JPH04320883A - Color forming recording material - Google Patents

Abstract

PURPOSE:To obtain a dye having strong absorption intensity within a region from a visible light region to a near infrared region and fastness by adding a quinonediimine derivative represented by a specific general formula and an acidic substance. CONSTITUTION:A color forming material is obtained by adding two components of a quinonediimine derivative represented by formula I [wherein A and B are respectively independently an aryl group or the like, R<1>, R<2>, R<3> and R<4> are the same or different and are a hydrogen or the like or R<1> and R<2> or R<3> and R<4> can be mutually bonded to form a group representea by formula II (wherein R<5>, R<6> R<7> and R<8> are the same or different and are a hydrogen atom or the like)] and an acidic substance. As the acidic substance, both of an org. compound and an inorg. compound can be used. By bringing these two components to a contact state, a dye having strong absorption intensity within a region from a visible light region to a near infrared region and fastness can be obtained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to color-forming recording materials. More specifically, the present invention relates to a color-forming recording material that exhibits absorption in visible light to near infrared rays and is thus useful for reading information with equipment.

0002

2. Description of the Related Art Hitherto, color-forming recording materials made of dyes that are colorless per se and acidic substances have been widely put into practical use as heat-sensitive recording materials.

However, in recent years, with the development of electronic technology and information management systems, record reading devices that are sensitive to electromagnetic waves in the long wavelength range from the long wavelength range of visible light to the near infrared range have come into practical use. However, conventionally commonly used color-forming recording materials using phthalide compounds as color-forming dyes do not have practical absorption in such long wavelength regions.

That is, in order to shift the absorption wavelength of conventionally known phthalide compounds to the near-infrared region, it is necessary not only to utilize the substituent effect on the compound but also to extend the π-electron conjugated system. However, this method increases the molecular weight of the compound, making it difficult to manufacture, and the absorption in the near-infrared region is still insufficient. Also,
Colored images are unstable, easily fade, and have poor light fastness.

Therefore, in recent years, various color-forming dyes that form pigments that absorb electromagnetic waves in the long wavelength range have been proposed. JP-A-62-142681 and JP-A-62-18
No. 1361 proposes a color-forming recording material containing two elements: a phenylene diamine derivative or a naphthylene diamine derivative and an acidic substance.

However, according to experiments conducted by the present inventors, a follow-up test of the embodiment described in the above publication revealed that
It was difficult to achieve sufficient color development in the near-infrared region and readout at 780 nm. Furthermore, Unexamined Japanese Patent Publication No. 6
No. 3-256486 proposes a color-forming recording material containing two elements: a phenylenediamine derivative or a naphthylenediamine derivative, and a quinoid electron-accepting compound as an oxidizing agent. However, according to experiments conducted by the present inventors, in a recording paper containing a phenylenediamine derivative or a naphthylenediamine derivative and a quinoid-type electron-accepting compound, which was prepared by replicating the example described in the same publication, In some cases, even when heated, sufficient color development could not be achieved.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a color-forming recording material. Another object of the present invention is to provide a color-forming recording material that produces a color of sufficient intensity for practical use immediately after a color-forming operation and that has absorption in the long wavelength range from the visible light region to the near-infrared region. .

[0008]

According to the present invention, the above objects and advantages of the present invention are achieved by: (a) General formula (I)

[0009]

[Chemical 2]

This is achieved by a color-forming recording material characterized by containing a quinodiimine derivative represented by the following formula and (b) an acidic substance.

The color-forming recording material according to the present invention has the above (a)
) and (b). By bringing these two components into contact, it is possible to obtain a dye that has extremely strong absorption strength and fastness in the visible light region to near-infrared region. Therefore, the present invention provides a practical color-forming recording material that is sensitive to semiconductor lasers.

The quinone diimine derivative (a) used in the present invention is represented by the above general formula (I).

In formula (I), A and B each independently represent an aryl group, an alkyl group or an aralkyl group. The aryl group moiety of the aryl group and aralkyl group includes a halogen atom, a cyano group, a hydroxyl group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an aralkyloxy group, an alkylcarbonyloxy group, an arylcarbonyloxy group, an amino group, and an alkyl group. It may have at least one substituent selected from the group consisting of a substituted amino group, an aryl-substituted amino group, an acylamino group, a pyrrolidino group, a piperidino group, and a carbamoyl group.

[0014] Furthermore, in formula (I), R1, R2, R
3 and R4 are the same or different and are a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a hydroxyl group, or a halogen atom, or R1 and R2 or R
3 and R4 can be bonded to each other to represent a group represented by the following formula -CR5=CR6-CR7=CR8-. R5, R6, R
7 and R8 are the same or different and are a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a hydroxyl group, or a halogen atom.

When R1, R2, R3 and R4 are all hydrogen atoms, alkyl groups, aryl groups, aralkyl groups, hydroxyl groups or halogen atoms, the compound of formula (I) is a quinone diimine. R1 and R2 or R
Either one of 3 and R4 is a group -CR5=CR6-C
When R7=CR8-, the compounds of formula (I) are naphthoquinone diimines. Also, R1, R2 and R
Both sets of 3 and R4 are groups -CR5=CR6-CR7
When =CR8-, the compounds of formula (I) are anthraquinone diimines.

Examples of the quinonediimine derivative (a) of formula (I) include N,N'-diphenyl-p-quinonediimine, N-(4-hydroxyphenyl)-N'-phenyl-p-quinonediimine, N-( 4-methoxyphenyl)-N'-phenyl-p-quinonediimine, N-(4
-ethoxyphenyl)-N'-phenyl-p-quinonediimine, N-(3-hydroxyphenyl)-N'-phenyl-p-quinonediimine, N-(3-methoxyphenyl)-N'-phenyl-p-quinonediimine, N-(4
-t-butylcarbonyloxyphenyl)-N'-phenyl-p-quinonediimine, N-(4-aminophenyl)-N'-phenyl-p-quinonediimine, N-(4-
alininophenyl)-N'-phenyl-p-quinonediimine, N-(4-(3-methoxyphenylamino)phenyl-N'-phenyl-p-quinonediimine, N-(1
-Methyl-4-hydroxyphenyl)-N'-phenyl-p-quinonediimine, N-(2-methyl-4-methoxyphenyl)-N'-phenyl-p-quinonediimine,
N-(2,3-dimethyl-4-hydroxyphenyl)-
N'-phenyl-p-quinonediimine, N-(4-t-
butylcarboxyphenyl)-N'-ethyl-N'-phenyl-p-quinonediimine, N-(4-fluorophenyl)-N'-phenyl-p-quinonediimine, N-(
4-chlorophenyl)-N'-phenyl-p-quinonediimine, N-(4-bromophenyl)-N'-phenyl-p-quinonediimine, N-(4-nitrophenyl)-
N'-phenyl-p-quinone diimine, N,N'-diphenyl-1,4-naphthoquinone diimine, N,N'-diphenyl-1,4-anthraquinone diimine, N,N'
-diphenyl-2,3,5,6-tetrachloro-p-benzoquinone diimine, N,N'-diphenyl-2,3-
Dichloro-p-benzoquinone, N,N'-diphenyl-
2,5-dichloro-p-benzoquinone, N,N'-diphenyl-2,5-dichloro-5,6-dicyano-p-benzoquinone, N,N'-diphenyl-2-chloro-p-
Benzoquinone, N,N'-diphenyl-2-methyl-p
-benzoquinone, N,N'-diphenyl-2-ethyl-
p-benzoquinone, N,N'-diphenyl-2,3-dimethyl-p-benzoquinone, N,N'-diphenyl-2
, 5-dimethyl-p-benzoquinone, N,N'-diphenyl-2,3-diethyl-p-benzoquinone, N,N'
-diphenyl-2,5-diethyl-p-benzoquinone,
2,N,N'-triphenyl-p-benzoquinone, 2,
5,N,N'-tetraphenyl-p-benzoquinone, N
, N'-diphenyl-2-benzyl-p-benzoquinone, N,N'-diphenyl-2,3-benzyl-p-benzoquinone, N,N'-diphenyl-2,5-benzyl-
p-benzoquinone, N,N'-diphenyl-2-hydroxy-p-benzoquinone, N,N'-diphenyl-2,
Examples include 5-dihydroxy-p-benzoquinone.

In the present invention, both organic compounds and inorganic compounds can be used as the acidic substance (b). Examples of organic compounds include aromatic carboxylic acids such as benzoic acid and naphthoic acid, aromatic hydroxycarboxylic acids such as hydroxybenzoic acid and hydroquinaphthoic acid, p
Preferred examples include organic sulfonic acids such as -toluenesulfonic acid and acidic resins such as phenol resins.

Preferred examples of inorganic compounds include activated clay, kaolin, and clay.

As the acidic substance (b), the above compounds can be used alone or in combination of two or more.

[0020] Furthermore, the color-developing recording material in the present invention is
It may also contain an oxidizing agent. The oxidizing agent used may be either organic or inorganic. Examples of organic oxidizing agents include quinoid electron-accepting compounds, organic halogen compounds, phosphine oxides, sulfoxides, disulfides, N-oxides, radical compounds, and other organic oxides. Agents include oxygen, halogen, metal oxides, halides,
Suitable examples include organic acid metal salts.

[0021] As is well known, conventional heat-sensitive recording materials are prepared by preparing an aqueous dispersion containing a coloring dye, a color developer such as bisphenol A, and other additives as necessary, as well as a binder. It is prepared by coating it on a substrate such as paper and drying it. When the color-forming recording material according to the present invention is used as a heat-sensitive recording material, an aqueous dispersion containing the quinone diimine derivative, an oxidizing agent, an acidic substance, and other additives used as necessary and a binder is prepared in the same manner as described above. It is prepared by coating it on a substrate such as paper and drying it.

As the binder, those conventionally used in the preparation of heat-sensitive recording materials can be suitably used. Preferred examples of such binders include polyvinyl alcohol, hydroxyethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic ester, polymethacrylic acid, polymethacrylic ester, etc. can be mentioned.

In the color-forming recording material of the present invention, the quinone diimine derivative (a) and the acidic substance (b), ie, the color developer, have a quinone diimine derivative/acidic substance molar ratio of preferably 0.01 to 100, more preferably 0. .05~2
Used in the range 0.

The color-forming recording material of the present invention may further contain a fluorescent dye or pigment. As a fluorescent dye,
For example, diaminostilbene type, benzimidazole type, benzidine type, imidazolone type, etc. can be mentioned. Examples of pigments include titanium dioxide, clay, talc, calcium carbonate, aluminum hydroxide, silica, and polystyrene resin.

Furthermore, the color-forming recording material of the present invention can also contain a sensitizer. Examples of the sensitizer include higher fatty acid amides such as stearamide, benzamide, stearanilide, cisetoacetanilide, thioacetanilide, dimethyl phthalate, dibenzyl oxalate, dibenzyl terephthalate, dibenzyl isophthalate,
Examples include 4,4'-dimethoxyphenyl sulfone. The recording material of the invention may also contain or be overcoated with an anti-blocking agent such as stearic acid, calcium stearate, zinc stearate, calcarnauba wax, paraffin wax and the like.

Pressure-sensitive recording paper is produced by using a conventional method, for example, by coating a top sheet paper with microcapsules containing a color-forming dye solution coated on its lower surface and carrying a color developer on its upper surface. Alternatively, the microcapsules and the color developer may be coated on the same paper surface.

[0027]

[Examples] The present invention will be explained below with reference to Examples.
The present invention is not limited in any way by these Examples.

Example 1 0.10 g of N,N'-diphenyl-p-quinone diimine
, 1-hydroxy-2-naphthoic acid 0.2178g, stearamide 0.10g, zinc stearate 0.1
0g, 10% polyvinyl alcohol aqueous solution 0.75g,
and 1.75 g of water in a planetary fine pulverizer (FRITSCH).
Co., Ltd.) for 10 minutes to obtain a coating solution.

Next, the obtained liquid was applied to high-quality paper using a bar coater (Tester Sangyo, P11210).
After air-drying, use a thermal paper color test device (T manufactured by Okura Electric Co., Ltd.).
H-PMD) to develop color by heating. The reflectance before and after coloring was measured using a UV measuring device (Shimadzu Corporation UV-3101)
) at 300 to 1300 nm.

FIG. 1 shows absorption curves before and after color development.

[0031] Also, NEC printer (PC-PR1
A barcode was printed using a thermal head (02TL). This barcode is printed using a semiconductor laser (780nm).
) Barcode reader (Symbol Technology
ogies Inc. , LS8200) and an LED barcode reader (Meccano Systems, M10).

[0032]

Effects of the Invention The color-forming recording material of the present invention contains a quinone diimine derivative and an acidic substance, gives a practically sufficient color development after a color-forming operation, and also absorbs in the long wavelength region from the visible light region to the near-infrared region. This makes it useful for reading information by devices.

[Brief explanation of the drawing]

FIG. 1 shows absorption curves before and after color development for the color-forming recording material of Example 1.

Claims (1)

[Claims] Claim 1: (a) a quinone diimine derivative represented by the general formula (I): and (b)
A color-forming recording material characterized by containing an acidic substance.