JP2009258362A - Near infrared cut filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a near-infrared cut filter, having superior transparency and near infrared cutting performance, without inclusion of glass pieces of a substrate as a foreign matter or cracking during cutting (punching), or without cracking in a near infrared reflecting film at a high temperature. <P>SOLUTION: The near infrared cut filter comprises a near-infrared reflecting film consisting of a dielectric multilayer film obtained by alternately laminating, on at least one surface of transparent substrate, including (A) a cyclic olefin-based resin and (B) a glass filler, a dielectric layer A and a dielectric layer B higher in the refractive index than that of the dielectric layer A. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a near-infrared cut filter. More specifically, the present invention has a structure in which a dielectric layer is laminated on a transparent substrate containing a cyclic olefin resin and a glass filler, and is particularly suitable as a visibility correction filter for a solid-state imaging device such as a CCD or CMOS. It relates to an infrared cut filter.

  In recent years, televisions equipped with plasma display panels (PDPs) have been commercialized and have become widespread in ordinary households. This PDP is a display that operates using plasma discharge, but it is known that near infrared rays (wavelength: 800 to 1,000 nm) are generated during plasma discharge.

  On the other hand, in homes, near-infrared rays are often used for remote control of home appliances such as TVs, stereos or air conditioners, and also for information exchange by personal computers. It has always been pointed out that it is likely to cause malfunctions.

Therefore, many of the commercially available PDPs are provided with a filter function for cutting near infrared rays emitted from the front plate.
In addition, CCDs and CMOS image sensors, which are solid-state image pickup devices for color images, are used in video cameras, digital still cameras, mobile phones with camera functions, etc., and these solid-state image pickup devices are sensitive to near-infrared light at their light receiving parts. Therefore, it is necessary to perform visibility correction, and a near-infrared cut filter is often used.

  As a near-infrared cut filter, what was conventionally manufactured by various methods is used. For example, a metal such as silver deposited on the surface of a transparent substrate such as glass to reflect near infrared rays, or a transparent substrate such as glass, acrylic resin or polycarbonate resin with a near infrared absorbing dye added Etc. are provided for practical use.

  However, the near-infrared cut filter in which metal is vapor-deposited on a glass base material is not only expensive to manufacture, but the glass piece of the base material is mixed as a foreign substance or a crack occurs during cutting (at the time of punching). There was a problem.

On the other hand, a near-infrared cut filter in which a near-infrared reflective film is laminated on one surface of a transparent resin having a low linear expansion coefficient as a base material and a functional film is laminated on the other surface is also known (for example, Patent Documents). 1). However, there is a problem that the manufacturing cost is increased because the functional films are laminated. Further, when a transparent resin is used as the base material, the heat resistance is inferior to that of the glass substrate at a high temperature, so that the substrate expands and contracts, thereby causing a problem that a near-infrared reflective film is cracked.
JP 2006-30944 A

The present invention has been made in view of such circumstances, and there is no mixing of glass fragments or cracks in the base material as foreign matters during cutting (during punching), and the near-infrared reflecting film is formed at high temperatures. An object of the present invention is to provide a near-infrared cut filter excellent in transparency and near-infrared cut ability that does not generate cracks.

  As a result of intensive studies in view of the above problems, the present inventors have found that the above problems can be solved by a near-infrared cut filter having a structure in which a dielectric layer is laminated on a transparent substrate containing a cyclic olefin-based resin and a glass filler. The headline and the present invention were completed.

  That is, the near-infrared cut filter of the present invention has a dielectric layer A and a refraction that the dielectric layer A has on at least one surface of a transparent substrate containing (A) a cyclic olefin resin and (B) a glass filler. And a near-infrared reflective film comprising a dielectric multilayer film in which dielectric layers B having a refractive index higher than the refractive index are alternately laminated.

  (A) It is preferable that cyclic olefin resin has a structural unit derived from the compound represented by following formula (1).

（式中、Ｒ¹〜Ｒ⁴は、それぞれ独立に、水素原子、ハロゲン原子、炭素数１〜３０の炭化水素基またはその他の１価の有機基を表し、Ｒ¹〜Ｒ⁴のうち任意の２つが互いに結合して、単環または多環構造を形成してもよく、ｍおよびｐは、それぞれ独立に、０または正の整数を表す。）
（Ａ）環状オレフィン系樹脂は、上記式（１）で表される化合物を開環（共）重合した後、水素添加した重合体であることが好ましい。

(In the formula, R ^{1 to} R ⁴ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or other monovalent organic group, and any ^one of R ^{1 to} R ⁴ may be used. Two may be bonded to each other to form a monocyclic or polycyclic structure, and m and p each independently represent 0 or a positive integer.)
(A) The cyclic olefin-based resin is preferably a polymer obtained by subjecting the compound represented by the formula (1) to ring-opening (co) polymerization and then hydrogenation.

(B) The glass filler is preferably a glass cloth.
The dielectric layer A is made of silica (SiO ₂ ), and the dielectric layer B is made of titania (Ti
O ₂ ) is preferred.

  Moreover, the manufacturing method of the near-infrared cut filter of this invention is the dielectric material layer A and this dielectric material layer A on the at least one surface of the transparent substrate containing (A) cyclic olefin resin and (B) glass filler. Characterized in that it includes a step of forming, by vacuum deposition, a near-infrared reflective film made of a dielectric multilayer film in which dielectric layers B having a refractive index higher than the refractive index possessed are alternately laminated. .

  According to the present invention, it is possible to provide a near-infrared cut filter that is free from cracks in the near-infrared layer at a high temperature and does not generate cracks even by punching and has excellent transparency and near-infrared cutting ability. Furthermore, since the near infrared cut filter of the present invention can sharply cut near infrared rays, it is particularly suitable as a visibility correction filter for a solid-state imaging device such as a CCD or CMOS.

  The near-infrared cut filter of the present invention has a dielectric layer A and a refractive index of the dielectric layer A on at least one surface of a transparent substrate containing (A) a cyclic olefin resin and (B) a glass filler. And a near-infrared reflective film comprising a dielectric multilayer film in which dielectric layers B having a high refractive index are alternately laminated.

Hereinafter, the near-infrared cut filter of the present invention will be described in detail.
<Transparent substrate>
The transparent substrate contains (A) a cyclic olefin resin and (B) a glass filler.

[(A) Cyclic olefin resin]
(A) The cyclic olefin-based resin is obtained by ring-opening (co) polymerization or addition (co) polymerization of a monomer (composition) containing a cyclic olefin monomer, as follows: (Co) polymers.

(I) A ring-opening (co) polymer of a compound represented by the following formula (1).
(Ii) A ring-opening copolymer of a compound represented by the following formula (1) and a copolymerizable monomer.

(Iii) A hydrogenated product of the ring-opening (co) polymer of (i) or (ii).
(Iv) A (co) polymer obtained by cyclization of the ring-opening (co) polymer of (i) or (ii) by Friedel-Craft reaction and then hydrogenation.

(V) A saturated copolymer of a compound represented by the following formula (1) and an unsaturated double bond-containing compound.
(Vi) an addition (co) polymer of at least one monomer selected from the group consisting of a compound represented by the following formula (1), a vinyl cyclic hydrocarbon monomer, and a cyclopentadiene monomer And its hydrogenated product.

  (Vii) An alternating copolymer of a compound represented by the following formula (1) and an acrylate.

（式中、Ｒ¹〜Ｒ⁴は、それぞれ独立に、水素原子、ハロゲン原子、炭素数１〜３０の炭化水素基またはその他の１価の有機基を表し、Ｒ¹〜Ｒ⁴のうち任意の２つが互いに結合して、単環または多環構造を形成してもよく、ｍおよびｐは、それぞれ独立に、０または正の整数を表す。）
これらの中でも、（ｉｉｉ）が樹脂の耐熱性、耐候性、耐湿性、機械的強度、易成型性の観点から好適である。

(In the formula, R ^{1 to} R ⁴ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or other monovalent organic group, and any ^one of R ^{1 to} R ⁴ may be used. Two may be bonded to each other to form a monocyclic or polycyclic structure, and m and p each independently represent 0 or a positive integer.)
Among these, (iii) is preferable from the viewpoints of heat resistance, weather resistance, moisture resistance, mechanical strength, and easy moldability of the resin.

Specific examples of the compound represented by the above formula (1) include the following compounds, but the present invention is not limited to these specific examples.
Bicyclo [2.2.1] hept-2-ene,
Tricyclo [4.3.0.1 ^2,5 ] -8-decene,
Tricyclo [4.4.0.1 ^2,5 ] -3-undecene,
Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
Pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] -4-pentadecene,
5-methylbicyclo [2.2.1] hept-2-ene,
5-ethylbicyclo [2.2.1] hept-2-ene,
5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-cyanobicyclo [2.2.1] hept-2-ene,
8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-isopropoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3
-Dodecene,
8-methyl-8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3
-Dodecene,
8-methyl-8-n-propoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10
] -3-dodecene,
8-methyl-8-isopropoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10
] -3-dodecene,
8-methyl-8-n-butoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ]
-3-dodecene,

5-ethylidenebicyclo [2.2.1] hept-2-ene,
8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
5-phenylbicyclo [2.2.1] hept-2-ene,
8-phenyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
5-fluorobicyclo [2.2.1] hept-2-ene,
5-fluoromethylbicyclo [2.2.1] hept-2-ene,
5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-pentafluoroethylbicyclo [2.2.1] hept-2-ene,
5,5-difluorobicyclo [2.2.1] hept-2-ene,
5,6-difluorobicyclo [2.2.1] hept-2-ene,
5,5-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5,5,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,5,6-tris (fluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrafluorobicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrakis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,

5,5-difluoro-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-fluoro-5-pentafluoroethyl-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5-heptafluoro-isopropyl-6-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-chloro-5,6,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,6-dichloro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-trifluoromethoxybicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-heptafluoropropoxybicyclo [2.2.1] hept-2-ene,

8-fluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-fluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-difluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-pentafluoroethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3
-Dodecene,
8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3
-Dodecene,
8-methyl-8-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3
-Dodecene,
8,8,9-trifluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-tris (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10
] -3-dodecene,
8,8,9,9-tetrafluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9,9-tetrakis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5
. 1 ^7,10 ] -3-dodecene,
8,8-difluoro-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluoro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5
. 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-trifluoromethoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,8,9-trifluoro-9-pentafluoropropoxytetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-fluoro-8-pentafluoroethyl-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8,9-difluoro-8-heptafluoroisopropyl-9-trifluoromethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-chloro-8,9,9-trifluorotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] −
3-dodecene,
8,9-dichloro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8- (2,2,2-trifluoroethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8- (2,2,2-trifluoroethoxycarbonyl) tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene.

These can be used alone or in combination of two or more.
R ¹ and R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms. The hydrocarbon group is preferably an alkyl group, preferably an alkyl group having 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably a methyl group. When such an alkyl group is bonded to a carbon atom to which a polar group represented by the following formula: — (CH ₂ ) _n COOR, which will be described later, is bonded, the hygroscopicity of the obtained (A) cyclic olefin-based resin is increased. This is preferable because it can be lowered.

R ² and R ⁴ are preferably each independently a hydrogen atom or a monovalent polar group.
Examples of the monovalent polar group include a carboxyl group, a hydroxyl group, an alkoxycarbonyl group, an allyloxycarbonyl group, an amino group, an amide group, and a cyano group. These polar groups may be bonded via a linking group having no polarity such as a methylene group, or a divalent group having polarity such as a carbonyl group, an ether group, a silyl ether group, a thioether group, or an imino group. It may be bonded via an organic group. Of these polar groups, a carboxyl group, a hydroxyl group, an alkoxycarbonyl group, and an allyloxycarbonyl group are preferable, and an alkoxycarbonyl group and an allyloxycarbonyl group are particularly preferable.

When the polar group is represented by the formula:-(CH ₂ ) _n COOR, the obtained (A) cyclic olefin-based resin has high glass transition temperature, low hygroscopicity, and excellent adhesion to various materials. This is preferable.

In the above formula: — (CH ₂ ) _n COOR, R is a hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, preferably an alkyl group. It is desirable to be. n usually represents 0 to 5, but preferably represents 0 to 3. The smaller the value of n, the higher the glass transition temperature of the obtained (A) cyclic olefin-based resin, which is preferable. Further, when n represents 0, the synthesis is also easy.

  M and p each independently desirably represent an integer of 0 to 3, preferably satisfy m + p = 0 to 4, more preferably m + p = 0 to 2, and p = 0 when m = 1. It is particularly preferred. When m = 1 and p = 0, the obtained (A) cyclic olefin-based resin has a high glass transition temperature and is excellent in mechanical strength, which is preferable.

  In the present invention, the (A) cyclic olefin-based resin can be obtained by a known method, for example, as described in JP-A-1-132626, JP-A-2006-77257, and JP-A-2008-955. It can be obtained by a method.

(A) The molecular weight of the cyclic olefin resin is intrinsic viscosity [η] _inh , preferably 0
. 2-5 dL / g, more preferably 0.3-3 dL / g, still more preferably 0.4-1.
5 dL / g. The number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC) after being dissolved in tetrahydrofuran is preferably 8,000 to 100,000, more preferably 10,000 to 80,000, still more preferably. Is 12,000 to 50,000, and the weight average molecular weight (Mw) is preferably 20,000 to 300,000, more preferably 30,000 to 250,000, and even more preferably 40,000 to 200,000. The thing of the range is suitable. Moreover, molecular weight distribution (Mw / Mn) becomes like this. Preferably it is 2.0-4.0, More preferably, it is 2.5-3.7, More preferably, it is 2.8-3.5. Use of a resin having a small molecular weight distribution is preferable because a molded article having excellent mechanical strength can be obtained.

A molded article having excellent mechanical strength can also be obtained by having the intrinsic viscosity [η] _inh , the number average molecular weight and the weight average molecular weight within the above ranges.
[(B) Glass filler]
(B) Examples of the glass filler include glass fiber, glass cloth, glass fiber cloth (glass nonwoven fabric / woven cloth), glass beads, glass flakes, glass powder, milled glass, and the like. Glass cloth and glass fiber cloth are preferable because a composite having excellent mechanical strength and heat resistance is obtained.

  Examples of the glass include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, low dielectric constant glass, and high dielectric constant glass, but ionic impurities such as alkali metals are used. E glass, S glass, and NE glass, which are easily available, are preferable.

When glass cloth is used as the glass filler, the weaving method is not particularly limited, and plain weaving, twill weaving, satin weaving, tangle weaving, imitation weaving, and the like are applicable, and plain weaving is preferred.
The thickness of the glass cloth is usually preferably 15 to 200 μm, more preferably 15 to 100 μm. Only one glass cloth may be used, or a plurality of glass cloths may be used.

  (B) In order to improve the adhesion between the glass filler and (A) the cyclic olefin resin, the surface of the glass filler is treated with a silane coupling agent such as aminosilane, styrylsilane, epoxysilane, methacryloxysilane, acryloxysilane, or vinylsilane. Or a metal chelate compound such as an aluminum chelate compound. When such a surface treatment is applied, the adhesion between the (B) glass filler and the (A) cyclic olefin-based resin is increased, so the transparency of the sheet made of the transparent composite can be increased. Furthermore, it is possible to suppress a decrease in transparency due to interfacial peeling between the glass filler surface and the polymer that occurs when the sheet is repeatedly bent.

[Transparent substrate]
As described above, the transparent substrate is composed of (A) a cyclic olefin resin and (B) a glass filler.

The light transmittance at a wavelength of 400 nm of the transparent substrate is 80% or more, preferably 85% or more. Those having such light transmittance have high transparency. In order to obtain a light transmittance of 80% or more at a wavelength of 400 nm, it is necessary to adjust the refractive index difference between (A) the cyclic olefin resin and (B) the glass filler within 0.01, and (A) the cyclic olefin resin. The composition of (B) can be changed to match the refractive index of the glass filler, or (A) the glass filler that matches the refractive index of the cyclic olefin resin can be used.

The refractive index difference between (A) the cyclic olefin resin and (B) the glass filler is preferably 0.01 or less, more preferably 0.005 or less. When the refractive index difference exceeds 0.01, the transparency of the obtained transparent substrate may be inferior.

  The average linear expansion coefficient at 50 to 140 ° C. of the transparent substrate is desirably 60 ppm / ° C. or less. If it exists in this range, since the dimensional stability of the transparent substrate with temperature is high and there is little optical anisotropy, it becomes suitable for a glass substitute use.

  The content of the (B) glass filler in the transparent substrate is preferably 10 to 70% by weight, more preferably 30 to 50% by weight. (B) If the content of the glass filler is less than the above lower limit, the effect of reducing linear expansion due to compounding is not recognized, and if it exceeds the above upper limit, the mechanical strength is greatly reduced, and the plastics Bending strength, which is an important feature of the substrate, is insufficient, and it may not be possible to reduce the weight.

The transparent substrate is suitable for a sheet having a thickness of 50 to 200 μm from the viewpoint of bendability and easy moldability.
The transparent substrate usually has a shape such as a film or a sheet. As a method for forming a transparent substrate, (A) a glass filler, preferably a glass cloth, is immersed in a solution in which a cyclic olefin-based resin is dissolved, and then taken out, for example, dried at room temperature to 200 ° C., A method in which the obtained glass filler is sandwiched between two sheets of (A) cyclic olefin-based resin, usually having a thickness of 20 to 1,000 μm, and heat compression molding is desirable.

  The preferable conditions for the immersion are immersion time: 1 to 60 minutes, more preferably 5 to 30 minutes, and immersion temperature: room temperature to 40 ° C. is desirable. If the immersion time is less than 1 minute, impregnation may be insufficient. If the immersion temperature exceeds 40 ° C., the amount of resin in the solution may increase due to solvent volatilization, which may result in impregnation failure.

  As preferable conditions for the heat compression molding, temperature: 200 to 300 ° C., degree of vacuum: 100 to 1 torr, pressure: 5 to 15 MPa, and time: 5 to 20 minutes are desirable. When the temperature, pressure and time of heat compression molding are less than the above lower limit values, the sheet and the (B) glass filler may have poor adhesion, and the transparency of the substrate may be lowered. In addition, when the temperature and time of heat compression molding exceed the above upper limit value or the degree of vacuum is less than the above lower limit value, (A) the cyclic olefin-based resin is thermally deteriorated and / or oxidized and deteriorated. It may become. Furthermore, if the pressure of heat compression molding exceeds the above upper limit, the shape of the (B) glass filler may be deformed, and a uniform substrate may not be obtained.

  Alternatively, (B) glass filler is immersed in a solution in which (A) cyclic olefin-based resin is dissolved, rolled between metal rolls, and dried at 150 to 300 ° C., for example, to obtain a transparent substrate. Furthermore, after applying the solution in which (A) cyclic olefin resin melt | dissolved to the single side | surface or both surfaces of the sheet | seat, the method of drying at 150-300 degreeC, for example, etc. are also employ | adopted. be able to.

  Furthermore, the operation of (B) glass filler being immersed in a solution in which (A) the cyclic olefin-based resin is dissolved, rolled between metal rolls, and then dried may be repeated a plurality of times.

As described above, the solid content concentration of the solution in which the cyclic olefin-based resin (A) used for the production of the transparent substrate is dissolved is desirably 3 to 50% by weight, and more preferably 3 to 30% by weight. %It is in. If the solution concentration is too low, the impregnating resin may be insufficient and the transparency of the substrate may be reduced. Conversely, if the solution concentration is high, the solution viscosity may be increased, resulting in poor impregnation.

  (A) As a preferable solvent for dissolving the cyclic olefin-based resin, for example, alkanes such as pentane, hexane, heptane, octane, nonane, decane; cycloalkanes such as cyclohexane, cycloheptane, cyclooctane, decalin, norbornane; Aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene; halogenated alkanes such as chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chloroform, tetrachloroethylene; halogenated aryl compounds such as chlorobenzene; ethyl acetate Saturated carboxylic acid esters such as n-butyl acetate, iso-butyl acetate, methyl propionate, and dimethoxyethane; Such as Le acids and the like. These can be used individually by 1 type or in mixture of 2 or more types.

  (B) As described above, the glass filler is prepared in advance by using a silane coupling agent or a metal chelate compound such as aminosilane, styrylsilane, epoxysilane, methacryloxysilane, acryloxysilane, and vinylsilane, and (A) a cyclic olefin resin. It may be processed with the solution containing these. As such a treatment, (B) the glass filler is immersed in the solution and then dried at a temperature of 150 to 300 ° C. Although it does not restrict | limit especially as a density | concentration at this time, In the case of containing a silane coupling agent or a metal chelate compound, 1-50 weight% and (A) cyclic olefin resin, it is 3-50 weight% Is preferable in terms of processing conditions, processing efficiency, and the like.

<Near-infrared reflective film>
The near-infrared cut filter of the present invention is a near-infrared reflective film comprising a dielectric multilayer film in which dielectric layers A and dielectric layers B having a refractive index higher than that of the dielectric layer A are alternately laminated. Have By having such a dielectric multilayer film on at least one surface of the transparent substrate, a near-infrared cut filter having an excellent ability to reflect near-infrared light can be obtained. Further, the difference in refractive index between the dielectric layer A and the dielectric layer B is preferably 0.5 or more, and more preferably 1.0 or more. When the difference in refractive index is 1.0 or more, the wavelength range of the near infrared region that can be cut is widened, and a filter having better near infrared ray cutting performance can be obtained.

[Dielectric layer A]
As a refractive index of the material which comprises the dielectric material layer A, it is 1.6 or less normally, and 1.2-1.6 are preferable. Examples of such a material include silica (SiO ₂ ), alumina, lanthanum fluoride, magnesium fluoride, sodium hexafluoride sodium, and the like.

[Dielectric layer B]
As a refractive index of the material which comprises the dielectric material layer B, it is 1.7 or more normally, and 1.7-2.5 are preferable. As such a material, for example, titanium oxide (titania (TiO ₂ ))
Zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, indium oxide, etc. as main components, and small amounts of titanium oxide (titania (TiO ₂ )), tin oxide, cerium oxide, etc. The thing etc. which were made to contain are mentioned.

[Lamination method]
The method of laminating the dielectric layer A and the dielectric layer B is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a CVD method, a sputtering method, a vacuum deposition method, etc. Thus, a dielectric multilayer film can be formed by alternately laminating the dielectric layers A and B.

The thickness of each of the dielectric layer A and the dielectric layer B is usually determined by the near infrared wavelength λ to be blocked.
(Nm) of 0.1λ to 0.5λ. If the thickness is out of the above range, the product (n × d) of the refractive index (n) and the film thickness (d) is greatly different from the optical film thickness calculated by λ / 4. There is a tendency that the relationship between the optical characteristics is broken, and control for blocking / transmitting a specific wavelength cannot be performed.

  The number of laminated dielectric layers A and B is usually 10 to 80 layers, preferably 25 to 50 layers, when the dielectric multilayer film is provided only on one surface of the transparent substrate. On the other hand, when the dielectric multilayer film is provided on both surfaces of the transparent substrate, the total number of layers on both surfaces of the substrate is generally 10 to 80 layers, preferably 25 to 50 layers.

  Moreover, when using the thermoplastic resin containing a near-infrared absorber as a transparent substrate, the lamination | stacking number in the case of having a dielectric multilayer film only on one side of a transparent substrate is 5-40 layers normally, Preferably it is 10 When there are 30 layers and the dielectric layer films are provided on both sides of the transparent substrate, the total number of layers on both sides of the substrate is usually 5 to 40 layers, preferably 10 to 30 layers.

<Near-infrared cut filter>
The near-infrared cut filter of the present invention has a dielectric layer A and a refractive index of the dielectric layer A on at least one surface of a transparent substrate containing (A) a cyclic olefin resin and (B) a glass filler. And a near-infrared reflective film comprising a dielectric multilayer film in which dielectric layers B having a high refractive index are alternately laminated, wherein the dielectric layer A is silica (SiO _2).
It is preferable that the dielectric layer B is made of titania (TiO ₂ ) because of excellent near-infrared cut performance.

<Method for manufacturing near-infrared cut filter>
The manufacturing method of the near-infrared cut filter of this invention has the dielectric material layer A and this dielectric material layer A on the at least one surface of the transparent substrate containing (A) cyclic olefin resin and (B) glass filler. The method includes a step of forming a near-infrared reflective film made of a dielectric multilayer film in which dielectric layers B having a refractive index higher than the refractive index are alternately laminated by a vacuum deposition method.

Moreover, as a manufacturing method of the near-infrared cut filter of this invention, you may include the process of bonding the said near-infrared reflective film on the said transparent substrate with an adhesive agent instead of the said process.
By forming the near-infrared cut filter in this way, a near-infrared cut filter excellent in transparency and near-infrared cut ability can be obtained without cracking in the near-infrared reflective film at high temperatures.

Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited by these. “Parts” represents “parts by weight” unless otherwise specified.
Various physical properties were measured according to the methods described in (1) to (9) below.

(1) Hydrogenation rate The nuclear magnetic resonance spectrometer (NMR) was measured using ¹ H-NMR by using AVANCE 500 manufactured by Bruker, using d-chloroform as a measurement solvent. After calculating the monomer composition from the integral value of 5.1 to 5.8 ppm vinylene group, 3.7 ppm methoxy group, and 0.6 to 2.8 ppm aliphatic proton, the hydrogenation rate (%) is calculated. Calculated.

(2) Glass transition temperature (Tg)
Using a DSC6200 manufactured by Seiko Instruments Inc., the temperature increase rate was measured at 20 ° C. per minute under a nitrogen stream. Tg (° C) is the maximum peak temperature (point A) of differential differential scanning calorific value and the temperature (point B) of -20 ° C from the maximum peak temperature (point A) is plotted on the differential scanning calorimetry curve. As the intersection of the tangent on the baseline and the tangent starting from point A.

(3) Number average molecular weight (Mn), weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn)
Gel permeation chromatography (Tosoh Co., Ltd. HLC-8220GPC, column: Tosoh Co., Ltd. guard column H _XL- H, TSK gel G7000H _XL , TSKgel GMH _XL , TSK gel G2000H _XL , sequentially connected, solvent: Tetrahydrofuran, flow rate: 1 mL / min, sample concentration: 0.7 to 0.8% by weight, injection amount: 70 μL, measurement temperature: 40 ° C., detector: RI (40 ° C.), standard material: manufactured by Tosoh Corporation The number average molecular weight (Mn), the weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were measured using TSK standard polystyrene.

(4) Logarithmic viscosity Using an Ubbelohde viscometer, in chloroform (sample concentration: 0.5 g / dL), 30 ° C.
The logarithmic viscosity (dL / g) was measured.

(5) Residual solvent amount The cyclic olefin resin sheet (a1) obtained in Production Example 1 was dissolved in methylene chloride, and the resulting solution was subjected to gas chromatography (Shimadzu Corporation GC-7A) using a residual solvent amount. (%) Was analyzed.

(6) Total light transmittance The total light transmittance (%) was measured using the Gardner haze-light transmittance measuring machine (Haze-Gard Plus type).

(7) Evaluation of near-infrared cutting ability The laminated films obtained in Examples 1 and 2 and Comparative Example 1 were cut into 1 cm × 2 cm, and UV-vis spectrum measuring apparatus (V-570) manufactured by JASCO Corporation. Then, the absorption spectrum of the laminated film was measured in the region of 450 nm to 1,000 nm.

(8) Evaluation of heat-resistant cracking properties The laminated films obtained in Examples 1 and 2 and Comparative Example 1 were cut into 3 cm square, and four sides were fixed to the glass epoxy substrate with imide tape. This laminated film fixed substrate was placed in a circulation thermostat (DK-43 type manufactured by Yamato Scientific Co., Ltd.) and heated at 100 ° C. for 30 minutes or 130 ° C. for 30 minutes. Then, it took out from the thermostat, observed the near-infrared cut layer of the laminated film with a 40 magnification microscope, and confirmed the presence or absence of cracks. The case where there are no cracks is “◯”, and the case where one or more cracks are observed is “x”.

(9) Evaluation of punchability Five laminated films obtained in Examples 1 and 2 and Comparative Example 1 were punched at 10 mmΦ with a sample cutter manufactured by Dumbbell Co., Ltd. The laminated films punched out were each observed with a 40 magnification microscope, and the number of cracks generated was counted over the entire laminated film.

[Synthesis Example 1]
8-methyl-8-methoxycarbonyltetracyclo represented by the following formula (2) [4.4.0.1 ^2,5 . 1 ^{7, 10} ] -3-dodecene (DMN) 71 parts, dicyclopentadiene (DCP) 15 parts represented by the following formula (3), and bicyclo [2.2. 1] 1 part of hept-2-ene (NB), 18 parts of 1-hexene (molecular weight regulator), toluene (
200 parts of a solvent for ring-opening polymerization reaction) was charged into a nitrogen-substituted reaction vessel and heated to 100 ° C.

これにトリエチルアルミニウム０．００５部、メタノール変性ＷＣｌ₆（無水メタノー
ル：ＰｈＰＯＣｌ₂：ＷＣｌ₆＝１０３：６３０：４２７（重量比））０．００５部を加えて１分間反応させ、次いで、ＤＣＰ１０部とＮＢ３部を５分間かけて追加添加して、さらに４５分間反応させることにより、ＤＮＭ／ＤＣＰ／ＮＢ＝６９．７７／２６．０１／４．２３（重量％）の共重合体を得た。

To this, 0.005 part of triethylaluminum and 0.005 part of methanol-modified WCl ₆ (anhydrous methanol: PhPOCl ₂ : WCl ₆ = 103: 630: 427 (weight ratio)) were added and reacted for 1 minute. An additional 3 parts of NB was added over 5 minutes, and the mixture was further reacted for 45 minutes to obtain a copolymer of DNM / DCP / NB = 69.77 / 26.01 / 4.23 (% by weight).

Next, the obtained copolymer solution was placed in an autoclave, and 200 parts of toluene was further added. Next, 1 part of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a reaction modifier and RuHCl (CO) [P (C ₆ H ₅ )] as a hydrogenation catalyst _After adding 0.006 part of ₃ and heating to 155 ° C, hydrogen gas was charged into the reactor,
The pressure was 10 MPa. Thereafter, the reaction was carried out at 165 ° C. for 3 hours while maintaining the pressure at 10 MPa. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a coagulated product, which was dried to obtain a hydrogenated polymer.

The obtained hydrogenated polymer was used as a cyclic olefin resin (A1), and ¹ H of the resin (A1) was obtained.
-Hydrogenation rate measured by NMR was 99.9%, Tg measured by DSC method was 131 ° C, Mn by polystyrene conversion measured by GPC method was 16,000, Mw was 61,000, and Mw / Mn was 3. The logarithmic viscosity in chloroform at 81 and 30 ° C. was 0.52 dL / g.

[Production Example 1]
To 100 parts by weight of the cyclic olefin-based resin (A1), 0.5 part by weight of pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl)] propionate is added as an antioxidant, The resin solution was dissolved in 400 parts by weight of methylene chloride, and the resin solution was filtered using a membrane filter made of ADVANTEC having a pore diameter of 5 μm. The obtained resin solution was cast at 25 ° C. using an applicator so that the thickness after drying was 80 μm, allowed to stand at room temperature for 12 hours to evaporate the solvent, and then kept at 100 ° C. under vacuum for 120 minutes. As a result, a cyclic olefin-based resin sheet (a1) was obtained. The residual solvent amount of the residual solvent amount of the obtained sheet (a1) was 0.1% or less.

[Production Example 2]
To 100 parts by weight of the cyclic olefin-based resin (A1), 0.5 part by weight of pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl)] propionate is added as an antioxidant, The resin solution was dissolved in 900 parts by weight of toluene, and the resin solution was filtered using a membrane filter made of ADVANTEC having a pore diameter of 5 μm. The obtained resin solution was put into a stainless steel bat, and a glass filler (B1) obtained by cutting Nittobo glass cloth NE2116 (thickness 95 μm) into 15 cm × 22 cm was soaked for 10 minutes, and the glass filler (B1 ) Was impregnated with cyclic olefin resin (A1). Thereafter, the glass filler (B1) impregnated with the cyclic olefin resin (A1) was taken out, air-dried for 1 hour, and further dried at 100 ° C. for 2 hours under vacuum. The product thus obtained is designated as transparent substrate (b1).

  The transparent substrate (b1) is sandwiched between two cyclic olefin resin sheets (a1) cut into 18 cm × 25 cm, and further sandwiched between polyimide films made by Toray DuPont Co., Ltd. as a protective film. ) Press for 10 minutes at a temperature of 260 ° C., a degree of vacuum of 14 torr, and a pressure of 7.5 MPa using a vacuum press (J2008010MHPCV750 type). Thereafter, the protective film was peeled off, and as a result, a transparent glass cloth composite film was obtained. Let the obtained glass cloth composite film be a composite film (c1).

The thickness of the composite film (c1) was 150 μm, and the total light transmittance was 94%.
[Production Example 3]
To 100 parts by weight of the cyclic olefin-based resin (A1), 0.5 part by weight of pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl)] propionate is added as an antioxidant, The resin solution was dissolved in 900 parts by weight of toluene, and the resin solution was filtered using a membrane filter made of ADVANTEC having a pore diameter of 5 μm. The obtained resin solution was put into a stainless steel bat, and a glass filler (B2) was cut by immersing a Nittobo glass cloth (WTX1080) (thickness 55 μm) cut into 15 cm × 22 cm for 10 minutes. (B2) was impregnated with the cyclic olefin resin (A1). Thereafter, the glass filler (B2) impregnated with the cyclic olefin resin (A1) was taken out, air-dried for 1 hour, and further dried at 100 ° C. for 2 hours under vacuum. The product thus obtained is designated as a transparent substrate (b2).

  The transparent substrate (b2) is sandwiched between two cyclic olefin-based resin sheets (a1) cut to 18 cm × 25 cm, and is further sandwiched between polyimide films manufactured by Toray DuPont Co., Ltd. as a protective film. ) Press for 10 minutes at a temperature of 260 ° C., a degree of vacuum of 14 torr, and a pressure of 7.5 MPa using a vacuum press (J2008010MHPCV750 type). Thereafter, the protective film was peeled off, and as a result, a transparent glass cloth composite film was obtained. Let the obtained glass cloth composite film be a composite film (c2).

The thickness of the composite film (c2) was 120 μm, and the total light transmittance was 93%.
[Production Example 4]
Two cyclic olefin-based resin sheets (a1) cut into 18 cm × 25 cm are stacked, sandwiched between polyimide films manufactured by Toray DuPont Co., Ltd. as a protective film, and a vacuum press (J2008010MHPCV750 type) manufactured by Meiki Seisakusho Co., Ltd., with a temperature of 260 Pressing was performed at a temperature of 14 ° C., a vacuum of 14 torr, and a pressure of 7.5 MPa for 10 minutes. As a result, a transparent film was obtained. Let the obtained film be a film (c3).

The thickness of the film (c3) was 80 μm, and the total light transmittance was 95%.
[Example 1]
Using a vacuum deposition apparatus, silica (SiO ₂ ) as dielectric layer A and titania (TiO ₂ ) as dielectric layer B are alternately applied to both sides of the composite film (c1) at a deposition temperature of 100 ° C. A total of 40 layers were stacked in 20 layers. The film thickness for one layer was 120 to 180 nm and 70 to 120 nm, respectively. A cross composite film (a1) in which a near-infrared reflective film made of a dielectric multilayer film was laminated was obtained. This film is referred to as a laminated film (i). The evaluation of the near-infrared cutting ability, heat cracking resistance and punchability of the laminated film (i) is shown in the following table.

[Example 2]
In Example 1, laminated film (ii) was obtained like Example 1 except having used composite film (c2) instead of composite film (c1). The evaluation of the laminated film is shown in the table below.

[Comparative Example 1]
In Example 1, laminated film (iii) was obtained like Example 1 except having used film (c3) instead of composite film (c1). The evaluation of the laminated film is shown in the table below.

表１から、積層フィルムの透明基板として、ガラスクロスを複合させた透明基板を用いた実施例１、２は、近赤外線カット層の加熱クラック発生を抑制し、耐熱性が向上することが明らかになった。また、同時に打抜き時のクラック発生を防止することも明らかになった。

From Table 1, it is clear that Examples 1 and 2 using a transparent substrate combined with glass cloth as the transparent substrate of the laminated film suppress the occurrence of heating cracks in the near infrared cut layer and improve the heat resistance. became. At the same time, it has also been clarified that cracking at the time of punching is prevented.

  The near-infrared cut filter of the present invention is suitable as a visibility correction filter for a solid-state imaging device such as a CCD or CMOS.

Claims (6)

  (A) Dielectric layer A and a dielectric layer having a higher refractive index than that of dielectric layer A on at least one surface of a transparent substrate containing a cyclic olefin-based resin and (B) a glass filler A near-infrared cut filter comprising a near-infrared reflective film made of a dielectric multilayer film in which B is alternately laminated. The near-infrared cut filter according to claim 1, wherein the (A) cyclic olefin-based resin has a structural unit derived from a compound represented by the following formula (1).

(In the formula, R ^{1 to} R ⁴ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or other monovalent organic group, and any ^one of R ^{1 to} R ⁴ may be used. Two may be bonded to each other to form a monocyclic or polycyclic structure, and m and p each independently represent 0 or a positive integer.)   3. The polymer according to claim 1, wherein the (A) cyclic olefin-based resin is a hydrogenated polymer after ring-opening (co) polymerizing the compound represented by the formula (1). Near-infrared cut filter.   (B) The near-infrared cut filter according to any one of claims 1 to 3, wherein the glass filler is a glass cloth. The dielectric layer A is made of silica (SiO ₂ ), and the dielectric layer B is made of titania (Ti
The near-infrared cut filter according to claim 1, comprising O ₂ ).   (A) Dielectric layer A and a dielectric layer having a higher refractive index than that of dielectric layer A on at least one surface of a transparent substrate containing a cyclic olefin-based resin and (B) a glass filler A method for producing a near-infrared cut filter, comprising a step of forming a near-infrared reflective film comprising a dielectric multilayer film in which B is alternately laminated by a vacuum deposition method.