KR20180092298A - Infrared cut off film, film type infrared cut off filter using the same and the manufacturing method theeby - Google Patents

Abstract

The present invention relates to an infrared cut-off film and a manufacturing method thereof. The infrared cut-off film comprises: a transparent film; a light absorption layer formed on at least one surface of the transparent substrate, and including a heat resistant resin, a heat resistant dye, and a non-heat resistant dye; an adhesive layer formed between the transparent substrate and the light absorption layer; and a heat-radiation layer formed on the light absorption layer.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an infrared ray blocking film, a film type infrared ray blocking filter including the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared ray shielding film, a film type infrared ray shielding filter comprising the same, and more particularly, to an infrared ray shielding film having no change in transmittance even when exposed to a high temperature for a long time, To an infrared cut filter and a manufacturing method thereof.

Recently, demand for digital camera modules using image sensors has increased significantly due to the spread of smart phones and tablet PCs. The development direction of the digital camera module used in such a mobile device is in the direction of pursuing thinning and high image quality.

The image signal of the digital camera module is received through an image sensor. The image sensor made of a semiconductor is designed to have a wavelength reactivity similar to that of a human being in the visible light region. However, since the image sensor has a characteristic of reacting even at the wavelength of the infrared region unlike the human eye, an infrared cut filter (IR Cut Filter) that blocks the wavelength of the infrared region to obtain image information similar to that of the human eye, .

These IR cut filters correspond to AR / IR coatings on both sides of the glass / plastic material at low pixel, but such a structure causes a change in spectral characteristics depending on the angle in a structure employing a high pixel, . IR cut filter including infrared region absorbing agent which can minimize this problem is widely used in structures adopting high-resolution.

In the case of the film type infrared cut filter including the absorbent, since the heat resistance is poor when the film is used at a high temperature for a long time, the dye properties are deteriorated due to the high temperature generated during IR / AR deposition, Lt; / RTI >

KR 2009-0074794 A

In order to solve the above problems,

The present invention provides an infrared ray blocking film and a film type infrared ray blocking filter which do not deteriorate dye characteristics due to high temperature generated during IR / AR deposition through the film-type infrared ray blocking filter having enhanced heat resistance and thus do not cause image distortion .

In order to achieve the above object,

The present invention relates to a transparent substrate; A light absorbing layer formed on at least one surface of the transparent substrate, the light absorbing layer comprising a heat resistant resin, a heat resistant dye and a non-heat resistant dye; An adhesive layer formed between the transparent substrate and the light absorbing layer; And a heat generating layer formed on the light absorbing layer.

Further, the present invention is a film type infrared cut filter comprising the infrared cut-off film,

Wherein at least one of an antireflection layer and an IR reflection layer is further formed on a heat generating layer formed on at least one side of the transparent substrate of the infrared ray blocking film.

The present invention also provides a method of manufacturing a transparent substrate, comprising the steps of: a) preparing a transparent substrate; b) forming an adhesive layer on at least one side of the transparent substrate; c) applying a composition for forming a light absorbing layer on the adhesive layer; d) drying the composition for forming a light absorbing layer applied in the step c); And e) forming a heat generating layer on the light absorbing layer formed in the step d).

The present invention also provides a method of manufacturing a transparent substrate, comprising the steps of: a) preparing a transparent substrate; b) forming an adhesive layer on at least one side of the transparent substrate; c) applying a composition for forming a light absorbing layer on the adhesive layer; d) drying the composition for forming a light absorbing layer applied in the step c); e) forming a heating layer on the light absorbing layer formed in step d); And f) forming at least one of an antireflection layer and an IR reflection layer on the heat generating layer formed in step e).

According to the film type infrared cut filter of the present invention,

Since heat resistance is enhanced compared to existing films because it contains a heating layer for maintaining the function of the dyes susceptible to heat, even if the film is used at a high temperature for a long period of time, An infrared ray blocking film and a film type infrared ray blocking filter including the infrared ray blocking film are provided.

1 is a schematic diagram showing an embodiment of an infrared cut filter according to the present invention.
2 is a graph showing the light transmittance before and after high temperature exposure of Example 1 according to the present invention.
3 is a graph showing the light transmittance of Comparative Example 1 according to the present invention before and after high temperature exposure.
4 is a graph comparing data after IR / AR deposition of Example 1 and Comparative Example 1 according to the present invention.
5 is an enlarged graph of FIG.

Hereinafter, the infrared ray shielding film of the present invention will be described in detail.

The present invention relates to a transparent substrate; A light absorbing layer formed on at least one surface of the transparent substrate, the light absorbing layer comprising a heat resistant resin, a heat resistant dye and a non-heat resistant dye; An adhesive layer formed between the transparent substrate and the light absorbing layer; And a heat generating layer formed on the light absorbing layer.

In the infrared ray blocking film of the present invention, the heat generated from the film is transferred to the transparent substrate to reduce module damage due to heat, thereby functioning as a heat shielding layer through a concentration gradient .

The transparent substrate of the present invention may be a glass substrate or a film which is transparent to visible light and can be used without any particular limitation. Preferably, the transparent substrate is glass, a cycloolefin polymer (COP), a polyimide ), Polyethyleneterephthalate (PET), polybutylene terephthalate, polyester, polymethylmethacrylate (PMMA), acrylic resin, polycarbonate (PC), polystyrene, triacetate resin, polyvinyl alcohol, Vinyl chloride, vinylidene chloride, polyethylene, ethylene-vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer, polyurethane, cellophane, and the like, (PET), polycarbonate (PC), polymethylmethacrylate (PMMA), and the like in view of high transparency And most preferably PET having excellent processability can be used.

Though the thickness of the transparent substrate varies depending on the use of the optical filter and the like, it is preferably 30 to 200 탆.

The infrared ray shielding film of the present invention comprises a light absorbing layer.

The light absorption layer of the present invention plays a role of preventing the dye characteristic from deteriorating due to the high temperature generated during the IR / AR deposition and thereby preventing image distortion. The light absorption layer can be formed on at least one surface of the transparent substrate, Specifically, it may be formed on at least one of the first surface and the second surface.

The light-absorbing layer includes a heat-resistant resin, a heat-resistant dye and a non-heat-resistant dye.

The thickness of the light absorption layer may be 0.1 to 50 탆, but is not limited thereto.

The heat resistant resin contained in the light absorbing layer may be selected from the group consisting of cycloolefin polymer (COP), polyimide (PI), polyethylene terephthalate (PET), polybutylene terephthalate, polyester, polymethyl methacrylate ), Acrylic resin and polycarbonate (PC), and the heat-resistant resin preferably has a glass transition temperature (Tg) of 150 ° C or higher.

The heat-resistant dye contained in the light-absorbing layer may be at least one selected from the group consisting of a squarylium compound, a cyanine compound, a phthalocyanine compound, a naphthalocyanine compound, and a dithiol metal complex, , It is preferable that the transmittance change of the maximum absorption due to heat is less than 0.5%.

The non-heat resistant dye contained in the light absorbing layer may be at least one selected from the group consisting of a squarylium compound, a cyanine compound, a phthalocyanine compound, a naphthalocyanine compound, and a dithiol metal complex, When exposed at 120 캜 for 96 hours or more, it is preferable that the transmittance change of the maximum absorption by heat is 0.5% or more.

The infrared ray shielding film of the present invention comprises an adhesive layer. The adhesive layer is a layer formed by a reaction between a solvent and a transparent substrate, and serves to hold the light absorbing layer and the transparent substrate from separating from each other. In order to produce the adhesive layer, usual adhesives used in the industry can be used.

The infrared ray shielding film of the present invention has an average transmittance in the range of 700 nm to 800 nm of not more than 20%, a maximum transmittance in the range of 700 nm to 800 nm of not more than 50%, preferably an average transmittance in the range of 750 nm to 800 nm , A maximum transmittance in a range of 750 nm to 800 nm is 50% or less, and a minimum transmittance in a range of 750 nm to 800 nm is 10% or less. The infrared ray blocking film of the present invention has the above-mentioned characteristics, thereby maximizing the infrared ray blocking of 700 nm and minimizing the image distortion.

The passivation layer of the present invention is formed on the light absorbing layer to maintain the function of the heat-sensitive dye. The function of the dye contained in the light absorbing layer can be conserved because the heat transfer rate and the amount of heat transmitted to the light absorbing layer through the heat generating layer can be reduced. The heating layer may be formed of a material selected from the group consisting of cycloolefin polymer (COP), polyimide (PI), polyethylene terephthalate (PET), polybutylene terephthalate, polyester, polymethylmethacrylate (PMMA) And polycarbonate (PC), and the heat generating layer preferably has a glass transition temperature (Tg) of 150 ° C or higher.

Also, in order to produce the above-mentioned infrared ray shielding film,

a) preparing a transparent substrate; b) forming an adhesive layer on at least one side of the transparent substrate; c) applying a composition for forming a light absorbing layer on the adhesive layer; d) drying the composition for forming a light absorbing layer applied in the step c); And e) forming a heat generating layer on the light absorbing layer formed in step d).

In the step a), the heat generated from the film is transferred to the transparent substrate to reduce module damage due to heat, and as a result, the transparent substrate functions as a heat shielding layer through a concentration gradient. The transparent film may be a transparent film that is transparent to visible light. However, it is preferable to use a transparent film such as a cycloolefin polymer (COP), a polyimide (PI), a polyethylene terephthalate (PET), a polybutyl (PMMA), acrylic resin, polycarbonate (PC), polystyrene, triacetate resin, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyethylene, ethylene- Vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer, polyurethane, cellophane, and the like can be used. More preferably, polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), and the like, and most preferably, You can use this excellent PET.

Though the thickness of the transparent film varies depending on the use of the optical filter and the like, it is preferably 30 to 100 탆.

Thereafter, in the step b), an adhesive layer is formed on at least one surface of the transparent substrate.

The adhesive layer is formed by spin coating at a speed of 3000 rpm or less for 1 second to 3 minutes, more preferably 1 second to 60 seconds, followed by curing at a temperature of room temperature to 200 ° C for 30 seconds to 10 minutes.

Thereafter, in the step c), a composition for forming a light absorbing layer is applied on the adhesive layer.

The composition for forming a light absorbing layer may include a heat-resistant resin, a heat-resistant dye, a non-heat-resistant dye and a solvent.

In this case, the solvent used in the industry may be any one generally used in the art without any particular limitation, but benzene, THF, toluene, hexane, chloroform or a mixed solvent thereof may be preferably used.

The heat-resistant resin, the heat-resistant dye and the non-heat-resistant dye are the same as those of the above-mentioned infrared ray shielding film.

Thereafter, in the step d), the composition for forming a light absorbing layer applied in the step c) is dried.

The drying process is performed at a temperature of 110 to 120 DEG C for 30 to 120 minutes.

Thereafter, in step e), a heating layer is formed on the light absorption layer formed in step d).

In order to form the heating layer, a composition for forming a heating layer is applied. The composition for forming a heating layer may include a heat-resistant resin and a solvent.

In this case, the solvent used in the industry may be any one generally used in the art without any particular limitation, but benzene, THF, toluene, hexane, chloroform or a mixed solvent thereof may be preferably used.

The heat-resistant resin is the same as that of the above-mentioned infrared ray blocking film.

The present invention also provides a film type infrared cut filter comprising the infrared cutoff film of the present invention, wherein at least one of the antireflection layer and the IR cutoff layer is formed on the heat generating layer formed on at least one surface of the transparent substrate of the infrared cutoff film The present invention also provides a film type infrared cut filter.

In the film type infrared cut filter of the present invention, the antireflection layer serves to prevent reflections of external light and reduce diffuse reflection which affects the contrast, and is provided on the top of the transparent film. For this purpose, the antireflection layer may have a reflectance of generally 3.0% or less, more preferably 1.8% or less. Also, a low refractive index layer may be used as the antireflection layer, and the refractive index of the antireflection layer may be lower than the refractive index of the transparent film. Specifically, the refractive index of the antireflection layer is preferably in the range of 1.20 to 1.55, and more preferably in the range of 1.30 to 1.50. The thickness of the antireflection layer may be 0.1 to 25 탆, but is not limited thereto.

The anti-reflection layer, the thing that has no particular limitation, but preferably, a silicon oxide (SiO _2), silicon nitride (SiN _x), titanium oxide (TiO _2), aluminum (Al) and aluminum oxide (Al ₂ O ₃₎ as May be used.

In the film type infrared cut filter of the present invention, the IR reflection layer refers to a layer that blocks IR in the infrared cut filter of the present invention. Specifically, it functions to reflect and block near infrared rays. In the present invention, the IR reflective layer may have the same physical properties as those of the anti-reflection layer. It to the IR reflecting layer include, but there is no particular limitation, but preferably, a silicon oxide (SiO _2), silicon nitride (SiN _x), titanium oxide (TiO _2), aluminum (Al) and aluminum oxide (Al ₂ O ₃₎ May be used.

The film type infrared cut filter of the present invention further comprises a light absorbing layer between the transparent substrate and either one of the antireflection layer and the IR reflection layer and including a light absorbing agent having an absorption maximum of 350 to 440 nm for improving cut on shift can do.

Also, in order to manufacture the above-described film type infrared cut filter,

a) preparing a transparent substrate; b) forming an adhesive layer on at least one side of the transparent substrate; c) applying a composition for forming a light absorbing layer on the adhesive layer; d) drying the composition for forming a light absorbing layer applied in the step c); e) forming a heating layer on the light absorbing layer formed in step d); And f) forming at least one of an antireflection layer and an IR reflection layer on the heat generating layer formed in step e).

In the method for manufacturing a film type infrared cut filter according to the present invention, the steps a) to e) are the same as those of the method for manufacturing the infrared cut film of the present invention.

In the method for manufacturing a film type infrared cut filter according to the present invention, at least one of an antireflection layer and an IR reflection layer is further formed on the heat generating layer formed in step e) in step f). The contents of the antireflection layer and the IR reflection layer are the same as those of the film type infrared ray cut filter described above.

The method for producing a film type infrared cut filter of the present invention comprises the steps of forming a light absorbing layer containing a light absorbing agent having an absorption maximum of 350 to 440 nm between any one of the antireflection layer and the IR reflection layer and the transparent substrate As shown in FIG.

In the adding step, the method of applying and drying the composition for forming a light absorbing layer, the antireflection layer and the IR reflection layer is the same as the contents of steps b) to d), and each step may be performed separately or simultaneously Can proceed.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Changes and modifications may fall within the scope of the appended claims.

Example

Synthetic example

[Synthesis Example 1]

When exposed to more than 96 hours of exposure to heat at 120 ° C, 0.08g of a heat-resistant dye with a maximum transmittance change of less than 0.5% (US Exciton AE-3 dye) and a transmittance change of maximal absorption by heat at 120 ° C 0.08 g of a non-heat resistant dye (AH-1 dye manufactured by Hayashibara Co., Ltd.) of 0.5% or more was mixed together with 40.0 g of chloroform as a solvent, and the mixture was polymerized and stirred for 10 hours to prepare a composition for forming a light absorbing layer.

[Synthesis Example 2]

40.0 g of chloroform as a solvent and 2.0 g of a polycarbonate resin as a binder resin were mixed and polymerized and stirred for 10 hours to prepare a composition for forming a heating layer.

Manufacture of infrared blocking film

[Example 1]

After preparing a transparent film (polycarbonate) of 100 占 퐉, the composition for forming a light absorbing layer prepared in Synthesis Example 1 was coated on the first surface of the transparent film to a thickness of 2 占 퐉 using a spin coater, Lt; / RTI > Thereafter, the composition for forming a light absorbing layer prepared in Synthesis Example 1 was coated on the second surface of the transparent film to a thickness of 2 탆 and dried at room temperature for 10 minutes to form a light absorbing layer on both sides of the transparent film.

Next, on the first surface of the film on which the light absorption layer was formed, the composition for forming a heat generating layer prepared in Synthesis Example 2 was coated to a thickness of 2 탆 and dried at room temperature for 10 minutes. On the second surface, The composition for forming a heating layer was coated to a thickness of 2 탆, and then dried in an oven at 110 캜 for 2 hours to form a passivation layer.

Then, TiO ₂ and SiO ₂ were alternately deposited on the first surface on which the heat generating layer was formed by an E-beam evaporator to form an antireflection layer having a thickness of 2.5 μm. Then, TiO ₂ and SiO ₂ were alternately deposited on the second surface on which the heat generating layer was formed by an E-beam evaporator to form an IR reflective layer of 2.9 μm, thereby manufacturing a film type infrared cut filter

 [Comparative Example 1]

After preparing a transparent film (polycarbonate) of 100 占 퐉, the composition for forming a light absorbing layer prepared in Synthesis Example 1 was coated on the first surface of the transparent film to a thickness of 2 占 퐉 using a spin coater, Lt; / RTI > Thereafter, the composition for forming a light absorbing layer prepared in Synthesis Example 1 was coated on the second surface of the transparent film to a thickness of 2 탆 and dried at room temperature for 10 minutes to form a light absorbing layer on both sides of the transparent film.

Thereafter, TiO ₂ and SiO ₂ were alternately deposited on the first surface on which the light absorption layer was formed by an E-beam evaporator to form an antireflection layer having a thickness of 2.5 μm. Then, TiO ₂ and SiO ₂ were alternately deposited on the second surface on which the light absorption layer was formed by an E-beam evaporator to form an IR reflective layer of 2.9 μm, thereby manufacturing a film-type IR cut filter

Experimental Example

Measurement of physical properties

The absorption and bending characteristics of the film-type infrared cut filter were measured as follows.

1. Light absorption property

The light absorption characteristics were confirmed by a transmittance using a Cary 5000 spectrometer (Agilent).

Hereinafter, the film type infrared ray blocking film produced in Example 1 and Comparative Example 1 was compared through a light absorption graph.

First, the light absorption layer (including the heat generating layer) formed on the first surface of Example 1 was exposed in an oven at 120 캜 for 96 hours, and then the light transmission graph before and after exposure was shown in Fig. 2, FIG. 3 shows a graph of light transmission before and after exposure of the light absorbing layer formed on the surface.

As can be seen from the comparison of the graphs of FIG. 2 and FIG. 3, in the case of Example 1 including the heating layer, the density of the dye in the environment of high temperature (120 ° C./96 hr) And it was found that there was little deterioration (Dye degradation).

The transmittance (%) from 700 nm to 850 nm of the film-type infrared cut filter prepared in Example 1 (passivation after deposition) and Comparative Example 1 (after deposition) was compared with the following Table 1 and Figs. 4 to 5 Respectively.

The infrared ray cut filter of Example 1 has a lower transmittance in the region of 700 to 850 nm in the near infrared region, which is a wavelength band sensitive to the image, as compared with the infrared cut filter of Comparative Example 1, It is possible to prevent flare and ghosting on the substrate.

Claims (18)

A transparent substrate;
A light absorbing layer formed on at least one surface of the transparent substrate, the light absorbing layer comprising a heat resistant resin, a heat resistant dye and a non-heat resistant dye;
An adhesive layer formed between the transparent substrate and the light absorbing layer; And
And a heat generating layer formed on the light absorbing layer. The method according to claim 1,
Wherein the infrared ray blocking film has an average transmittance in a range of 700 nm to 800 nm of 20% or less and a maximum transmittance in a range of 700 nm to 800 nm of 50% or less. The method of claim 2,
Wherein the infrared ray shielding film has an average transmittance in a range of 750 nm to 800 nm of 20% or less, a maximum transmittance in a range of 750 nm to 800 nm of 50% or less, a minimum transmittance in a range of 750 nm to 800 nm of 10% Infrared ray shielding film. The method according to claim 1,
The heat-resistant resin may be selected from the group consisting of cycloolefin polymer (COP), polyimide (PI), polyethylene terephthalate (PET), polybutylene terephthalate, polyester, polymethylmethacrylate (PMMA) Polycarbonate (PC), and has a glass transition temperature (Tg) of 150 DEG C or more. The method according to claim 1,
The heat-resistant dye is at least one selected from the group consisting of a squarylium compound, a cyanine compound, a phthalocyanine compound, a naphthalocyanine compound, and a dithiol metal complex. When the compound is exposed to 96 hours or more at 120 ° C, Wherein the transmittance change of the infrared ray shielding film is less than 0.5%. The method according to claim 1,
Wherein the non-heat resistant dye is at least one selected from the group consisting of a squarylium compound, a cyanine compound, a phthalocyanine compound, a naphthalocyanine compound, and a dithiol metal complex, Wherein the maximum transmittance change is 0.5% or more. The method according to claim 1,
The transparent substrate may be made of glass, a cycloolefin polymer (COP), a polyimide (PI), a polyethylene terephthalate (PET), a polybutylene terephthalate, a polymethyl methacrylate (PMMA) (PC), polystyrene, triacetate resin, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyethylene, ethylene-vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer , Polyurethane, and cellophane. ≪ RTI ID = 0.0 > 11. < / RTI > The method according to claim 1,
The transparent substrate has a thickness of 30 to 200 탆,
Wherein the light absorbing layer has a thickness of 0.1 to 50 占 퐉. The method according to claim 1,
The heating layer may be formed of a material selected from the group consisting of cycloolefin polymer (COP), polyimide (PI), polyethylene terephthalate (PET), polybutylene terephthalate, polyester, polymethylmethacrylate (PMMA) Polycarbonate (PC), and has a glass transition temperature (Tg) of 150 DEG C or more. A film type infrared cut filter comprising the infrared cutoff film of claim 1,
Wherein at least one of an antireflection layer and an IR reflection layer is further formed on a heat generating layer formed on at least one side of the transparent substrate of the infrared ray blocking film. The method of claim 10,
Further comprising a light absorbing layer comprising a light absorber having an absorption maximum of 350 to 440 nm between any one of the antireflection layer and the IR reflection layer and the transparent substrate. a) preparing a transparent substrate;
b) forming an adhesive layer on at least one side of the transparent substrate;
c) applying a composition for forming a light absorbing layer on the adhesive layer;
d) drying the composition for forming a light absorbing layer applied in the step c); And
e) forming a heat generating layer on the light absorbing layer formed in step d). The method of claim 12,
Wherein the infrared ray shielding film has an average transmittance in a range of 700 nm to 800 nm of 20% or less and a maximum transmittance in a range of 700 nm to 800 nm of 50% or less. The method of claim 12,
Wherein the infrared ray shielding film has an average transmittance in a range of 750 nm to 800 nm of 20% or less, a maximum transmittance in a range of 750 nm to 800 nm of 50% or less, a minimum transmittance in a range of 750 nm to 800 nm of 10% Lt; RTI ID = 0.0 > 1, < / RTI > The method of claim 12,
Wherein the composition for forming a light-absorbing layer comprises a heat-resistant resin, a heat-resistant dye, a non-heat-resistant dye and a solvent. 16. The method of claim 15,
Wherein the solvent is benzene, THF, toluene, hexane, chloroform or a mixed solvent thereof, and the binder resin is polycarbonate. a) preparing a transparent substrate;
b) forming an adhesive layer on at least one side of the transparent substrate;
c) applying a composition for forming a light absorbing layer on the adhesive layer;
d) drying the composition for forming a light absorbing layer applied in the step c);
e) forming a heating layer on the light absorbing layer formed in step d); And
f) forming at least one of an antireflection layer and an IR reflection layer on the heat generating layer formed in step e). 18. The method of claim 17,
Further comprising the step of forming a light absorbing layer including a light absorber having an absorption maximum of 350 to 440 nm between any one of the antireflection layer and the IR reflection layer and the transparent substrate. Way.

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