JPH02175185A - Additive for heat sensitive recording material - Google Patents

Abstract

PURPOSE:To improve recording sensitivity without reducing whiteness by adding specific hydantoin compound. CONSTITUTION:When hydantoin derivative represented by a formula 1 is added as an additive used in a heat sensitive recording layer of a heat sensitive recording material utilizing reaction of basic dye with developer, the mutual solubility of a whole mixture is enhanced at the time of heating and melting to provide a sensitizing effect of improving the sensitivity of developing reaction of the basic dye with the developer, thereby improving the high speed recording properties of the heat sensitive recording material without reducing its whiteness. In the formula 1, R is alkyl group, vinyl group or aryl group.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an additive for heat-sensitive recording materials, and more specifically, a colorless or light-colored basic dye, and a color developer that develops a color when it comes into contact with the dye. The present invention relates to an additive used in a heat-sensitive recording layer of a heat-sensitive recording material that utilizes a reaction with an additive.

[Prior Art] A heat-sensitive recording layer containing a basic dye and a color developer that reacts with the dye to develop color when heated is provided on a sheet-like base material (paper, polyester sheet, etc.), Thermosensitive recording materials with surface protective layers formed thereon are widely used in thermosensitive recording devices such as facsimiles, automatic ticket vending machines, and various printers.

In recent years, as heat-sensitive recording devices have been improved, diversified, and improved in performance, quality requirements for highly sensitive heat-sensitive recording materials capable of high-speed recording have become increasingly strict.

In order to improve the sensitivity of heat-sensitive recording materials, many proposals have been made to use thermofusible substances (fatty acid amides, fats and oils, etc.) as additives. However, as the recording sensitivity improves, new drawbacks such as a decrease in the stability of the heat-sensitive recording layer and, more specifically, a decrease in whiteness, accompany it, so the reality is that a satisfactory thermosensitive recording material is not always obtained. be.

[Problems to be Solved by the Invention] An object of the present invention is to provide an additive for use in a heat-sensitive recording layer of a heat-sensitive recording material that utilizes the reaction between a basic dye and a color developer.

Another object of the present invention is to provide an additive having a sensitizing effect that improves the sensitivity of the color developing reaction between a basic dye and an i-color agent when heated and melted.

Still another object of the present invention is to provide an additive for a heat-sensitive recording material that improves the high-speed recording properties of the heat-sensitive recording material without causing a decrease in whiteness.

[Means for Solving the Problems] The present inventors have conducted intensive research on a wide range of compounds in order to find suitable additives that can be used for heat-sensitive recording materials. We have discovered that there is a substance that improves recording sensitivity and does not cause a decrease in whiteness, and have completed the present invention.

That is, the present invention is an additive for heat-sensitive recording materials comprising a hydantoin derivative represented by the following general formula [I] (wherein R represents an alkyl group, a vinyl group, or an aryl group).

Although the details of the reason why the hydantoin compound of the present invention improves recording sensitivity without reducing whiteness are not clear, the compound represented by the general formula [I] One factor is considered to be to increase compatibility.

[Manufacturing method] The hydantoin nM conductor represented by the general formula [I] can be manufactured by a known method, for example, Encycl, CI+em.

Tech,, 3rd Ed, Vol, 12.695
It can be synthesized by the method described on the page.

That is, a hydantoin represented by the formula [ff] and a halogen compound represented by the formula [1111% formula %] (wherein, X represents a halogen atom and R represents the same meaning as above) are reacted in an alkaline solution. It can be synthesized with good yield by doing this.

Additive J The hydantoin compounds of the additive for heat-sensitive recording materials thus obtained include, for example, 3-(2-vinyloxyethyl)-hydantoin, 3-(2-ethyloxyethyl)-hydantoin, 3-(2-phenyl (oxyethyl)-hydantoin and the like.

Two or more types of hydantoin compounds as additives may be used in combination, and examples thereof include stearic acid amide, stearic acid methylene amide, oleic acid amide, palmitic acid amide, coconut fatty acid amide, etc. within a range that does not impede the effects of the present invention. fatty acid amide, 2,2'-methylenebis(4
-Methyl-61-butylphenol), 4,4'-butylidenebis(6-t-butyl-3-methylphenol), 1.1',3-tris(2-methyl-4-hydroxy-5-t-butylphenol) Hindered phenols such as butane, ultraviolet absorbers such as 2-(2'-hydroxy-5'-methylphenyl)-benzo(-lyazole, 2-hydroxy-4-benzyloxybenzophenone, etc.), and various known thermofusible It is also possible to use sexual substances together.

The amount of the additive having the above-mentioned specific structure used according to the present invention is not necessarily limited, but is generally 0.1 to 10 parts by weight, preferably 1.0 to 5 parts by weight, per 1 part by weight of the color developer. It is used in a range of about .0 parts by weight.

[Thermosensitive Recording Material 1 Next, a heat-sensitive recording material using the additive according to the present invention will be explained.

Examples of the colorless or light-colored basic dyes constituting the recording layer of the heat-sensitive recording material include the following.

3.3-his(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3.3-bis(p-dimethylaminophenyl)phthalide, 3-(p-dimethylaminophenyl) to 3-(1,2 −
Dimethylindol-3-yl)phthalide, 3-(p-dimethylaminophenyl)-3-(2-methylindol-3-yl)phthalide, 3.3-bis(1
, 2-dimethylindol-3-yl)-5-dimethylaminophthalide, 3.3-bis(1,2-dimethylindol-3-yl)-6-dimethylaminophthalide, 3
．． 3-bis(9-ethylcarbazol-3-yl)-6
-dimethylaminophthalide, 3.3-bis(2-phenylindol-3-yl)-6-dimethylaminophthalide, 3-p-dimethylaminophenyl-3-(1-methylvirol-3-yl)-6 - triarylmethane dyes such as dimethylaminophthalide, 4.4'-bis-dimethylaminobenzhydrylbenzyl ether, N-he〇phenyl=Oicoolamine, N-2,4,5
- Diphenylmethane dyes such as trichlorophenyl leuco auramine, thiazine dyes such as benzoyl leucomethylene blue p-nitrobenzoyl leucomethylene blue, 3-methyl-spiro-dinaphthopyran, 3-■ tyrus-spiro-dinaphthopyran, 3-phenyl-spiro- dinaphthopyran, 3-benzyl-spiro-dinaphthopyran, 3
Spiro-based dyes such as -methyl-naphtho(6'-methoxybenzo)spiropyran, 3,3'-cyclolosespirodinaphthopyran, 3-propyl-spiro-dibenzopyran, rhodamine-B-anilinolactam, rhodamine (p -nitroanilino)lactam, rhodamine (0-chloroanilino)lactam, rhodamine B (p
Lactam dyes such as -chloroanilino)lactam, 3-dimethylamino-7-methoxyfluoran, 3-diethylamino-6-methoxyfluoran, 3-diethylamine-7-methoxyfluoran, 3-diethylamino-7-chlorofluoran , 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-6,7-dimethylnorophane, 3-(N-ethyl-p-toluidino)-7-methylfluorane, 3-diethylamino -7-N-acetyl-N-methylaminofluorane, 3-diethylamino-7-N-methylaminofluorane, 3-diethylamino-7-dibenzylaminofluorane, 3-diethylamino-7-N-methyl-N~ Benzylaminofluorane, 3-diethylamino-7-N-chloroethyl-N-methylaminofluorane, 3-diethylamino-7-N-diethylaminofluorane, 3-(N-ethyl-p-toluidino)-6-methyl- 7
-phenylaminofluorane, 3-(N-ethyl-p-
toluidino)-6-methyl-7-(p-toluidino)fluorane, 3-diethylamino-6-methyl-7-phenylaminofluorane, 3-dibutylamino-6-methyl-7-phenylaminofluorane, 3-diethylamino -7-(2-carbomethoxy-phenylamino)fluorane, 3-(N-cyclohexyl-N-methylamine)6-
Methyl-7-phenylaminofluorane, 3-pyrrolidino-6-methyl-7-phenylaminofluorane, 3-piperidino-6-methyl-7-phenylaminofluorane, 3-diethylamino-6-methyl-7-xyly Dinofluorane, 3-diethylamino-7-(0-chlorophenylamino)fluoran, 3-dibutylamino-7-(0-chlorophenylamino)fluoran, 3-pyrrolidino-6-methyl-7-F)-butylphenylaminofluoran Orane, 3-(N-methyl-N-n-amyl)amino-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-N-n-amyl)amino-6-methyl-7-phenyl Aminofluorane, 3-(N-ethyl-N-iso-amyl)amino6-methyl-7-phenylaminofluorane, 3-(N-methyl-Nn-hexyl)amine-6
-Methyl-7-phenylaminofluorane, 3-(N-
Ethyl-Nn-hexyl)amino-6-methyl-7-
Phenylaminofluorane, 3-(N-ethyl-N-β
-ethylhexyl)amino-6-methyl-7-phenylaminofluorane, 3-(N-methyl-N-tetrahydrofurfurylamino)-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-N -tetrahydrofurfurylamino)-6-methyl-7-7enylaminofluorane, 2,2-bis[4-[6'-(N-cyclohexyl-
N-methylamino)-3'-methylspiro[phthalide-
3,9'-xanthine]-2'-ylaminocophenyl 1-propane, 2,2-bis[4-[6'-(N-cyclohexyl-
N-methylamino)-3'-methylspiro(phthalide-
Examples include 3,9'-xanthine)-2'-ylamino]phenyl]butane.

The color developer used in combination with the above basic dye is not particularly limited, and should have the property of liquefying, vaporizing, or dissolving when the temperature rises, and that does not come into contact with the above basic dye. Various color developers are used that have the property of causing color development. Typical specific examples include 4-tert-butylphenol, α-naphthol, β-naphthol, 4-acetylphenol, 4-tert-octylphenol, 4.4'-5e
c-butylidene diphenol, 4-phenylphenol, 4.4'-dihydroxy-diphenylmethane, 2.2-
Bis(4-hydroxyphenyl)propane, 4-hydroxyacetophenol, 4-tert-octylcatechol, 2,2'-dihydroxydiphenol, 2°,2'-methylenebis(4
-Methyl-6tert-isobutylphenol), 4.4'-isopropylidenebis(2-tert-butylphenol), 2.2'-methylenebis(4-chlorophenol), 2.2-bis(3-methyl-4- hydroxy)propane, 1.1-bis(4-hydroxyphenyl)ethane, 2.2-bis(4-hydroxyphenyl)-4-methylpentane, 4.4'-benzylidenebisphenol, hydroquinone, 4.4'-cyclo Hexylidene diphenol, 4.4'
-dihydroxydiphenyl sulfide, 4.4'-thiobis(6-tert-butyl-3-methylphenol), 3.4-dihydrooxydiphenyl-p-tolylsulfone, 4-hydroxy-4'-dioxydiphenylsulfone , 4-hydroxy-4'-isopropoxyphenyl sulfone, bis(3-allyl-4-human xyphenyl)-sulfone, 3-chloro-4-hydroxydiphenyl sulfone, 4.4'-dihydroxydiphenyl sulfone, hydroquinone mono Benzyl ether, 4-hydroxybenzophenone, 2.4-dihydroxybenzophenone, 2.4.4'
-trihydroxybenzophenone, 2.2', 4.4
-tetrahydroxybenzophenone, dimethyl 4-human 0-xyphthalate, methyl 4-human mixybenzoate, ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, 5ec-butyl 4-hydroxybenzoate, 4-hydroxybenzoic acid pendel, phenyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, tolyl 4-hydroxybenzoate, chlorophenyl 4-hydroxybenzoate, phenylpropyl 4-hydroxybenzoate, phenethyl 4-hydroxybenzoate, 4-hydroxybenzoic acid Phenolic compounds such as p-chlorobenzyl, p-methoxybenzyl 4-hydroxybenzoate, pentamethylenebis-4-hydroxybenzoic acid, propyl gallate, lauryl gallate, stearyl gallate, benzoic acid, p-tert -butylbenzoic acid, trichlorobenzoic acid, terephthalic acid, 3-5ec-butyl-4-hydroxybenzoic acid, 3-cyclohexyl-4-hydroxybenzoic acid, 3.5-dimethyl-4-hydroxybenzoic acid, salicylic acid, 3-isopropylsalicylic acid, 3-tert-butylsalicylic acid, 3-benzylsalicylic acid, 3-(α-methylbenzyl)salicylic acid, 3-chloro-
Aromas such as 5-(α-methylbenzyl)salicylic acid, 3.5-di-tert-butylsalicylic acid, 3-phenyl-5-(α,α-dimethylbenzyl)salicylic acid, 3.5-di-α-methylbenzylsalicylic acid, etc. group carboxylic acids, and these phenolic compounds, aromatic carboxylic acids,
Examples include organic acidic substances such as salts with polyvalent metals such as zinc, magnesium, aluminum, calcium, titanium, manganese, tin, and nickel.

The ratio of the basic dye to the color developer is generally 1.0 to 5.0 parts by weight, preferably 1.5 to 3.0 parts by weight of the color developer to 1 part by weight of the dye. .

It should be noted that, of course, two or more of the basic dye and the color developer may be used in combination as necessary.

In addition to basic dyes and color developers, inorganic pigments may be added to the heat-sensitive recording material. Examples of inorganic pigments include calcium carbonate, aluminum hydroxide, talc, kaolin, diatomaceous earth, titanium oxide, magnesium carbonate, silicon oxide, and the like. In addition, to prevent the recording layer from sticking when it comes into contact with a recording head, etc.,
Dispersions of salts such as zinc stearate and calcium stearate may also be added.

Furthermore, in order to improve adhesion to substrates such as paper, heat-sensitive recording materials use binders, and when water is used as a dispersion medium, starches, hydroxycellulose, carboxymethyl cellulose, gelatin, casein, polyvinyl alcohol, and styrene-anhydrous are used as binders. Maleic acid copolymer etc. should be added in an amount of 2 to 40% by weight, preferably 5 to 25% by weight of the total solid matter. On the other hand, if an organic solvent such as toluene or methyl ethyl ketone is used as a dispersion medium, methyl methacrylate resin or the like should be added to the total solid content. 10-50% by weight of the mold, preferably 20-40%
% by weight can be used. Of course, the binder is not limited to these.

Generally known methods can be used to prepare a heat-sensitive recording material using the various heat-sensitive coloring layer forming components described above. For example, basic dyes, color developers, sensitizers,
Inorganic pigments and other additives are added to an aqueous medium together with a binder or a basic dye alone, and the remaining components are mixed together with an aqueous polyvinyl alcohol solution, etc., and processed using a ball mill, attritor, etc. Grind and disperse using a dispersion machine and prepare as a coating liquid. Then,
The respective dispersions are mixed to prepare a heat-sensitive coloring layer, which is coated on a support such as paper according to a conventionally known technique and dried.

The amount of coating liquid applied to a support such as paper is not particularly limited, and is generally 2 to 12 g/dry weight.
m, preferably in the range of 3 to 10 g/Td.

Note that the support is not particularly limited, and paper, synthetic fiber paper, synthetic resin film, etc. can be used as appropriate.

Generally speaking, it is also possible to provide an overcoat layer on the recording layer for the purpose of protecting the recording layer, and it is of course possible to provide an undercoat layer on the support. Various known techniques can be added.

[Effects of the Invention] Thus, the heat-sensitive recording material produced using the additive of the present invention has excellent high-speed recording properties and has well-balanced properties in terms of quality with little reduction in whiteness.

[Example] Hereinafter, examples of synthesis of a hydantoin compound, which is an additive for heat-sensitive recording materials according to the present invention, and examples of its use will be specifically described. However, these are examples to facilitate understanding of the present invention, and the present invention is of course not limited to these, and is not limited in any way by these.

(Medicine 1) Synthesis of 3-(2-vinyloxyethyl) to hydantoin A 1 g separable flask equipped with a thermometer, a reflux condenser, and an accompaniment was set in a constant temperature bath.

Dimethylformamide 400! n! , hydantoin 50
．． Add 0 tJ (0.50 mo1), 53.3 g (0.50 mon) of 2-chloroethyl vinyl ether, and 34.69 (0.25 mof) of potassium carbonate.
The reaction was carried out at 0°C for 2 hours.

After the reaction solution was filtered off, the solvent was distilled off under reduced pressure, and the resulting crude crystals were recrystallized from water (200 rnI) to give 3-(2-vinyloxyethyl)-hydantoin 70.09% (yield: 81.0%). 4%).

Melting point: 282-83°C (uncorrected).

Elemental analysis value: CHN O Real II 49,28 5.99 16.61 28.
12 Theoretical value 49.41 5.92 16.46 28
．． 21 Large dust cloud [Dispersion liquid A] 3-(N-cyclohexyl-N-methylamine)-6-
Methyl-7-phenylaminofluorane
25 parts by weight 15% polyvinylal]-ol aqueous solution 25 parts by weight Water 50 parts by weight [Dispersion B] 2.2-bis(4-hydroxyphenyl)propane
25 parts by weight 15% polyvinyl alcohol aqueous solution 25 parts by weight Water 50 parts by weight [Dispersion
C] 3-(2-vinyloxyethyl)-hydantoin
25 parts by weight 15% polyvinyl alcohol aqueous solution 25 parts by weight Water 50 parts by weight Each of the above compositions was ground and dispersed for 24 hours using a paint conditioner to prepare dispersions A1B and C.

Next, [A] 10 parts by weight of liquid, [8] 25 parts by weight of liquid, [
C] 30 parts by weight of solution, 30 parts by weight of 50% calcium carbonate dispersion, and 5 parts by weight of 15% polyvinyl alcohol were mixed and stirred to prepare a coating liquid. The obtained coating liquid was applied to a base paper of 50 s/m using a wire bar so that the dry coating weight was 10 q/Trt and allowed to dry.

Example 2 [Dispersion liquid Dl 3-(2-ethyloxyethyl)-hydantoin
25 parts by weight 15% polyvinylalcohol aqueous solution 25 parts by weight water 50 parts by weight Dispersion [Dl was prepared in the same manner as in Example 1, Example 1 except that [C] liquid was used instead of [Dl liquid] Thermosensitive recording paper was prepared in the same manner as above.

Example 3 [Dispersion E] 3-(2-ethyloxyphenyl)-hydantoin
25 parts by weight 15% polyvinyl alcohol aqueous solution 25 parts by weight Water 50 parts dispersion [E]
was prepared in the same manner as in Example 1, and a thermosensitive recording paper was produced in the same manner as in Example 1, except that liquid [E] was used instead of liquid [C].

Comparative Example A thermosensitive recording paper was prepared in the same manner as in Example 1 except that stearic acid amide was used instead of 3-(2-vinyloxyethyl)-hydantoin in dispersion [C].

The four types of heat-sensitive recording materials prepared in this way were tested at a temperature of 110°C using a thermal gradient tester.
A pressure of J/ci was applied for 0.2 seconds, and the black color image was measured using a Macbeth densitometer.

Moreover, the whiteness was measured using a Hunter whiteness meter.

In addition, in the thermal stability test, the four types of samples obtained were
The whiteness after standing at 0° C. for 24 hours was measured using a Hunter whiteness meter.

The results are shown in Table 1.

From Table 1, it can be seen that in Examples 1 to 3, the color density and thermal stability are well balanced compared to the comparative examples.

Claims (1)

[Claims] 1) From a hydantoin derivative represented by the general formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] (In the formula, R represents an alkyl group, a vinyl group, or an aryl group.) Additive for heat-sensitive recording materials.