WO2022181321A1

WO2022181321A1 - Uv radiation sensitive member, microcapsule, microcapsule production method, liquid dispersion for forming uv radiation sensitive layer, and uv radiation sensitive kit

Info

Publication number: WO2022181321A1
Application number: PCT/JP2022/005017
Authority: WO
Inventors: 貴美池田
Original assignee: 富士フイルム株式会社
Priority date: 2021-02-26
Filing date: 2022-02-09
Publication date: 2022-09-01
Also published as: JPWO2022181321A1

Abstract

The present invention provides: a UV radiation sensitive member that exhibits superior sensitivity to the wavelength of 222 nm; microcapsules; a microcapsule production method; a liquid dispersion for forming a UV radiation sensitive layer; and a UV radiation sensitive kit. A UV radiation sensitive member according to the present invention comprises a UV radiation sensitive layer including microcapsules in which a photoactive agent, a color former, and a solvent have been encapsulated, wherein at least one of condition A and condition B is satisfied.

Description

UV sensing member, microcapsule, microcapsule manufacturing method, dispersion liquid for forming UV sensitive layer, UV sensing kit

The present invention relates to an ultraviolet sensing member, microcapsules, a method for producing microcapsules, a dispersion for forming an ultraviolet sensitive layer, and an ultraviolet sensing kit.

Measurement of the amount of ultraviolet rays is carried out in various fields. Specific examples include measurement of the amount of ultraviolet rays applied to an object to be irradiated during the curing reaction of an ultraviolet curable resin, and measurement of the amount of ultraviolet rays applied to an object to be irradiated during ultraviolet sterilization of foods and the like.
As a method for measuring the amount of ultraviolet rays, an ultraviolet photometer is used.
There are various types of ultraviolet light meters, such as ultraviolet light meters using semiconductor electromotive force and ultraviolet light meters using photochromics. For example, Patent Literature 1 discloses, as an ultraviolet photometer, an ultraviolet sensing member having an ultraviolet sensing layer containing capsules containing a color former and a photo-oxidizing agent.

WO2016/017701

Conventional ultraviolet sensing members are assumed to be used in the wavelength region of 300 nm or more. On the other hand, in recent years, deep ultraviolet rays in the wavelength range of 100 to 280 nm (for example, light emitted from low-pressure mercury lamps, light-emitting diodes, excimer lamps, etc.) are often used. .
The present inventors studied the ultraviolet sensing member described in Patent Document 1 and found that there is room for improvement in the sensitivity at a wavelength of 222 nm. Specifically, since the wavelength region to be measured is different in the conventional ultraviolet sensing member, when the conventional ultraviolet sensing member is irradiated with a wavelength of 222 nm at a predetermined integrated illuminance, the color cannot be sufficiently developed, and the coloring portion cannot be obtained. The color density had become low. In other words, the inventors have found that the sensitivity at a wavelength of 222 nm is inferior.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ultraviolet sensing member having excellent sensitivity at a wavelength of 222 nm.
Another object of the present invention is to provide microcapsules, a method for producing microcapsules, a dispersion for forming an ultraviolet sensitive layer, and an ultraviolet sensitive kit.

As a result of intensive studies aimed at solving the above problems, the inventors found that the problems can be solved by the configuration shown below, and completed the present invention.

[1]
An ultraviolet sensing member comprising an ultraviolet sensitive layer containing microcapsules encapsulating a photoactive agent, a coloring agent, and a solvent,
An ultraviolet sensing member that satisfies at least one of condition A and condition B.
Condition A: The solvent contains a non-aromatic solvent X having a heteroatom.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
[2]
The ultraviolet sensing member according to [1], wherein the solvent has a boiling point of 100° C. or higher.
[3]
[1 ] or the ultraviolet sensing member according to [2].
[4]
The non-aromatic solvent Z is one or more solvents selected from the group consisting of aliphatic hydrocarbons, aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. The ultraviolet sensing member according to any one of [1] to [3], comprising:
[5]
The ultraviolet sensing member according to any one of [1] to [4], wherein the aromatic solvent Y contains an aromatic solvent having a heteroatom.
[6]
the photoactive agent is a photooxidant,
The ultraviolet sensing member according to any one of [1] to [5], wherein the coloring agent is a coloring agent that develops color upon oxidation.
[7]
The photoactive agent is a photoacid generator,
The ultraviolet sensing member according to any one of [1] to [5], wherein the coloring agent is a coloring agent that develops color under the action of an acid.
[8]
The ultraviolet sensing member according to any one of [1] to [7], wherein the photoactive agent contains a compound represented by general formula (6).
R ³ -L ¹ -CX ³ X ⁴ X ⁵ (6)
In general formula (6), R ³ represents an optionally substituted aryl group or an optionally substituted heteroaryl group. L ¹ represents -SO- or -SO ₂ -. X ³ , X ⁴ and X ⁵ each independently represent a hydrogen atom or a halogen atom. However, the case where all of X ³ , X ⁴ and X ⁵ are hydrogen atoms is excluded.
[9]
The microcapsules do not contain an ultraviolet absorber having a benzotriazole structure, or
When the microcapsules contain an ultraviolet absorber having a benzotriazole structure, the content of the ultraviolet absorber having a benzotriazole structure is 1% by mass or less with respect to the total mass of the photoactive agent [1]. The ultraviolet sensing member according to any one of [8].
[10]
The ultraviolet sensing member according to any one of [1] to [9], which senses ultraviolet rays having a wavelength of 200 to 230 nm.
[11]
A microcapsule encapsulating a photoactive agent, a color former, and a solvent,
A microcapsule that satisfies at least one of condition A and condition B.
Condition A: The solvent contains a non-aromatic solvent X having a heteroatom.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
[12]
The microcapsules of [11], wherein the solvent has a boiling point of 100° C. or higher.
[13]
[11 ] or the microcapsule according to [12].
[14]
The non-aromatic solvent Z is one or more solvents selected from the group consisting of aliphatic hydrocarbons, aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. Microcapsules according to any one of [11] to [13].
[15]
The microcapsule according to any one of [11] to [14], wherein the aromatic solvent Y contains an aromatic solvent having a heteroatom.
[16]
the photoactive agent is a photooxidant,
The microcapsule according to any one of [11] to [15], wherein the coloring agent is a coloring agent that develops color upon oxidation.
[17]
The photoactive agent is a photoacid generator,
The microcapsule according to any one of [11] to [15], wherein the coloring agent is a coloring agent that develops color under the action of an acid.
[18]
The microcapsule according to any one of [11] to [17], wherein the photoactive agent contains a compound represented by general formula (6).
R ³ -L ¹ -CX ³ X ⁴ X ⁵ (6)
In general formula (6), R ³ represents an optionally substituted aryl group or an optionally substituted heteroaryl group. L ¹ represents -SO- or -SO ₂ -. X ³ , X ⁴ and X ⁵ each independently represent a hydrogen atom or a halogen atom. However, the case where all of X ³ , X ⁴ and X ⁵ are hydrogen atoms is excluded.
[19]
[11] A method for producing a microcapsule according to any one of [18],
mixing the color former, the photoactive agent, the solvent, and the emulsifier in water to prepare an emulsion;
forming a resin wall around the oil droplets containing the coloring agent, the photoactive agent, and the solvent in the emulsified liquid obtained in the above step for encapsulation to form the microcapsules. , a method for producing microcapsules.
[20]
[11] A dispersion for forming an ultraviolet-sensitive layer, comprising the microcapsules of any one of [11] to [18].
[21]
An ultraviolet sensing kit comprising the ultraviolet sensing member according to any one of [1] to [10].

According to the present invention, it is possible to provide an ultraviolet sensing member with excellent sensitivity to a wavelength of 222 nm.
Further, according to the present invention, it is possible to provide microcapsules, a method for producing microcapsules, a dispersion for forming an ultraviolet sensitive layer, and an ultraviolet sensitive kit.

1 is a schematic cross-sectional view showing an example of an embodiment of an ultraviolet sensing member of the present invention; FIG.

The present invention will be described in detail below.
In addition, although description of the constituent elements described below may be made based on a representative embodiment of the present invention, the present invention is not limited to such an embodiment.
In this specification, a numerical range represented by "to" means a range including the numerical values before and after "to" as lower and upper limits.
Further, in the numerical ranges described stepwise in this specification, the upper limit or lower limit described in a certain numerical range may be replaced with the upper limit or lower limit of the numerical range described in other steps. good. Moreover, in the numerical ranges described in this specification, the upper limit or lower limit described in a certain numerical range may be replaced with the values shown in the examples.
Further, in this specification, the solid content means a component that forms a composition layer formed using the composition, and when the composition contains a solvent (for example, an organic solvent, water, etc.), the solvent is means all ingredients except In addition, as long as it is a component that forms a composition layer, a liquid component is also regarded as a solid content.
Further, in this specification, ultraviolet light means light with a wavelength range of 10 to 400 nm.
Moreover, in this specification, (meth)acryl means "at least one of acryl and methacryl".
Moreover, in this specification, the "boiling point" means the boiling point at standard atmospheric pressure.

[Ultraviolet Sensing Member]
The UV-sensitive member of the present invention is a UV-sensitive member provided with a UV-sensitive layer containing microcapsules encapsulating a photoactive agent, a coloring agent and a solvent, and satisfies at least one of Condition A and Condition B.
Condition A: The solvent contains a non-aromatic solvent X with heteroatoms.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
Hereinafter, a solvent that satisfies at least one of condition A and condition B is also referred to as a "specific solvent".

Although the detailed mechanism by which the ultraviolet sensing member of the present invention having such a configuration has excellent sensitivity at a wavelength of 222 nm is not clear, the present inventors presume as follows.

When the ultraviolet sensitive layer of the ultraviolet sensitive member of the present invention is irradiated with ultraviolet rays when measuring the amount of ultraviolet rays, in the area irradiated with ultraviolet rays (ultraviolet irradiated area), the amount of ultraviolet rays (e.g., integrated illuminance) A colored portion (colored image) is formed with the color density. Developing a color with a color density corresponding to the amount of ultraviolet rays means that the colored image has gradation according to the amount of ultraviolet rays.

The above-mentioned main coloring mechanism of the UV-sensitive layer originates from the microcapsules contained in the UV-sensitive layer. When the UV-sensitive layer is irradiated with UV rays, the coloring agent usually develops color within the microcapsules present in the UV-irradiated region. For example, the photoactive agent absorbs ultraviolet rays and is activated to generate acid and/or radicals, and the color former reacts with the acid and/or radicals to develop color. At this time, the amount of acid and/or radicals generated from the photoactive agent varies depending on the amount of irradiated ultraviolet rays. The amount is also different. As a result, in the ultraviolet-irradiated region of the ultraviolet-sensitive layer, the color density varies depending on the amount of ultraviolet rays applied, and a colored portion is formed with a color-developed density corresponding to the amount of ultraviolet rays.

A feature of the ultraviolet sensitive member of the present invention is that the microcapsules in the ultraviolet sensitive layer contain a photoactive agent, a coloring agent, and a specific solvent.

The present inventors found that when the microcapsules in the ultraviolet sensitive layer contain a specific solvent, the specific solvent has less absorption at a wavelength of 222 nm, and the specific solvent has a high solubility of the photoactive agent and the color former, resulting in color development. Since it is difficult to inhibit the reaction, it is presumed that it contributes to the improvement of the sensitivity at a wavelength of 222 nm.
In addition, the UV-sensitive member of the present invention has excellent sensitivity at a wavelength of 222 nm, and is resistant to so-called fogging, which is colored by unexpected light (wavelength region other than the target measurement wavelength region) such as fluorescent lamps. I found out. It is presumed that when the microcapsules contained in the UV-sensitive layer enclose a specific solvent, the specific solvent controls the color-developing reaction, thereby making fogging less likely to occur.
Hereinafter, the more excellent sensitivity of the ultraviolet sensing member to a wavelength of 222 nm is also referred to as "the effect of the present invention is more excellent".

Hereinafter, embodiments of the ultraviolet sensing member of the present invention will be described in detail with reference to the drawings.

[First embodiment]
FIG. 1 is a schematic cross-sectional view of one embodiment of an ultraviolet sensing member.
The UV sensitive member 10 comprises a support 12 and a UV sensitive layer 14 disposed on one surface of the support 12 and containing microcapsules containing a photoactive agent, a coloring agent and a specific solvent. In the ultraviolet sensing layer 14 irradiated with ultraviolet rays, a coloring portion (not shown) is formed with a coloring density corresponding to the amount of ultraviolet rays.
Although FIG. 1 shows an embodiment in which the ultraviolet sensing member is sheet-shaped, the ultraviolet sensing member is not limited to this embodiment, and various shapes such as a block shape such as a rectangular parallelepiped and a columnar shape can be used as the shape of the ultraviolet sensing member. is. Among them, a sheet-like ultraviolet sensing member (ultraviolet sensing sheet) is preferably used.
As for the shape of the sheet-shaped ultraviolet sensing member, various shapes such as square, rectangle, circle, ellipse, polygon other than quadrangle such as hexagon, and irregular shape can be used. Also, the sheet-like ultraviolet sensing member may be elongated.

As will be described later, the ultraviolet sensitive member 10 may have the ultraviolet sensitive layer 14 and may not have the support 12 .
Furthermore, the ultraviolet sensitive member 10 shown in FIG. 1 has a two-layer structure of the support 12 and the ultraviolet sensitive layer 14, but it is not limited to this aspect, and as described later, other layers than the support 12 and the ultraviolet sensitive layer 14 are formed. Other layers (eg, reflective layer, gloss layer, filter layer, etc.) may be provided.

The lower limit of the thickness of the ultraviolet sensing member 10 is preferably 5 μm or more, more preferably 25 μm or more. Also, the upper limit is preferably 1 cm or less, more preferably 2 mm or less.
Each member of the ultraviolet sensing member will be described in detail below.

<<Support>>
A support is a member for supporting the ultraviolet sensitive layer.
If the ultraviolet sensitive layer itself can be handled, the ultraviolet sensitive member may not have a support.

Examples of the support include resin sheets, paper (including synthetic paper), cloth (including woven fabric and non-woven fabric), glass, wood, and metal. The support is preferably a resin sheet or paper, more preferably a resin sheet or synthetic paper, and still more preferably a resin sheet.
Materials for the resin sheet include polyethylene-based resin, polypropylene-based resin, cyclic polyolefin-based resin, polystyrene-based resin, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, polyvinyl chloride-based resin, fluorine-based resin, Poly(meth)acrylic resins, polycarbonate resins, polyester resins (polyethylene terephthalate, polyethylene naphthalate, etc.), various polyamide resins such as nylon, polyimide resins, polyamideimide resins, polyarylphthalate resins, silicone resins, polysulfone-based resins, polyphenylene sulfide-based resins, polyethersulfone-based resins, polyurethane-based resins, acetal-based resins, and cellulose-based resins.
Synthetic paper includes biaxially stretched polypropylene or polyethylene terephthalate or the like to form a large number of microvoids (Yupo, etc.), synthetic paper made using synthetic fibers such as polyethylene, polypropylene, polyethylene terephthalate, and polyamide, and Examples include a part of paper, or a product laminated on one side or both sides of the paper.

Another preferred embodiment of the resin sheet is a white resin sheet in which a white pigment is dispersed in a resin. Examples of the material of the resin in the white resin sheet include the same materials as those of the resin sheet described above.
The white resin sheet has UV reflectivity. Therefore, when the support is a white resin sheet, the ultraviolet rays irradiated to the ultraviolet sensing member are reflected by the support, so that scattering of the ultraviolet rays inside the ultraviolet sensing member can be suppressed. As a result, the detection accuracy of the amount of ultraviolet rays of the ultraviolet sensing member can be further improved.

As the white pigment, reference can be made to the white pigment described in paragraph 0080 of WO 2016/017701, the contents of which are incorporated herein.
As the white resin sheet, a white polyester sheet is preferable, and a white polyethylene terephthalate sheet is more preferable.
Commercially available white resin sheets include Yupo (manufactured by Yupo Corporation), Lumirror (manufactured by Toray Industries, Inc.), and Crisper (manufactured by Toyobo Co., Ltd.).

The lower limit of the thickness of the support is preferably 5 µm or more, more preferably 25 µm or more, and even more preferably 50 µm or more. The upper limit is preferably 1 cm or less, more preferably 2 mm or less, and even more preferably 500 μm or less.

<<Ultraviolet Sensing Layer>>
The UV-sensitive layer includes microcapsules (hereinafter also referred to as "specific microcapsules") encapsulating a photoactive agent, a coloring agent, and a specific solvent.
The various components that may be included in the UV sensitive layer are detailed below.

<Specific microcapsules>
The UV sensitive layer contains specific microcapsules.
First, the material constituting the specific microcapsules will be described in detail below.

A specific microcapsule usually has a core portion and a capsule wall for enclosing a core material forming the core portion (something to be encapsulated (hereinafter also referred to as “encapsulation component”)).
The specific microcapsules include a photoactive agent, a coloring agent, and a specific solvent as core materials (encapsulation components).

One preferred embodiment of the specific microcapsules is that the photoactive agent is a photooxidizing agent and the color former is a color former that develops color upon oxidation.
Another preferred embodiment of the specific microcapsules is that the photoactive agent is a photoacid generator and the color former is a color former that develops color under the action of acid.

As the specific microcapsule, it is preferable to prevent contact between substances inside and outside the capsule due to the substance isolation action of the capsule wall at room temperature. Specifically, JP-A-59-190886 and JP-A-60-242094 can be cited, the contents of which are incorporated herein.

(capsule wall)
It is preferred that the capsule walls of the specific microcapsules are substantially composed of resin. The phrase "substantially composed of resin" means that the resin content is 90% by mass or more, preferably 100% by mass, relative to the total mass of the capsule wall. In other words, the capsule walls of the specific microcapsules are preferably made of resin.
Examples of the resin include polyurethane, polyurea, polyester, polycarbonate, urea-formaldehyde resin, melamine-formaldehyde resin, polystyrene, styrene-methacrylate copolymer, gelatin, polyvinylpyrrolidone, and polyvinyl alcohol. Among them, from the group consisting of polyurea, polyurethane urea, and polyurethane, in that the sensitivity at a wavelength of 222 nm can be further improved by forming a dense crosslinked structure that prevents inclusions from leaking and by controlling the transmittance at a wavelength of 222 nm. More preferably, one or more selected.

Polyurea is a polymer having multiple urea bonds and is preferably a reaction product formed from raw materials including polyamine and polyisocyanate.
It should be noted that polyurea can be synthesized using polyisocyanate without using polyamine by utilizing the fact that a part of polyisocyanate reacts with water to form polyamine.
Polyurethane urea is a polymer having urethane bonds and urea bonds, and is preferably a reaction product formed from raw materials containing polyol, polyamine, and polyisocyanate.
Incidentally, when the polyol and the polyisocyanate are reacted, part of the polyisocyanate may react with water to form a polyamine, resulting in a polyurethane urea.
Polyurethane is a polymer having a plurality of urethane bonds, and is preferably a reaction product formed from raw materials containing polyol and polyisocyanate.

Polyisocyanate preferably has an aromatic ring or an alicyclic ring.
Among them, it is preferable that the polyisocyanate has an alicyclic ring from the viewpoint that the effects of the present invention are more excellent. When polyisocyanate having an alicyclic ring is used, the transparency of the microcapsule wall is excellent, so the sensitivity at a wavelength of 222 nm is more excellent.
Examples of the aromatic ring include aromatic hydrocarbon rings and aromatic heterocyclic rings, and aromatic hydrocarbon rings are preferably used.
The aromatic hydrocarbon ring may have a substituent.
The number of carbon atoms in the aromatic hydrocarbon ring is not particularly limited, but is preferably 6-30, more preferably 6-18, and even more preferably 6-10.
Aromatic hydrocarbon rings include, for example, benzene rings.

The number of aromatic rings in the polyisocyanate is not particularly limited, and may be one or two or more, preferably one.
The alicyclic ring may have a substituent.
Although the number of carbon atoms in the alicyclic ring is not particularly limited, it is preferably 3-30, more preferably 3-18, and even more preferably 6-10.
The alicyclic ring includes, for example, a cyclohexane ring.
The number of alicyclic rings in the polyisocyanate is not particularly limited, and may be 1 or 2 or more, preferably 1 to 3.

Aromatic polyisocyanates include aromatic diisocyanates such as m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxy-biphenyl diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, xylylene-1,4-diisocyanate, xylylene-1,3-diisocyanate, 4-chloroxylylene-1,3-diisocyanate, 2-methylxylylene-1,3-diisocyanate, 4,4'-diphenylpropane diisocyanate and 4,4'-diphenylhexafluoropropane diisocyanate.
Aliphatic polyisocyanates include aliphatic diisocyanates such as trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, butylene-1,2-diisocyanate, cyclohexylene-1,2-diisocyanate, cyclohexane sylene-1,3-diisocyanate, cyclohexylene-1,4-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,4-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatomethyl)cyclohexane, isophorone Diisocyanates, lysine diisocyanate, hydrogenated tolylene diisocyanate and hydrogenated xylylene diisocyanate.

Polyisocyanates also include tri- or higher functional polyisocyanates (eg, tri-functional triisocyanate and tetra-functional tetraisocyanate).
Trifunctional or higher polyisocyanates include adducts of aromatic or alicyclic diisocyanates and compounds having 3 or more active hydrogen groups in one molecule (for example, trifunctional or higher polyols, polyamines or polythiols). Tri- or more functional polyisocyanates (adduct type tri- or more functional polyisocyanates) and aromatic or alicyclic diisocyanate trimers (biuret type or isocyanurate type) are preferred.
Polyisocyanates also include formalin condensates of benzene isocyanate, polyisocyanates having polymerizable groups such as methacryloyloxyethyl isocyanate, and lysine triisocyanate.
Regarding polyisocyanate, "Polyurethane Resin Handbook" (edited by Keiji Iwata, published by Nikkan Kogyo Shimbun (1987)) can be cited.

Examples of commercially available polyisocyanates include Takenate (registered trademark) D-102, D-103, D-103H, D-103M2, P49-75S, D-110N, D-120N, D-140N, and D-160N. , D-127N, D-170N, D-170HN, D-172N, D-177N, D-204, D-165N, NP1100 (manufactured by Mitsui Chemicals) Sumidule N3300, Desmodur (registered trademark) L75, UL57SP, N3200, N3600, N3900, Z4470BA (manufactured by Sumika Bayer Urethane), Coronate (registered trademark) HL, HX, L, HK (manufactured by Nippon Polyurethane), P301-75E (manufactured by Asahi Kasei), Duranate (registered trademark) TPA -100, TKA-100, TSA-100, TSS-100, TLA-100, 24A-100, TSE-100 (manufactured by Asahi Kasei) and Barnock (registered trademark) D-750 (manufactured by DIC).

Polyols include, for example, aliphatic and aromatic polyhydric alcohols, hydroxypolyesters, and hydroxypolyalkylene ethers.
Specific examples include the polyols described in JP-A-60-049991, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 6-hexanediol, 1,7-hebutanediol, 1,8-octanediol, propylene glycol, 2,3-dihydroxybutane, 1,2-dihydroxybutane, 1,3-dihydroxybutane, 2,2-dimethyl- 1,3-propanediol, 2,4-pentanediol, 2,5-hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, dihydroxycyclohexane, diethylene glycol, 1,2,6 -trihydroxyhexane, 2-phenylpropylene glycol, 1,1,1-trimethylolpropane, hexanetriol, pentaerythritol, pentaerythritol ethylene oxide adduct, glycerin ethylene oxide adduct, glycerin, 1,4-di(2- hydroxyethoxy)benzene, condensation products of aromatic polyhydric alcohols such as resorcinol dihydroxyethyl ether and alkylene oxides, p-xylylene glycol, m-xylylene glycol, α,α'-dihydroxy-p-diisopropylbenzene, 4 ,4′-dihydroxy-diphenylmethane, 2-(p,p′-dihydroxydiphenylmethyl)benzyl alcohol, ethylene oxide adduct of bisphenol A, and propylene oxide adduct of bisphenol A.
The polyol is preferably used in such an amount that the ratio of hydroxyl groups is 0.02 to 2 mol per 1 mol of isocyanate groups.

Examples of polyamines include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, p-phenylenediamine, m-phenylenediamine, piperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, 2- Hydroxytrimethylenediamine, diethylenetriamine, triethylenetriamine, triethylenetetramine, diethylaminopropylamine, tetraethylenepentamine, and amine adducts of epoxy compounds.

Polyisocyanate can also react with water to form polymeric substances.

Polyisocyanates, polyols, and polyamines include, for example, US Pat. No. 3,281,383, US Pat. No. 3,773,695, US Pat. and Japanese Patent Publication No. 48-084086, the contents of which are incorporated herein.

The average particle size of the microcapsules is preferably 0.1 to 100 μm in terms of volume average particle size. The lower limit is more preferably 0.3 μm or more, and even more preferably 0.5 μm or more. The upper limit is more preferably 10 µm or less, and even more preferably 5 µm or less. When the average particle size (volume average particle size) of the microcapsules is 0.1 μm or more, the core material in the capsules can be more stably protected. On the other hand, when the average particle size (volume average particle size) of the microcapsules is 100 μm or less, the resolution of the colored image is further improved.
The average particle size (volume average particle size) of the microcapsules can be measured, for example, with a laser analysis/scattering particle size distribution analyzer LA950 (manufactured by Horiba, Ltd.).
When measuring the average particle size of the microcapsules contained in the ultraviolet sensing member, the average particle size (volume average particle size) of the microcapsules can be measured with a scanning electron microscope (SEM). Specifically, the surface of the ultraviolet sensitive layer is observed with an SEM at a magnification of 5000, and the average particle size of all microcapsules present in the observed field of view is determined by image analysis. If microcapsules cannot be observed on the surface, a cross-sectional slice is prepared and measured in the same manner as above.
In addition, the above-mentioned microcapsule means a concept including specific microcapsules and other than specific microcapsules.

(specific solvent)
A specific microcapsule encloses a specific solvent.
A specific solvent is a solvent that satisfies at least one of condition A and condition B.
Condition A: The solvent contains a non-aromatic solvent X with heteroatoms.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
"Aromatic solvent" means a solvent having an aromatic ring in the molecule. A "non-aromatic solvent" means a solvent that does not have an aromatic ring in its molecule.

・Non-aromatic solvent X
Non-aromatic solvent X is a non-aromatic solvent with heteroatoms.
The non-aromatic solvent X is not particularly limited as long as it has a heteroatom in its molecule and does not have an aromatic ring.

As the non-aromatic solvent X, a non-aromatic solvent having an aliphatic structure is preferred.
"Having an aliphatic structure" means having a hydrocarbon group having no aromatic ring in the molecule.
The aromatic ring-free hydrocarbon group may be linear, branched, or cyclic. In addition, in the above hydrocarbon group having no aromatic ring, carbon atoms in the hydrocarbon group may be substituted with heteroatoms and carbonyl carbon atoms. The hydrocarbon group may further have a substituent, and the substituent may have a heteroatom.
Examples of heteroatoms include atoms other than carbon atoms and hydrogen atoms, preferably nitrogen, oxygen, phosphorus, or sulfur atoms, and more preferably oxygen atoms.
The number of carbon atoms in the hydrocarbon group is not particularly limited, but is preferably 1-50, more preferably 6-50, and even more preferably 8-30.

The non-aromatic solvent X preferably contains one or more solvents selected from the group consisting of aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents.
In addition, the non-aromatic solvent X preferably contains an alcoholic solvent from the viewpoint of promoting the color-developing reaction. From the viewpoint of suitability for the encapsulation reaction, it is also preferable to contain one or more solvents selected from the group consisting of aliphatic carboxylic acids, fatty acid esters, ether solvents, amide solvents, and ketone solvents.

Examples of aliphatic carboxylic acids include oleic acid, dimethyl succinate, diethyl succinate, and methyl laurate.

Fatty acid esters include, for example, unsaturated fatty acid esters and saturated fatty acid esters. Specific examples include natural animal and vegetable oils such as soybean oil, corn oil, cottonseed oil, rapeseed oil, olive oil, coconut oil, castor oil, and fish oil.
Moreover, fatty acid esters include aliphatic carboxylic acid esters, aliphatic sulfonic acid esters, and aliphatic phosphate esters, and aliphatic phosphate esters are preferred. Specific examples of aliphatic phosphates include tri(2-ethylhexyl)phosphate.

Examples of ether-based solvents include propylene glycol monobutyl ether.

Examples of ketone-based solvents include cyclohexanone.

As the alcohol-based solvent, a long-chain alkyl alcohol is preferable, a long-chain alkyl mono-alcohol is more preferable, and a long-chain alkyl mono-alcohol having 6 to 20 carbon atoms is even more preferable, because it facilitates the capsule-forming reaction. Examples of long-chain alkyl monoalcohols having 6 to 20 carbon atoms include octanol.

Examples of amide-based solvents include N,N-diethyldodecanamide.

The boiling point of the non-aromatic solvent X is preferably 100°C or higher, more preferably 120°C or higher, and even more preferably 140°C or higher. Although the upper limit is not particularly limited, 500° C. or less is preferable. When the boiling point of the non-aromatic solvent X is 100° C. or higher, the specific solvent tends to remain without being removed from the specific microcapsules in the heating process such as the microencapsulation reaction.

The molecular weight of the non-aromatic solvent X is not particularly limited, and is often 100 or more, preferably 150 or more. Although the upper limit is not particularly limited, it is preferably 1000 or less, more preferably 600 or less, and even more preferably 500 or less.

The non-aromatic solvent X may be used alone or in combination of two or more.
The content of the non-aromatic solvent X in the specific microcapsules is preferably 1 to 100% by mass, more preferably 10 to 100% by mass, more preferably 15 to 100% by mass, relative to the total mass of the solvent. % by mass is more preferred.
The type, content, and composition ratio of the non-aromatic solvent X can be analyzed by extracting the UV-sensitive layer with acetone, concentrating the obtained filtrate, and performing GC-MS (Gas Chromatography Mass Spectrometry) analysis.

・Aromatic solvent Y
Aromatic solvent Y is an aromatic solvent having an aromatic ring.
The aromatic solvent Y may have heteroatoms. That is, the aromatic solvent Y may be an aromatic solvent having a heteroatom or may be an aromatic solvent having no heteroatoms. The aromatic solvent Y preferably has a heteroatom.

The aromatic ring of the aromatic solvent Y includes, for example, an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and the aromatic hydrocarbon ring is preferably used.
The aromatic hydrocarbon ring may be either a monocyclic ring or a condensed polycyclic ring, but is preferably a monocyclic ring.
Moreover, the aromatic hydrocarbon ring may have a substituent. When the aromatic hydrocarbon ring has a plurality of substituents, the substituents may bond together to form an alicyclic ring. Moreover, the aromatic hydrocarbon ring may have an aliphatic structure.
The number of carbon atoms in the aromatic hydrocarbon ring is not particularly limited, but is preferably 6-30, more preferably 6-18, and even more preferably 6-10.
Examples of the monocyclic aromatic hydrocarbon ring include a benzene ring.
Examples of polycyclic aromatic hydrocarbon rings include naphthalene rings.

The aromatic heterocyclic ring may be either monocyclic or polycyclic.
Moreover, the aromatic heterocyclic ring may have a substituent.
The number of aromatic rings in the aromatic solvent is not particularly limited, and may be one or two or more. In the case of containing two or more aromatic rings, the two aromatic rings form a polycyclic structure (but not including a condensed polycyclic structure) by binding to each other substituents that may be present on each aromatic ring. may be formed.

The heteroatom-containing aromatic solvent Y includes, for example, an aromatic solvent having an aromatic heterocycle in the molecule and an aromatic solvent having a heteroatom and an aromatic hydrocarbon ring in the molecule.
The heteroatom in the aromatic solvent Y having a heteroatom includes atoms other than carbon atoms and hydrogen atoms, preferably a nitrogen atom, an oxygen atom, a sulfur atom, or a phosphorus atom, more preferably an oxygen atom or a phosphorus atom. preferable. The heteroatom-containing aromatic solvent Y includes a carboxylate ester linking group, a sulfonate ester linking group, and a phosphate ester, in terms of ensuring the transmittance at a wavelength of 222 nm, promoting the color-developing reaction, and improving the sensitivity at a wavelength of 222 nm. It preferably contains one or more groups selected from the group consisting of a linking group, a carbonyl linking group, and a sulfone linking group.
Examples of heteroatom-containing aromatic solvents Y include substituted or unsubstituted benzenesulfonate esters such as methyl benzenesulfonate, ethyl benzenesulfonate, methyl toluenesulfonate, and ethyl toluenesulfonate; dimethyl phthalate; Substituted or unsubstituted phthalic acid diesters such as diethyl phthalate, dibutyl phthalate, dipentyl phthalate, dihexyl phthalate, and dicyclohexyl phthalate; triphenyl phosphate (TPP), tricresyl phosphate (TCP), trixylenyl phosphate (TXP), cresyl diphenyl phosphate (CDP), 2-ethylhexyl diphenyl phosphate (EHDP), t-butylphenyl diphenyl phosphate (t-BDP), bis-(t-butylphenyl) phenyl phosphate (BBDP), tris- aromatic phosphates such as (t-butylphenyl)phosphate (TBDP), isopropylphenyldiphenylphosphate (IPP), bis-(isopropylphenyl)diphenylphosphate (BIPP), and tris-(isopropylphenyl)phosphate (TIPP); be done.

The aromatic solvent Y may be used alone or in combination of two or more.
In the specific microcapsules, the content of the aromatic solvent Y is preferably more than 0% by mass and less than 100% by mass, more preferably 10 to 99% by mass, with respect to the total mass of the solvent, 20 More preferably, it is up to 95% by mass.
The boiling point and molecular weight of the aromatic solvent Y are the same as those of the non-aromatic solvent X described above, and the preferred embodiments are also the same.
The type, content and composition ratio of the solvent can be analyzed by the same method as the analysis method for the non-aromatic solvent X described above.

・Non-aromatic solvent Z
Non-aromatic solvent Z is a non-aromatic solvent.
The non-aromatic solvent Z may have heteroatoms. That is, the non-aromatic solvent Z may be a non-aromatic solvent with heteroatoms or a non-aromatic solvent without heteroatoms. The heteroatom-containing non-aromatic solvent Z is the same as the heteroatom-containing non-aromatic solvent X described above, and the preferred embodiments thereof are also the same.
Non-aromatic solvents Z without heteroatoms include, for example, aliphatic hydrocarbons.
The aliphatic hydrocarbon may be linear, branched, or cyclic.
The number of carbon atoms in the aliphatic hydrocarbon is preferably 1-50, more preferably 8-50, even more preferably 10-30.
Among them, the aliphatic hydrocarbons are preferably aliphatic hydrocarbons having 1 to 50 carbon atoms, more preferably branched aliphatic hydrocarbons having 8 to 50 carbon atoms.
The non-aromatic solvent Z is one or more solvents selected from the group consisting of aliphatic hydrocarbons, aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. preferably included.

Examples of the non-aromatic solvent Z include the above-mentioned non-aromatic solvent X, aliphatic hydrocarbons such as isoparaffins (e.g., isoparaffins having 10 to 30 carbon atoms), and natural high-boiling fractions such as mineral oils. mentioned.

The non-aromatic solvent Z may be used singly or in combination of two or more.
The content of the non-aromatic solvent Z in the specific microcapsules is preferably more than 0% by mass and less than 100% by mass, more preferably 1 to 50% by mass, relative to the total mass of the solvent, More preferably, it is 1 to 20% by mass.
The boiling point and molecular weight of the non-aromatic solvent Z are the same as those of the non-aromatic solvent X described above, and the preferred embodiments are also the same.
The type, content and composition ratio of the solvent can be analyzed by the same method as the analysis method for the non-aromatic solvent X described above.

The specific solvent preferably contains one or more solvents having a boiling point of 100° C. or higher, and more preferably all the specific solvents contained in the specific microcapsules have a boiling point of 100° C. or higher. In addition, as an upper limit of the boiling point of a specific solvent, 500 degrees C or less is preferable.
All solvents contained in the specific microcapsules preferably have a boiling point of 100° C. or higher. The upper limit of the boiling point of all solvents is preferably 500°C or less.

(color former)
A specific microcapsule encloses a coloring agent.
Here, the term "color former" refers to a compound that develops color from a substantially colorless state (colorless or weakly colored state) by acid and/or radicals generated from a photoactive agent. Point. A compound that develops color by reaction with an acid and/or a radical generated from a photoactive agent, which will be described later, is preferred.
The coloring agent is preferably a compound that develops color by oxidation or a compound that develops color by the action of an acid, and is preferably a leuco dye.
As the leuco dye, among others, it is a compound that develops color by being oxidized from a substantially colorless state (hereinafter also referred to as "oxidative coloring leuco dye"), or a compound that develops color from a substantially colorless state. A compound that develops color under the action of acid (hereinafter also referred to as "acid-color-forming leuco dye") is preferred.
Examples of leuco dyes include triarylmethanephthalide-based compounds, fluoran-based compounds, phenothiazine-based compounds, indolylphthalide-based compounds, azaindolylphthalide-based compounds, leuco auramine-based compounds, rhodamine lactam-based compounds, triarylmethanephthalide-based compounds, Examples include arylmethane-based compounds, diarylmethane-based compounds, triazene-based compounds, spiropyran-based compounds, thiazine compounds, and fluorene-based compounds.
For details of the above compounds, reference can be made to US Pat.
The coloring agents may be used singly or in combination of two or more.

Oxidative Color-Forming Leuco Dye One embodiment of the oxidation color-forming leuco dye is preferably a compound having one or two hydrogen atoms that develops color by removing electrons. Such oxidative chromogenic leuco dyes include, for example, (a) aminotriarylmethane, (b) aminoxanthine, (c) aminothioxanthine, and (d) as described in US Pat. No. 3,445,234. ) amino-9,10-dihydroacridine, (e) aminophenoxazine, (f) aminophenothiazine, (g) aminodihydrophenazine, (h) aminodiphenylmethane, (i) leukindamine, (j) aminohydrocinnamic acid (cyanethane, leucometine), (k) hydrazine, (l) leucoin digoid dye, (m) amino-2,3-dihydroanthraquinone, (n) tetrahalo-p,p'-biphenol, (o) 2-( p-hydroxyphenyl)-4,5-diphenylimidazole and (p) phenethylaniline. Among the above (a) to (p), (a) to (i) are colored by losing one hydrogen atom, and (j) to (p) are colored by losing two hydrogen atoms. develop color.

Among these, aminoarylmethanes are preferred, and aminotriarylmethanes are more preferred.
Aminotriarylmethane is preferably a compound represented by the following formula (L) or an acid salt thereof.

wherein Ar ¹ represents a phenyl group with R ¹ R ² N-substituents para to the bond to the methane carbon atom specified in formula (A1). Ar ² is a phenyl group having an R ¹ R ² N-substituent para to the bond to the methane carbon atom specified in formula (A1), or a phenyl group specified in formula (A2) ortho-position to the methane carbon atom, an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms), an alkoxy group (preferably an alkoxy group having 1 to 4 carbon atoms), a fluorine atom, a chlorine atom, and, represents a phenyl group having a substituent selected from the group consisting of bromine atoms; R ¹ and R ² each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a 2-hydroxyethyl group, a 2-cyanoethyl group or a benzyl group.
Ar ³ represents the same group as at least one of Ar ¹ and Ar ² , or represents a group different from Ar ¹ and Ar ² . When Ar ³ represents a group different from Ar ¹ and Ar ² , Ar ³ is (B1) a lower alkyl group (preferably an alkyl group having 1 to 4 carbon atoms), a lower alkoxy group (preferably 4 alkoxy groups), chlorine atom, diphenylamino group, cyano group, nitro group, hydroxy group, fluorine atom, bromine atom, alkylthio group, arylthio group, thioester group, alkylsulfonic acid group, arylsulfonic acid group, sulfonic acid a phenyl group optionally substituted with a substituent selected from the group consisting of a group consisting of a sulfonamide group, an alkylamide group, and an arylamide group; (B2) an amine group, a di-lower alkylamino group, and an alkylamino group; a naphthyl group optionally substituted with a substituent selected from the group consisting of (B3) a pyridyl group optionally substituted with an alkyl group, (B4) a quinolyl group, or (B5) substituted with an alkyl group represents an indolinylidene group.

In formula (L) above, R ¹ and R ² are preferably a hydrogen atom or alkyl having 1 to 4 carbon atoms.
In the above formula (L), Ar ¹ , Ar ² and Ar ³ are all R ¹ R ² N para to the bond to the methane carbon atom specified in formula (A1). It preferably represents a phenyl group having a -substituent, and more preferably the same group.

Specific examples of oxidation chromogenic leuco dyes include tris(4-dimethylaminophenyl)methane, tris(4-diethylaminophenyl)methane, bis(4-diethylaminophenyl)-(4-diethylamino-2-methylphenyl)methane, Bis(4-diethylamino-2-methylphenyl)-(4-diethylaminophenyl)methane, bis(1-ethyl-2-methylindol-3-yl)-phenylmethane, 2-N-(3-trifluoromethylphenyl )-N-ethylamino-6-diethylamino-9-(2-methoxycarbonylphenyl)xanthene, 2-(2-chlorophenyl)amino-6-dibutylamino-9-(2-methoxycarbonylphenyl)xanthene, 2-di benzylamino-6-diethylamino-9-(2-methoxycarbonylphenyl)xanthene, benzo[a]-6-N,N-diethylamino-9-(2-methoxycarbonylphenyl)xanthene, 2-(2-chlorophenyl)- amino-6-dibutylamino-9-(2-methylphenylcarboxamidophenyl)xanthene, 3,6-dimethoxy-9-(2-methoxycarbonyl)-phenylxanthene, benzoyl leucomethylene blue, and 3,7-bis- and diethylaminophenoxazine.

• Acid-color-forming leuco dye As one aspect of the acid-color-forming leuco dye, it is preferably a compound that develops color by donating electrons or accepting protons such as acids. Specific examples include compounds having partial skeletons such as lactones, lactams, sultones, spiropyrans, esters, and amides, and these partial skeletons are ring-opened or cleaved upon contact with acids or protons.
Leuco dyes that develop color under the action of acid (acid-color-forming leuco dyes) include, for example, 3,3-bis(2-methyl-1-octyl-3-indolyl)phthalide and 6′-(dibutylamino)-2′. -bromo-3′-methylspiro[phthalido-3,9′-xanthene], 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4- Azaphthalide, 3-(4-diethylamino-2-ethoxyphenyl)-3-(1-n-octyl-2-methylindol-3-yl)phthalide, 3-[2,2-bis(1-ethyl-2- methylindol-3-yl)vinyl]-3-(4-diethylaminophenyl)-phthalide, 2-anilino-6-dibutylamino-3-methylfluorane, 6-diethylamino-3-methyl-2-(2,6 -xylidino)-fluorane, 2-(2-chloroanilino)-6-dibutylaminofluorane, 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophthalide, 2-anilino-6-diethylamino-3 -methylfluorane, 9-[ethyl(3-methylbutyl)amino]spiro[12H-benzo[a]xanthene-12,1′(3′H)isobenzofuran]-3′-one, 2′-methyl-6 '-(Np-tolyl-N-ethylamino)spiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3-one, 3',6'-bis(diethylamino)-2- (4-Nitrophenyl)spiro[isoindole-1,9′-xanthene]-3-one, 9-(N-ethyl-N-isopentylamino)spiro[benzo[a]xanthene-12,3′-phthalide ], 2′-anilino-6′-(N-ethyl-N-isopentylamino)-3′-methylspiro[phthalide-3,9′-[9H]xanthene], and 6′-(diethylamino)-1 ',3'-dimethylfluorane can be mentioned.

(photoactivator)
A specific microcapsule encloses a photoactive agent.
The photoactive agent is not particularly limited as long as it is a compound that is activated by light, but the photoactive agent that is activated by light preferably acts on a color former to develop color, and is a compound that is activated by ultraviolet light. is preferably The photoactive agent is preferably one or more of a photooxidizing agent and a photoacid generator. When the specific microcapsules contain a color former that develops color by oxidation, the photoactive agent preferably contains a photo-oxidizing agent. Preferably, the agent comprises a photoacid generator.
In the specific microcapsules, the content ratio of the photoactive agent to the color former (photoactive agent/color former (mass ratio)) is preferably 0.1 to 30, and 0.1 to 30 in terms of better sensitivity. 3 to 20 is more preferred. When the photoactive agent is a photooxidant, the content ratio of the photoactive agent to the color former is preferably 0.4-3. The content ratio of the agents is preferably 3-20, more preferably 10-20.
The content ratio of the photoactive agent to the color former is obtained by extracting the ultraviolet-sensitive layer with methanol, using a mixture of methanol and water as the eluent, performing liquid chromatography analysis, and calculating the ratio at the maximum absorption wavelength of each component. can be analyzed with

Photo-oxidizing agent The photo-oxidizing agent is a compound that can be activated by ultraviolet rays to generate radicals and/or extract the hydrogen atoms of the coloring agent to color the coloring agent. preferable.
Among them, the photo-oxidizing agent is preferably one or more of radical generators and organic halogen compounds. A mode in which a radical generator and an organic halogen compound are used in combination as the photoacid generator is also preferred. When a radical generator and an organic halogen compound are used in combination, the ratio of the content of the radical generator to the organic halogen compound (radical generator/organic halogen compound (mass ratio)) is such that the gradation of the color-developing portion is more excellent. , preferably 0.1 to 10, more preferably 0.5 to 5.

.. Radical generator The radical generator is not particularly limited as long as it is a compound that is activated by ultraviolet rays to generate radicals.
As the radical generator, a hydrogen abstraction type radical generator is preferred. The hydrogen abstraction type radical generator has the effect of abstracting hydrogen atoms from the color former to promote oxidation of the color former.
Radical generators include, for example, the azide polymer described on page 55 of the 1968 Spring Research Presentation Meeting of the Photographic Society of Japan; 2-azidobenzoxazole, benzoylazide, and 2- Azide compounds such as azidobenzimidazole; 3′-ethyl-1-methoxy-2-pyridothiacyanine perchlorate and 1-methoxy-2-methylpyridinium p-toluene as described in US Pat. No. 3,615,568 sulfonates, etc.; lophine dimer compounds such as 2,4,5-triarylimidazole dimers described in JP-B-62-039728; benzophenones; p-aminophenyl ketones; polynuclear quinones;
Among them, one or more selected from lophine dimers and benzophenones are preferable, and lophine dimers are more preferable.
Rophine dimers include, for example, hexaarylbiimidazole compounds. As the hexaarylbiimidazole-based compound, the compounds described in paragraph 0047 of International Publication No. 2016/017701 can be considered, and the contents thereof are incorporated herein.
Among them, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole is preferred. Examples of 2,2′-bis(2-chlorophenyl)-4,4′,5,5′-tetraphenyl-1,2′-biimidazole include “B-IMD” (manufactured by Kurogane Kasei Co., Ltd.), And "B-CIM" (manufactured by Hodogaya Chemical Industry Co., Ltd.) can be used.

As lophine dimers, compounds represented by the following general formula (1) are also preferred.

wherein A, B, and D are each independently a carbocyclic or heteroaryl group that is unsubstituted or substituted with a substituent that does not inhibit the dissociation of the dimer to the imidazolyl group or the oxidation of the coloring agent. represents
B and D are each independently preferably unsubstituted or have 1 to 3 substituents, and A is unsubstituted or has 1 to 4 substituents is preferred.
Knowledge known as lophine dimers and the like can be used for the compounds represented by the general formula (1) and methods for producing them. See, for example, US Pat. No. 3,552,973 at column 4, line 22 and column 6, line 3, the contents of which are incorporated herein.

One type of radical generator may be used alone, or two or more types may be mixed and used.

..Organic halogen compound The organic halogen compound can accelerate the oxidation of the coloring agent.
As the organic halogen compound, a compound in which the number of halogen atoms in the molecule is 3 or more is preferable because the gradation of the color-developing portion is more excellent. The upper limit of the number of halogen atoms is preferably 9 or less. The organic halogen compounds are compounds other than lophine dimers and benzophenones.
An organic halogen compound may be used individually by 1 type, and may be used in mixture of 2 or more types.
Examples of organic halogen compounds include compounds represented by the following general formulas (2) to (7).

P ⁰ -CX ₃ (2)
In the formula, P ⁰ represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, or an optionally substituted aryl group. Each X independently represents a halogen atom.
Halogen atoms represented by P ⁰ and X include fluorine, chlorine, bromine and iodine atoms, preferably chlorine or bromine.
Examples of substituents that the alkyl group and aryl group represented by P ⁰ may have include a hydroxy group, a halogen atom, an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, an acetyl group, and , an alkoxy group having 1 to 6 carbon atoms, and the like.

Examples of compounds represented by the general formula (2) include trichloromethane, tribromomethane, carbon tetrachloride, carbon tetrabromide, p-nitrobenzotribromide, bromotrichloromethane, pensitrichloride, hexabromoethane, iodoform, 1,1,1-tribromo-2-methyl-2-propanol, 1,1,2,2-tetrabromoethane, 2,2,2-tribromoethanol, and 1,1,1-trichloro- 2-methyl-2-propanol can be mentioned.

In the formula, R represents a substituent. x represents an integer of 0 to 5;

Examples of substituents represented by R include a nitro group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, an acetyl group, a haloacetyl group, and a group having 1 to 3 carbon atoms. An alkoxy group is mentioned.
In addition, when two or more R exist in a formula, R may mutually be same or different.

An integer of 0 to 3 is preferable for x.

Examples of compounds represented by general formula (3) include o-nitro-α,α,α-tribromoacetophenone, m-nitro-α,α,α-tribromoacetophenone, p-nitro-α,α ,α-tribromoacetophenone, α,α,α-tribromoacetophenone, and α,α,α-tribromo-3,4-cycloacetophenone.

R ¹ -SO ₂ -X ¹ (4)

In the formula, R ¹ represents an optionally substituted alkyl group or an optionally substituted aryl group. X ¹ represents a halogen atom.

The alkyl group represented by R ¹ is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and even more preferably an alkyl group having 1 to 6 carbon atoms.
The aryl group represented by R ¹ is preferably an aryl group having 6 to 20 carbon atoms, more preferably an aryl group having 6 to 14 carbon atoms, and even more preferably an aryl group having 6 to 10 carbon atoms.
Examples of substituents that the alkyl group and aryl group represented by R ¹ may have include a nitro group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, an acetyl group, and a haloacetyl. and alkoxy groups having 1 to 3 carbon atoms.
The halogen atom represented by X ¹ includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a chlorine atom, a bromine atom or an iodine atom, more preferably a chlorine atom or a bromine atom.

Examples of compounds represented by general formula (4) include 2,4-dinitrobenzenesulfonyl chloride, o-nitrobenzenesulfonyl chloride, m-nitrobenzenesulfonyl chloride, 3,3′-diphenylsulfonedisulfonyl chloride, and ethanesulfonyl chloride. , p-bromobenzenesulfonyl chloride, p-nitrobenzenesulfonyl chloride, p-3-benzenesulfonyl chloride, p-acetamidobenzenesulfonyl chloride, p-chlorobenzenesulfonyl chloride, p-toluenesulfonyl chloride, methanesulfonyl chloride, and hensensulfonyl chloride. A bromide is mentioned.

R ² -SX ² (5)

In the formula, R ² represents an optionally substituted alkyl group or an optionally substituted aryl group. ^X2 represents a halogen atom.

The alkyl group optionally having substituent(s) and the aryl group optionally having substituent(s) represented by R ² have a substituent represented by R ¹ of general formula (4). is the same as an optionally substituted alkyl group and an optionally substituted aryl group, and preferred embodiments are also the same.
^The halogen atom represented by X2 includes a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a chlorine atom, a bromine atom or an iodine atom, more preferably a chlorine atom or a bromine atom.

Examples of compounds represented by general formula (5) include 2,4-dinitrobenzenesulfenyl chloride and o-nitrobenzenesulfenyl chloride.

R ³ -L ¹ -CX ³ X ⁴ X ⁵ (6)

In the formula, R ³ represents an optionally substituted aryl group or an optionally substituted heteroaryl group. L ¹ represents -SO- or SO ₂ -. X ³ , X ⁴ and X ⁵ each independently represent a hydrogen atom or a halogen atom. However, not all of X ³ , X ⁴ and X ⁵ are hydrogen atoms.

The aryl group represented by R ³ is preferably an aryl group having 6 to 20 carbon atoms, more preferably an aryl group having 6 to 14 carbon atoms, and even more preferably an aryl group having 6 to 10 carbon atoms.
The heteroaryl group represented by R ³ is preferably a heteroaryl group having 4 to 20 carbon atoms, more preferably a heteroaryl group having 4 to 13 carbon atoms, and still more preferably a heteroaryl group having 4 to 9 carbon atoms.
Examples of substituents that the aryl group and heteroaryl group represented by R ³ may have include a nitro group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, an acetyl group, A haloacetyl group and an alkoxy group having 1 to 3 carbon atoms are included.

The halogen atoms represented by X ³ , X ⁴ and X ⁵ include, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a chlorine atom, a bromine atom or an iodine atom. , a chlorine atom or a bromine atom are more preferred.

Examples of compounds represented by general formula (6) include hexabromodimethylsulfoxide, pentabromodimethylsulfoxide, hexabromodimethylsulfone, trichloromethylphenylsulfone, tribromomethylphenylsulfone (BMPS), trichloro-p- Chlorophenylsulfone, Tribromomethyl-p-nitrophenylsulfone, 2-Trichloromethylbenzothiazolesulfone, 4,6-Cymethylpyrimidine-2-tribromomethylsulfone, Tetrabromodimethylsulfone, 2,4-Dichlorophenyl-trichloromethylsulfone sulfone, 2-methyl-4-chlorophenyltrichloromethylsulfone, 2,5-dimethyl-4-chlorophenyltrichloromethylsulfone, 2,4-dichlorophenyltrimethylsulfone, and tri-p-tolylsulfonium trifluoromethanesulfonate; Trichloromethylphenylsulfone or tribromomethylphenylsulfone (BMPS) are preferred.

R ⁴ CX ⁶ X ⁷ X ⁸ (7)

In the formula, ^R4 represents an optionally substituted heteroaryl group. X ⁶ , X ⁷ and X ⁸ each independently represent a hydrogen atom or a halogen atom. However, not all of X ⁶ , X ⁷ and X ⁸ are hydrogen atoms.

The heteroaryl group represented by R ⁴ is preferably a heteroaryl group having 4 to 20 carbon atoms, more preferably a heteroaryl group having 4 to 13 carbon atoms, and still more preferably a heteroaryl group having 4 to 9 carbon atoms.
Examples of substituents that the heteroaryl group represented by R ⁴ may have include a nitro group, a halogen atom, an alkyl group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, an acetyl group, a haloacetyl group, An alkoxy group having 1 to 3 carbon atoms can be mentioned.
The halogen atoms represented by X ⁶ , X ⁷ and X ⁸ include, for example, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, preferably a chlorine atom, a bromine atom or an iodine atom. , a chlorine atom or a bromine atom are more preferred.

Examples of the compound represented by the general formula (7) include tribromoquinaldine, 2-tribromomethyl-4-methylquinoline, 4-tribromomethylpyrimidine, 4-phenyl-6-tribromomethylpyrimidine, 2 -trichloromethyl-6-nitrobenzothiazole, 1-phenyl-3-trichloromethylpyrazole, 2,5-ditribromomethyl-3,4-dibromothiophene, 2-trichloromethyl-3-(p-butoxystyryl)-1 ,3,4-oxadiazole, 2,6-didolychloromethyl-4-(p-methoxyphenyl)-triazine, and 2-(4-methylphenyl)-4,6-bis(trichloromethyl)-1 , 3,5-triazines.

Among them, as the organic halogen compound, the compound represented by the general formula (3), the compound represented by the general formula (6), or the compound represented by the general formula (7) is preferable, and the effect of the present invention is obtained. is more excellent, the compound represented by the general formula (6) is more preferable. Although the reason why the effect of the present invention is more excellent is not clear, it is presumed that the compound represented by the general formula (6) has good compatibility with the specific solvent and the wavelength of 222 nm.
The halogen atom contained in the above compound is preferably a chlorine atom, a bromine atom, or an iodine atom, and more preferably a chlorine atom or a bromine atom.

The organic halogen compounds may be used singly or in combination of two or more.

Photo-acid generator The photo-acid generator is preferably a compound that is cleaved by ultraviolet rays to generate an acid, and that can color the color former by the action of the acid.
Examples of the photoacid generator include nonionic photoacid generators and ionic photoacid generators, and nonionic photoacid generators are preferred because the effects of the present invention are more excellent. Examples of nonionic photoacid generators include organic halogen compounds and oxime compounds. Among them, organic halogen compounds are preferred in that the effects of the present invention are more excellent, and compounds represented by the above-described general formula (6). is more preferred.
As the organic halogen compound, a compound having 3 or more halogen atoms in the molecule is preferable because the gradation of the color-developing portion is more excellent. The upper limit of the number of halogen atoms is preferably 9 or less.
An organic halogen compound may be used individually by 1 type, and may be used in mixture of 2 or more types.
Specific examples of the organic halogen compound include the same organic halogen compounds mentioned as the photo-oxidizing agent in the upper section.

Ionic photoacid generators include diazonium salts, iodonium salts, and sulfonium salts, with iodonium salts or sulfonium salts being preferred. Examples of ionic photoacid color couplers include JP-A-62-161860, JP-A-61-67034, and JP-A-62-50382, the contents of which are incorporated herein.
The photoacid generator is not particularly limited as long as it is a compound that generates an acid upon exposure to light. Photoacid generators that generate inorganic acids such as hydrogen halide (e.g., hydrochloric acid), sulfuric acid, and nitric acid can be used. It may be a photoacid generator that generates organic acids such as carboxylic acid and sulfonic acid. Among them, a photo-acid generator that generates an inorganic acid is preferable, and a photo-acid generator that generates a hydrogen halide is more preferable, from the viewpoint that the effect of the present invention is more excellent.

Specific examples of photoacid generators include triarylsulfonium hexafluorophosphate, triarylsulfonium arsenate, triarylsulfonium antimonate, diaryliodonium hexafluorophosphate, diaryliodonium arsenate, diaryliodonium antimonate, and dialkylphenacyl. Sulfonium tetrafluoroborate, dialkylphenacylsulfonium hexafluorophosphate, dialkyl-4-hydroxyphenylsulfonium tetrafluoroborate, dialkyl-4-hydroxyphenylsulfonium hexafluorophosphate, N-bromosuccinimide, tribromomethylphenylsulfone, diphenyl iodine, 2-trichloromethyl-5-(p-butoxystyryl)-1.3.4-oxadiazole, and 2,6-ditrichloromethyl-4-(p-methoxyphenyl)-triazine .

(light stabilizer)
The specific microcapsules preferably enclose a light stabilizer.
The light stabilizer is not particularly limited as long as it is a material that is stabilized by light, but it preferably acts as a so-called free radical trapping substance that traps free radicals of the activated photoactive agent.
A light stabilizer may be used individually by 1 type, and may use 2 or more types.
Light stabilizers include, for example, 2,5-bis(1,1,3,3-tetramethylbutyl)hydroquinone, hydroquinone, catechol, resorcinol, and polyhydric phenols such as hydroxyhydroquinone, and o-amino Aminophenols such as phenol and p-aminephenol can be mentioned.
The content ratio of the light stabilizer to the photoactive agent (light stabilizer/photoactive agent (molar ratio)) is preferably 0.0001 to 100, more preferably 0.0001 to 10, and 0.0005 to 1. More preferred.

(reducing agent)
The specific microcapsules may enclose a reducing agent.
The reducing agent has the function of deactivating the photo-oxidizing agent.
When the specific microcapsules contain a reducing agent, a rapid change in the color density of the UV-sensitive layer due to UV irradiation can be suppressed, and the color density can be easily changed according to the amount of UV irradiation. A reducing agent may also function as an antioxidant.
One reducing agent may be used alone, or two or more reducing agents may be used in combination.
Examples of reducing agents include cyclic phenylhydrazide compounds. Specifically, 1-phenylpyrazolidin-3-one, 1-phenyl-4-methylpyrazolidin-3-one, 1-phenyl-4,4-dimethylpyrazolidin-3-one, 3- methyl-1-p-sulfophenyl-2-pyrazolin-5-one, 3-methyl-1-phenyl-2-pyrazolin-5-one, and 4-hydroxymethyl-4-methyl-1-phenyl-3- pyrazolidinone (Dimezone S, manufactured by Daito Kagaku Co., Ltd.) and the like.
As the reducing agent, the reducing agents described in paragraphs 0072 to 0075 of WO 2016/017701 can be considered, the contents of which are incorporated herein.

(Ultraviolet absorber)
The specific microcapsules may enclose an ultraviolet absorber.
Examples of ultraviolet absorbers include benzotriazole compounds (ultraviolet absorbers having a benzotriazole structure), benzophenone compounds, triazine compounds, and benzodithiol compounds.
Among them, it is preferable that the ultraviolet absorber has a small absorption at a wavelength of 222 nm because the sensitivity at a wavelength of 222 nm is more excellent. Specifically, triazine compounds, benzophenone compounds, and benzodithiol compounds are preferably used.
Moreover, it is preferable that the specific microcapsules do not enclose a benzotriazole compound having a large absorption at a wavelength of 222 nm. When the specific microcapsules encapsulate a benzotriazole compound, the content of the benzotriazole compound is preferably 1% by mass or less, more preferably 0.5% by mass or less, relative to the total mass of the photoactive agent. Although the lower limit is not particularly limited, it is, for example, 0.0001% by mass or more.
Moreover, the content of the benzotriazole compound is preferably 1% by mass or less, more preferably 0.5% by mass or less, relative to the total mass of the color former. Although the lower limit is not particularly limited, it is, for example, 0.0001% by mass or more.

Commercially available triazine compounds include, for example, Adekastab LA-F70 (manufactured by Adeka Co., Ltd.), Tinuvin 1577 ED, Tinuvin 1600 (manufactured by BASF), 2,4-Bis(2,4-dimethylphenyl)-6-(2- hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine, 2-(2,4-Dihydroxyphenyl)-4,6-diphenyl-1,3,5-triazine, and Ethylhexyl Triazone (Tokyo Kasei Co., Ltd. ) made).
Examples of commercially available benzophenone compounds include Chimassorb 81 and Chimassorb 81 FL (manufactured by BASF).
Benzodithiol compounds include, for example, compounds described in International Publication No. 2019/159570.

(other ingredients)
In addition to the components described above, the specific microcapsules may optionally contain one or more additives such as waxes, solvents other than the specific solvent, and odor inhibitors.

<Method for producing specific microcapsules>
The method for producing the specific microcapsules is not particularly limited, and examples thereof include known methods such as an interfacial polymerization method, an internal polymerization method, a phase separation method, an external polymerization method, and a coacervation method.

As a method for producing the specific microcapsules, for example, a method including an emulsification step and an encapsulation step shown below can be given as an example. In addition, in the encapsulation step, it is preferable to form a resin wall (capsule wall) by an interfacial polymerization method.
Emulsification step: A step of mixing a color former, a photoactive agent, a specific solvent, and an emulsifier in water to prepare an emulsion Encapsulation step: A color former in the emulsion obtained in the emulsification step, and light A process of forming a resin wall (capsule wall) around an oil droplet containing an active agent and a specific solvent for encapsulation

The interfacial polymerization method will be described below, taking as an example a method for producing specific microcapsules having a capsule wall made of polyurea or polyurethaneurea.
As the interfacial polymerization method, a photoactive agent, a specific solvent, a solvent containing an aliphatic structure having a boiling point of less than 100° C. (hereinafter also referred to as a “capsule preparation solvent”), a color former, and a capsule wall material (for example, a step of dispersing an oil phase containing polyisocyanate) in an aqueous phase containing an emulsifier to prepare an emulsion (emulsification step); and forming microcapsules (encapsulation step) encapsulating a photoactive agent selected from an oxidizing agent and a photoacid generator, a specific solvent, and a color former.

In the above emulsification step, the capsule-forming solvent is usually a component that can be added for the purpose of improving the solubility of the core material in the solvent. The capsule-forming solvent does not contain an aromatic ring in its molecule. In addition, the capsule-forming solvent is removed by a drying treatment in the method for forming an ultraviolet-sensitive layer, which will be described later. Therefore, it is preferable that the microcapsules in the ultraviolet sensing member do not contain a capsule-forming solvent.
The solvent for capsule preparation is not particularly limited, and examples thereof include ethyl acetate (boiling point 77°C), isopropyl acetate (boiling point 89°C), methyl ethyl ketone (boiling point 80°C), and methylene chloride (boiling point 40°C).
The capsule-forming solvent may be used alone or in combination of two or more.

Also, the type of emulsifier used in the emulsification step is not particularly limited, and examples thereof include dispersants and surfactants.
Dispersants include, for example, colloids that protect water-soluble polymers selected from known anionic polymers, nonionic polymers, and amphoteric polymers. Specifically, polyvinyl alcohol, gelatin, and , cellulose derivatives, and polyvinyl alcohol is preferably used.
The surfactant is preferably an anionic or nonionic surfactant such as alkylbenzenesulfonate (e.g. sodium dodecylbenzenesulfonate, ammonium dodecylbenzenesulfonate), alkylsulfonate (e.g. lauryl sodium sulfate, dioctyl sulfosuccinate sodium salt), and polyalkylene glycols (eg, polyoxyethylene nonylphenyl ether).

Also, as other methods for producing specific microcapsules, the methods described in the specifications of US Pat. Nos. 3,726,804 and 3,796,696 can be considered. The contents of which are incorporated herein.

The content of the specific microcapsules in the ultraviolet sensitive layer is not particularly limited, but is preferably 50 to 99% by weight, more preferably 60 to 90% by weight, based on the total weight of the ultraviolet sensitive layer.
The specific microcapsule content (solid content coating amount) in the ultraviolet sensitive layer is also preferably 0.1 to 30 g/m ² . The lower limit is preferably 0.5 g/m ² or more, more preferably 1 g/m ² or more. The upper limit is preferably 25 g/m ² or less, more preferably 20 g/m ² or less.

The UV-sensitive layer may contain components other than the specific microcapsules described above.
Other ingredients include, for example, polymeric binders, reducing agents, light stabilizers, cross-linking agents, sensitizers, UV absorbers, and surfactants.

Polymeric binders include polyvinyl alcohol, methylcellulose, ethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, gum arabic, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylate, and , ethicine-vinyl acetate copolymer and the like.
Further, as the polymer binder, the polymer binder described in paragraph 0078 of JP-A-2017-167155 can be considered, and the contents thereof are incorporated herein.
The polymeric binder may be crosslinked. In other words, the polymeric binder may be a crosslinked binder.
The cross-linking agent is not particularly limited, and for example, glyoxazole can be used. Also, the cross-linking agent described in paragraph 0079 of JP-A-2017-167155 can be considered. The contents of which are incorporated herein.

As reducing agents, sensitizers, surfactants, etc., JP-A-1-207741, page 9, lower left column to page 10, upper left column, paragraphs 0038 to 0039 of JP-A-2004-233614, and , 0048 to 0059, the contents of which are incorporated herein.
As the reducing agent, light stabilizer, UV absorber and surfactant, the reducing agent, light stabilizer, UV absorber and surfactant that can be contained in the specific microcapsules can also be used.

The mass (solid content coating amount) per unit area of the ultraviolet sensitive layer is not particularly limited, but is preferably 0.1 to 30 g/m ² , more preferably 0.5 to 25 g/m ² , more preferably 1 to 10 g/m 2 . More preferred is ^m2 .

The thickness of the ultraviolet sensitive layer is preferably 0.1-30 μm, more preferably 0.5-25 μm, and even more preferably 1-10 μm.

<Method for Forming Ultraviolet Sensing Layer>
A method for forming the ultraviolet-sensitive layer is not particularly limited, and includes known methods.
For example, there is a method in which a support is coated with a dispersion for forming an ultraviolet sensitive layer containing specific microcapsules, and the coated film is subjected to a drying treatment, if necessary.
The ultraviolet-sensitive layer-forming dispersion contains specific microcapsules. The microcapsule dispersion obtained by the interfacial polymerization method described above may be used as the dispersion for forming the ultraviolet sensitive layer.
The ultraviolet-sensitive layer-forming dispersion may contain other components that may be contained in the ultraviolet-sensitive layer described above.

The method of applying the dispersion for forming the ultraviolet sensitive layer is not particularly limited, and examples of coating machines used for coating include air knife coaters, rod coaters, bar coaters, curtain coaters, gravure coaters, and extrusion. Coaters, die coaters, slide bead coaters and blade coaters are included.

After applying the ultraviolet-sensitive layer-forming dispersion onto the support, the coating film may be subjected to a drying treatment, if necessary. Examples of the drying treatment include heat treatment.

In the above, the method of forming the UV-sensitive layer on the support is described, but it is not limited to the above-described mode. For example, after forming the UV-sensitive layer on the temporary support, peeling off the temporary support, A UV sensitive member may be formed comprising a UV sensitive layer.
The temporary support is not particularly limited as long as it is a peelable support.

<<Other Layers>>
The UV sensitive member may have layers other than the support and UV sensitive layer described above.
Other layers include, for example, a reflective layer, a gloss layer, a filter layer, and a sensitivity adjustment layer.

<Reflective layer>
The UV sensitive member may further comprise a reflective layer.
When the ultraviolet sensitive layer has a reflective layer, the ultraviolet ray irradiated to the ultraviolet ray sensitive member can be reflected by the layer having ultraviolet reflective properties, so that scattering of the ultraviolet ray inside the ultraviolet ray sensitive member can be suppressed, and the detection accuracy of the amount of ultraviolet rays can be improved. can be improved.
The reflective layer preferably has a reflectance of 10% or more, more preferably 50% or more, for light with a wavelength of 200 to 380 nm. The reflectance can be measured, for example, by diffuse reflectance measurement using an ultraviolet-visible spectrophotometer (UV-2700/Shimadzu Corporation).
When the support is arranged adjacent to the reflective layer, an adhesion layer may be provided between the support and the reflective layer.
As the reflective layer, the adhesion layer, and the production method thereof, the reflective layer, the adhesion layer, and the production method thereof described in paragraphs 0082 to 0091 of WO 2016/017701 can be referred to. The contents of which are incorporated herein.

<Gloss layer>
The UV sensitive member may further comprise a glossy layer.
When the UV-sensitive layer has a glossy layer, the front and back visibility can be improved.
As the glossy layer and its manufacturing method, the glossy layer and its manufacturing method described in paragraphs 0092 to 0094 of WO 2016/017701 can be referred to, and the contents thereof are incorporated herein.

<Filter layer>
Preferably, the UV sensitive member further comprises a filter layer.
A filter layer is a layer that selectively transmits light of a specific wavelength. Here, "selectively transmit light of a specific wavelength" means to transmit light of a specific wavelength and block other light. The transmittance of light having a wavelength to be transmitted is, for example, preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. For example, the transmittance of light having a wavelength to be blocked is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less.
The filter layer is preferably a filter layer that blocks light with a wavelength of 300 nm or more, and is also preferably a filter layer that blocks light with a wavelength of over 230 nm. An ultraviolet bandpass filter, a filter containing a dielectric, or the like is preferably used.
The spectral characteristics of the filter layer and the sensitivity adjustment layer described later can be measured using, for example, an ultraviolet-visible spectrophotometer (UV-2700/Shimadzu Corporation).
The filter layer preferably contains an ultraviolet absorber in order to block light of wavelengths other than the specific wavelength. A known ultraviolet absorber can be used as the ultraviolet absorber. In order to block light with a wavelength of more than 230 nm, the filter layer preferably contains an ultraviolet absorber that can be contained in the specific microcapsules.

As for the filter layer and its manufacturing method, the filter layer and its manufacturing method described in paragraphs 0016 to 0026 of International Publication No. 2016/017701 can be considered, and the contents thereof are incorporated herein.

<Sensitivity adjustment layer>
When the ultraviolet sensing member has a filter layer, it may further have a sensitivity adjusting layer on the surface of the filter layer.
As the sensitivity adjustment layer and its manufacturing method, reference can be made to the sensitivity adjustment layer and its manufacturing method described in paragraphs 0095 to 0109 of WO 2016/017701, and the contents thereof are incorporated herein.

[Other embodiments]
Embodiments of the ultraviolet sensing member are not limited to the embodiments described above.
As other embodiments other than the embodiments described above, for example, the aspects described in FIGS. 1 to 5 of WO 2016/017701 can be considered, and the contents thereof are incorporated herein. Moreover, as another embodiment, it may be in the form of a kit, which will be described later.
Alternatively, the specific microcapsules may be kneaded into a resin to form a molding. Examples of the resin include resins that can be used as a material for a resin sheet as a support.

[Characteristics and uses of ultraviolet sensing member]
The ultraviolet sensing member of the present invention can be colored according to the amount of ultraviolet rays, and the difference in color density of the colored portion can be visually confirmed. Moreover, when it is in a sheet form, it is possible to measure the amount of ultraviolet rays over a wide area.

In the ultraviolet sensing member, the slope of the straight line obtained by plotting the logarithm of the integrated illuminance of the light with a wavelength of 222 nm applied to the ultraviolet sensing member on the horizontal axis and the color density of the ultraviolet sensitive layer on the vertical axis is suitable for the desired application. It can be adjusted accordingly. For example, when the slope is gradual (in other words, when the gradation is gradual), it can be applied to a wide energy range. be able to.
When the slope γ is within the above range, the color gradation suitable for detecting the amount of ultraviolet light is obtained, and the difference in color density of the colored portion can be easily confirmed visually.
In this specification, "integrated illuminance" is integrated illuminance measured at a wavelength of 222 nm, and includes, for example, a value measured with a 222 nm wavelength UV illuminometer.
The "color density" is a numerical value defined by reflection density D=-log ₁₀ ρ (where ρ is reflectance), and can be measured, for example, with a reflection densitometer (X-Rite310, manufactured by X-Rite).

Moreover, the following method may be used as a method for measuring the difference in color density of the coloring portion.
After irradiating the UV-sensing member with a predetermined ultraviolet ray to develop a color, the obtained sheet is scanned with a scanner (eg, GT-F740/GT-X830, manufactured by Epson) or a reading device such as a smartphone. The image obtained by reading is analyzed for the density of the colored portion using a UV light quantity distribution analysis system (FUD-7010J, manufactured by Fuji Film Co., Ltd.). Note that correction processing and calibration processing may be performed as necessary.

The UV sensing member can be used, for example, to measure the amount of UV rays emitted from an UV irradiation device when manufacturing a sheet while UV-curable resin is UV-cured in a roll-to-roll manner. It is also possible to routinely measure the amount of ultraviolet rays during the day, for example, in order to grasp the degree of sunburn caused by ultraviolet rays on people and objects.
In recent years, an indoor sterilization device that sterilizes airborne bacteria and viruses in a manned environment and a sterilization device that sterilizes bacteria and viruses adhering to objects by irradiating ultraviolet rays have been developed. The sterilization device performs sterilization by irradiating ultraviolet rays (UV-C: ultraviolet-C) with a wavelength of 200 to 280 nm. Among them, in a manned environment, ultraviolet rays with a wavelength of 200 to 230 nm (in particular, 222 nm UV) is preferably used. It is also possible to measure the UV dose of such devices using the UV sensitive member of the present invention.

[Dispersion for forming ultraviolet sensitive layer and method for producing the same]
The present invention also relates to a dispersion liquid for forming an ultraviolet sensitive layer capable of forming the ultraviolet sensitive layer of the ultraviolet sensitive member described above and a method for producing the same.
The dispersion for forming an ultraviolet sensitive layer of the present invention is a dispersion for forming an ultraviolet sensitive layer containing microcapsules encapsulating a photoactive agent, a coloring agent and a specific solvent. That is, the dispersion for forming an ultraviolet-sensitive layer of the present invention corresponds to a dispersion containing the specific microcapsules described above.
The composition of the dispersion for forming an ultraviolet sensitive layer of the present invention will be described in detail below.

The dispersion for forming an ultraviolet sensitive layer of the present invention contains specific microcapsules. The specific microcapsules are the same as the specific microcapsules contained in the ultraviolet sensing member, and the preferred embodiments are also the same.
The content of the specific microcapsules in the ultraviolet-sensitive layer-forming dispersion is preferably 50 to 99% by mass, more preferably 60 to 90% by mass, based on the total solid content in the composition. preferable.

The dispersion for forming an ultraviolet sensitive layer of the present invention may contain other components than the specific microcapsules that can be contained in the ultraviolet sensitive layer. Other components include, for example, polymer binders, cross-linking agents (cross-linking agents for forming cross-linked polymer binders (eg, glyoxazole, etc.)), reducing agents, sensitizers, and surfactants. Specific examples of other components are as described above.
When the ultraviolet-sensitive layer-forming dispersion contains a polymeric binder, the content of the polymeric binder is preferably 1 to 50% by weight, preferably 5 to 40% by weight, based on the total solid content in the composition. %, more preferably 10 to 30% by mass.
When the ultraviolet-sensitive layer-forming dispersion contains a surfactant, the content of the surfactant is preferably 0.01 to 10% by mass, and 0.01 to 10% by mass, based on the total solid content in the composition. It is more preferably 1 to 5% by mass, even more preferably 0.2 to 2% by mass.

The method for producing the ultraviolet-sensitive layer-forming dispersion is not particularly limited, and includes, for example, the above-described method for producing the specific microcapsules. In other words, a manufacturing method including the above-described emulsification step and encapsulation step can be mentioned. The dispersion for forming the ultraviolet sensitive layer has a composition obtained by adding an optional component for forming the ultraviolet sensitive layer to the microcapsule dispersion obtained by the production method including the emulsification step and the encapsulation step described above. It is preferably an object.

[Ultraviolet Sensing Kit]
The present invention also relates to a UV sensing kit comprising the UV sensing member described above.
The ultraviolet sensing kit includes at least the ultraviolet sensing member described above.
The specific configuration of the UV sensing kit is not particularly limited. sheet, more preferably a filter sheet that blocks light with a wavelength of more than 230 nm), a light shielding bag (ultraviolet cut bag), a judgment sample, a limit sample (calibration sheet), a condensing jig such as a lens and a concave mirror, and an ultraviolet sensing member and another element selected from the group consisting of a holding member that holds a.
The holding member may have an opening for irradiating the ultraviolet sensing member held with ultraviolet rays, or the holding member and the judgment sample may be integrated.

The present invention will be described in more detail based on examples below.
The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the gist of the present invention. Therefore, the scope of the present invention should not be construed to be limited by the examples shown below. In the following, "parts" and "%" are based on mass unless otherwise specified.

[Production of UV Sensing Member]
[Example 1]
Mixture 1 having the following composition was added to a 5% by mass polyvinyl alcohol aqueous solution (202 parts), and then emulsified and dispersed at 20° C. to obtain an emulsion having a volume average particle size of 1 μm. Furthermore, the obtained emulsion was kept stirring at 50° C. for 4 hours. After that, the mixture was returned to room temperature and filtered to obtain an aqueous capsule dispersion.

<Composition of mixed solution 1>
Color former: Leuco Crystal Violet (trade name “LCV”, manufactured by Yamada Chemical Co., Ltd.), 2.5 parts Organic halogen compound: Tribromomethylphenylsulfone (BMPS, manufactured by Sumitomo Seika Co., Ltd.), 1.25 parts Radical generator : Rofein dimer (2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, trade name "B-IMD", Kurogane Kaseisha ), 2.5 parts Non-aromatic solvent X and Z: soybean oil (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 15 parts Aromatic solvent Y: tricresyl phosphate (TCP, manufactured by Daihachi Chemical Co., Ltd.) , 15 parts Capsule preparation solvent: ethyl acetate (manufactured by Showa Denko Co., Ltd.), 50 parts light stabilizer: 2,5-bis (1,1,3,3-tetramethylbutyl) hydroquinone (BTHQ, Tokyo Chemical Industry Co., Ltd.), 0.03 parts Capsule wall material: polyisocyanate (trade name “Takenate D-110N”, manufactured by Mitsui Chemicals, Inc.), 31 parts

Obtained capsule dispersion (20 parts), polyvinyl alcohol 6 mass% aqueous solution (trade name “Denkasize EP-130”, manufactured by Denka Co., Ltd.) (5 parts), glyoxal (manufactured by Daito Kagaku Co., Ltd.) 0.05 part and a 50% by mass aqueous solution of sodium dodecylbenzenesulfonate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) (0.09 parts) to prepare a dispersion for forming an ultraviolet sensitive layer (coating liquid for forming an ultraviolet sensitive layer). did.

The resulting coating solution for forming an ultraviolet sensitive layer was applied to a 75 μm thick white polyethylene terephthalate film (trade name “Crisper K1212” manufactured by Toyobo Co., Ltd.) so that the solid content coating amount was 5 g/m ² , and heated to 105°C. It was dried by heating for 1 minute to prepare an ultraviolet sensitive member comprising a support and an ultraviolet sensitive layer. The UV sensitive layer was about 5 μm.

[Example 2]
An ultraviolet sensing member was produced in the same manner as in Example 1, except that mixed solution 1 was changed to mixed solution 2 having the following composition.
<Composition of mixed solution 2>
Color former: 3,3-bis (2-methyl-1-octyl-3-indolyl) phthalide (manufactured by BASF), 2.5 parts Organic halogen compound: tribromomethylphenylsulfone (BMPS, Sumitomo Seika Co., Ltd.) ), 1.25 parts Non-aromatic solvents X and Z: soybean oil (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 15 parts Aromatic solvent Y: tricresyl phosphate (TCP, manufactured by Daihachi Chemical Co., Ltd.) , 15 parts Capsule preparation solvent: ethyl acetate (manufactured by Showa Denko Co., Ltd.), 50 parts light stabilizer: 2,5-bis (1,1,3,3-tetramethylbutyl) hydroquinone (BTHQ, Tokyo Chemical Industry Co., Ltd.), 0.03 parts Polyisocyanate: (trade name “Takenate D-110N”, manufactured by Mitsui Chemicals), 31 parts

[Examples 3, 7, 9, 11, 13, 15, 17]
Ultraviolet sensing members of Examples 3, 7, 9, 11, 13, 15 and 17 were produced in the same manner as in Example 1 except that the components and formulations shown in Table 1 were changed.

[Examples 4, 8, 10, 12, 14, 16, 18]
Ultraviolet sensing members of Examples 4, 8, 10, 12, 14, 16, and 18 were produced in the same manner as in Example 2, except that the components and formulations shown in Table 1 were changed.

[Example 5]
An ultraviolet sensing member of Example 5 was produced in the same manner as in Example 1, except that the components and formulations were changed to those shown in Table 1 and the stirring conditions were changed to 50° C. for 8 hours.

[Example 6]
An ultraviolet sensing member of Example 6 was produced in the same manner as in Example 2, except that the components and formulations were changed to those shown in Table 1 and the stirring conditions were changed to 50° C. for 8 hours.

[Example 19]
The ultraviolet sensing member of Example 19 was prepared in the same manner as in Example 2 except that the components and formulations were changed to those shown in Table 1 and the amount of the 6% by mass polyvinyl alcohol aqueous solution added to the capsule dispersion was changed to 7 parts. was made.

[Comparative Example 1]
Comparative Example 1 refers to Example 1 of International Publication No. WO 2016/017701, and the ultraviolet sensing member of Comparative Example 1 is manufactured in the same manner as in Example 1 except that the components and formulations shown in Table 1 are changed. was made.

Table 1 is shown below.
In addition, each component shown in Table 1 is as follows.

<Non-Aromatic Solvents Z and X>
・Soybean oil (boiling point 300°C or higher)
・Oleic acid (boiling point 360°C)
・Diethyl succinate (boiling point 217°C)
・Methyl laurate (boiling point 141°C)
・Rapeseed oil (boiling point 300°C or higher)
・Triethylhexyl phosphate (tri(2-ethylhexyl)phosphate, boiling point 300°C or higher)

<Non-aromatic solvent Z>
・ Isoparaffin: Synthetic isoparaffin (manufactured by Idemitsu Kosan Co., Ltd., IP Solvent 1620, boiling point 166 to 202 ° C.)

[Aromatic solvent Y]
・TCP (tricresyl phosphate, boiling point 231-255°C)
・Dicyclohexyl phthalate (boiling point 222-228°C)

[Capsule preparation solvent]
- Ethyl acetate (boiling point 77°C)

[Photoactivator]
・ BMPS: Tribromomethylphenylsulfone (manufactured by Sumitomo Seika Co., Ltd.)
- B-IMD: lofein dimer (2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole (trade name "B-IMD", Manufactured by Kurogane Kasei))

[Color former]
・ LCV: Leuco Crystal Violet (trade name “LCV”, manufactured by Yamada Chemical Industry Co., Ltd.)
- Color former A: 3,3-bis (2-methyl-1-octyl-3-indolyl) phthalide (manufactured by BASF)

[Light stabilizer]
・ BTHQ: 2,5-bis (1,1,3,3-tetramethylbutyl) hydroquinone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[Capsule wall material]
D-110N: polyisocyanate (adduct of xylylene-1,3-diisocyanate and trimethylolpropane, trade name “Takenate D-110N”, manufactured by Mitsui Chemicals, 75% by mass ethyl acetate solution)
D-120N: polyisocyanate (an adduct of hydrogenated xylylene-1,3-diisocyanate and trimethylolpropane, trade name “Takenate D-120N”, manufactured by Mitsui Chemicals, Inc., 75% by mass ethyl acetate solution)

In addition, in the column of each component in Table 1, the numerical value in parentheses described together with the name of the component intends the content (parts by mass).
LCV corresponds to a coloring agent that develops color by oxidation, and exhibits blue color by oxidation. The coloring agent A corresponds to a coloring agent that develops color under the action of an acid, and exhibits a red color under the action of the acid.
Ethyl acetate, a solvent for preparing capsules used in Examples and Comparative Examples, did not remain in the microcapsules after preparation of the ultraviolet sensing member. In other words, the microcapsules in the ultraviolet sensing member of the present invention did not contain ethyl acetate.

[Measurement and evaluation]
[Sensitivity (wavelength 222 nm)]
Care 222 (registered trademark, manufactured by Ushio Corporation) was used to set the wavelength to 222 nm for the ultraviolet sensitive layer of the ultraviolet sensitive member produced in each example and comparative example, and the integrated illuminance was 1 mJ/cm ² or 3 mJ/cm ² . The distance and time were adjusted to irradiate the light.
Next, an image of the obtained sheet is read using an A4 scanner (GT-F740/GT-X830, manufactured by Epson Corporation), and the obtained image is analyzed by a UV light amount distribution analysis system (FUD-7010J, manufactured by Fujifilm Corporation). was used to analyze the density (DA1) of the colored portion formed in the ultraviolet sensitive layer and colored at each integrated illuminance. Then, the difference (DA1-DA0) between the density of the uncolored portion (DA0) and the density of the colored portion (DA1) was obtained and defined as the sensitivity (ΔDA). Sensitivity evaluation was performed based on the following evaluation criteria. When LCV was used as the color former, the OD-C value was used. .

<Evaluation Criteria>
"A": ΔDA is 0.1 or more at an integrated illuminance of 1 mJ/cm ² and ΔDA is 0.1 or more at an integrated illuminance of 3 mJ/cm ² .
"B": ΔDA is less than 0.1 at an integrated illuminance of 1 mJ/cm ² and ΔDA is 0.1 or more at an integrated illuminance of 3 mJ/cm ² , or ΔDA is at an integrated illuminance of 1 mJ/cm ² 0.1 or more, and ΔDA is less than 0.1 when the integrated illuminance is 3 mJ/cm ² .
"C": ΔDA is less than 0.1 at an integrated illuminance of 1 mJ/cm ² and less than 0.1 at an integrated illuminance of 3 mJ/cm ² .

From the results in Table 1, it was confirmed that the ultraviolet sensing member of the present invention has excellent sensitivity at a wavelength of 222 nm.
It was confirmed that the effects of the present invention are more excellent when the photoactive agent is a photoacid generator and the color former is a color former that develops color under the action of acid (comparison with Examples 1 and 2, etc.). .
When the capsule wall of the microcapsule contains one or more resins selected from the group consisting of polyurea, polyurethaneurea, and polyurethane having an alicyclic ring, it was confirmed that the effects of the present invention are more excellent (implementation (compare Examples 1 and 5).

10 UV Sensing Member 12 Support 14 UV Sensing Layer

Claims

An ultraviolet sensing member comprising an ultraviolet sensitive layer containing microcapsules encapsulating a photoactive agent, a coloring agent, and a solvent,
An ultraviolet sensing member that satisfies at least one of condition A and condition B.
Condition A: The solvent contains a non-aromatic solvent X having a heteroatom.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
The ultraviolet sensing member according to claim 1, wherein the solvent has a boiling point of 100°C or higher.
The non-aromatic solvent X contains one or more solvents selected from the group consisting of aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. 3. The ultraviolet sensing member according to 1 or 2.
The non-aromatic solvent Z is one or more solvents selected from the group consisting of aliphatic hydrocarbons, aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. The ultraviolet sensing member according to any one of claims 1 to 3, comprising
The ultraviolet sensing member according to any one of claims 1 to 4, wherein the aromatic solvent Y contains an aromatic solvent having a heteroatom.
the photoactive agent is a photooxidant;
The ultraviolet sensing member according to any one of claims 1 to 5, wherein the coloring agent is a coloring agent that develops color when oxidized.
the photoactive agent is a photoacid generator,
The ultraviolet sensing member according to any one of claims 1 to 5, wherein the coloring agent is a coloring agent that develops color under the action of an acid.
The ultraviolet sensing member according to any one of claims 1 to 7, wherein the photoactive agent contains a compound represented by general formula (6).
R 3 -L 1 -CX 3 X 4 X 5 (6)
In general formula (6), R 3 represents an optionally substituted aryl group or an optionally substituted heteroaryl group. L 1 represents -SO- or -SO 2 -. X 3 , X 4 and X 5 each independently represent a hydrogen atom or a halogen atom. However, the case where all of X 3 , X 4 and X 5 are hydrogen atoms is excluded.
The microcapsules do not contain an ultraviolet absorber having a benzotriazole structure, or
When the microcapsules contain an ultraviolet absorber having a benzotriazole structure, the content of the ultraviolet absorber having a benzotriazole structure is 1% by mass or less with respect to the total mass of the photoactive agent, claim 1 9. The ultraviolet sensing member according to any one of items 1 to 8.
The ultraviolet sensing member according to any one of claims 1 to 9, which senses ultraviolet rays with a wavelength of 200 to 230 nm.
A microcapsule encapsulating a photoactive agent, a color former, and a solvent,
A microcapsule that satisfies at least one of condition A and condition B.
Condition A: The solvent contains a non-aromatic solvent X having a heteroatom.
Condition B: the solvent contains an aromatic solvent Y and a non-aromatic solvent Z;
The microcapsules according to claim 11, wherein the solvent has a boiling point of 100°C or higher.
The non-aromatic solvent X contains one or more solvents selected from the group consisting of aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. 11. Microcapsules according to 11 or 12.
The non-aromatic solvent Z is one or more solvents selected from the group consisting of aliphatic hydrocarbons, aliphatic carboxylic acids, fatty acid esters, ether solvents, alcohol solvents, amide solvents, and ketone solvents. Microcapsules according to any one of claims 11 to 13, comprising
The microcapsules according to any one of claims 11 to 14, wherein the aromatic solvent Y contains an aromatic solvent having a heteroatom.
the photoactive agent is a photooxidant;
The microcapsules according to any one of claims 11 to 15, wherein the coloring agent is a coloring agent that develops color upon oxidation.
the photoactive agent is a photoacid generator,
The microcapsules according to any one of claims 11 to 15, wherein the coloring agent is a coloring agent that develops color under the action of an acid.
The microcapsule according to any one of claims 11 to 17, wherein the photoactive agent comprises a compound represented by general formula (6).
R 3 -L 1 -CX 3 X 4 X 5 (6)
In general formula (6), R 3 represents an optionally substituted aryl group or an optionally substituted heteroaryl group. L 1 represents -SO- or -SO 2 -. X 3 , X 4 and X 5 each independently represent a hydrogen atom or a halogen atom. However, the case where all of X 3 , X 4 and X 5 are hydrogen atoms is excluded.
A method for producing the microcapsules according to any one of claims 11 to 18,
mixing the color former, the photoactive agent, the solvent, and the emulsifier in water to prepare an emulsion;
forming a resin wall around the oil droplets containing the coloring agent, the photoactive agent and the solvent in the emulsified liquid obtained in the above step for encapsulation to form the microcapsules. , a method for producing microcapsules.
A dispersion for forming an ultraviolet sensitive layer, containing the microcapsules according to any one of claims 11 to 18.
An ultraviolet sensing kit comprising the ultraviolet sensing member according to any one of claims 1 to 10.