WO2021044985A1

WO2021044985A1 - Metal oxide particle dispersion composition and dispersion method for metal oxide particles

Info

Publication number: WO2021044985A1
Application number: PCT/JP2020/032717
Authority: WO
Inventors: 媛▲青▼ 張; 博樹千坂; 大塩田
Original assignee: 東京応化工業株式会社
Priority date: 2019-09-02
Filing date: 2020-08-28
Publication date: 2021-03-11
Also published as: JP2021037463A; CN114302923A; CN114302923B; KR20220057567A; JP7356846B2

Abstract

Provided is a metal oxide particle dispersion composition enabling preparation of a high-refractive material which exhibits excellent heat-resistance performance, to which an inkjet method can be applied, and which is for forming a high-refractive layer in OLED illumination and the like or for use in a display such as an OLED display element.　This metal oxide particle dispersion composition contains: a specific silyl group-modified fluorene compound in which a naphthalene ring is bound to fluorene; and a specific (meth)acrylate compound. The silyl group is preferably a trimethoxysilyl group, a triethoxysilyl group, a methyldimethoxysilyl group, an ethyldimethoxysilyl group, a methyldiethoxysilyl group, or an ethyldiethoxysilyl group.

Description

Composition for Dispersing Metal Oxide Particles and Dispersion Method of Metal Oxide Particles

The present invention relates to a composition for dispersing metal oxide particles and a method for dispersing metal oxide particles.

A high refractive index material is used to form the optical member. As the highly refracting material, for example, a material in which metal oxide particles such as titanium oxide and zirconium oxide are dispersed in an organic component is used.
As such a highly refracting material, a composition containing metal oxide particles and a fluorene compound having a specific structure in which a benzene ring is bonded to fluorene and has a hydrolyzable silyl group is disclosed (see Patent Document 1). Since the composition of Patent Document 1 contains a fluorene compound having a specific structure in which a benzene ring is bonded to fluorene and has a hydrolyzable silyl group, it has a high refractive index and is excellent in dispersibility of metal oxide particles.

Japanese Unexamined Patent Publication No. 2012-233142

However, the composition of Patent Document 1 has a problem of insufficient heat resistance. Insufficient heat resistance causes problems such as generation of outgas derived from organic components due to heating, which is not preferable for use in display applications such as OLED display elements or in high bending layers in OLED lighting and the like.
Further, the composition of Patent Document 1 has a problem that it is difficult to apply the inkjet method to the film formation because there is a risk of concentration change, ejection failure, deterioration of curing sensitivity, etc. when the film is formed by the inkjet method. ..
Therefore, a highly refracting material having excellent heat resistance and to which the inkjet method can be applied is required. Therefore, a composition for dispersing metal oxide particles capable of preparing the highly refracting material by mixing the metal oxide particles. Is desired.

The present invention has been made in view of the above-mentioned problems of the prior art, and is excellent in heat resistance and can be applied to an inkjet method, for display applications such as OLED display elements, or for forming a high bending layer in OLED lighting and the like. It is an object of the present invention to provide a composition for dispersing metal oxide particles capable of preparing a highly refracting material, and a method for dispersing metal oxide particles.

The present inventors assume that the composition for dispersing metal oxide particles contains a silyl group-modified fluorene compound having a specific structure and a (meth) acrylate compound having a specific structure, and the composition in which metal oxide particles are dispersed therein. We have found that a substance (highly refracting material) has excellent heat resistance and can apply an inkjet method, and have completed the present invention. That is, the present invention is as follows.

The first aspect of the present invention is for dispersing metal oxide particles containing a silyl group-modified fluorene compound represented by the following formula (1) and a (meth) acrylate compound represented by the following formula (2). It is a composition.

(In the formula (1), the ring Z ¹ represents a naphthalene ring and represents a naphthalene ring.
R ^1a and R ^1b independently represent a halogen atom, a cyano group or an alkyl group, respectively.
R ^2a and R ^2b each independently represent an alkyl group and represent an alkyl group.
R ^3a and R ^3b each independently represent an alkylene group and represent an alkylene group.
X ^a and X ^b each independently represent a group represented by -Si (OR ⁴ ) _p (R ⁵ ) _3-p.
R ⁴ represents a hydrogen atom, an alkyl group or a group represented by- ^{(R 6} O) _q- ^{R 7.}
R ⁵ represents a hydrogen atom or a hydrocarbon group.
R ⁶ represents an alkylene group
R ⁷ represents an alkyl group
k1 and k2 independently represent integers of 0 or more and 4 or less, respectively.
m1 and m2 independently represent integers of 0 or more and 2 or less, respectively.
p represents an integer of 1 or more and 3 or less,
q represents an integer of 1 or more. )

(In formula (2), Z ² represents an aromatic group containing two or more aromatic rings, R ⁸ represents a linear or branched alkylene group, R ⁹ represents a hydrogen atom or a methyl group, and r Represents an integer greater than or equal to 0.)

In the second aspect of the present invention, the metal oxide particle dispersion composition according to the first aspect and the metal oxide particles are mixed, and the metal oxide particles are contained in the metal oxide particle dispersion composition. It is a method of dispersing metal oxide particles.

Since the composition for dispersing metal oxide particles of the present invention contains a silyl group-modified fluorene compound represented by the formula (1) and a (meth) acrylate compound represented by the formula (2), the metal oxide particles By dispersing the above, it is possible to prepare a highly refracting material having excellent heat resistance and to which the inkjet method can be applied. This highly refracting material is suitable for display applications such as OLED display elements or for forming a high bending layer in OLED lighting and the like. Further, the composition for dispersing metal oxide particles of the present invention has good dispersibility of metal oxide particles and a high refractive index.

<< Composition for Dispersing Metal Oxide Particles >>
The composition for dispersing metal oxide particles of the present invention contains a silyl group-modified fluorene compound represented by the following formula (1) and a (meth) acrylate compound represented by the following formula (2).
Hereinafter, the components contained in the composition for dispersing metal oxide particles will be described in order.

<Cyril group-modified fluorene compound represented by the formula (1)>
The composition for dispersing metal oxide particles contains a silyl group-modified fluorene compound represented by the following formula (1).

^{Specific examples of the halogen atom as R 1a} and R ^1b in the above formula (1) include a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom.
In the above formula (1), ^{the alkyl groups as R 1a} and R ^1b may be linear or branched, and may be, for example, methyl group, ethyl group, propyl group, isopropyl group, butyl. Examples thereof include alkyl groups having 1 or more and 6 or less carbon atoms such as groups and tert-butyl groups.
R ^1a and R ^1b may be the same or different.
If k1 is 2 or more, 2 or more R ^1a may be the same or different, when k2 is 2 or more, 2 or more R ^1b may be the same or different.
k1 and k2 are independently integers of 0 or more and 4 or less, preferably 0 or 1, and preferably 0.
k1 and k2 may be the same or different.

In the above formula (1), ^{the alkyl group as R 2a} and R ^2b may be linear or branched, and may be, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, or butyl. Group, tert-butyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, n-hexyl group, isohexyl group, sec-hexyl group, tert-hexyl group, etc. Examples thereof include an alkyl group having 18 or less, preferably an alkyl group having 1 or more and 8 or less carbon atoms, and preferably an alkyl group having 1 or more and 6 or less carbon atoms.
R ^2a and R ^2b may be the same or different.
When m1 is 2, the two R ^2a may be the same or different, and when m2 is 2, the two R ^2b may be the same or different.
m1 and m2 are independently integers of 0 or more and 2 or less, and are preferably 0 or 1.
m1 and m2 may be the same or different.

In the above formula (1), ^{the alkylene group as R 3a} and R ^3b is an alkylene group having 2 or more and 10 or less carbon atoms such as an ethylene group, a trimethylene group, a propylene group, a butane-1,2-diyl group and a hexylene group. The alkylene group having 2 or more and 6 or less carbon atoms is preferable, the alkylene group having 2 or more and 4 or less carbon atoms is more preferable, and the alkylene group having 2 or 3 carbon atoms is further preferable.
R ^3a and R ^3b may be the same or different.

In the above formula (1), ^{the alkyl group as R 4} includes a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group and a tert. -Alkyl groups having 1 to 10 carbon atoms such as pentyl group, n-hexyl group, isohexyl group, sec-hexyl group, and tert-hexyl group can be mentioned, and alkyl groups having 1 to 6 carbon atoms are preferable. , An alkyl group having 1 or more and 4 or less carbon atoms is more preferable, and an alkyl group having 1 or 2 carbon atoms is further preferable.
If R ⁴ is plural, R ⁴ may be the same or different.

In the above formula (1), the hydrocarbon group as R ^5, or alkyl group, and an unsaturated hydrocarbon group such as an aryl group.
Alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, butyl group, tert-butyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, n-hexyl group and isohexyl group. , Se-hexyl group, tert-hexyl group and other alkyl groups having 1 to 10 carbon atoms are preferable, and alkyl groups having 1 to 6 carbon atoms are preferable, and alkyl groups having 1 to 4 carbon atoms are preferable. Is more preferable.
Examples of the aryl group include an aryl group having 6 to 10 carbon atoms such as a phenyl group and a tolyl group.
If R ⁵ is more, the plurality of R ⁵ may be the same or different.

In the above formula (1), ^{the alkylene group as R 6 is the same} as the alkylene group described for R ^3a and R ^3b .
If R ⁶ is plural, R ⁶ may be the same or different.

In the above formula (1), the alkyl group as ^{R 7 is the same} as the alkyl group described for ^{R 4.}
If R ⁷ is plural, R ⁷ may be the same or different.

In the above formula (1), p is an integer of 1 or more and 3 or less, preferably 2 or 3, and particularly preferably 3 from the viewpoint of hydrolysis condensability.
q is an integer of 1 or more, and is, for example, 1 or more and 10 or less, preferably 1 or more and 6 or less, more preferably 1 or more and 4 or less, still more preferably 1 or 2, and particularly preferably 1.

X ^a and X ^b may be the same or different.
Specific examples of X ^a and X ^b , that is, -Si (OR ⁴ ) _p (R ⁵ ) _3-p , include a trimethoxysilyl group, a triethoxysilyl group, a methyldimethoxysilyl group, an ethyldimethoxysilyl group, and a methyldiethoxy. Examples thereof include a silyl group and an ethyldiethoxysilyl group.

The silyl group-modified fluorene compound represented by the formula (1) is preferably a silyl group-modified fluorene compound represented by the following formula (1-1).
In the equation (1-1), ^R 2a attached to the naphthalene ^{_{_{_{ring, R 2b, -O-CH 2}}}} -CH 2 -CH 2 -S-R 3a -X a or _-O-CH 2 -CH _2- CH _2- SR ^3b- ^Xb is bonded to a 6-membered ring which is not bonded to a fluorene ring among the 6-membered rings constituting the naphthalene ring.

(In equation (1-1), R ^1a , R ^1b , R ^2a , R ^2b , R ^3a , R ^3b , X ^a , X ^b , R ⁴ , R ⁵ , R ⁶ , R ⁷ , k1, k2, m1 , M2, p and q are the same as those in the formula (1), respectively.)

Specific examples of the silyl group-modified fluorene compound represented by the formula (1) are illustrated below, but the present invention is not limited thereto.

The silyl group-modified fluorene compound represented by the above formula (1) can be produced by using an arbitrary organic synthesis reaction.
For example, at room temperature, a fluorene compound having an allyloxy group represented by the following formula (i) and a compound represented by the following formula (ii) such as (3-mercaptopropyl) trimethoxysilane (MPTMS) are radically divided. It can be synthesized by photoreacting in a solvent such as tetrahydro (THF) in the presence of a polymerization initiator. In addition, triphenylphosphine triphenylborane may be used together with a radical polymerization initiator. The exposure wavelength at the time of reaction is, for example, broadband light including i-line (365 nm).
The fluorene compound having an allyloxy group represented by the following formula (i) and the compound represented by the following formula (ii) are, for example, fluorene having an allyloxy group represented by the following formula (i) on a mass basis. Compound: It is preferable to use an amount of the compound represented by the following formula (ii) = 1: 3 to 5.

The fluorene compound having an allyloxy group represented by the above formula (i) can be synthesized by allylating the fluorene compound having a hydroxy group represented by the following formula (iii). For example, by reacting a fluorene compound having a hydroxy group represented by the following formula (iii) with an allyl halide such as allyl bromide in the presence of a base such as sodium hydroxide or potassium hydroxide, the above formula (i) A fluorene compound having an allyloxy group represented by is capable of being synthesized. Examples of the fluorene compound having a hydroxy group represented by the following formula (iii) include 9,9-bis (6-hydroxynaphthyl) fluorene.

The composition for dispersing metal oxide particles may contain one kind of silyl group-modified fluorene compound represented by the formula (1) alone or a mixture of two or more kinds.
In the above composition for dispersing metal oxide particles, the content of the silyl group-modified fluorene compound represented by the formula (1) is not particularly limited as long as the effects of the present invention can be achieved, but is represented by the formula (1). The ratio of the mass of the silyl group-modified fluorene compound represented by the formula (1) to the total mass of the silyl group-modified fluorene compound and the mass of the (meth) acrylate compound represented by the formula (2) is 1% by mass or more. The mass ratio of the silyl group-modified fluorene compound represented by the formula (1) is more preferably 5% by mass or more, and the mass of the silyl group-modified fluorene compound represented by the formula (1). Is more preferably 10% by mass or more. The upper limit of the mass ratio of the silyl group-modified fluorene compound represented by the formula (1) is not particularly limited, but from the viewpoint of high refractive index, the mass of the silyl group-modified fluorene compound represented by the formula (1). The ratio of the mass of the silyl group-modified fluorene compound represented by the formula (1) to the total mass of the (meth) acrylate compound represented by the formula (2) is preferably 50% by mass or less, preferably 30 mass. It is more preferably% or less, and further preferably 25% by mass or less.

<(Meta) acrylate compound represented by the formula (2)>
The composition for dispersing metal oxide particles contains a (meth) acrylate compound represented by the above formula (2) together with a silyl group-modified fluorene compound represented by the above formula (1). In addition, in this specification, "(meth) acrylate" means both "acrylate" and "methacrylate".

In the formula (2), the aromatic group containing two or more aromatic rings as Z ² may have a substituent, preferably the number of aromatic ring within Z ² is 5 or less, It is more preferably 3 or less. As for the number of aromatic rings, the number of benzene rings is counted as one, and for the naphthalene ring, which is a condensed ring, the number of rings is 2.
Examples of the ^{aromatic ring contained in Z 2} include a benzene ring and a naphthalene ring.
The ^{substituents that the aromatic group as Z 2} may have include an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and an alkoxy group having 2 to 12 carbon atoms. Examples thereof include a carbonyl group, an acyl group having 1 to 12 carbon atoms, an acyloxy group having 1 to 12 carbon atoms, a hydroxyl group, a halogen atom, a cyano group or a nitro group.
An ^{aromatic group containing two or more aromatic rings as Z 2} is exemplified below, but the present invention is not limited thereto, and Z ² is a biphenyl group which may have the above-mentioned substituent. Alternatively, it is preferably a naphthyl group, more preferably a biphenyl group. In the following formula, * represents a bond.

In the formula (2), ^{examples of the linear or branched alkylene group as R 8} include a linear or branched alkylene group having 1 or more and 4 or less carbon atoms (preferably 2 or 3 carbon atoms). For example, a methylene group, an ethylene group, a trimethylene group, a propylene group, a butane-1,2-diyl group and the like can be mentioned.

From the viewpoint of higher heat resistance, r is preferably 0 or more and 3 or less, more preferably 0 or more and 2 or less, further preferably 0 or 1, and particularly preferably 0.

The composition for dispersing metal oxide particles may contain one kind of (meth) acrylate compound represented by the formula (2) alone or a mixture of two or more kinds.
In the above composition for dispersing metal oxide particles, the content of the (meth) acrylate compound represented by the formula (2) is not particularly limited as long as the effects of the present invention can be achieved, but is represented by the formula (1). The ratio of the mass of the (meth) acrylate compound represented by the formula (2) to the total mass of the silyl group-modified fluorene compound and the mass of the (meth) acrylate compound represented by the formula (2) is 50% by mass or more. The mass ratio of the (meth) acrylate compound represented by the formula (2) is more preferably 70% by mass or more, and the mass of the (meth) acrylate compound represented by the formula (2). Is more preferably 75% by mass or more. The upper limit of the mass ratio of the (meth) acrylate compound represented by the formula (2) is not particularly limited, but from the viewpoint of dispersibility, the mass and the formula of the silyl group-modified fluorene compound represented by the formula (1). The ratio of the mass of the (meth) acrylate compound represented by the formula (2) to the total mass of the (meth) acrylate compound represented by (2) is preferably 99% by mass or less, more preferably 95% by mass or less. , 90% by mass or less is more preferable.

<Radical polymerization initiator>
The composition for dispersing metal oxide particles may or may not further contain a radical polymerization initiator, but preferably contains a radical polymerization initiator. The radical polymerization initiator may be either a photoradical polymerization initiator or a thermal radical polymerization initiator, and a photoradical polymerization initiator and a thermal radical polymerization initiator may be used in combination.

Examples of the photoradical polymerization initiator include Omnirad 651, Omnirad 184 (1-hydroxycyclohexyl-phenylketone), Omnirad 1173, Omnirad 2959, Omnirad 127, Omnirad 907, Omnirad 397, Omnirad 369, Omnirad 369, Omnirad 369, and Omnirad 369. Alkylphenyl polymerization initiators such as V.), acylphosphine oxide-based polymerization initiators such as Omnirad TPO H and Omnirad 819 (all manufactured by IGM Resins VV), Irgacure OXE01, and Irgacure OXE02 (all). Examples thereof include an oxime ester-based polymerization initiator (manufactured by BASF).

Specific examples of the photoradical polymerization initiator include 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] -2. -Hydroxy-2-methyl-1-propane-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy- 2-Methylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, bis (4-dimethylaminophenyl) ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1-one, 1,2-octanedione, 1- [4- (phenylthio) ) Phenyl]-, 2- (O-benzoyloxime) (Irgacure OXE01), Etanone-1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-) Acetyloxym) (Irgacure OXE02), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Omnirad TPO H), bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Omnirad 819), 4-benzoyl-4 '-Methyldimethylsulfide, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, butyl 4-dimethylaminobenzoate, 4-dimethylamino-2-ethylhexyl benzoic acid, 4- Dimethylamino-2-isoamyl benzoic acid, benzyl-β-methoxyethyl acetal, benzyl dimethyl ketal, 1-phenyl-1,2-propandion-2- (O-ethoxycarbonyl) oxime, methyl O-benzoyl benzoate, 2 , 4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 1-chloro-4-propoxythioxanthone, thioxanthene, 2-chlorothioxanthene, 2,4-diethylthioxanthene, 2-methylthioxanthene, 2, -Isopropylthioxanthene, 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone, azobisisobutyronitrile, benzoylpa -Oxide, cumenehydroperoxide, 2-mercaptobenzoimider, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2- (O-chlorophenyl) -4,5-di (m-methoxyphenyl) -imidazolyl dimer , Benzophenone, 2-chlorobenzophenone, p, p'-bisdimethylaminobenzophenone, 4,4'-bisdiethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3-dimethyl-4-methoxybenzophenone, benzyl, benzoin, Benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, benzoin butyl ether, acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone , Trichloroacetophenone, p-tert-butylacetophenone, p-dimethylaminoacetophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, α, α-dichloro-4-phenoxyacetophenone, thioxanthone, 2-methylthioxanthone , 2-Isopropylthioxanthone, dibenzosverone, pentyl-4-dimethylaminobenzoate, 9-phenylacrine, 1,7-bis- (9-acrydinyl) heptane, 1,5-bis- (9-acrydinyl) pentane, 1, , 3-Bis- (9-acrydinyl) propane, p-methoxytriazine, 2,4,6-tris (trichloromethyl) -s-triazine, 2-methyl-4,6-bis (trichloromethyl) -s-triazine , 2- [2- (5-methylfuran-2-yl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- (fran-2-yl) ethenyl] -4, 6-bis (trichloromethyl) -s-triazine, 2- [2- (4-diethylamino-2-methylphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- ( 3,4-Dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2-( 4-Acetophenone) -4,6-bis (trichloromethyl) -s-triazine, 2 -(4-N-Butoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4-methoxy) phenyl-s-triazine, 2,4-Bis-trichloromethyl-6- (2-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (3-bromo-4-methoxy) styrylphenyl-s -Triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4-methoxy) styrylphenyl-s-triazine and the like can be mentioned. These photoradical polymerization initiators can be used alone or in combination of two or more. Above all, it is particularly preferable to use an oxime-based polymerization initiator in terms of sensitivity.

Examples of the thermal radical polymerization initiator include ketone peroxide (methyl ethyl ketone peroxide and cyclohexanone peroxide, etc.), peroxyketal (2,2-bis (tert-butylperoxy) butane and 1,1-bis (tert-butylper). Oxy) cyclohexane, etc.), hydroperoxide (tert-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxide (di-tert-butyl peroxide (perbutyl (registered trademark) D (manufactured by Nichiyu Co., Ltd.)), And di-tert-hexyl peroxide (perhexyl (registered trademark) D (manufactured by Nichiyu Co., Ltd.), etc.), diacyl peroxide (isobutyryl peroxide, lauroyl peroxide, benzoyl peroxide, etc.), peroxydicarbonate ( Diisopropyl peroxydicarbonate, etc.), peroxy ester (tert-butylperoxyisobutyrate and 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, etc.)} organic peroxides, 1 , 1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), 2,2' -Azobis (2-methylpropion amidine) dihydrochloride, 2,2'-azobis [2-methyl-N- (2-propenyl) propion amidine] dihydrochloride, 2,2'-azobis (2-methylpropionamide), 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (2-methylpropane), 2,2'-azobis (2,4,4-trimethyl) Pentan) and azo compounds such as dimethyl 2,2'-azobis (2-methylpropionate)} can be mentioned.

When the composition for dispersing metal oxide particles contains a radical polymerization initiator, the content of the radical polymerization initiator is not particularly limited as long as the object of the present invention is not impaired, and the content of the radical polymerization initiator is not particularly limited. Is 0.01% by mass or more and 30% by mass or less with respect to the total mass of the silyl group-modified fluorene compound represented by the above formula (1) and the mass of the (meth) acrylate compound represented by the formula (2). Preferably, it is more preferably 0.05% by mass or more and 15% by mass or less, and further preferably 0.08% by mass or more and 10% by mass or less.

<Organic solvent>
The composition for dispersing metal oxide particles may contain an organic solvent, but the content of the organic solvent is preferably 10% by mass or less, more preferably 5% by mass or less, and does not contain an organic solvent. Is even more preferable.
When the composition for dispersing metal oxide particles contains an organic solvent, when the inkjet method is applied, there is a problem that the concentration of the contained components may change due to the volatilization of the organic solvent, the ejection may be poor, and the curing sensitivity may be deteriorated. These problems can be suppressed by using a composition for dispersing metal oxide particles having a solvent content of 10% by mass or less, 5% by mass or less, and further containing no organic solvent.

When an organic solvent is contained, examples of the organic solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol. Mono-n-propyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono -N-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, etc. (Poly) alkylene glycol monoalkyl ethers; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc. Poly) alkylene glycol monoalkyl ether acetates; other ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, tetrahydrofuran; ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone, 3-heptanone; 2-hydroxypropion Lactate alkyl esters such as methyl 2-hydroxy-2-methylpropionate; ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3- Ethyl ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propione G, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl formate, isopentyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate. , Methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetate, ethyl acetate, ethyl 2-oxobutanoate and other esters; aromatic hydrocarbons such as toluene and xylene; N-methylpyrrolidone , N, N-dimethylformamide, N, N-dimethylacetamide and other amides. These solvents may be used alone or in combination of two or more.

Since the composition for dispersing metal oxide particles contains a silyl group-modified fluorene compound represented by the formula (1) and a (meth) acrylate compound represented by the formula (2), it will be shown in Examples described later. As such, it has excellent heat resistance.
Further, since the silyl group-modified fluorene compound represented by the formula (1) has a high refractive index, the composition for dispersing metal oxide particles has a high refractive index.
The composition for dispersing metal oxide particles can reduce the content of the organic solvent to 10% by mass or less or 5% by mass or less, and can also prevent the composition from containing the organic solvent. Therefore, the inkjet method can be applied because it is possible to suppress changes in the concentration of contained components due to volatilization of the organic solvent, poor ejection, and deterioration of curing sensitivity.
Further, the composition for dispersing metal oxide particles has good dispersibility of metal oxide particles.
Therefore, by mixing the above composition for dispersing metal oxide particles with metal oxide particles having a high refractive index to disperse the metal oxide particles, the heat resistance is excellent and the inkjet method can be applied. The material can be prepared.
As described above, since the high refractive index and the excellent heat resistance suppress the generation of outgas, the high refractive index material can be applied as a high bending layer in display applications or OLED lighting applications. For example, it can be applied to the high refraction layer of OLED. Further, since the inkjet method can be applied to the high-refraction material, for example, a coating film made of the high-refraction material can be easily formed.

<Other polymerizable compounds>
The composition for dispersing metal oxide particles is any polymerizable compound other than the silyl group-modified fluorene compound represented by the above formula (1) and the (meth) acrylate compound represented by the above formula (2) (“Other”. The polymerizable compound of the above formula (1) may or may not be contained, and examples of the other polymerizable compounds include a silyl group-modified fluorene compound represented by the above formula (1) and the above formula (2). Examples thereof include a resin having an ethylenically unsaturated group, a monomer having an ethylenically unsaturated group, or a combination thereof other than the (meth) acrylate compound represented by.

(Monomer having an ethylenically unsaturated group)
Monomers having an ethylenically unsaturated group include monofunctional monomers and polyfunctional monomers. Hereinafter, the monofunctional monomer and the polyfunctional monomer will be described in order.

Examples of the monofunctional monomer include (meth) acrylamide, methylol (meth) acrylamide, methoxymethyl (meth) acrylamide, ethoxymethyl (meth) acrylamide, propoxymethyl (meth) acrylamide, butoxymethoxymethyl (meth) acrylamide, and N-methylol ( Meta) acrylamide, N-hydroxymethyl (meth) acrylamide, (meth) acrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, crotonic acid, 2-acrylamide- 2-Methylpropanesulfonic acid, tert-butylacrylamide sulfonic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (Meta) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybuty (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, Glycerin mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dimethylaminoethyl (meth) acrylate, glycidyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3 -Tetrafluoropropyl (meth) acrylate, half (meth) acrylate of phthalic acid derivative and the like can be mentioned. These monofunctional monomers may be used alone or in combination of two or more.

Examples of the polyfunctional monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and butylene glycol di ( Meta) acrylate, neopentyl glycol di (meth) acrylate, alkylene oxide-modified neopentyl glycol diacrylate with 1 to 5 carbon atoms (among others, propylene oxide-modified neopentyl glycol diacrylate) 1,6-hexane glycol di (meth) ) Acrylate, Trimethylol Propanetri (meth) Acrylate, Glycerindi (Meta) Acrylate, Pentaerythritol Triacrylate, Pentaerythritol Tetraacrylate, Dipentaerythritol Pentaacrylate, Dipentaerythritol Hexaacrylate, Pentaerythritol di (meth) Acrylate, Penta Elythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 2,2-bis (4- (meth) acryloxidiethoxyphenyl) Propane, 2,2-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol Diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate, glycerin triacrylate, glycerin polyglycidyl ether poly (meth) acrylate, urethane (meth) acrylate (ie, tolylene diisocyanate), trimethylhexamethylene Diisocyanate, hexamethylene Diisocyanate and 2-hydroxyethyl (meth) acrylate reaction product, methylenebis (meth) acrylamide, (meth) acrylamide methylene ether, polyhydric alcohol and N-methylol (meth) acrylamide condensate, etc. Examples include functional monomers and triacrylic formal. These polyfunctional monomers may be used alone or in combination of two or more.

The composition for dispersing metal oxide particles may or may not contain a resin other than the resin used as the other polymerizable compound. Examples of the other resins include alkali-soluble resins and resins whose solubility in a developing solution changes due to the action of an acid.

In the present specification, the alkali-soluble resin refers to KOH having a concentration of 0.05% by mass by forming a resin film having a thickness of 1 μm on a substrate with a resin solution (solvent: propylene glycol monomethyl ether acetate) having a resin concentration of 20% by mass. A solvent that dissolves in a film thickness of 0.01 μm or more when immersed in an aqueous solution for 1 minute.

<Other ingredients>
The composition for dispersing metal oxide particles may contain various additives, if necessary. Specifically, sensitizers, curing accelerators, photocrosslinkers, dispersion aids, fillers, adhesion promoters, silane coupling agents, antistatic agents, antioxidants, UV absorbers, anti-aggregation agents, heat. Examples thereof include polymerization inhibitors, plasticizers, flame retardants, defoamers, leveling agents, thickeners, thixophilic imparting agents, and surfactants.

Examples of the thermal polymerization inhibitor used in the composition for dispersing metal oxide particles include hydroquinone and hydroquinone monoethyl ether. Further, examples of the defoaming agent include silicone-based and fluorine-based compounds, and examples of the surfactant include anion-based, cationic and nonionic compounds.

(Method for preparing the above composition for dispersing metal oxide particles)
The composition for dispersing metal oxide particles includes a membrane filter of 0.2 μm or less, a membrane filter of 0.5 μm or more and 1 μm or less, and the like, if necessary, after the above components are uniformly stirred, mixed, and dispersed. It can be prepared by filtering with a filter.

<< High refraction material >>
By mixing and dispersing the metal oxide particles, the composition for dispersing the metal oxide particles becomes a highly refracting material that can be preferably used for forming a high bending layer in a display application or the like or in OLED lighting or the like.
As described above, this highly refracting material has excellent heat resistance, and an inkjet method can be applied. In addition, the dispersibility of the metal oxide particles is also excellent.

<Metal oxide particles>
In the metal oxide particles, the metal oxide can be appropriately selected depending on the application, and the metal of the metal oxide includes, for example, a transition metal [for example, a Group 3 metal in the periodic table (for example, yttrium, cerium, etc.), a period. Group 4 metals (eg, titanium, zirconium, hafnium, etc.), Periodic Group 4 metals (eg, niobium, tantalum, etc.), Periodic Table Group 6 metals (eg, tungsten), Periodic Table Group 8 metals (eg, Tungsten). , Iron, etc.], Periodic Table Group 10 metals (eg, zinc, etc.), Periodic Table Group 13 metals (eg, aluminum, indium, etc.), Periodic Table Group 14 metals (eg, germanium, tin, etc.), etc. Can be mentioned. Silicon is not included in the metal. The metal oxide may be an oxide containing a single metal or an oxide (or a compound oxide) containing two or more kinds of metals.

Representative metal oxides (particles) include, for example, metal oxides (particles) containing at least one non-silicon-based metal selected from titanium, zirconium, aluminum, and zinc.

In particular, from the viewpoint of high refractive index, the metal oxide may be a metal oxide containing at least one selected from zirconium and titanium.

The metal oxide may be a natural product (or mineral) or the like, and is obtained by hydrolysis of a hydrolyzable condensable compound (that is, a hydrolyzable condensable metal compound, for example, a metal alkoxide) corresponding to the metal of the metal oxide. It may be the obtained hydrolyzed condensate (so-called metal oxide obtained by the sol-gel method). That is, the metal oxide particles (metal oxide) may be a hydrolyzed condensate of a condensing component (hydrolyzed condensable component) composed of a hydrolyzable condensable metal compound.

The surface of the metal oxide particles usually has a functional group (a functional group derived from a solgel reaction raw material such as a hydroxyl group directly bonded to a metal atom or a hydrolyzable condensable group such as an alkoxy group). In many cases. Then, such a functional group easily reacts with the silyl group of the silyl group-modified fluorene compound represented by the above formula (1) (hydrolysis condensation reaction) to stabilize the metal oxide particles. Such a functional group may be a functional group existing in the metal oxide particles themselves, or may be further introduced by surface-treating the metal oxide particles, and is a functional group derived from the raw material of the sol-gel method. It may be.

In the metal oxide particles obtained by hydrolysis condensation, the hydrolysis-condensable compound includes a hydrolysis-condensable group (for example, an alkoxy group, an aryloxy group, etc.) directly bonded to a metal atom (for example, zirconium, titanium, etc.). Examples thereof include compounds having at least one halogen atom (such as a halogen atom such as a chlorine atom and a hydroxyl group).

Representative examples of hydrolyzable and condensable metal compounds (or hydrolyzable and condensable organic metal compounds) include metal alkoxides (alkoxides of the above-exemplified metals), such as zirconium alkoxides [eg, tetraalkoxide zirconium (eg, tetramethoxyzirconium, etc.). _{Tetra C 1-18} alkoxide zirconium, such as tetraethoxyzinczyl, tetraisopropoxyzirconium, tetraisobutoxyzirconium, tetran-butoxyzaldehyde, tetrakis (2-ethylhexyloxy) zirconium, tetrakis (2-methyl-2-butoxy) zirconium, Tetra C _1-12 alkoxyzincyl, more preferably tetra C _1-6 alkoxyzincyl, etc.], titanium alkoxides [eg, tetramethoxytitanium, tetraethoxytitanium, tetrapropoxy, etc.], Titanium alkoxides [eg, tetramethoxytitanium, tetraethoxytitanium, tetrapropoxy, etc.] _{Tetra C 1-18} alkoxide titanium such as titanium, tetraisopropoxy titanium, tetra n-butoxy titanium, preferably tetra C _1-12 alkoxide titanium, more preferably tetra C _1-6 alkoxide titanium, etc.), these oligomers, etc.] , Metal alkoxides in which the metal corresponds to these alkoxides and the metal is the above-exemplified metal (metal other than titanium such as aluminum and zinc and zirconium). These hydrolyzable and condensable metal compounds may be used alone or in combination of two or more.

The metal oxide particles may be surface-treated (or surface-modified), if necessary, as described above. Examples of the surface treatment agent include hydrolyzable and condensable silicon compounds. Further, in the metal oxide particles obtained by hydrolysis condensation, a hydrolysis-condensable silicon compound and a hydrolysis-condensation metal compound may be combined and hydrolyzed and condensed. The hydrolyzable condensable silicon compounds, for example, dialkyl dialkoxy silanes (e.g., di-C _1-4 alkyl di C _1-4 alkoxysilane such as dimethyldimethoxysilane), alkylaryl dialkoxysilane (e.g., methyl phenyl dimethoxy silane _{C 1-4} alkyl _{-C 6-10} aryldi _{C 1-4} alkoxysilane) of diaryl dialkoxy silanes (e.g., _{di-C 6-10} aryldi _{C 1-4} alkoxysilane such as diphenyldimethoxysilane), alkyl Trialkoxysilane (eg C _1-4 alkyltri C _1-4 alkoxysilane such as methyltrimethoxysilane), _{aryltrialkoxysilane (eg C 6-10} aryltri C _1-4 alkoxy such as phenyltrimethoxysilane) Alkoxysilanes (or silicon alkoxys, such as di or trialkoxysilanes) such as silane) and the like can be mentioned.

These silicon compounds may be used alone or in combination of two or more.

When the metal oxide particles or the hydrolyzable condensable metal compound and the hydrolyzable condensable silicon compound are combined, the ratios thereof are the former / the latter (molar ratio) in terms of metal atoms (for example, zirconium atoms) and silicon atoms. ) = 1 / 0.1 to 1/2, for example, 1 / 0.15 to 1 / 1.5, preferably 1 / 0.2 to 1/1, and more preferably 1/0. It may be about .25 to 1 / 0.8.

The average particle size (average primary particle size) of the metal oxide particles is not particularly limited, but may be usually nanometer size. For example, the average volume particle size (cumulative 50% volume particle size) of the metal oxide particles can be selected from the range of 1000 nm or less (for example, 1 nm or more and 800 nm or less), and is 700 nm or less (for example, 1 nm or more and 600 nm or less), preferably. It may be 500 nm or less (for example, 2 nm or more and 400 nm or less), more preferably 300 nm or less (for example, 3 nm or more and 200 nm or less), particularly 100 nm or less (for example, 5 nm or more and 70 nm or less), and particularly sufficient transparency is ensured. In order to do so, it may be usually about 50 nm or less [for example, 1 nm or more and 40 nm or less, preferably 3 nm or more and 35 nm or less, and more preferably 30 nm or less (for example, 5 nm or more and 25 nm or less)].

Since the composition for dispersing metal oxide particles contains a silyl group-modified fluorene compound represented by the following formula (1), it usually keeps (or reflects) such a nanometer size. The metal oxide particles can be dispersed in the organic component (silyl group-modified fluorene compound represented by the formula (1) and the (meth) acrylate compound represented by the formula (2)).

The method for dispersing the metal oxide particles in the composition for dispersing the metal oxide particles is not particularly limited. For example, the composition for dispersing the metal oxide particles and the metal oxide particles are mixed to obtain the metal oxide particles into a metal. It may be dispersed in the composition for dispersing oxide particles.

The blending amount of the metal oxide particles is not particularly limited, but for example, the mass of the silyl group-modified fluorene compound represented by the above formula (1) with respect to 100 parts by mass of the metal oxide particles is 0.5 parts by mass or more and 100 parts by mass. It is preferably 1 part by mass or more and 50 parts by mass or less, and further preferably 2 parts by mass or more and 10 parts by mass or less.

The high refraction material may contain an organic solvent. However, in order to apply the inkjet method, it is preferable that the content of the organic solvent is small.
Specific examples of the organic solvent that the highly refracting material may contain are the same as those exemplified as the organic solvent when the composition for dispersing metal oxide particles contains an organic solvent.

(Refractive index of highly refracting material)
A highly refracting material obtained by mixing and dispersing metal oxide particles in a composition for dispersing metal oxide particles preferably has a refractive index of 1.6 or more, more preferably 1.63 or more. It is more preferably .65 or more, particularly preferably 1.70 or more, and most preferably 1.75 or more.
The upper limit of the refractive index is not particularly limited, but may be, for example, 3 or less and 2.5 or less.
In the present invention, the refractive index is preferably the refractive index for light rays having a wavelength of 656 nm, and the refractive index is based on the conditions measured in the examples described later unless otherwise specified.
The viscosity of the highly refracting material is not particularly limited, but is preferably in the range of 300 cP (mPa · s) or less from the viewpoint of being applicable to the inkjet method described later. The viscosity of the highly refracting material is more preferably 60 mPa · s or less, and particularly preferably 30 mPa · s or less. There is no particular lower limit, but it is 0.1 mPa · s or more.
The above viscosity is a viscosity measured at 25 ° C. using an E-type viscometer.

<< Cured film forming method >>
A step of applying the high-refractive-index material (a mixture of the composition for dispersing metal oxide particles and metal oxide particles) onto a substrate to form a coating film (hereinafter, simply "coating film formation"). A cured film can be formed by a cured film forming method including a step of curing the coating film.
The cured film forming method preferably further includes a pattern forming step, specifically,
(1) The step of pressing the mold against the surface of the coating film to form a pattern on the coating film is further included (imprint method), or (2) the step of curing the coating film is performed by position-selective exposure. It is preferable that the coating film exposed in a position-selective manner is further developed to form a pattern (development method).
In the development method (2), the development can be carried out using an alkaline developer or a developer containing an organic solvent, but the development is more preferably carried out using a developer containing an organic solvent.

The base material (substrate or support) can be selected according to various applications, and for example, metals such as quartz, glass, optical film, ceramic material, vapor-deposited film, magnetic film, reflective film, Ni, Cu, Cr, and Fe. Substrate, paper, polymer substrate such as SOG (Spin On Glass), polyester film, polycarbonate film, polyimide film, TFT array substrate, PDP electrode plate, glass or transparent plastic substrate, conductive substrate such as ITO or metal, insulation There are no particular restrictions on the base material, silicon, silicon nitride, polysilicon, silicon oxide, semiconductor-made substrates such as amorphous silicon, and the like. Further, the shape of the base material is not particularly limited, and may be a plate shape or a roll shape. Further, as the base material, a light-transmitting or non-light-transmitting material can be selected depending on the combination with the mold and the like.

First, in the coating film forming step, for example, a contact transfer type coating device such as an inkjet, a roll coater, a reverse coater, or a bar coater, a spinner (rotary coating device), a dispenser, or a spray is placed on a substrate on which a cured film is to be formed. , Screen printing, a non-contact coating device such as a curtain flow coater can be used to apply a highly refractory material, and if necessary, the solvent can be removed by drying (prebaking) to form a coating film.
The thickness of the coating film is not particularly limited, but is preferably 10 nm or more and 50 μm or less, more preferably 50 nm or more and 30 μm or less, further preferably 100 nm or more and 10 μm or less, and 150 nm or more and 5 μm or less. Is particularly preferable.
The droplets piled up on the substrate, the highly refracting material embedded in the recesses of the substrate having irregularities, the highly refracting material filled in the recesses of the mold, and the like are also referred to as "coating film" for convenience.
Since the high refraction material can be suitably used for the inkjet method, the inkjet method can be applied when pattern formation is performed by the imprint method as described in (1) above.

When pattern formation is performed by the imprint method as in (1) above, a mold is pressed against the surface of the pattern forming layer in order to transfer the pattern to the coating film. As a result, a fine pattern previously formed on the pressing surface of the mold can be transferred to the coating film. Further, a high refraction material may be applied to a mold having a pattern and the substrate may be pressed against the substrate.
A light-transmitting mold can be pressed against the surface of the coating film and exposed from the back surface of the mold to cure the coating film. It is also possible to apply a highly refracting material on a light-transmitting substrate, press a mold against it, expose it from the back surface of the substrate, and cure the highly refracting material.

The mold material is not particularly limited, but may be any material having predetermined strength and durability. Specific examples of the light-transmitting molding material include glass, quartz, PMMA, polycarbonate resin, light-transparent resin such as polyethylene terephthalate (PET), transparent metal vapor deposition film, flexible film such as polydimethylsiloxane, and photocuring. Examples include a film and a metal film.

The non-light transmitting mold material is not particularly limited, but may be any material having a predetermined strength. Specific examples include ceramic materials, vapor-deposited films, magnetic films, reflective films, metal substrates such as Ni, Cu, Cr, and Fe, and substrates such as SiC, silicon, silicon nitride, polysilicon, silicon oxide, and amorphous silicon. It is not particularly restricted. Further, the shape of the mold is not particularly limited, and either a plate mold or a roll mold may be used. Roll molds are especially applied when continuous transfer productivity is required.

When pattern formation is performed by the imprint method as in (1) above, it is preferable that the mold pressure is 10 atm or less. By setting the mold pressure to 10 atm or less, the mold and the substrate are less likely to be deformed, and the pattern accuracy tends to be improved. It is also preferable because the pressurization is low and the device tends to be reduced. For the mold pressure, it is preferable to select a region where the uniformity of mold transfer can be ensured within a range where the residual film of the highly refracting material on the convex portion of the mold is reduced.
If a vacuum state is used as a pre-stage of the following exposure, it is effective in preventing air bubbles from being mixed in, suppressing a decrease in reactivity due to oxygen mixing, and improving the adhesion between the mold and the highly refracting material. Good. The preferred degree of vacuum during exposure is in ^{the range of 10 -1} Pa to normal pressure.

Then, the formed coating film can be cured. The curing method is not particularly limited as long as it can cure the highly refracting material, and preferably includes exposure and / or heating, and includes exposure.
The light source is not particularly limited in the exposure, and examples thereof include a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a xenon lamp, a carbon arc lamp, and an LED. Using such a light source, ArF excimer laser coating, KrF excimer laser, _{F 2} excimer laser, extreme ultraviolet (EUV), vacuum ultraviolet (VUV), electron beams, X-rays, soft X-ray, g-line, i-line The coating film can be exposed by irradiating with radiation or an electromagnetic wave such as h-ray, j-ray, or k-ray. The exposure to the coating film may be regioselective via a negative mask. Exposure dose varies depending on the composition of the high-refractive materials, for example preferably 10 mJ / cm ² or more 2000 mJ / cm ² or less, 100 mJ / cm ² or more 1500 mJ / cm ² and more preferably less, 200 mJ / cm ² or more 1200 mJ / cm ² or less is more preferable. The exposure illuminance varies depending on the composition of the highly refracting material, but is preferably in the range of ^{1 mW / cm 2} or more and 50 mW / cm ^{2 or less.}
The temperature at the time of heating is not particularly limited, and is preferably 180 ° C. or higher and 280 ° C. or lower, more preferably 200 ° C. or higher and 260 ° C. or lower, and particularly preferably 220 ° C. or higher and 250 ° C. or lower. The heating time is typically preferably 1 minute or more and 60 minutes or less, more preferably 10 minutes or more and 50 minutes or less, and particularly preferably 20 minutes or more and 40 minutes or less.

As in the development method of (2) above, the step of curing the coating film is performed by regioselective exposure, and the coating film exposed in a regioselective manner is developed and patterned. A membrane can be obtained.

In the developing step, the exposed coating film is developed with a developing solution to form a cured product patterned into a desired shape. The developing method is not particularly limited, and a dipping method, a spray method, a paddle method, a dynamic dispensing method and the like can be used.
Specific examples of the developing solution containing an organic solvent include alcohol solvents such as PE (propylene glycol monomethyl ether) or glycol ether solvents, ether solvents such as tetrahydrofuran, ester solvents such as butyl acetate, acetone, and methyl amyl ketone. Examples thereof include ketone solvents such as.
Specific examples of the alkaline developing solution include organic ones such as monoethanolamine, diethanolamine and triethanolamine, and aqueous solutions such as sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia and quaternary ammonium salts.

Then, if necessary, the cured product after exposure or the patterned cured product after development may be post-baked to further heat cure. The post-baking temperature is preferably 150 ° C. or higher and 270 ° C. or lower.

<< Hardened product >>
The cured product obtained by curing the high-refractive-index material (the composition for dispersing the metal oxide particles and the metal oxide particles mixed and dispersed) has excellent heat resistance and a high refractive index. Since the high refractive index and excellent heat resistance suppress the generation of outgas, the cured product is suitable for display applications and applications where the influence of outgas is large, such as a high refraction layer in OLED lighting and the like. ..
The refractive index of the cured product is preferably 1.6 or more, more preferably 1.63 or more, further preferably 1.65 or more, and particularly preferably 1.7 or more. Most preferably, it is 1.75 or more.
The upper limit of the refractive index is not particularly limited, but may be, for example, 3 or less and 2.5 or less.
When the cured product is a cured film, the thickness of the cured film is not particularly limited, but is preferably 10 nm or more and 50 μm or less, more preferably 50 nm or more and 30 μm or less, and 100 nm or more and 10 μm or less. It is more preferable, and it is particularly preferable that it is 150 nm or more and 5 μm or less.

<< Applications of cured products >>
The cured product is suitable as a transparent optical member having various high refractive indexes, which will be described below.
For example, the cured product has an excellent refractive index, excellent heat resistance, and suppresses the generation of outgas, and is therefore suitable as a high bending layer for display applications, OLED lighting, and the like. For example, it is suitable as a high refraction layer of OLED.
Further, since the cured product has an excellent refractive index, it is suitable as a transmissive transparent screen, a reflective transparent screen, or the like in a head-up display, a head-mounted display device, a projector, or the like.
Also, for various applications such as transparent optical members (lenses, microlenses, wafer level lenses, optical fibers, optical waveguides, prism sheets, holograms, high refraction films, retroreflective films), optical wiring members, optical members such as diffraction gratings, etc. Suitable.
Further, the cured product is, for example, a sealing material for an OLED display element, an OLED lighting, a hard coat, an insulating film, an antireflection film, an interlayer insulating film, a carbon hard mask, a display panel material (flattening film, pixels of a color filter). , Organic EL partition, spacer) and the like.
Further, the cured product is preferably used as a transparent film for covering metal wiring or the like in a display element such as a touch panel.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to these Examples.

(Synthesis Example 1) Synthesis of silyl group-modified fluorene compound represented by formula (1) 4.0 g of fluorene compound having an allyloxy group represented by the following formula (a) and (3-mercaptopropyl) trimethoxysilane ( In the presence of 3.4 g of MPTMS), 0.075 g of TPPS (triphenylphosphine triphenylborane) and 0.15 g of polymerization initiator (Omnirad 184, manufactured by IGM Resins BV, 1-hydroxycyclohexyl-phenylketone) By photoreacting in tetrahydrofuran (THF) at room temperature (reacting with 365 nm broadband light), 4.2 g of a silyl group-modified fluorene compound represented by the following formula (a1) was obtained (yield 61.7%). .. The NMR of the obtained crystal was measured to confirm that it was the desired product.

(Synthetic Comparative Example 1) Synthesis of silyl group-modified fluorene compound represented by the following formula (a2) 9,9-bis (4-hydroxy-3-methylphenyl) fluorene is 9,9-bis (4-hydroxyphenyl). Instead of fluorene, a silyl group-modified fluorene compound represented by the following formula (a2) was synthesized according to Synthesis Example 1 of Patent Document 1.

[Heat resistance evaluation 1]
The silyl group-modified fluorene compound represented by the formula (a1) obtained in Synthesis Example 1 and the silyl group-modified fluorene compound represented by the above formula (a2) obtained in Synthesis Comparative Example 1 were each extracted with hexane. The dried product was used as a sample.
The sample was heated from 40 ° C. to 500 ° C. at a heating rate of 10 ° C./min in a He atmosphere by the TG-DSC-MS method and outgas measurement was performed (temperature in the MS device was 300 ° C.), and the peak value of the outgas amount was measured. The temperature of was calculated. For the measurement, a TG-DSC device manufactured by NETZSCH and an MS device manufactured by JEOL Ltd. were used.
As a result, the temperature of the peak value of the silyl group-modified fluorene compound represented by the formula (a1) obtained in Synthesis Example 1 was 390.5 ° C. The peak temperature of the silyl group-modified fluorene compound represented by the above formula (a2) obtained in Synthesis Comparative Example 1 was 380.0 ° C.

(Example 1)
2 g of the silyl group-modified fluorene compound represented by the above formula (a1) as the silyl group-modified fluorene compound represented by the formula (1) and phenylphenyl acrylate as the (meth) acrylate compound represented by the formula (2). 8 g was mixed to obtain a composition for dispersing metal oxide particles.

(Comparative Example 1)
Metal oxide particle dispersion in the same manner as in Example 1 except that the silyl group-modified fluorene compound represented by the above formula (a1) was replaced with the silyl group-modified fluorene compound represented by the above formula (a2). The composition for use was obtained.

[Refractive index evaluation]
The refractive index of the metal oxide particle dispersion compositions obtained in Example 1 and Comparative Example 1 was measured at a temperature of 25 ° C. and 656 nm using a prism coupler (manufactured by Metricon). The results are shown in Table 1.

[Heat resistance evaluation 2]
The heat resistance of the metal oxide particle dispersion compositions obtained in Example 1 and Comparative Example 1 was evaluated by the following method.
First, the metal oxide particle dispersion compositions obtained in Example 1 and Comparative Example 1 were each applied to a silicon substrate by an inkjet method so as to have a thickness of 1 μm. Then, it was allowed to absorb moisture by leaving it for 24 hours in an environment of a temperature of 85 ° C. and a humidity of 85%.
Using each substrate before and after moisture absorption as a sample, use the TDS method (heat temperature desorption gas spectroscopy) to heat each substrate to 40 to 100 ° C. under vacuum conditions using a temperature desorption gas analyzer (manufactured by ESCO). The amount of outgas observed when heated was measured. When the amount of outgas at 100 ° C. after moisture absorption and before moisture absorption is 100, the amount of outgas after moisture absorption is 100 or more and 105 or less, and the amount of outgas after moisture absorption is more than 105. Was set to x, and the heat resistance was evaluated. The results are shown in Table 1.

[Dispersibility evaluation]
Obtained and 1g metal oxide particle dispersion compositions of Examples 1 and Comparative Example 1, as the metal oxide particles, the average particle diameter of 10 nm ZrO ₂ nanoparticles 10g of mixed and stirred, a high refractive material It was.
The obtained highly refracting material was visually observed to evaluate the dispersibility. Any Example 1 and Comparative Example 1, ZrO ₂ grains are uniformly dispersed, the dispersion state was good.

The composition for dispersing metal oxide particles of Example 1 containing the silyl group-modified fluorene compound represented by the formula (1) and the (meth) acrylate compound represented by the formula (2) has excellent heat resistance. It was possible to prepare a highly refracting material to which the inkjet method can be applied. On the other hand, the composition for dispersing metal oxide particles of Comparative Example 1 containing no silyl group-modified fluorene compound represented by the formula (1) has heat resistance as compared with the composition for dispersing metal oxide particles of Example 1. Was bad.
More specifically, since the silyl group-modified fluorene compound represented by the formula (1) contained in the composition for dispersing metal oxide particles of Example 1 has excellent heat resistance, the composition for dispersing metal oxide particles also described above. , Excellent heat resistance and less outgassing.
Further, since the composition for dispersing metal oxide particles of Example 1 does not contain an organic solvent, changes in the concentration of the contained components due to volatilization of the organic solvent, poor ejection, and deterioration of curing sensitivity are suppressed, and the inkjet method is applied. I was able to.
In addition, the composition for dispersing metal oxide particles had good dispersibility of metal oxide particles and a high refractive index.

Claims

A composition for dispersing metal oxide particles, which comprises a silyl group-modified fluorene compound represented by the following formula (1) and a (meth) acrylate compound represented by the following formula (2).

(In the formula (1), the ring Z 1 represents a naphthalene ring and represents a naphthalene ring.
R 1a and R 1b independently represent a halogen atom, a cyano group or an alkyl group, respectively.
R 2a and R 2b each independently represent an alkyl group and represent an alkyl group.
R 3a and R 3b each independently represent an alkylene group and represent an alkylene group.
X a and X b each independently represent a group represented by -Si (OR 4 ) p (R 5 ) 3-p.
R 4 represents a hydrogen atom, an alkyl group or a group represented by- (R 6 O) q- R 7.
R 5 represents a hydrogen atom or a hydrocarbon group.
R 6 represents an alkylene group
R 7 represents an alkyl group
k1 and k2 independently represent integers of 0 or more and 4 or less, respectively.
m1 and m2 independently represent integers of 0 or more and 2 or less, respectively.
p represents an integer of 1 or more and 3 or less,
q represents an integer of 1 or more. )

(In formula (2), Z 2 represents an aromatic group containing two or more aromatic rings, R 8 represents a linear or branched alkylene group, R 9 represents a hydrogen atom or a methyl group, and r Represents an integer greater than or equal to 0.)
The composition for dispersing metal oxide particles according to claim 1, wherein the silyl group-modified fluorene compound represented by the formula (1) is a silyl group-modified fluorene compound represented by the following formula (1-1).

(In equation (1-1), R 1a , R 1b , R 2a , R 2b , R 3a , R 3b , X a , X b , R 4 , R 5 , R 6 , R 7 , k1, k2, m1 , M2, p and q are the same as those in the formula (1), respectively.)
Claim 1 in which the X a and X b are independently a trimethoxysilyl group, a triethoxysilyl group, a methyldimethoxysilyl group, an ethyldimethoxysilyl group, a methyldiethoxysilyl group, or an ethyldiethoxysilyl group. Or the composition for dispersing metal oxide particles according to 2.
The composition for dispersing metal oxide particles according to any one of claims 1 to 3, wherein r is 0.
The composition for dispersing metal oxide particles according to any one of claims 1 to 4, wherein Z 2 is a biphenyl group.
The composition for dispersing metal oxide particles according to any one of claims 1 to 5, which does not contain an organic solvent.
The composition for dispersing metal oxide particles according to claims 1 to 6, which contains a radical polymerization initiator.
The composition for dispersing metal oxide particles according to any one of claims 1 to 7 and the metal oxide particles are mixed, and the metal oxide particles are dispersed in the composition for dispersing metal oxide particles. A method of dispersing metal oxide particles.
The composition for dispersing the metal oxide particles and the metal oxide particles are mixed so that the mass of the silyl group-modified fluorene compound is 0.5 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the metal oxide particles. The method for dispersing metal oxide particles according to claim 8, wherein the metal oxide particles are mixed.