JPS6149629B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating time course indicator at a constant temperature. A conventionally known method for understanding the elapsed heating time and heating history at a constant temperature is to use volatile dyes that melt, evaporate, or sublimate when heated, and measure the hue and density over time from dark to light. By coexisting a volatile pigment that melts, evaporates, or sublimates over time when heated, and a non-vaporizable pigment that does not melt and evaporate at the heating temperature, or whose rate of melting and evaporation is extremely slow even if it melts and evaporates. , a method of determining the temperature based on a change in hue at the heating temperature is known. However, all of these methods utilize the fading property of volatile dyes at a constant temperature, and it is difficult to expect a significant change in hue, and therefore it is also difficult to distinguish between long and short heating times. . In order to solve these problems, we developed a display material in which an electron-donating color-forming organic compound such as leucomethylene blue or malachite green lactone coexists with a dye that melts and evaporates or sublimates, and a carboxyl group, a sulfone group, We have proposed an invention relating to a heating time course indicator in which resins having phenolic hydroxyl groups and the like coexist.

The present invention has been made in order to make it easier to discriminate hues more effectively than the above-described invention.

That is, the present invention particularly focuses on the coexistence of an electron-donating color-forming organic compound (hereinafter referred to as a color-forming dye) and a dye that melts and evaporates or sublimates (hereinafter referred to as a vaporizable dye). It is characterized by using a vaporizable dye having the following structures (a) to (e) that melts, evaporates, or sublimates under heating conditions necessary for color development of the chromogenic dye.

(a) R ₁ to _{R 4} : (hydrogen, C ₁ to C ₈ alkyl group, phenyl group, hydroxyethyl group) X: (hydrogen, methoxy group, ethoxy group, phenoxy group) (b) R ₁ to _{R 4} : (hydrogen, C ₁ to C ₃ alkyl group, phenyl group, hydroxyethyl group) X: (hydrogen, methoxy group, phenoxy group) (c) R ₁ , R ₂ : (hydrogen, C ₁ to C ₄ alkyl group, hydroxyethyl group) (d) R ₁ : (hydrogen, C ₁ to C ₃ alkyl group, phenyl group) X: (hydrogen, nitro group, methyl group, methyl carboxyl group) (e) X: (hydrogen, _C1 - _C3 alkyl group, methoxy group, ethoxy group) Volatile dyes include disperse dyes, oil-soluble dyes, some basic dyes, benzidine dyes, mordant dyes, vat dyes, etc. , these can also be used, but among them, dyes with the above structure (disperse dyes or oil-soluble dyes) as vaporizable dyes used in heating time course display materials bring about further hue changes,
I discovered that it is also extremely easy to distinguish.

In the present invention, when a chromogenic dye and a vaporizable dye are allowed to coexist, it is preferable that the chromogenic dye and the vaporizable dye have a complementary color relationship. For example, if the chromogenic dye has a blue hue, if a dye with a yellow or red hue is used as the vaporizable dye, it can be easily distinguished by the change in hue. Naturally, if the chromogenic dye and the vaporizable dye are the same or have similar hues, it will be difficult to distinguish them.

The dye having the above structure is a dye that is relatively easy to melt, evaporate, or sublimate, and when coexisting with a color-forming dye, the color fades gradually as the heating time elapses, which is the exact opposite of the increase in the concentration of the color-forming dye. It can give a very clear hue change.

Specific examples of such volatile dyes include 1-methylaminoanthraquinone, 1-(N-hydroxyethyl)aminoanthraquinone, 1-amino-4-hydroxyanthraquinone, 1,4-diaminoanthraquinone, 1-amino-4-methyl Aminoanthraquinone, 1-methylamino-4-
Hydroxyethylaminoanthraquinone, 1-amino-2-carbamoyl-4-methylaminoanthraquinone, 1.4-dimethylaminoanthraquinone, 1-amino-4-phenylaminoanthraquinone, 1-methylamino-4-phenylaminoanthraquinone, 1- Amino-2-phenoxy-4
-Hydroxyanthraquinone, 3-methyl-4
(2'-nitro-4'-methyl), phenylazopyrazolone, 1-phenyl-3-methyl-4(4'-methylcarboxy)phenylazopyrazolone, 4-amino-4'-nitro-azobenzene, 4 -(N-ethyl-N'-hydroxyethyl)amino-4'nitroazobenzene, 4-(N,N'-dihydroxyethyl)amino-4'-nitroazobenzene, 4-(N
-butyl-N'-hydroxyethyl)amino-4'-
Examples include nitroazobenzene, 1-phenylazo-2-naphthol, 0-methoxyphenylazonaphthol, and the like. In addition, as coloring pigments used in combination with these, malachite green lactone,
Crystal violet lactone, crystal violet carbinol, N-(2,3-dichlorophenyl)leucouramine, N-phenyluramine, Rhodamine B lactam, benzoylleucomethylene blue, 2-(phenyliminoethanezylidene)- 3.3-dimethylindoline, N-3.3-
Trimethylindolinobenzospiropyran, 3-
Diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-6-benzyloxyfluoran, 1,2-benz-6-diethylaminofluoran, etc. can be used.

In addition, when these vaporizable dyes and color-forming dyes are allowed to coexist, if resins containing acidic groups such as sulfone groups, carboxyl groups, and phenolic hydroxyl groups are co-existed, the color-forming dyes will develop color in stages, so the hue will not change. When will it become clearer?

By using the present invention, it can be widely used as various heating time elapse indicators such as heating time display indicators for various heat sterilization and sterilization systems.

Examples are described below.

<Example 1> (1) An ink consisting of the following formulation was prepared using a ball mill. …(a) Water-soluble copolymer consisting of ethyl acrylate monomer and ethylene sulfonic acid monomer in a molar ratio of 20:1 (degree of polymerization 1500) …30 parts by weight Isopropyl alcohol …40 parts by weight Water …28.5 〃 Benzoylleucomethylene blue
………1 〃 1-Methylaminoanthraquinone 0.5 〃 (CI Solvent Red (1) Total 100.0 parts by weight (2) Ink (A) prepared in (1) was applied in the usual manner onto 60 g/m ² coated paper. Gravure printing was performed to obtain printed paper.

(3) The printed paper obtained in (2) was placed on a hot plate with a surface temperature of 150°C, and when the hue change was checked every 2 hours, the printed paper, which had a red hue before heating, gradually turned red. decreases and becomes more blueish, 10
After some time, it took on a beautiful clear methylene blue hue.

(4) An ink having the following formulation was prepared by ball milling as a comparative example.

Water-soluble copolymer consisting of ethyl acrylate monomer and ethylene sulfonic acid monomer in a molar ratio of 20:1 (degree of polymerization 1500)...30 parts by weight Isopropyl alcohol...40 Water...28.5 Benzoylleucomethylene blue...1 1.4-dihydroxy, 2 - Sulfonylanthraquinone (CI, Pigment Violet 5) 0.5 total 100.0 parts by weight (5) Using this ink (4), the same test as (2) and (3) was conducted, and after 10 hours, methylene blue It did not show any blue color and remained red.

☆This 1,4-dihydroxy, 2-sulfonylanthraquinone is a sublimable dye, but it does not have the structure claimed in the claims and is not suitable as an indicator.

<Example 2> An ink consisting of the following formulation was prepared using a ball mill. ...(a) Water-soluble copolymer consisting of ethyl acrylate monomer and ethylene sulfonic acid monomer in a molar ratio of 20:1 (degree of polymerization 1500) 30 parts by weight Isopropyl alcohol 40 〃 Water 28.5 〃 Benzoylleucomethylene blue 1 〃 1-Methylaminoanthraquinone (CI Solvent Red 111) 0.5 〃Total 100.0 parts by weight (2) Perform gravure printing with the ink (A) prepared in (1) on 60 g/m ² coated paper using the usual method to obtain printing paper. Ta.

(3) The printed paper obtained in (2) was placed on a hot plate with a surface temperature of 150°C, and when the hue change was checked every 2 hours, the printed paper, which had a red hue before heating, gradually turned red. The color decreased, and the blue color increased, and after 10 hours, it took on a beautiful clear methylene blue hue.

<Example 3> (1) An ink consisting of the following formulation was prepared by ball milling. ...(a) Water-soluble copolymer consisting of ethyl acrylate monomer and ethylene sulfonic acid monomer in a molar ratio of 20:1 (degree of polymerization 1500) 30 parts by weight Isopropyl alcohol 40 〃 Water 28.5 〃 Benzoylleucomethylene blue 1 〃 1-phenylazo-2 - Naphthol (CI Solvent Yellow 14) 0.5 Total 100.0 parts by weight (2) The ink (A) prepared in (1) was printed as in Example 1 to obtain printed paper.

(3) When the printed paper obtained in (2) was left on a 150℃ heating plate and the hue was checked every 2 hours, the printed paper, which had a yellow hue before heating, gradually became less yellow. However, the blue color increased, and after 10 hours it took on a beautiful clear methylene blue hue.

<Example 4> (1) An ink consisting of the following formulation was prepared using a ball mill. …(A) Acrylic acid ester resin…20 parts by weight Isopropyl alcohol…40 Water…38.5 Rhodamine B-lactam…1 1.4-dimethylaminoanthraquinone (CI Disperse Blue 14) 0.5 Total 100.0 parts by weight (2) The ink (a) prepared in 1) was printed as in Example 1 to obtain printed paper.

(3) The printed paper obtained in (2) was left on a 150℃ heating plate and the hue was checked every 2 hours. The printed paper, which had a blue hue before heating, gradually turned blue. The color decreased and the red color increased, and after 10 hours, it took on a clear rhodamine B red color.

Claims (1)

[Scope of Claims] 1. An electron-donating color-forming organic compound that changes from colorless or very pale to dark color over time when heated;
A heating time lapse display characterized by coexisting with a dye having any of the following structures (a) to (e) that melts, evaporates, or sublimates under the same heating conditions as this heating. (stomach) R ₁ , R ₂ , R ₃ , R ₄ : hydrogen, C ₁ to C ₈ alkyl group,
Phenyl group, hydroxyethyl group X: hydrogen, methoxy group, ethoxy group, phenoxy group (b) R ₁ , R ₂ : Hydrogen, C ₁ to C ₃ alkyl group, phenyl group, hydroxyethyl group X: Hydrogen, methoxy group, phenoxy group (c) R ₁ , R ₂ : Hydrogen, C ₁ to C ₄ alkyl group, hydroxyethyl group (d) R ₁ : Hydrogen, C ₁ to C ₃ alkyl group, phenyl group X: Hydrogen, nitro group, methyl group, methyl carboxyl group (e) X: hydrogen, _C1 to _C3 alkyl group, methoxy group,
The heating time elapsed display according to claim 1, characterized in that a resin having an acidic group such as an ethoxy group 2, a sulfone group, a carboxyl group, or a phenolic hydroxyl group is present.