JPH0225370A - Recording material - Google Patents

Abstract

PURPOSE:To increase color development and fresh preservation capabilities as well as the stability of a color-developing image and thereby allowing a color developing section to absorb light from a near infrared region by adding a specific substance with molecules containing an oxazine ring substituted with an oil-soluble group and an electron-acceptive compound. CONSTITUTION:A fluorene derivative as a specific substance means di-substituted aminofluorene compound with oxazine in the ninth position, and the preferable type is such as expressed by the following formula: In the formula, R<1>, R<2>, R<3>, R<4>, R<5> and R<6> are alkyl groups, alkenyl groups, alkinyl groups, allyl groups and hydrogen atoms, and these may be the same or different. R<7> is an oil-soluble group. In addition, the substituted groups expressed by R<1>, R<2>, R<3>, R<4>, R<5> and R<6> may be substituted with alkyl groups, alkoxy groups, alkylthio groups, aryl groups, aryloxy groups, halogen atoms, nitro groups, cyano groups, substituted amino groups, substituted carbamoyl groups, substituted sulfamoyl groups, substituted oxycarbonyl groups or substituted oxysulfonyl group heterocyclic rings, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a recording material, and in particular, the present invention relates to a recording material having a coloring part absorbing light in the near-infrared region and improving coloring property, shelf life, and stability of a coloring formation. This invention relates to a recording material using an electron-donating colorless dye and an electron-accepting compound.

(Prior Art) Recording materials using an electron-donating colorless dye and an electron-accepting compound are already well known as pressure-sensitive paper, heat-sensitive paper, light-sensitive pressure-sensitive paper, electrically conductive heat-sensitive recording paper, and the like.

For example, British patent 2/1101111, US patent ≠≠
100!2, 11113t920. Tokuko Sho & 0-23
, ri2co, JP-A-37-/7ri, za3A, 60-1.
23,! ! A, same 1,0-/23,! ! I am familiar with 7 etc.

The properties that a recording material should have are (1) sufficient color density and color development sensitivity, (2) no capri, (3) sufficient fastness of the color body after color development, (
4) Appropriate color hue and suitability for copying machines (5) S
/N ratio should be high, and (6) the color former should have sufficient chemical resistance, but currently there is no product that completely satisfies these requirements.

In particular, heat-sensitive recording materials have the disadvantage that fogging occurs due to solvents and the like, and the color formers are subject to discoloration and discoloration due to exposure to oils, fats, chemicals, etc. Therefore, water-based ink, oil-based ink, fluorescent paint, ink, adhesive,
When it comes into contact with stationery and office supplies such as diazo liquid, or cosmetics such as hand cream and emulsion, the white part becomes colored or the colored part changes color and fades, significantly reducing the product value. The present inventors have investigated the oil solubility, water solubility, partition coefficient, pKa, polarity of substituents, position of substituents, crystallinity when mixed, and solubility for each of the electron-donating colorless dye electron-accepting compounds. We have pursued the development of good materials for recording materials and recording materials, focusing on characteristics such as changes in sex. Furthermore, in recent years, there has been a desire to develop recording materials that absorb in the near-infrared region.

Compounds with various skeletons have been proposed as electron-donating colorless dyes used in recording materials that absorb in the near-infrared region. /
-21114qj issue, same j/1tlt9j issue, same j/
-/, 2103! No., 721037, /, 21031
No., &0-230Zari No. 0, etc. are disclosed. However, none of these materials has been obtained that has absorption in the near-infrared region and completely satisfies the performance requirements (1) to (6).

Further, a fluorene oxazine type has been developed as an improved type of the fluorene phthalide type, but this type has drawbacks such as easy fogging of white parts.

(Object of the Invention) Therefore, the object of the present invention is to provide a recording material which has good color development properties, shelf life, and stability in both peaks of color development, and in which the color development portion absorbs light in the near-infrared region.

(Structure of the Invention) The object of the present invention has been achieved by a recording material characterized by containing a fluorene derivative having an oxazine ring substituted with an oil-soluble group in the molecule and an electron-accepting compound.

The fluorene derivative according to the present invention refers to a disubstituted aminofluorene compound having oxazine at the 3-position, and is preferably represented by the following general formula (1).

(In the formula, R1, R2, R3, R4, R5 and R6 represent an alkyl group, an alkenyl group, an alkynyl group, an aryl group, and a hydrogen atom, and these may be the same or different. 1. R7 represents an oil-soluble group. .) In the above formula, R1, R2, R
The substituents represented by 3, R4, R5 and R6 further include:
Alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, halogen atom, nitro group, cyan group, substituted amino group 1. It may be substituted with a substituted carbamoyl group, a substituted sulfamoyl group, a substituted oxycarbonyl group, a substituted oxysulfonyl group, a heterocycle, or the like.

These direct substituents may further have a substituent.

Specifically, R1, R2, R3, R4, R5 and R6 are H, -CH3, -CnH2n-1"zs-CnH2n-
3Yz% 'nH2n-3%CnCnH2n0C■
2m-IYZ, (n is an integer from λ to 10, m is an integer from / to Y, Y and Z are hydrogen atoms, halogen atoms, alkyl groups, aryl groups, alkoxy groups, nitro groups, cyan groups, and substituted amino groups etc.) R1 and R2, R3 and R4, or R5 and R6 may be bonded to each other to form a ring having a heteroatom or an unsaturated bond, in which case,
! (i represents an integer from t to 7, and Y represents the above-mentioned group) is a preferable example.

In the above general formula (I), the oil-soluble group represented by R is preferably an alkyl group having 2 to 30 carbon atoms. The alkyl group represented by R may be saturated or unsaturated, may form a ring, or may be branched. R is furthermore
rogen atom, alkyl group, aryl group, alkoxy group,
It may be substituted with an alkylthio group, an aryloxy group, a nitro group, a cyano group, or the like. As R7, carbon number J-
, 20 alkyl group, alkoxyalkyl group, carbon number 7
The aryl-substituted alkyl group and the allyloxyalkyl group of ~Cj are particularly preferred.

As shown, It is not limited to these.

It can be placed anywhere, but 2nd or 3rd place is preferable. That is, 3. t-disubstituted aminofluorene compound or
2. A-disubstituted aminofluorene compounds are preferred.

Next, we will discuss specific examples of fluorene derivatives according to the present invention. There are several methods for synthesizing these fluorene derivatives. .6-
After conversion to sil-substituted aminofluorene-terol, m
A fluorene derivative can be obtained by dehydration condensation with a -substituted aminoaniline derivative or the like and oxidation.

In this way, the intermediate, 3. Compounds (1) to (7) are derived from O-disubstituted aminofluorenone. Similarly, from co,z-disubstituted aminofluorenone, compound (8
)~I is derived.

These may be used alone, but may be used in combination for 2 seconds or more in order to adjust the hue and prevent fading of both peaks of color development.

These fluorene derivatives are compatible with other electron-donating colorless dyes,
For example, triphenylmethane phthalide compounds, fluoran compounds, phenothiazine compounds, indolyl phthalide compounds, leucoauramine compounds, rhodamine lactam compounds, to/4t triphenylmethane compounds, triazene compounds, spiropyran compounds. It is preferable that the compound be used in combination with various compounds such as fluorene compounds, etc., and that one type exhibiting a black color be used in combination.

Specific examples of phthalides are given in U.S. Patent Reissue No. λ3.0.
No. 211, U.S. Pat. No. 3. trill.

No. 777, same No. 3. ≠ri/, No. 112, same No. 3゜≠ri/
, No. 111 and No. 3. ! 0ri, /7μ issue, Tokukai Sho J
J-/7077, specific examples of fluorans are given in U.S. Pat.
No. 717, same No. 3. AIl, /, 0// issue, same No. 3. ≠
62. Zalr No. 3. tt/, No. 320, No. 3.
λθ, j70, same No. 3. the law of nature! U.S. Pat. No. 3.97/, Ij
'0za, pyridine and pyrazine compounds are U.S. Patent No. 3.77J-, 11211, U.S. Pat.
33°, No. ≠9.2≠t, 3/l', specific examples of fluorene compounds are JP-A No. 43-III/ZA-3, Japanese Patent Application No. 1986-1999-13, No. 9.2≠t, 3/l', It is described in No.lr etc.

As the electron-accepting compound according to the present invention, phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids, acid clay, bentonite, novolac resins, metal-treated novolac resins, metal complexes, etc. may be used. Examples of these are Tokuko Sho+0-ta 3゜ri issue, Tokko Akihiro 1-/≠032 issue,
JP-A Sho j2/gu Ogu g3, JP-A Sho≠J'-J/j10
No., JP-A No. 47-2101 #, JP-A No. 170-170
&'9 issue, JP-A-1983-//21 issue, JP-A-60-/
7t7ri No. 5, Tokukai Sho A/-ta yori ♂za No., Tokukai Sho A2
-3Aλ≠7, as described in Japanese Patent Application No. 6-≠7-23.

In the recording material according to the present invention, the electron-accepting compound is preferably used in an amount of too much weight percent of the electron-donating colorless dye, more preferably in an amount of 100 to 1000 percent by weight. Among the electron-accepting compounds, it is preferable that the salicylic acid derivative of the present invention is contained in an amount of IO weight % or more, and it is particularly preferable that the salicylic acid derivative of the present invention is contained in an amount of IO weight % or more.

These may be used alone or in combination. Among these, electron-accepting compounds consisting of salicylic acid derivatives and metal salts are preferred, and zinc salts are particularly preferred.

The recording material according to the present invention has a color-forming part that absorbs light in the near-infrared region, has sufficient color density, and is extremely stable in color patches, which hardly change even after long-term light irradiation, heating, and humidification. Since it does not cause discoloration, it is particularly advantageous in terms of long-term preservation of records. In addition, when used as a heat-sensitive recording material, there is no drawback that uncolored areas develop color due to solvents, etc., or the colored body discolors or fades due to oils, fats, chemicals, etc., so it has near-ideal performance as a recording material. .

When used in thermal paper, the electron-donating colorless dye and the electron-accepting compound have a particle size of 10 μm or less, preferably 3 μm or less, in the dispersion medium.
It is used after being crushed and dispersed to a particle size of μ or less. As a dispersion medium, a water-soluble polymer aqueous solution with a concentration of about 0.3 to 10% is generally used, and dispersion is carried out using a ball mill, sand mill, or
This is done using a horizontal sand domino pair writer, colloid mill, etc.

The ratio of the electron-donating colorless dye to the electron-accepting metal compound used is preferably between /:10 and /:/, and more preferably /:! A ratio between 2:3 and 2:3 is particularly preferred. Further, a thermofusible substance can be contained in the thermosensitive coloring layer in order to improve its thermal responsiveness.

Examples of thermofusible substances include JP-A-1-372r, JP-A-170!74t, and JP-A-6/-1,23Jl.
r/etc.

These may be used alone or in combination, and in order to obtain sufficient thermal responsiveness, the electron-accepting compound should have a ratio of /0-. It is preferable to use 200% by weight,
A more preferable usage amount is 20 to /jO% by weight.

Additives are further added to the coating liquid obtained by mixing the thus obtained dispersion in an appropriate ratio to meet various requirements.

Examples of additives include dispersing oil-absorbing substances such as inorganic pigments and polyurea fillers in the binder in order to prevent the recording head from becoming dirty during recording, and also to improve the releasability of the head. l- Fatty acids, metal stones, etc. are added to increase the strength. Therefore, in addition to colorless dyes and electron-accepting compounds that contribute to color development, pigments, waxes, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, fluorescent dyes, surfactants, hindered phenol benzoic acid, etc. Additives such as derivatives are applied onto the support to constitute the recording material.

Specifically, pigments such as kaolin, calcined kaolin, talc, zinc white, aluminum hydroxide, magnesium hydroxide, calcined surface wax, silica, magnesium carbonate, titanium oxide, alumina, barium carbonate, barium sulfate, mica,
Microballoon, urea-formalin filler, polyethylene chime tickle, cellulose filler, etc. particle size 0.
Selected from /naishi/jμ. Examples of waxes include chisel rough fin wax, carboxy-modified paraffin wax, carnauba wax, microcrystalline wax, polyethylene wax, and higher fatty acid esters. When using an inorganic pigment, the amount of inorganic pigment used is 0.3-20% of the electron accepting compound.
A ratio of 7 to 70 times (weight ratio) is preferable, and a ratio of 7 to 70 times is particularly preferable.

Examples of metal stones include polyvalent metal salts of higher fatty acids, such as zinc stearate, aluminum stearate, calcium stearate, and zinc oleate.

The hindered phenol is at least λ or 6
Phenol derivatives in which seven or more of the positions are substituted with branched alkyl groups are preferred.

For example, /, /-bis(2-methyl-t-hydroxy-j-t-butylphenyl)methane, /.

/,3-)IJsu(3-methyl-μmhydroxy!-t
-butylphenyl)methane, bis(2-hydroxy-3
-t-tsuchiru! -methylphenyl)methane, bis(2
-Methyl-gu-hydroxy-! L-butylphenyl) sulfide s.

These are dispersed and applied in a binder.

As the benzoic acid derivative, a metal salt of benzoic acid having / or more electron-withdrawing groups is preferable, and specifically, halogen-substituted benzoic acid, nitrobenzoic acid, cyanobenzoic acid, substituted sulfonylbenzoic acid, acylbenzoic acid, substituted Examples include zinc salts, aluminum salts, cadmium salts, magnesium salts, calcium salts, etc. of carbamoylbenzoic acid, alkoxycarbonylbenzoic acid, substituted sulfamoylbenzoic acid, and the like. Particularly preferred are zinc salts. These can also be used as electron-accepting compounds. These are mixed with an electron-accepting compound or dispersed alone and applied.

Water-soluble binders are generally used, such as polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, epichlorohydrin-modified polyamide, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, isoduchylene-maleic anhydride. Acid copolymers, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives,
Examples include casein and gelatin. In addition, water-resisting agents (gelling agents,
A crosslinking agent) or a hydrophobic polymer emulsion, specifically, styrene-butane, 2 l-diene rubber latex, acrylic resin emulsion, etc. can also be added. Coating can be done on base paper, high quality paper, synthetic paper,
λ~/Og on a plastic sheet or neutral paper
/m2 is applied.

Further, the coated surface layer is coated with O6.2~, which is composed of a water-soluble or water-dispersible polymer compound such as polyvinyl alcohol, hydroxyethyl starch, or epoxy-modified polyacrylamide, and a crosslinking agent. It is also possible to provide a protective layer with a thickness of about 2μ to improve resistance.

When used for thermal paper, OLS, 2221jr/
Issue, same, 2/10 za tag, Tokko Akira! λ-λθ/'72, etc. may be used. Alternatively, operations such as preheating, humidity control, or stretching of coated paper may be added prior to recording.

(Examples of the Invention) Examples will be shown below, but the present invention is not limited only to these examples.

Synthesis Example 3, t-bisdiethylaminofluorentaol3.
24Lg and m-diethylaminophenyl, 2.2 acetanilide λ, J', 2g, methanol 11ml,
It was dissolved in 7 ml of water and 2 ml of concentrated hydrochloric acid, and heated under reflux for 7 hours. After pouring the reaction mixture into 200 ml of ice water, 200 ml of diluted caustic soda water was added to make it alkaline. This was extracted with ethyl acetate, 200ml,
The organic layer was washed with water, dried, and concentrated to obtain a dehydrated condensation crude product. This crude product was mixed with 10 ml of methanol.
Dissolve in 1 liter and 10 ml of acetic acid, heat to some extent, and place Floranil! ,≠jg were added thereto, and the mixture was heated under reflux for 2 hours.

The reaction mixture was poured into 3 ooml of ice water, 200 ml of diluted caustic soda water was added thereto, and the mixture was stirred. When the resulting precipitate was separated and recrystallized from ethyl acetate-hexane, the compound (
3) to 3. ll! I got g.

(M/e=jr&, mp, /J Turf Hiro 00C) When compound (3) was brought into contact with bisphenol A, it gave a bright green color.
It had a spectral absorption peak at m.

Example/ Compound (1) rg, λ-anilino-3-chloro-2-diethylaminofluorane f, which is an electron-donating colorless dye
g and 3/, tl-bisdiethylamino-j-diethylaminospiro(isobenzofuran-/,ri'-fluorene)-3-one 2g % is an electron-accepting compound≠-
Zinc β-p-methoxyphenoxyethoxysalicylate 2
0 g, thermofusible substances, 10 g of λ-benzyloxynaphthalene and 10 g of stearic acid amide/jg each.
0g! Chipolyvinyl alcohol (Kuraray PVA10j
) The particles were dispersed together with an aqueous solution in a liquid volume mill for one day to give a volume average particle size of 3 μm. On the other hand, 10 g of a mixture of calcium carbonate and zinc oxide was added to 0.0 g of sodium hexametaphosphate. j
% solution/AOg using a homogenizer.

Disperse each dispersion as described above to create an electron-donating colorless dye dispersion! g1 10 g of electron-accepting compound dispersion, thermofusible substance dispersion sg, calcium carbonate and zinc oxide dispersion 22
A coating liquid was obtained by mixing 47 g of zinc stearate emulsion and 2% aqueous solution tg of sodium (,2-ethylhexyl)sulfosuccinate. This coating liquid was dried on a high-quality paper weighing r Og/m2, applied with a wire spar so that the coating amount was &g/m2, dried in an oven at RO 0C for 5 minutes, and calendered to obtain coated paper. Ta.

When the color was developed using Fujitsu High Speed Facsimile FF-2ooo, a black impression was obtained. This colored part had light absorption in the near-infrared region. Furthermore, when F paper was impregnated with ethanol and castor oil and superimposed on the colored surface of the recording paper obtained by the above method, fogging in the white area and decoloration (discoloration) in the colored area were hardly observed. There wasn't.

On the other hand, the obtained coated paper was heated to a high temperature (Ao0C130%RH).
Although it was stored for 2 q hours under conditions of high humidity and high humidity (Hiroo'C, RiOchiRH), almost no fogging occurred.

Examples λ to G In place of the electron-donating colorless dye and electron-accepting compound in Example 1, the following were used, respectively. Others were -, 2j Coated paper was obtained in the same manner as in Example.

Example λ Electron-donating colorless dye: Compound (3) J'gs'anilino-3-methyl-t-N-ethyl-N-isoamylaminofluoran Igz and 3',6'bisdiethylamino-j-diethylaminospiro ( Isobenzofuran-/,
ri'-fluorene) 3-one/g Electron-accepting compound: /, Hiro-bis(p-hydroxycumyl)benzene 10g, bis(+2-hydroxy-j
-biphenyl) sulfone zinc salt 1 g and rhodan zinc benzimidazole complex + g Example 3 Electron-donating colorless dye Compound (t) iog, x Anilino-3-methyl-J -N-ethyl-N isoamylaminofluorane 10 g Electron Accepting compound /, /bis(+-hydroxyphenyl)cyclohexane lrg ag Example≠ Electron-donating colorless dye: Compound (r)iogs λanilino-3-chloro-6-dinithylaminofluorane 10g Electron-accepting compound: Molybdic acid acetylacetone complex 10g5 and bisphenol sulfone 10g Colored images are close to each other It had light absorption in the infrared region, and there was also little glare.

Patent applicant: Fuji Photo Film Co., Ltd., 271

Claims (1)

[Claims] A recording material comprising a fluorene derivative having an oxazine ring substituted with an oil-soluble group in its molecule and an electron-accepting compound.