spectral characteristics of the laminated film of Comparative Example 6.

[Explanation of symbols]

 1, 21, 30: Polymer film 2, 22: Base material unwinding part 2 ', 26: Base material winding part 3, 23: Vacuum container 4, a, b, c: Reaction chamber 5: Vacuum pump 6, a2, b2, c2 source gas inlet 7 reversing roll 7 'reversing roll 8, 24 film forming drum 9, a1, b1, c1 electrode 10 power supply 11 plasma 12 titanium oxide film 25 isolation Wall 31 Hard coat layer 32 Medium refractive index layer 33 High refractive index layer 34 Low refractive index layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 1/11 G02F 1/1335 G02F 1/1335 G02B 1/10 A // C08L 1:12 67:00

Claims (10)

[Claims] 1. A method for forming at least one titanium oxide film on a polymer film controlled at a temperature within a range of -10 to 150 ° C. using a plasma CVD apparatus capable of controlling the temperature of the polymer film. A method for producing a laminated film. 2. Using the plasma CVD apparatus,
The method for producing a laminated film according to claim 1, wherein at least one silica film is formed on the polymer film controlled at a temperature in the range of -150 ° C. 3. A plasma CVD apparatus comprising: a reaction chamber into which at least a source gas is introduced; a film forming drum capable of controlling temperature; and a plasma generating means for generating plasma between the film forming drum. The film-forming drum continuously transports a web-like polymer film into a reaction chamber into which a raw material gas has been introduced, so that the temperature of the polymer film is controlled and at the same time, the polymer film is formed. 3. The method for producing a laminated film according to claim 1, wherein the apparatus is a device on which a film is formed. 4. The apparatus according to claim 3, wherein a plurality of the reaction chambers are arranged along an outer periphery of the film forming drum.
3. The method for producing a laminated film according to item 1. 5. A material having a refractive index of 2.0 to 2.9 (wavelength λ).
(550 nm) is formed by laminating at least one layer of a titanium oxide film on a polymer film by a plasma CVD method. 6. A plasma CVD method is performed on the polymer film on the surface of the polymer film on which the titanium oxide film is formed.
The antireflection film according to claim 5, wherein a silica film laminated by a method is formed. 7. The anti-reflection film according to claim 6, wherein the outermost layer is the silica film. 8. A hard coat layer is formed on the polymer film, and the plasma CV is formed on the hard coat layer.
The anti-reflection film according to any one of claims 5 to 7, wherein films formed by the method D are laminated. 9. The antireflection film according to claim 8, wherein a medium refractive index layer is formed on the hard coat layer. 10. The anti-reflection method according to claim 5, wherein the polymer film is a uniaxially or biaxially stretched polyester film, or a triacetyl cellulose film. the film.