TW201837123A - Composition for solid-state imaging element and method for forming infrared-shielding film for solid-state imaging element - Google Patents

Abstract

The present invention is a composition for a solid-state imaging element including an inorganic compound, a polymer, an organic pigment, and a solvent, wherein the amine value of the polymer is 90 mg KOH/g to 200 mg KOH/g, the solvent includes a specific solvent having a solubility parameter of 8.8 to 12.0, the content of the specific solvent with respect to the entire amount of the composition for a solid-state imaging element is 40% by mass to 90% by mass, and the solubility of the organic pigment in the solvent at 20 DEG C and 0.1 MPa is 2% by mass or greater.

Description

Composition for solid-state imaging element and method for forming infrared shielding film for solid-state imaging element

The present invention relates to a composition for a solid-state imaging element and a method for forming an infrared shielding film for a solid-state imaging element.

Charge-Coupled Device (CCD) image sensors or Complementary metal oxide semiconductor (CMOS) image sensors are mounted in video cameras, digital cameras, mobile phones with camera functions, etc. Solid-state imaging element. The sensitivity of the photodiodes included in these solid-state imaging elements spans the visible light region to the infrared region. Therefore, a solid-state imaging device is provided with a filter for blocking infrared rays. By using the infrared cutoff filter, the sensitivity of the solid-state imaging element can be corrected in a manner close to the visual acuity of a human being.

The infrared blocking filter contains an organic pigment or an inorganic compound as an infrared shielding agent (see Japanese Patent Laid-Open No. 2013-137337 and Japanese Patent Laid-Open No. 2013-151675). The infrared cutoff filter is usually formed by coating a substrate with a composition containing an infrared cutoff agent. In the infrared cutoff filter, the coating film of the composition functions as a film that blocks infrared rays. [Prior Art Literature] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open No. 2013-137337 Patent Document 2: Japanese Patent Laid-Open No. 2013-151675

[Problems to be Solved by the Invention] The composition for a solid-state imaging element is required to form an optical filter having both good visible light transmittance and infrared shielding properties. In addition, the composition for a solid-state imaging element requires high dispersion stability or stability over time. In these insufficient cases, defects of the obtained optical filter (infrared shielding film) may be caused, or productivity may be reduced. In addition, it affects visible light transmittance or infrared shielding properties. Furthermore, there may be a case where a patterned infrared shielding film is formed by exposing and developing a coating film, but in this case, it is required that the composition for a solid-state imaging element to be used has good patternability.

This invention is made in view of the said situation, The objective is to provide the composition for solid-state imaging elements, and the formation method of the shielding film for solid-state imaging elements using the said composition for solid-state imaging elements It can form an optical filter for a solid-state imaging device that has high dispersion stability and stability over time, has few defects, and has both good visible light transmittance and infrared shielding properties. [Means for solving problems]

The invention completed to solve the above problem is a composition for a solid-state imaging device, which includes an inorganic compound, a polymer, an organic pigment, and a solvent, and the amine value of the polymer is 90 mgKOH / g or more and 200 mgKOH / g or less the vehicle comprises a solubility parameter of 8.8 (cal / cm ^{3) 1/2} or more and 12.0 (cal / cm ^{3) 1/2} or less specific vehicles, the particular vehicle with respect to the solid-state image pickup element overall composition The content of the organic pigment is 40% by mass or more and 90% by mass or less, and the solubility of the organic pigment in the solvent at 20 ° C and 0.1 MPa is 2% by mass or more.

Another invention completed to solve the above-mentioned problem is a method for forming an infrared shielding film for a solid-state imaging element, which includes a step of forming a coating film on one surface side of a substrate, and forming a solid-state imaging element using the composition for a solid-state imaging element. Mentioned coating film. [Effect of the invention]

According to the present invention, it is possible to provide a composition for a solid-state imaging element and a method for forming a shielding film for a solid-state imaging element using the composition for a solid-state imaging element. The composition for a solid-state imaging element can form dispersion stability and time. Optical filter for solid-state imaging device with high stability, few defects, and good visible light transmission and infrared shielding.

Hereinafter, a composition for a solid-state imaging element and a method for forming an infrared shielding film for a solid-state imaging element according to an embodiment of the present invention will be described in detail.

<Composition for solid-state imaging element> The composition for a solid-state imaging element (hereinafter, also simply referred to as a "composition") according to an embodiment of the present invention includes [A] an inorganic compound, [B] a polymer, and [C] an organic pigment. And [D] Solvent. [B] The polymer is a polymer having an amine value of 90 mgKOH / g or more and 200 mgKOH / g or less. [D] The solvent includes a specific solvent whose solubility parameter (hereinafter, also referred to as "SP value") is 8.8 (cal / cm ³ ) ^1/2 or more and 12.0 (cal / cm ³ ) ^1/2 or less (hereinafter, also referred to as "[D1] Solvent"). [D1] The content of the solvent with respect to the entire composition for the solid-state imaging element is 40% by mass or more and 90% by mass or less. The solubility of the [C] organic pigment in the [D] solvent at 20 ° C and 0.1 MPa is 2% by mass or more.

In this composition, by using a [B] polymer having a specific amine value, the dispersibility of the [A] inorganic compound is improved. Further, the dispersibility of the [A] inorganic compound can be improved by containing a predetermined amount of the [D1] solvent having a specific solubility parameter. When the dispersibility of the [A] compound is high, the visible light transmittance or infrared shielding property of the obtained optical filter also becomes good. In addition, by combining a highly soluble [C] organic pigment with a [D] solvent, the visible light transmittance, infrared shielding properties, and the like can be further improved. Therefore, according to this composition, an optical filter for a solid-state imaging device that has high dispersion stability and stability over time, has few defects, and has good visible light transmittance and infrared shielding properties can be formed.

The composition preferably further contains [E] a polymerizable compound, and further preferably contains [F] a polymerization initiator. The composition may further include other components. Hereinafter, each component is demonstrated in detail.

([A] Inorganic compound) [A] An inorganic compound is a component which functions as an infrared shielding agent. [A] The inorganic compound may be a so-called pigment. [A] The inorganic compound preferably has a maximum absorption wavelength in a range of a wavelength of 800 nm to 2,000 nm. [A] The inorganic compound is particulate, and is dispersed in the composition.

[A] The inorganic compound is preferably an oxide of a metal or a semimetal (such as silicon). [A] The inorganic compound is specifically preferably tungsten cesium oxide, quartz, magnetite, aluminum oxide, titanium dioxide, zirconia, spinel, or a combination thereof. These inorganic compounds may be used singly or in combination of two or more.

As [A] inorganic compound, among these, tungsten cesium oxide is preferable. Tungsten cesium oxide is an infrared shielding agent that has high absorption of infrared rays (especially infrared rays having a wavelength of about 800 nm to 1,200 nm) (that is, high shielding ability to infrared rays) and low absorption to visible light. Therefore, by using tungsten cesium oxide, it is possible to maintain good visible light transmittance of the obtained optical filter and improve infrared shielding properties.

Tungsten cesium oxide can be represented by the following formula (a), for example. Cs _x WO _y (a) In formula (A), 0.001 ≦ x ≦ 1.1. 2.2 ≦ y ≦ 3.0.

When x in the formula (a) is 0.001 or more, infrared rays can be sufficiently shielded. The lower limit of x is preferably 0.01, and more preferably 0.1. On the other hand, when x is 1.1 or less, generation of an impurity phase in tungsten cesium oxide can be more reliably avoided. The upper limit of x is preferably 1 and more preferably 0.5.

When y in the formula (a) is 2.2 or more, the chemical stability as a material can be further improved. The lower limit of y is preferably 2.5. On the other hand, when y is 3.0 or less, infrared rays can be sufficiently shielded.

Specific examples of tungsten cesium oxide represented by the formula (a) include Cs _0.33 WO ₃ and the like.

[A] The inorganic compound is preferably fine particles. The upper limit of the average particle diameter (D50) of the [A] inorganic compound is preferably 500 nm, more preferably 200 nm, still more preferably 50 nm, even more preferably 30 nm, and even more preferably 20 nm. When the average particle diameter is equal to or less than the upper limit, visible light transmittance can be further improved. On the other hand, the average particle diameter of the [A] inorganic compound is usually 1 nm or more and may be 10 nm or more for reasons such as ease of handling during production. The average particle diameter (D50) is a secondary particle diameter in the composition.

[A] An inorganic compound can also be synthesized by a known method, and can be obtained as a commercial product. For example, tungsten cesium oxide can also be obtained as a dispersion of tungsten cesium oxide particles such as "YMF-02" by Sumitomo Metal Mining Corporation.

The lower limit of the content of the [A] inorganic compound in the total solid content in the composition is preferably 1% by mass, more preferably 10% by mass, even more preferably 20% by mass, and even more preferably 30% by mass. %. On the other hand, the upper limit of the content is preferably 70% by mass, and more preferably 60% by mass. By setting the content of the [A] inorganic compound within the above range, the visible light transmittance and infrared shielding properties of the obtained optical filter can be more well-balanced. In addition, the dispersion stability or the stability over time of the composition can be made better. In addition, all solid components are all components other than [D] solvent.

([B] polymer) [B] polymer is a component which improves the dispersibility of [A] inorganic compounds and the like. [B] The polymer may include one polymer or a mixture of two or more polymers having the same or different amine values. A polymer having an amine value of 0 mgKOH / g is not included in the [B] polymer as a mixture of a plurality of polymers.

[B] The lower limit of the amine value of the polymer is 90 mgKOH / g, preferably 110 mgKOH / g, and more preferably 130 mgKOH / g. On the other hand, the upper limit of the amine value is 200 mgKOH / g. By using the polymer having the amine value, the dispersibility of the [A] inorganic compound is improved, and the visible light transmittance and infrared shielding properties of the obtained optical filter can be further improved. The "amine value" is the number of mg of KOH equivalent to HCl equivalent to 1 g of the solid content of the polymer. When the [B] polymer is a mixture of a plurality of polymers having different amine values, the amine value of the [B] polymer is a weighted average.

[B] The polymer is preferably a block copolymer. The block copolymer is preferably a block copolymer having an A block containing a functional group containing a nitrogen atom and a B block having a solvent affinity. The nitrogen atom-containing functional group of the A block shows good adsorptivity to the [A] inorganic compound. Therefore, by using a block copolymer having an A block and a B block, the dispersibility of the [A] inorganic compound can be further improved.

The A block preferably has a structural unit represented by the following formula (1), for example.

[Chemical 1]

In formula (1), X is a divalent linking group. R ¹ is a hydrogen atom or a methyl group. R ² and R ³ are each independently a hydrogen atom, or a chain-like or cyclic hydrocarbon group which may have a substituent, or R ² and R ³ are bonded to each other and form a ring structure together with these bonded nitrogen atoms.

Examples of the X include a methylene group, an alkylene group having 2 to 10 carbon atoms, an arylene group, a group represented by -CONH-R ⁷ -(*), and -COO-R ⁸ -(*). Expressed bases and so on. R ⁷ and R ⁸ are each independently a methylene group, an alkylene group having 2 to 10 carbon atoms, or an alkyleneoxy group 2 to 10 carbon atoms. (*) Indicates a bonding site with N. X is preferably a group represented by -COO-R ^8- , and R ^{8 is} preferably an alkylene group having 2 to 6 carbon atoms.

R ² and R ^{3 are} preferably a chain hydrocarbon group, more preferably a chain hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a methyl group, an ethyl group, and a propyl group.

Examples of the single body that provides the structural unit represented by the formula (1) include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and (methyl) ) Dimethylaminopropyl acrylate, diethylaminopropyl (meth) acrylate, and the like.

The A block may include a structural unit other than the structural unit represented by the formula (1). The content ratio of the A block in the block copolymer is preferably, for example, 30% by mass or more and 70% by mass or less.

The B block preferably has a structural unit represented by the following formula (2), for example.

[Chemical 2]

In formula (2), R ^{4 is} each independently an alkylene group having 2 to 4 carbon atoms. R ⁵ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ⁶ is a hydrogen atom or a methyl group. n is an integer from 1 to 150.

R ^{4 is} preferably ethylene or methyl. R ^{5 is} preferably methyl, ethyl, propyl, or butyl. The upper limit of n is preferably 20, more preferably 10, and even more preferably 5.

Examples of the singular body that provides the structural unit represented by the formula (2) include polyethylene glycol (n = 1 to 5) methyl ether (meth) acrylate, and polyethylene glycol (n = 1 to 5). 5) Diethyl ether (meth) acrylate, polyethylene glycol (n = 1 ~ 5) propyl ether (meth) acrylate, polypropylene glycol (n = 1 ~ 5) methyl ether (meth) acrylate, polypropylene glycol (N = 1 ~ 5) diethyl ether (meth) acrylate, polypropylene glycol (n = 1 ~ 5) propyl ether (meth) acrylate, etc.

The B block may include a structural unit other than the structural unit represented by the formula (2). As another structural unit which a B block can contain, the structural unit derived from a (meth) acrylate is mentioned. Specifically, as a singular body which provides another structural unit, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, phenyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like.

The content ratio of the B block in the block copolymer is preferably, for example, 30% by mass or more and 70% by mass or less.

The lower limit of the average molecular weight of the [B] polymer is, for example, 3,000, and preferably 6,000. On the other hand, the upper limit is, for example, 30,000, and preferably 20,000.

The block copolymer can be synthesized by a previously known method. In addition, a commercially available product can also be used for a block copolymer and other [B] polymers. [B] The polymer may be a dispersant that coats at least a part of the surface of the [A] inorganic compound in the composition.

The lower limit of the content of [B] the polymer is preferably 5 parts by mass, more preferably 10 parts by mass, and even more preferably 20 parts by mass based on 100 parts by mass of the [A] inorganic compound. On the other hand, the upper limit of the content is preferably 200 parts by mass, more preferably 100 parts by mass, and even more preferably 60 parts by mass.

([C] organic pigment) [C] organic pigment is a component which functions as an infrared shielding agent with [A] an inorganic compound. By using the [A] inorganic compound and the [C] organic pigment in combination, excellent visible light transmittance and infrared shielding properties can be exhibited. [C] The organic pigment is dissolved in the [D] solvent.

Examples of the [C] organic pigment include organic dyes and organic pigments, and organic dyes are preferred. By using an organic dye, the solubility of the [D] solvent is improved, and the generation of agglomerated foreign matter can be further suppressed.

The solubility of the [C] organic pigment in the [D] solvent at 20 ° C and 0.1 MPa is 2% by mass or more. Therefore, the composition can obtain an optical filter having good characteristics of high solubility of the [C] organic pigment, improved dispersion stability or stability over time, and further reduced defects. The solubility refers to the concentration (mass%) of the [C] organic pigment in the solution in which the maximum amount of the [C] organic pigment is dissolved in the [D] solvent, that is, the saturated solution. In the case where the [D] solvent is a mixed solvent, the concentration of the [C] organic pigment in a saturated solution using the mixed solvent as a solvent. The solubility of the [C] organic pigment can be achieved by a combination of the [C] organic pigment and a [D] solvent. The lower limit of the solubility is not particularly limited, and may be, for example, 50% by mass.

[C] The organic pigment preferably has a maximum absorption wavelength in a range of 600 nm to 1,000 nm. The lower limit of the maximum absorption wavelength is more preferably 650 nm. On the other hand, the upper limit is preferably 900 nm, and more preferably 850 nm. By using the [C] organic pigment having the above-mentioned maximum absorption wavelength, the visible light transmittance or infrared shielding properties of the obtained optical filter can be made better.

As the [C] organic pigment, a conventionally known organic pigment can be appropriately selected and used within a range satisfying the solubility. As the [C] organic pigment, a diimine compound, a squarium ylide compound, a cyanine compound, a phthalocyanine compound, a naphthalocyanine compound, a quartrenene compound, an ammonium compound, an imine compound, and an azo compound can be used , Anthraquinone compound, porphyrin compound, pyrrolopyrrole compound, oxacyanine compound, ketonium compound, hexamethylene porphyrin compound, or a combination of these. [C] The organic pigment preferably contains a phthalocyanine compound. The phthalocyanine compound is excellent in color, heat resistance, light resistance, and the like.

[C] The organic pigment may be used alone or in combination of two or more. The composition preferably contains two or more [C] organic pigments. Furthermore, it may be more preferable to contain three or more [C] organic pigments. By using a plurality of [C] organic pigments in combination, the visible light transmittance or infrared shielding properties of the obtained optical filter can be made better. On the other hand, when a plurality of organic pigments are used, dispersion stability, stability over time, and the like may decrease. However, according to this composition, even if a plurality of organic pigments are used, good dispersion stability or stability over time can be exhibited. The upper limit of the number of types of the [C] organic pigment used is not particularly limited, and may be, for example, 10 types, 5 types, or 3 types.

The lower limit of the content of the [C] organic pigment in the total solid content in the composition is preferably 0.1% by mass, more preferably 0.5% by mass, and even more preferably 1% by mass. On the other hand, the upper limit of the content is preferably 30% by mass, more preferably 15% by mass, and even more preferably 10% by mass. By setting the content of the [C] organic pigment within the above range, the visible light transmittance and infrared shielding properties of the obtained optical filter are more well-balanced.

([D] Solvent) [D] Solvent is a component that functions as a dispersion medium for the [A] inorganic compound and dissolves the [C] organic pigment and the like.

[D] Solvent includes [D1] Solvent. [D1] The solvent is a solvent having an SP value of 8.8 (cal / cm ³ ) ^1/2 or more and 12.0 (cal / cm ³ ) ^1/2 or less. The lower limit of the SP value is preferably 9.5 (cal / cm ³ ) ^1/2 . On the other hand, the upper limit is preferably 11.0 (cal / cm ³ ) ^1/2 , and more preferably 10.5 (cal / cm ³ ) ^1/2 . By using the [D1] solvent having an SP value in the specific range, the dispersibility of the [A] inorganic compound or the solubility of the [C] organic pigment can be improved. Here, the SP value is a value obtained by the following Feder formula described in RF Feders, Polymer Engineering and Science (RFFedors, Polym. Eng. Sci.,) 14,147 (1974). Feder's formula: SP value (δ) = (E _v / v) _1/2 = (ΣΔe _i / ΣΔv _i ) _1/2 E _v : evaporation energy v: mole volume Δe _i : atom of each component or Evaporation energy Δv _{i of} atomic group: Molar volume of each atom or atomic group

Examples of the [D1] solvent include n-propanol (SP value: 11.8), 1,2,5,6-tetrahydrobenzyl alcohol (SP value: 11.3), and diethylene glycol ether (SP value: 10.9). , 3-methoxybutanol (SP value: 10.9), glycerol triacetate (SP value: 10.2), propylene glycol monomethyl ether (SP value: 10.2), cyclopentanone (SP value: 10.0), γ- Butyrolactone (SP value: 9.9), Cyclohexanone (SP value: 9.9), Propylene glycol-n-propyl ether (SP value: 9.8), Propylene glycol-n-butyl ether (SP value: 9.7), Dipropylene glycol methyl ether (SP Value: 9.7), 1,4-butanediol diacetate (SP value: 9.6), 3-methoxybutyl acetate (SP value: 8.7), propylene glycol diacetate (SP value: 9.6) ), Ethyl acetate lactate (SP value: 9.6), ε-caprolactone (SP value: 9.6), 1,3-butanediol diacetate (SP value: 9.5), dipropylene glycol-n-propyl Ether (SP value: 9.5), 1,6-hexanediol diacetate (SP value: 9.5), dipropylene glycol-n-butyl ether (SP value: 9.4), tripropylene glycol methyl ether (SP value: 9.4), Tripropylene glycol-n-butyl ether (SP value: 9.3), cyclohexanol acetate (SP value: 9.2), diethylene glycol ether acetate (SP value: 9.0), ethylene glycol methyl ether acetate ( SP value: 9.0), diethylene glycol monobutyl ether acetate (SP value: 8.9), Ethylene glycol monobutyl ether acetate (SP value: 8.9), toluene (SP value: 8.9), methyl acetate (SP value: 8.8), and the like. The unit of the SP value ((cal / cm ³ ) ^1/2 ) is appropriately omitted. [D1] The solvent may be used singly or in combination of two or more kinds.

[D1] The lower limit of the content of the solvent with respect to the entire composition is 40% by mass, preferably 50% by mass, more preferably 60% by mass, and even more preferably 65% by mass. When the content of the [D1] solvent is equal to or more than the lower limit, the dispersibility of the [A] inorganic compound or the solubility of the [C] organic pigment is further improved. On the other hand, the upper limit of the content of the [D1] solvent is 90% by mass, preferably 80% by mass, and more preferably 75% by mass. By setting the content of the [D1] solvent below the upper limit, a sufficient amount of other components can be formulated, that is, by setting the content of the [D1] solvent to the range, the dispersion stability of the composition can be improved With time-dependent stability, this composition can form an optical filter for a solid-state imaging device that has fewer defects and has good visible light transmission and infrared shielding properties.

The [D] solvent may include a [D2] solvent other than the [D1] solvent. [D2] The solvent is a solvent whose SP value is less than 8.8 (cal / cm ³ ) ^1/2 or more than 12.0 (cal / cm ³ ) ^1/2 . Examples of the [D2] solvent include (poly) alkanediol monoalkyl ethers and (cyclo) alkanes whose SP value is less than 8.8 (cal / cm ³ ) ^1/2 or more than 12.0 (cal / cm ³ ) ^1/2 . Base alcohols, keto alcohol (poly) alkanediol monoalkyl ether acetates, ketones, diacetates, carboxylic acid esters, lactams, aromatic hydrocarbons, and the like. For example, examples of the (poly) alkanediol monoalkyl ether having an SP value of less than 8.8 (cal / cm ³ ) ^1/2 include propylene glycol monomethyl ether acetate (SP value: 8.7).

The SP value of the [D2] solvent is preferably less than 8.8 (cal / cm ³ ) ^1/2 . The lower limit of the SP value of the [D2] solvent is preferably 7 (cal / cm ³ ) ^1/20 , more preferably 8 (cal / cm ³ ) ^1/2 , and even more preferably 8.5 (cal / cm ³ ) ^1/2 .

The lower limit of the content of the [D1] solvent in the [D] solvent is preferably 50% by mass, more preferably 70% by mass, even more preferably 80% by mass, and even more preferably 90% by mass. The [D] solvent may substantially include only the [D1] solvent. By setting the content of the [D1] solvent in the [D] solvent to be above the lower limit, the dispersibility of the [A] inorganic compound or the solubility of the [C] organic pigment is further improved, and the effects of the present invention are more fully obtained. Play.

[D] The solvent preferably contains a solvent having a ring structure. By using a solvent having a cyclic structure, the solubility or dispersibility becomes better. The solvent having a ring structure may be a [D1] solvent or a [D2] solvent, but a [D1] solvent is preferred. The cyclic structure may be a carbocyclic ring or a heterocyclic ring. In addition, the cyclic structure may be polycyclic or monocyclic. In addition, the cyclic structure may be an aromatic ring or an aliphatic ring.

As a solvent having a cyclic structure, cyclic ketones, cyclic ethers, lactones (γ-butyrolactone, ε-caprolactone, etc.), lactam, aromatic hydrocarbons (toluene, etc.), and these are preferable. The combination. Among these, a cyclic ketone, a lactone and an aromatic hydrocarbon are preferable, and a cyclic ketone and a lactone are more preferable.

Examples of the cyclic ketone include cyclobutanone, cyclopentanone, cyclohexanone, cycloheptanone, and cyclooctanone. Among these, cyclopentanone, cyclohexanone and cycloheptanone are preferred, and cyclopentanone and cyclohexanone are more preferred.

Examples of the cyclic ether include tetrahydrofuran and tetrahydropyran.

Examples of the lactone include γ-butyrolactone and ε-caprolactone, and γ-butyrolactone is preferred.

Examples of lactam include pent-4-lactam, 5-methyl-2-pyrrolidone, hex-6-lactam, 6-caprolactam, and the like.

The lower limit of the content of the solvent having a cyclic structure in the [D] solvent is preferably 50% by mass, more preferably 70% by mass, even more preferably 80% by mass, and even more preferably 90% by mass. [D] The solvent may substantially include only a solvent having a cyclic structure. By setting the content of the solvent having a cyclic structure in the [D] solvent to be above the lower limit, the dispersibility of the [A] inorganic compound or the solubility of the [C] organic pigment is further improved, and the effect of the present invention is more sufficient. The ground is brought into play.

The lower limit of the solid content concentration (the total concentration of each component other than the [D] solvent) in the composition is preferably 5% by mass, and more preferably 10% by mass. On the other hand, the upper limit of the solid content concentration is preferably 50% by mass, and more preferably 40% by mass. By setting the solid content concentration within the above range, dispersibility, stability, coatability, and the like become better.

([E] Polymerizable Compound) When the composition contains a [E] polymerizable compound, it can exhibit good curability and good heat resistance of the obtained optical filter. The [E] polymerizable compound refers to a compound having two or more polymerizable groups. Examples of the polymerizable group include an ethylenically unsaturated group, an ethylene oxide group, an oxetanyl group, and an N-alkoxymethylamino group. [E] The polymerizable compound may be a polymer or a singular body, but a singular body is preferred. [E] The polymerizable compound is preferably a compound having two or more (meth) acrylfluorenyl groups and a compound having two or more N-alkoxymethylamino groups, and more preferably two or more (Meth) acrylfluorenyl compounds. [E] The polymerizable compound may be used singly or in combination of two or more kinds.

Examples of the compound having two or more (meth) acrylfluorenyl groups include polyfunctional (meth) acrylates, which are reactants of an aliphatic polyhydroxy compound and (meth) acrylic acid, and modified with caprolactone. Polyfunctional (meth) acrylate, polyfunctional (meth) acrylate modified by alkylene oxide, polyfunctional amine group as a reactant of hydroxyl (meth) acrylate and polyfunctional isocyanate, etc. Polyfunctional (meth) acrylates having a carboxyl group, such as formate (meth) acrylate, a reactant of a (meth) acrylate having a hydroxyl group and an acid anhydride, and the like.

Here, examples of the aliphatic polyhydroxy compound include divalent aliphatic polyhydroxy compounds such as ethylene glycol, propylene glycol, polyethylene glycol, and polypropylene glycol, or glycerol, trimethylolpropane, pentaerythritol, and Trivalent or higher aliphatic polyhydroxy compounds such as pentaerythritol. Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, and diamine. Pentaerythritol penta (meth) acrylate, glycerol dimethacrylate and the like. Examples of the polyfunctional isocyanate include toluene diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, isophorone diisocyanate, and the like. Examples of the acid anhydride include dibasic anhydrides such as succinic anhydride, maleic anhydride, glutaric anhydride, itaconic anhydride, phthalic anhydride, and hexahydrophthalic anhydride, or pyromellitic dianhydride, Tetracarboxylic dianhydrides such as biphenyltetracarboxylic dianhydride and benzophenone tetracarboxylic dianhydride.

Specific examples of the compound having two or more (meth) acrylfluorenyl groups include, for example, ω-carboxy polycaprolactone mono (meth) acrylate, ethylene glycol (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate Ester, polypropylene glycol di (meth) acrylate, bisphenoxyethanol, di (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, 2-hydroxy-3- (formaldehyde) ) Acryloxypropyl methacrylate, 2- (2'-vinyloxyethoxy) ethyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri ( (Meth) acrylates, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tris (2- (meth) acryloxyethyl) Phosphate ester, ethylene oxide modified dipentaerythritol hexaacrylate, succinic acid modified pentaerythritol triacrylate, urethane (meth) acrylate compound, and the like.

Among compounds having two or more (meth) acrylfluorenyl groups, polyfunctional (meth) acrylates are preferred, and polyfunctionals having three or more (meth) acrylfluorene groups (Meth) acrylate. Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferable.

Examples of the compound having two or more N-alkoxymethylamino groups include compounds having a melamine structure, a benzoguanamine structure, and a urea structure. Specific examples of the compound having two or more N-alkoxymethylamino groups include N, N, N ', N', N '', N ''-hexa (alkoxymethyl) Melamine, N, N, N ', N'-tetrakis (alkoxymethyl) benzoguanamine, N, N, N', N'-tetrakis (alkoxymethyl) acetylene urea and the like.

The lower limit of the content of the [E] polymerizable compound in the total solid content of the composition is preferably 5 parts by mass, more preferably 10 parts by mass, and even more preferably 20 parts by mass. On the other hand, the upper limit of the content is preferably 60% by mass, and more preferably 50% by mass.

([F] Polymerization Initiator) [F] The polymerization initiator is a component that starts the polymerization reaction of the [E] polymerizable compound. Examples of the [F] polymerization initiator include a photopolymerization initiator and a thermal polymerization initiator, and a photopolymerization initiator is preferred. This makes it possible to impart sensitivity (radiation sensitivity) to the composition. The photopolymerization initiator refers to a compound that generates an active species that initiates polymerization of the [E] polymerizable compound upon exposure to radiation such as visible light, ultraviolet rays, far ultraviolet rays, electron beams, and X-rays. [F] The polymerization initiator may be used singly or in combination of two or more.

Examples of the [F] polymerization initiator include thioxanthone-based compounds, acetophenone-based compounds, biimidazole-based compounds, triazine-based compounds, O-fluorenyl oxime-based compounds, onium salt-based compounds, and benzoin-based compounds. Compounds, benzophenone-based compounds, α-diketone-based compounds, polynuclear quinone-based compounds, diazo-based compounds, ammonium sulfonate-based compounds, onium salt-based compounds, and the like. Among these, a thioxanthone-based compound, an acetophenone-based compound, a biimidazole-based compound, a triazine-based compound, or an O-fluorenyl oxime-based compound is preferred, and an O-fluorenyl oxime-based compound is more preferred.

Examples of thioxanthone-based compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4 -Dichlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and the like.

Examples of the acetophenone-based compound include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinylpropane-1-one and 2-benzyl-2-dimethyl Aminoamino-1- (4-morpholinylphenyl) butane-1-one, 2- (4-methylbenzyl) -2- (dimethylamino) -1- (4-morpholine Phenyl) butane-1-one and the like.

Examples of the biimidazole-based compound include 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole and 2,2' -Bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis (2,4,6-trichloro Phenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-biimidazole and the like.

When a biimidazole-based compound is used, a hydrogen donor is preferably used in combination in terms of improving sensitivity. The "hydrogen donor" as used herein means a compound capable of supplying a hydrogen atom to a radical generated from a biimidazole-based compound by exposure. Examples of the hydrogen donor include thiol-based hydrogen donors such as 2-mercaptobenzothiazole and 2-mercaptobenzoxazole; 4,4'-bis (dimethylamino) benzophenone; An amine hydrogen donor such as 4'-bis (diethylamino) benzophenone.

Examples of the triazine-based compound include compounds described in paragraphs [0063] to [0065] of Japanese Patent Laid-Open No. 57-6096 and Japanese Patent Laid-Open No. 2003-238898.

Examples of the O-fluorenyl oxime-based compound include 1,2-octanedione-1- [4- (phenylthio) phenyl] -2- (O-benzylidene oxime), and ethyl ketone-1 -[9-ethyl-6- (2-methylbenzylidene) -9H-carbazol-3-yl] -1- (O-ethylamidoxime), ethyl ketone-1- [9-ethyl -6- (2-methyl-4-tetrahydrofurylmethoxybenzyl) -9H-carbazol-3-yl] -1- (O-ethylamidoxime), ethyl ketone-1- [ 9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolyl) methoxybenzyl} -9H-carbazole-3 -Yl] -1- (O-acetylamoxime) and the like. As commercially available products of O-fluorenyl oxime-based compounds, NCI-831, NCI-930 (the above are manufactured by ADEKA), OXE-03, OXE-04 (the above are BASF ( BASF).

When a photopolymerization initiator is used, a sensitizer may be used in combination. Examples of the sensitizer include 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone, and 4-bis Ethylaminoacetophenone, 4-dimethylaminophenylacetone, ethyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,5- Bis (4-diethylaminobenzylidene) cyclohexanone, 7-diethylamino-3- (4-diethylaminobenzyl) coumarin, 4- (diethyl Amine) chalcone and the like.

The lower limit of the content of the [F] polymerization initiator is preferably 1 part by mass, and more preferably 5 parts by mass, relative to 100 parts by mass of the [E] polymerizable compound. On the other hand, the upper limit of the content is preferably 100 parts by mass, and more preferably 40 parts by mass.

(Binder Resin) The composition may further contain a binder resin. Furthermore, the [B] polymer is not contained in the binder resin. Although it does not specifically limit as a binder resin, The resin which has an acidic functional group, such as a carboxyl group and a phenolic hydroxyl group, is preferable. Among these, a polymer having a carboxyl group (hereinafter, also referred to as a “carboxyl-containing polymer”) is preferred. Examples of the carboxyl group-containing polymer include an ethylenically unsaturated monomer having one or more carboxyl groups (hereinafter, also referred to as "unsaturated monomer (1)") and other copolymerizable ethylenically unsaturated monomers. A copolymer of a quantitative body (hereinafter, also referred to as "unsaturated monobasic body (2)").

Examples of the unsaturated monomer (1) include (meth) acrylic acid, maleic acid, maleic anhydride, succinate mono [2- (meth) acryloxyethyl] ester, and ω -Carboxy polycaprolactone mono (meth) acrylate, p-vinylbenzoic acid, and the like.

Examples of the unsaturated monomer (2) include N-substituted maleimide, styrene, α, such as N-phenylmaleimide and N-cyclohexylmaleimide. -Methylstyrene, p-hydroxystyrene, p-hydroxy-α-methylstyrene, p-vinyl benzyl glycidyl ether, aromatic vinyl compounds such as fluorene, methyl (meth) acrylate, (meth) N-butyl acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, allyl (meth) acrylate, benzyl (meth) acrylate, polyethylene glycol ( Polymerization degree 2 ~ 10) methyl ether (meth) acrylate, polypropylene glycol (polymerization degree 2 ~ 10) methyl ether (meth) acrylate, polyethylene glycol (polymerization degree 2 ~ 10) mono (meth) acrylic acid Ester, polypropylene glycol (polymerization degree 2 ~ 10) mono (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decane- 8-yl (meth) acrylate, dicyclopentenyl (meth) acrylate, glycerol mono (meth) acrylate, 4-hydroxyphenyl (meth) acrylate, ethylene oxide of p-cumylphenol Modified (meth) acrylate, (meth) Glycidyl enoate, 3,4-epoxycyclohexyl methyl (meth) acrylate, 3-[(meth) acryloxymethyl] oxetane, 3-[(methyl) (Meth) acrylic acid esters such as propylene methyloxy] -3-ethyloxetane, cyclohexyl vinyl ether, isobornyl vinyl ether, tricyclo [5.2.1.0 ^2,6 ] decane Vinyl ethers such as -8-yl vinyl ether, pentacyclopentadecyl vinyl ether, 3- (vinyloxymethyl) -3-ethyloxetane, polystyrene, poly (methyl ) Methyl acrylate, poly (n-butyl) methacrylate, and polysiloxane are equal to macromonomers having a mono (meth) acrylfluorene group at the end of a polymer molecular chain, and the like.

In addition, as the binder resin, a carboxyl group-containing polymer having a polymerizable unsaturated bond such as a (meth) acrylfluorene group in a side chain can also be used. In addition, polysiloxane and the like can also be used as a binder resin.

(Additives) This composition may contain various additives as needed.

Examples of the additives include a surfactant, an adhesion promoter, an antioxidant, an ultraviolet absorber, an anti-agglomerating agent, a residue improving agent, and a developing property improving agent.

Examples of the surfactant include a fluorine surfactant, a silicone surfactant, and the like. The content of the surfactant in the total solid content of the composition can be, for example, 0.01% by mass or more and 5% by mass or less.

Examples of the adhesion promoter include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (2-methoxyethoxy) silane, and N- (2-aminoethyl) -3. -Aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-shrink Glyceryloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-chloropropane Methylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and the like.

Examples of the antioxidant include 2,2-thiobis (4-methyl-6-tert-butylphenol), 2,6-di-tert-butylphenol, and pentaerythritol tetra [3- (3,5 -Di-third-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2- [3- (3-third-butyl-4-hydroxy-5-methylphenyl)- Propyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxa-spiro [5.5] undecane, thiodiethylenebis [3- (3,5- Di-third butyl-4-hydroxyphenyl) propionate] and the like. The content of the antioxidant in the total solid content of the composition may be, for example, 0.01% by mass or more and 5% by mass or less.

Examples of the ultraviolet absorber include 2- (3-thirdbutyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, and alkoxybenzophenones.

Examples of the anticoagulant include sodium polyacrylate.

Examples of the residue improving agent include malonic acid, adipic acid, itaconic acid, citraconic acid, fumaric acid, mesaconic acid, 2-aminoethanol, 3-amino-1-propanol, 5-amino-1-pentanol, 3-amino-1,2-propanediol, 2-amino-1,3-propanediol, 4-amino-1,2-butanediol, and the like.

Examples of the developability improving agent include: [2- (meth) acryloxyethyl] succinate, [2- (meth) acryloxyethyl] phthalate, and ω -Carboxy polycaprolactone mono (meth) acrylate and the like.

(Preparation method) There is no restriction | limiting in particular as a preparation method of this composition, It can prepare by mixing each component. For example, the following method can be adopted: first, a dispersion liquid containing [A] an inorganic compound, a [B] polymer, and a [D] solvent is prepared, and [C] an organic pigment or other component is added to the dispersion liquid and mixed. In this case, a [D] solvent may be further added. The dispersion or the composition may be subjected to a filtration treatment as necessary to remove aggregates.

<Method for forming infrared shielding film for solid-state imaging element> A method for forming an infrared shielding film for a solid-state imaging element according to an embodiment of the present invention includes a step (step 1) of forming a coating film on one surface side of a substrate, and using the solid The composition for an imaging element forms the coating film.

The forming method preferably further includes a step of irradiating at least a part of the coating film with radiation (step 2), and a step of developing the coating film with radiation (step 3).

According to this formation method, an optical filter for a solid-state imaging device having both a small defect and a good visible light transmittance and an infrared shielding property can be formed by using a composition having high dispersion stability and stability over time. In addition, when the forming method includes steps 2 and 3, it has good patternability.

(Step 1) In step 1, using this composition, a coating film is formed on one surface side of a substrate (support). Examples of the substrate include a glass substrate and a synthetic resin substrate. The shape of the substrate is not limited to a plate shape. When an infrared shielding film is incorporated in a solid-state imaging element described later, a transparent substrate, a microlens, a color filter, and the like, which are constituent elements of the solid-state imaging element, correspond to the substrate.

The formation of a coating film can usually be performed by coating this composition. The coating can be performed by a suitable coating method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slot die coating method (slit coating method), or a bar coating method.

After coating, a pre-baking is performed to evaporate the solvent, thereby forming a coating film. Conditions for the pre-baking heating and drying are, for example, about 70 ° C. to 110 ° C., and about 1 minute to 10 minutes.

(Step 2) In step 2, at least a part of the coating film is irradiated with radiation. Examples of the radiation light source used in the exposure of the coating film include xenon lamps, halogen lamps, tungsten lamps, high-pressure mercury lamps, ultrahigh-pressure mercury lamps, metal halogen lamps, medium-pressure mercury lamps, and low-pressure mercury lamps, or argon ion laser , Yttrium aluminum garnet (YAG) laser, XeCl 凖 molecular laser, nitrogen laser and other laser light sources. As an exposure light source, an ultraviolet light emitting diode (LED) can also be used. The radiation having a wavelength in the range of 190 nm to 450 nm is preferred. The radiation exposure amount is usually about 10 J / m ² or more and about 50,000 J / m ² or less.

(Step 3) In step 3, the coating film after radiation irradiation is developed. The developer is usually an alkaline developer or an organic solvent developer. Furthermore, after development, it is usually washed with water.

The developing solution is usually an alkaline developing solution. Examples of the alkaline developer include sodium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, choline, and 1,8-diazabicyclo- [5.4.0]- 7-undecene, 1,5-diazabicyclo- [4.3.0] -5-nonene and other aqueous solutions. An appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, or the like may be added to the alkaline developer.

As the organic solvent developer, acetone, methyl ethyl ketone, 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3 -Ketones such as hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate , Isoamyl acetate, propyl formate, butyl formate, isobutyl formate, pentyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl butenoate, ethyl butenoate , Methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate , Methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, phenyl methyl acetate, benzyl formate, phenyl formate Esters such as ethyl ester, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, 2-phenylethyl acetate and the like.

As the development processing method, a spray development method, a spray development method, a dip development method, a puddle development method, and the like can be applied. The developing conditions are about 5 seconds to 300 seconds at normal temperature.

The non-exposed portion of the coating film is dissolved and removed by the development. Thereafter, by performing post-baking as necessary, an infrared shielding film patterned into a predetermined shape can be obtained. The post-baking conditions are usually about 180 ° C. to 280 ° C., about 1 minute to about 60 minutes.

When the composition does not contain a [E] polymerizable compound and a [F] polymerization initiator, unlike the formation method described above, curing treatment such as exposure may not be performed. In addition, the development process may not be performed, and in this case, an unpatterned infrared shielding film may be formed.

The lower limit of the average film thickness of the infrared shielding film for a solid-state imaging element formed as described above is usually 0.5 μm, and preferably 1 μm. On the other hand, the upper limit of the average film thickness is usually 5 μm, and preferably 3 μm. When the average film thickness of the infrared shielding film is within the above range, the balance between the visible light transmittance and the infrared shielding property becomes better.

The infrared shielding film is preferably incorporated into a solid-state imaging element as a constituent member. In this case, the infrared shielding film functions as an optical filter (infrared cut filter) in the form of a single body. Since an infrared shielding film is incorporated in the solid-state imaging device, a large process margin and the like can be obtained. When the infrared shielding film is incorporated in the solid-state imaging element, the infrared shielding film may be disposed on the outer surface side of the microlens of the solid-state imaging element, between the microlens and the color filter, the color filter and the photoelectric Wait between diodes. The infrared shielding film is preferably laminated between a microlens and a color filter or between a color filter and a photodiode.

The optical filter may be one having an infrared shielding film on a surface area layer of a transparent substrate. As the transparent substrate, glass, transparent resin, or the like can be used. Examples of the transparent resin include polycarbonate, polyester, aromatic polyimide, polyimide, imine, and polyimide. The optical filter is also preferably used as an infrared cut filter in a solid-state imaging element.

Solid-state imaging device with infrared shielding film (optical filter) for digital still camera, mobile phone camera, digital video camera, personal computer (PC) camera, surveillance camera, automotive camera, portable information terminal , Computers, video games, medical equipment, etc. [Example]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. In addition, the characteristics of the polymer obtained by the synthesis example were measured by the following method.

[Weight average molecular weight (Mw), number average molecular weight (Mn), and dispersion (Mw / Mn)] Mw and Mn of the polymer were obtained using Tosoh's Gel Permeation Chromatography (GPC) column (2 G2000HXL, 1 G3000HXL, 1 G4000HXL) were measured by gel permeation chromatography (GPC) under the following analysis conditions. The degree of dispersion (Mw / Mn) is calculated from the measurement results of Mw and Mn. (Analysis conditions) Dissolution solvent: Tetrahydrofuran Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass Sample injection volume: 100 μL Column temperature: 40 ° C Detector: Differential refractometer Standard substance: Monodisperse polystyrene

<Synthesis Example 1> (Synthesis of Organic Pigment (C-1)) The method described in paragraphs [0020] to [0025] (Example 1) of Japanese Patent Laid-Open No. 05-25177 was used to synthesize as the following formula: An organic pigment (C-1) of a phthalocyanine compound.

[Chemical 3]

<Synthesis Example 2> (Synthesis of Organic Pigment (C-2)) Using the method described in paragraph [0075] (Example 4) of Japanese Patent Laid-Open No. 2016-204536, a phthalate represented by the following formula was synthesized Organic pigment of cyanine compound (C-2).

[Chemical 4]

<Synthesis Example 3> (Synthesis of Organic Colorant (C-3)) Using the method described in Japanese Patent Laid-Open No. 1-228960, an organic colorant (C -3).

[Chemical 5]

<Synthesis Example 4> (Synthesis of organic dye (C-4)) An organic dye (C-4) as a phthalocyanine compound represented by the following formula was synthesized using a method described in Japanese Patent Laid-Open No. 2-138382. .

[Chemical 6]

In addition, the organic pigments used are as follows. · Organic pigment (C-5): "FDN-002" (phthalocyanine compound) of Yamada Chemical Industry Co., Ltd. · Organic pigment (C-6): "FDR-004" (phthalocyanine compound) of Yamada Chemical Industry Co., Ltd. · Organic Pigment (C-7): "FDN-001" (phthalocyanine compound) by Yamada Chemical Industry Co., Ltd.

<Synthesis Example 5 to Synthesis Example 7> (Synthesis of Polymer (B-1) to Polymer (B-3)) Using the method described in the literature (Macromolecules 1992, 25, p5907-5913), Synthesis of polymer (B-1) to polymer (B-3) with monomer composition ratio (mass ratio) shown in Table 1 below. A polymer having a diblock structure including a block of a monomer (DAMA) having an adsorbing group for an inorganic compound as a pigment and a block of other components can be obtained. Furthermore, the solution after the reaction was quenched with methanol, and the obtained reaction solution was washed in a 7% by mass sodium bicarbonate aqueous solution, followed by water. Thereafter, by replacing the solvent with Propylene Glycol Monomethyl Ether Acetate (PGMEA), the polymer solution described in Table 1 below was obtained at a yield of 80% to 82% by mass. Table 1 shows the amine value, Mw, Mw / Mn, and solid content of each polymer obtained. In the table, DAMA indicates dimethylaminoethyl methacrylate, EHMA indicates 2-ethylhexyl methacrylate, nBMA indicates n-butyl methacrylate, and PME-200 ("Nippon Oil Co., Ltd.""Blemmer") means methoxy polyethylene glycol monomethacrylate. Specifically, PME-200 is a polymer of a monomer represented by CH ₂ = C (CH ₃ ) COO (C ₂ H ₄ O) _n -CH ₃ (n ≒ 4).

<Synthesis Example 8> (Synthesis of Polymer (B-8)) Except that all monomers were polymerized together, the monomers described in Table 1 below were performed in the same manner as in the methods described in Synthesis Example 5 to Synthesis Example 7. Synthesis of polymer (B-8) with composition ratio (mass ratio). The polymer (B-8) is a random copolymer.

[Table 1]

<Synthesis Example 9> (Synthesis of tungsten cesium oxide powder) A tungsten cesium oxide (Cs _0.33 WO ₃ ) powder was synthesized using a method described in paragraph [0113] of Japanese Patent No. 4096205.

The polymers and solvents used in Production Examples, Examples, and Comparative Examples are shown below. (Polymer) · B-1 to B-3: Polymers (B-1) to (B-3) of Table 1 synthesized in Synthesis Example 5 to Synthesis Example 7 · B-4: Pike "BYK-LPN6919" by BYK-Chemie (solid content concentration: 61% by mass, amine value: 120 mgKOH / g) · B-5: "BYK-2001" (solid by BYK-Chemie) Component concentration 46% by mass, amine value 29 mgKOH / g) · B-6: BYK-2000 (BYK-Chemie) (solid content concentration 40% by mass, amine value 4 mgKOH / g) · B -7: "BYK-LPN22102" by BYK-Chemie (solid content concentration: 38.5% by mass, amine value: 23 mgKOH / g) · B-8: Polymerization of Table 1 synthesized in Synthesis Example 8 (B-8)

(Solvent) CPN: cyclopentanone (SP value: 10.0) CHN: cyclohexanone (SP value: 9.9) GBL: γ-butyrolactone (SP value: 9.9) Tol: toluene (SP value: 8.9) PGMEA: propylene glycol Monomethyl ether acetate (SP value: 8.7)

[Preparation Example 1] (Preparation of Dispersion Liquid (X-1)) 25.00 parts by mass of the tungsten cesium oxide, 13.11 parts by mass of the polymer (B-4), and cyclopentanone (CPN) as a solvent (dispersion medium) were prepared. ) 61.89 parts by mass. These were filled into a container with 2000 parts by mass of zirconia particles having a diameter of 0.1 mm, and dispersed with a paint shaker, thereby obtaining a dispersion liquid (X-1) having an average particle diameter (D50) of 19 nm. In addition, the average particle diameter was measured using a light scattering measurement device ("ALV-5000" of ALV, Germany) by a dynamic light scattering (DLS) method.

[Preparation Example 2 to Preparation Example 15] (Preparation of Dispersion Liquid (X-2) to Dispersion Liquid (X-15)) A dispersion liquid was obtained in the same manner as in Preparation Example 1 except that the components shown in Table 2 were used. X-2) to dispersion (X-15). The average particle diameter (D50) of the particles in the obtained dispersion liquid is also shown in Table 2. CsWO in Table 2 represents tungsten cesium oxide obtained in Synthesis Example 9.

[Table 2]

[Example 1] 50.00 parts by mass of the dispersion liquid (X-1), 0.75 parts by mass of an organic pigment (C-1), and a polymerizable compound, "Kayalad ( KAYARAD) DPHA "(mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate) 6.26 parts by mass of" NCI-930 "(O-acetamido oxime based on ADEKA) as a polymerization initiator Compound) 1.46 parts by mass, 0.02 parts by mass of "FTX-218D" (fluorine-based surfactant) of NEOS Corporation as a surfactant, and "Irganox" of BASF as an antioxidant 1010 "(phenol-based antioxidant) 0.01 parts by mass and 41.50 parts by mass of cyclopentanone (CNP) as an additional solvent were mixed with a blender. A 0.5 μm filter made of polytetrafluoroethylene (PTFE) was used to pressure-filter 200 mL of the mixture at 0.5 MPa for 3 minutes to obtain the composition (Z-1) of Example 1. The solubility of the organic pigment (C-1) in the solvent (CPN) at 20 ° C and 0.1 MPa is 2% by mass or more. Here, the solubility is calculated | required by the following method. First, an organic pigment is added to the solvent (the amount added at this time is equivalent to 10% by mass relative to the entire solution), the obtained solution is heated to 50 ° C, and then left at room temperature (20 ° C) for 12 hours. . The solubility (20 ° C) of each dye with respect to the solvent was calculated based on the amount of each organic pigment remaining after dissolution.

[Example 2 to Example 23, Comparative Example 1 to Comparative Example 13] Except that the composition of each component was as shown in Tables 1 to 7, Examples 2 to 23 and Comparative Examples were obtained in the same manner as in Example 1. Each composition (Z-2) to composition (Z-23) and composition (Y-1) to composition (Y-13) of Examples 1 to Comparative Example 13. Tables 3 to 7 also show the solubility of the organic pigments used with respect to the solvent used. Furthermore, a solvent derived from a polymer solution is also contained in each composition. The values in the table are also taken into account.

[Evaluation] The following evaluations were performed using each of the obtained compositions. The evaluation results are shown in Tables 3 to 7.

(Dispersion stability) Using a 0.5 μm filter made of polytetrafluoroethylene (PTFE), 200 mL of each composition was subjected to pressure filtration at 0.5 MPa for 3 minutes. Based on the recovery of the filtrate at this time, the dispersion stability (filterability, precipitation suppression) was evaluated using the following criteria. In the case of A or B, the evaluation was that the dispersion stability was good, and in the case of A, the evaluation was particularly excellent. Furthermore, when there are many traps of agglomerates and the recovery rate is less than 90% (C), the filtration becomes insufficient, and productivity is significantly reduced. A: 95% or more B: 90% or more and less than 95% C: 90% or less

The following evaluations were performed using the filtered composition.

Each composition was applied to a glass substrate by a spin coating method so as to have a predetermined film thickness. After that, the coating film was heated at 100 ° C. for 120 seconds, and exposed to 1000 mJ / cm ² using an i-ray stepper. Then, an infrared shielding film having an average film thickness of 1.40 μm to 1.60 μm was produced on the glass substrate by heating at 220 ° C. for 300 seconds. Each average film thickness is shown in Tables 3-7. The thickness of the film was measured using a stylus-type step meter ("α Step IQ" of Yamato Scientific Co., Ltd.). Next, the transmittance in each wavelength region of the infrared shielding film produced on the glass substrate was comparatively measured with a glass substrate using a spectrophotometer ("V-7300" of Japan Spectroscopy Corporation). Based on the obtained spectrum, evaluation was performed by the evaluation criteria described below.

(Visible light transmittance) The average transmittance of visible light with a wavelength of 450 nm to 550 nm was calculated. When the average transmittance is less than 70%, the sensitivity of the solid-state imaging device when used as an infrared shielding film decreases. The average transmittance was evaluated using the following criteria. A: 80% or more B: 70% or more and less than 80% C: 70% or less

(Infrared shielding property 1) The average transmittance of infrared rays with a wavelength of 700 nm to 900 nm was calculated. When the average transmittance is 20% or more, the noise amount of the solid-state imaging element increases when it is used as an infrared shielding film. The average transmittance was evaluated using the following criteria. A: less than 15% B: 15% or more and less than 20% C: 20% or more

(Infrared Shielding Property 2) Regarding the transmittance of infrared rays having a wavelength of 1200 nm, it can be said that the transmittance is less than 15% and shows a practically good infrared shielding property. The transmittance at a wavelength of 1200 nm was evaluated using the following criteria. A: Less than 10% B: More than 10% and less than 15% C: 15% or more

(S / N ratio) The ratio (S / N ratio) of the average transmittance (S) in the visible region (450 nm-550 nm) to the average transmittance (N) in the infrared region (700 nm-900 nm) is obtained. , To speculate on practical performance. The higher the value of the S / N ratio, the better the performance. When it is 5 or more, it is judged to be practical and usable. The S / N ratio was evaluated using the following criteria. A: 5 or more B: less than 5

(Defect Inhibition) A hardened film having a film thickness of 1 μm was formed by the same method as in paragraph [0139]. The defect density of the cured film was measured using a defect / foreign substance inspection device ("KLA 2351" by KLA-Tencor). It can be determined that the smaller the value of the defect density is, the higher the defect suppression property is. The defect is a detection point having a size of 1 μm or more. Based on the defect density, defect suppression properties were evaluated using the following criteria. A: 10 / cm ² or less B: Beyond 10 / cm ² and is 50 / cm ² or less C: more than 50 / cm ²

(Stability over time: Thickening rate) After the composition was stored at 40 ° C for 3 days, the viscosity was measured before and after storage. The viscosity was measured using an E-type viscometer (E-type viscometer RE-80L manufactured by Toki Sangyo Co., Ltd.) while maintaining the coating liquid at 20 ° C. When the viscosity before storage is set to V1 and the viscosity after storage is set to V2, the value of (| V2-V1 | / V1) x 100 is defined as the viscosity increase ratio (%). Based on the said thickening rate, it evaluated using the following criteria. The lower the viscosity increase value, the better. It is judged to be practical when it is less than 10%. A: less than 5% B: more than 5% and less than 10% C: more than 10%

(Stability over time: number of defects) After the composition was stored at 40 ° C for 3 days, the number of defects was measured using the composition after storage. The measurement method and the reference are the same as the evaluation of the "defect suppression property".

(Pattern) Composition Z-1 to Composition Z-13, Composition Z-17 to Composition Z-18, Composition Z-23, Composition Y-1 to Composition Y-8, and Composition Y -10, using a spin coating method to form a coating film having a thickness of 1 μm on a silicon substrate. Then, after heating at 100 ° C. for 120 seconds, an i-ray stepper was used to expose 1000 mJ / cm ² through a mask having an L / S pattern of 50 μm. The non-exposed portion was removed by immersing the exposed substrate in acetone for development. Then, an infrared shielding film having an L / S pattern was produced by heating at 220 ° C for 300 seconds. As a result of observation with an optical microscope, it was confirmed that an L / S pattern with a line width of 50 μm was formed.

Regarding composition Z-14 to composition Z-16, composition Z-19 to composition Z-22, and composition Y-9, except that the developing solution was changed to a 2.38% TMAH solution, infrared rays were produced by the same method. Masking film. As a result of observation with an optical microscope, it was confirmed that a 50 μm L / S pattern was formed.

[table 3]

[Table 4]

[table 5]

[TABLE 6]

[TABLE 7]

As shown in Tables 3 to 7, it can be seen that the compositions Z-1 to Z-23 of Examples 1 to 23 have high dispersion stability and time-dependent stability, and also have good patternability. In addition, it was found that the infrared shielding film (optical filter) obtained from these compositions has few defects and has both good visible light transmission and infrared shielding properties. [Industrial availability]

The composition for a solid-state imaging element of the present invention can be preferably used as a forming material for an optical filter, more specifically, an infrared filter, and the like of a solid-state imaging element.

Claims (11)

A composition for a solid-state imaging element, comprising an inorganic compound, a polymer, an organic pigment, and a solvent, the amine value of the polymer is 90 mgKOH / g or more and 200 mgKOH / g or less, and the solvent includes a solubility parameter of 8.8 ( cal / cm ³ ) ^1/2 or more and 12.0 (cal / cm ³ ) ^1/2 or less, the content of the specific solvent relative to the entire composition for the solid-state imaging element is 40% by mass or more and 90% by mass % Or less, the solubility of the organic pigment in the solvent at 20 ° C and 0.1 MPa is 2% by mass or more. The composition for a solid-state imaging element according to item 1 of the patent application scope, which contains two or more kinds of the organic pigments. The composition for a solid-state imaging element according to item 1 or 2 of the scope of patent application, wherein the solvent includes a solvent having a ring structure. The composition for a solid-state imaging device according to item 3 of the scope of patent application, wherein the solvent having a cyclic structure is a cyclic ketone, a cyclic ether, a lactone, a lactam, an aromatic hydrocarbon, or a combination thereof . The composition for a solid-state imaging element according to any one of claims 1 to 4, wherein the organic pigment has a maximum absorption wavelength in a range of 600 nm to 1,000 nm. The composition for a solid-state imaging element according to any one of claims 1 to 5, wherein the organic pigment is a diimide compound, a squarylium compound, a cyanine compound, or a phthalocyanine compound. , Naphthalocyanine compound, quartrenene compound, ammonium compound, imine compound, azo compound, anthraquinone compound, porphyrin compound, pyrrolopyrrole compound, oxacyanine compound, ketonium compound, six-membered porphyrin A compound or combination of these. The composition for a solid-state imaging element according to any one of claims 1 to 6, wherein the polymer is a block copolymer, and the block copolymer has a function including a nitrogen atom-containing function. A block of a base, and a block having an affinity for a vehicle. The composition for a solid-state imaging device according to any one of claims 1 to 7, wherein the inorganic compound is tungsten cesium oxide, quartz, magnetite, alumina, titania, zirconia, sharp Spar or a combination of these. The composition for a solid-state imaging element according to any one of claims 1 to 8, further comprising a polymerizable compound. A method for forming an infrared shielding film for a solid-state imaging element, comprising the step of forming a coating film on one surface side of a substrate, and using the solid-state imaging element according to any one of claims 1 to 9 of a patent application scope. Composition to form the coating film. The method for forming an infrared shielding film for a solid-state imaging element according to item 10 of the scope of patent application, further comprising: a step of irradiating at least a part of the coating film with radiation, and developing the coating film after radiation irradiation. A step of.