KR20200074366A - Printed, air activated Time-Temperature Indicators - Google Patents

Abstract

The present invention relates to a time-temperature history indicator including oxidation-reduction dyes, thermally conductive fluids, antioxidants, sulfurhydryl compounds, and solvents. Accordingly, the time-temperature history indicator is directly printed and used on various supports, such as paper, plastic film, glass, and metal; is produced in the form of a label; does not need to go through the UV activation step, has various lifespans; accurately indicates the quality change according to oxygen, temperature, time, and the like by allowing a temperature dependence of food attached by TTI to correspond to a reaction rate of TTI when food is stored and distributed; and is manufactured through a simple printing technique using inorganic materials. Thus, costs are low and, storage is convenient, and a separate storage device for storage is unnecessary.

Description

Air-activated printable time-temperature history indicators {Printed, air activated Time-Temperature Indicators}

The present invention relates to printable time-temperature history indicators, which are maintained in a reduced state, capable of controlling the distribution period, and do not require UV activation and can be activated by air. It is about temperature history indicator.

Recently, as consumers' interest in food safety and management increases, the importance of intelligent packaging that can check food quality information has emerged. In particular, Time-Temperature Indicators (TTI), which can be attached to the outside of packaged food and show the quality of food through color change, have been continuously developed for decades, and many types of TTI are currently in food. And is commercialized. However, despite the many advantages of TTI that appeared long ago, it has been pointed out that the application of TTI needs to be supplemented in practical terms due to insufficient application.

In the present invention, it was intended to improve the activation method for a print-type TTI known to be the most practical. In the case of TTI developed by Galagans et al., a method to replace the process of reducing methylene blue by UV using a redox material was developed. The activation process by UV is basically a reaction to reduce methylene blue, and if an antioxidant is used, the reduction reaction may be more easily generated (Snehalatha, Rajanna, & Saiprakash, 1997).

In the medical field, a technique for reducing methylene blue to leuco methylene blue using an antioxidant has been developed. The combination of Methylene blue and antioxidants L-cysteine, glutathione, and ascorbic acid could be reduced to Leuco-methylene blue. Among them, L-ascorbic acid and L-cysteine were mixed together in an appropriate ratio, and it was confirmed that the most stable leuco-MB was maintained when reducing methylene blue (Wulfert, Atkinson, & Salomon, 2001). Also, according to Takashi et al., when using antioxidants, mixing two or more antioxidants showed a much better effect than using only one. In particular, it was said that ascorbic acid has a pro-oxidative effect when water is present (Kadoya, 2012). In addition, sulfhydryl amino-acids such as cysteine were very effective in reducing methylene blue (Black, 1947; Seno, Kousaka, & Kise, 1979).

Referring to the operation mechanism (FIG. 1), Methylene blue is reduced to leuco Methylene blue using the antioxidants L-ascorbic acid and L-cysteine (step 1). In that state, ink paste is prepared and then printed and coated using a silk screen printing technique (step 2). The fabricated TTI returns to its original oxidized form when exposed to air and re-colors (step 3).

When designing and manufacturing time-temperature history indicators, the first thing to consider is to have the indicator show a clear, continuous and irreversible color change as the temperature changes. In addition, the indicator should normally remain inactive and be activated as a rain when attached to the food packaging. The method of activating air exposure is not activated unless it is taken out of the vacuum packaging, so it is stable and cannot react, so it can solve the existing problems, and adjust the amount of antioxidants (L-ascorbic acid, L-cysteine) and humectant glycerol. After preparing a printing ink by dispersing in an organic solvent, printing on a support can produce an air-activated printing time-temperature history indicator.

Many time-temperature history indicators have been developed over the past 50 years, but only a fraction of them are being used due to their inability to meet technical efficacy and commercial needs. As a commercial demand, one of the most important fields of time-temperature hysteresis research is mass production method research to lower the unit cost of the indicator, and a printing method is applied as a method of transferring a pigment material to a support. In the case of OnVu® time-temperature history indicator of Ciba Specialty Chemicals, which was most recently developed, a method of activating by irradiating with ultraviolet rays after transferring a coloring matter to a support using a printing technique is applied. The most important part of the printing technology is highly dependent on physical properties such as viscosity of the printing inks, surface tension, non-foaming property, excellent adhesion, fast drying property, high quality and irreversible. In general, oil-based inks are used for printing non-porous materials, but water-based inks are used for printing porous materials. The reactive layer of the air-activated printable time-temperature hysteresis indicator should be stable, sensitive, and selective. In addition, proper adhesion of the texture-forming agent uniformly applied to the support is an essential element to ensure accurate response of the time-temperature hysteresis indicator. Meanwhile, the color change of the time-temperature history indicator can be adjusted through various physicochemical methods, and the temperature dependence of the food and the temperature dependence of the time-temperature history indicator must match to accurately represent the change in food quality over time. have.

Oxidation-reduction dyes sensitive to oxygen change color by oxidation of reducing dyes by diffusion of oxygen through the barrier film. Lewis (2002) used this to produce a time-temperature hysteresis indicator made of paper and plastic cover saturated with methylene blue, which causes an incremental color change by diffusion of oxygen through the plastic cover. The color change rate and temperature dependence can be controlled according to the film thickness, oxygen permeability, and the like. It is known that the permeability of a polymer film has an effect on the density, molecular weight, crystallinity, elongation, crosslinking degree, plasticizer type and amount, humidity, method of manufacturing the film, type and amount of additives, and film thickness. .

Korean Registered Patent No. 10-1062814

The present invention is intended to provide a time-temperature history indicator that can be used by printing directly on various supports such as paper, plastic film, glass, metal, and the like, and can be produced in a label form.

In addition, the present invention aims to provide a time-temperature history indicator that does not need to go through the UV activation step.

In addition, the present invention aims to provide a time-temperature history indicator having various shelf life.

In addition, the present invention aims to provide a time-temperature history indicator that can accurately represent the quality change according to oxygen, temperature, time, etc. during storage and distribution of foods in such a way that the temperature dependency of the food to which the TTI is attached and the reaction speed of the TTI are the same. Should be

In addition, the present invention aims to provide an inexpensive time-temperature history indicator that can be produced by a simple printing technique using inorganic materials.

In addition, the present invention aims to provide a time-temperature history indicator that is easy to store and does not require a storage device for storage.

1. Air-activated printable time-temperature history ink composition comprising an oxidation-reduction dye, a heat transfer fluid, an antioxidant, a sulfhydryl compound, and a solvent.

2. In the above 1, wherein the oxidation-reduction dye is methylene green, methylene blue, luminol, nitro-fluorenone derivative, azine, osmium phenanthroline dione, catechol-pendant terpyridine, toluene blue, cresyl blue, nile Blue, neutral red, phenazine derivative, thionine, azure A, azure B, azure C, toluidine blue O, acetophenone, metallophthalocyanine, nile blue A, modified transition metal ligand, 1,10-phenanthroline- 5,6-dione, 1,10-phenanthroline-5,6-diol, [Re(pen-dione)(CO)3Cl], [Re(pen-dione)3](PF6)2, poly(metal Loftocyanine), poly(thionine), quinone, diimine, diaminobenzene, diaminopyridine, phenosapronin, phenothiazine, phenoxazine, toluidine blue, brilliant cresyl blue, 3,4-dihydroxy Benzaldehyde, sodium 2,6-dibromophenol-indophenol, sodium o-cresol indophenol, indigotetrasulfonic acid, indigotrisulfonic acid, indigo carmine, indigomonosulfonic acid, safranin T, 2,2 '-Bipyridine (Ru complex), 2,2'-bipyridine (Fe complex), nitrophenanthroline (Fe complex), N-phenylanthranylic acid, 1,10-phenanthroline (Fe complex), N -Ethoxycrisoidine, 5,6-dimethylphenanthroline (Fe complex), o-dianicidine, sodium diphenylamine sulfonate, diphenylbenzidine, difetylamine, viologen, poly(acrylic acid), poly (Azure I), poly(nyle blue A), poly(methylene green), poly(methylene blue), polyaniline, polypyridine, polypyrrole, polythiophene, poly(thieno[3,4-b]thiophene), Poly(3-hexylthiophene), poly(3,4-ethylenedioxypyrrole), poly(isothianaphthene), poly(3,4-ethylenedioxythiophene), poly(difluoroacetylene), poly (4-Dicyanomethylene-4H-cyclopenta[2,1-b;3,4-b']dithiophene), poly(3-(4-fluorophenyl)thiophene) and poly(neutral red) An ink composition for an air activated printable time-temperature history indicator, which is at least one selected from the group consisting of.

3. In the above 1, the heat transfer fluid is glycerol (glycerol), triethanolamine (triethanolamine), ethylenediaminetetraacetic acid (ethylenediaminetetraacetic acid, EDTA), glycine (glycine), L-tyrosine (L-tyrosine), D-ph At least one selected from the group consisting of D-fructose, D-galactose and sodium citrate, the air-activated printable time-temperature hysteresis ink composition.

4. In the above 1, the antioxidant is ascorbic acid (ascorbic acid), tocopherol (tocopherol), beta-carotene (β-carotene), butyl hydroxyanisole (BHA), butyl hydroxy toluene (BHT), Tert -At least one selected from the group consisting of butyl hydroquinone (TBHG) and propyl gallate (PG), an air-activated printable time-temperature hysteresis ink composition.

5. In the above 4, the sulfhydryl compound is selected from the group consisting of methionine, cysteamine, cysteine, homocysteine, S-adenosylmethionine, acetylcysteine, reduced or oxidized glutathione and S-acetyl-glutathione. An ink composition for at least one air activated printable time-temperature history indicator.

6. The method of 1 above, wherein the solvent is at least one selected from the group consisting of distilled water, methanol, ethanol, and acetone, an air-activated printable time-temperature hysteresis ink composition.

7. Forming a printing layer by printing the ink composition of any one of the above 1 to 6 on a support; And drying the printing layer.

8. The method of 7 above, wherein the printing is performed by a silk screen printing method using a silk screen of 200 to 350 mesh, an air activated printing time-temperature history indicator.

9. In the above 7, forming a film layer on the dried print layer; And forming a coating layer on the film layer.

10. The method of 7 above, wherein the film layer is at least one selected from the group consisting of PE, PET, PVC and OPP, an air activated printing time-temperature history indicator.

11. An air activated printable time-temperature history indicator manufactured by the method of any one of 7 to 10 above.

According to an embodiment of the present invention, various supports such as paper, plastic film, glass, metal, etc. can be directly printed and used, and a time-temperature history indicator capable of being manufactured in a label form is provided.

In addition, according to an embodiment of the present invention, there is provided a time-temperature history indicator that does not need to go through the UV activation step.

In addition, according to an embodiment of the present invention, there is provided a time temperature history indicator having various shelf life.

In addition, according to an embodiment of the present invention, the temperature dependence of the temperature dependency of the food to which the TTI is attached and the reaction rate of the TTI are the same, so that the time-temperature that can accurately represent the quality change according to oxygen, temperature, time, etc. during storage and distribution of food Provide a history indicator.

In addition, according to an embodiment of the present invention, it can be manufactured by a simple fritting technique using an inorganic material, thereby providing an inexpensive time-temperature history indicator.

In addition, according to an embodiment of the present invention, it is easy to store and provides a time-temperature history indicator that does not require a storage device for storage.

1 shows the operating principle of the time-temperature history indicator.
Figure 2 shows a brief embodiment of the time-temperature history indicator of the present invention.
Figure 3 shows the color change (including the end point) of the time-temperature history indicator according to the present invention.
4 and 6 (A) is a diagram illustrating a process related to the construction of a manufacturing manual for a time-temperature history indicator according to the present invention.
5 and 6(B) illustrate problems and optimized printing methods according to the printing method of the time-temperature history indicator ink composition according to the present invention.
Figure 7 shows the printability according to the content of the ink Tween 80 and PEG Mn 300.
8 briefly shows the manufacturing process of a time-temperature history indicator according to the present invention.
9 is a schematic diagram of a process related to the construction of a product specification and a user manual of a time-temperature history indicator according to the present invention.
10 shows the standard and color change of the time-temperature history indicator according to the present invention.
11 shows the color change of 50 products immediately after the production of the time-temperature history indicator according to the present invention.
12 shows the color change of 50 products after 2 months storage of the time-temperature history indicator according to the present invention.
E) It represents the value.
14 shows an activation energy value of a time-temperature history indicator according to an embodiment of the present invention.
15 and 16 show activation energies and shelf life of various food groups.
Fig. 17 shows the result data of the sticker-type adhesion performance test of the time-temperature history indicator of the present invention.
Figure 18 shows the results of the test results of the bonding ability of the time-temperature history indicator of the present invention.
19 shows the results of the silicone adhesion performance test results of the time-temperature hysteresis indicator of the present invention.
Figure 20 shows the results of the test results of the double-sided tape adhesion performance of the time-temperature history indicator of the present invention.

The present invention relates to a time-history indicator, and includes an oxidation-reduction dye, a heat transfer fluid, an antioxidant, a sulfhydryl compound, and a solvent, and can be used by printing directly on various supports such as paper, plastic film, glass, metal, etc. It is possible to manufacture in the form of a label, there is no need to go through the UV activation step, it has various shelf life, and the temperature dependence of the food to which the TTI is attached and the reaction speed of the TTI are the same so that the oxygen during storage and distribution of food, It can accurately represent the quality change according to temperature, time, etc., and can be manufactured using a simple printing technique using inorganic materials, so it is inexpensive, easy to store, and does not require a storage device for storage. It is about.

Hereinafter, the present invention will be described in detail.

The present invention is an air-activated printable time-temperature integrator (TTI, hereinafter referred to as'TTI') ink composition comprising an oxidation-reduction dye, a heat transfer fluid, an antioxidant, a sulfhydryl compound, and a solvent. to provide.

The existing UV-activated printing-type ink composition for time-temperature hysteresis indicators required a UV activation process, and a process of attaching a UV blocking film to prevent additional UV irradiation after UV irradiation was absolutely necessary. However, the present invention can activate the time-temperature history indicator by reduction according to the action of the antioxidant and the sulfhydryl compound without UV irradiation by adding a combination of an antioxidant and a sulfhydryl compound, so that the UV activation step, UV blocking No film attachment is necessary. Moreover, the shelf life can be controlled by varying the blending ratio of antioxidant and sulfhydryl.

The oxidation-reduction dye is used in a conventional TTI and can be used without limitation as long as it is an oxidation-reduction dye in which a reducing dye is oxidized and the color changes by diffusion of oxygen. Specifically, the methylene green, methylene blue, luminol, nitro-fluorenone derivative, azine, osmium phenanthroline dione, catechol-pendant terpyridine, toluene blue, cresyl blue, nile blue, neutral red, phenazine derivative, thio Nin, Azur A, Azur B, Azur C, Toluidine Blue O, Acetophenone, Metallophthalocyanine, Nile Blue A, Modified Transition Metal Ligand, 1,10-phenanthroline-5,6-dione, 1,10- Phenanthroline-5,6-diol, [Re(phen-dione)(CO)3Cl], [Re(phen-dione)3](PF6)2, poly(metallophthalocyanine), poly(thionine), Quinone, diimine, diaminobenzene, diaminopyridine, phenosapronin, phenothiazine, phenoxazine, toluidine blue, brilliant cresyl blue, 3,4-dihydroxybenzaldehyde, sodium 2,6-dibromo Phenol-indophenol, sodium o-cresol indophenol, indigotetrasulfonic acid, indigotrisulfonic acid, indigo carmine, indigomonosulfonic acid, safranin T, 2,2'-bipyridine (Ru complex), 2 ,2'-bipyridine (Fe complex), nitrophenanthroline (Fe complex), N-phenylanthranylic acid, 1,10-phenanthroline (Fe complex), N-ethoxycriisodine, 5,6 -Dimethylphenanthroline (Fe complex), o-dianicidine, sodium diphenylamine sulfonate, diphenylbenzidine, difetylamine, viologen, poly(acrylic acid), poly(azur I), poly(Nile Blue A ), poly(methylene green), poly(methylene blue), polyaniline, polypyridine, polypyrrole, polythiophene, poly(thieno[3,4-b]thiophene), poly(3-hexylthiophene), poly (3,4-ethylenedioxypyrrole), poly(isothianaphthene), poly(3,4-ethylenedioxythiophene), poly(difluoroacetylene), poly(4-dicyanomethylene-4H-cyclo Penta[2,1-b;3,4-b']dithiophene), poly(3-(4-fluorophenyl)thiophene), poly(neutral red), and the like can be used.

According to an embodiment of the present invention, the oxidation-reduction dye may be methylene blue (MB). Methylene blue is oxidized by oxygen and becomes blue. The oxidized methylene blue receives electrons from the cathode and is reduced to give a colorless color. When the oxidation rate by oxygen is faster than the electrochemical reduction rate, methylene blue becomes blue. That is, it is possible to check whether oxygen is introduced through the color change of the redox dye according to the redox state.

The oxidation-reduction dye is preferably included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the ink composition, and when its content is less than 0.01 parts by weight, it cannot exhibit a color as an indicator, and if it is within the aforementioned range, When the color is measured with a colorimeter, it is preferable to always feel the same indication color.

According to an embodiment of the present invention, the oxidation-reduction dye included in the time-history indicator of the present invention may be less than or similar to the content of the antioxidant described below. When the content of the antioxidant is higher than that of the oxidation-reduction dye, a problem that the end point of the time-history indicator becomes unstable may occur (Tables 7 and 8).

Water remains the most efficient and inexpensive heat transfer fluid, but there are some chemical and physical limitations that can affect thermal performance, system reliability and maintenance costs. As a result, many alternative fluids have been developed that promote effective heat transfer but improve the basic properties of water, specifically glycerol, triethanolamine, ethylenediaminetetraacetic acid (EDTA), glycine, L -L-tyrosine, D-fructose, D-galactose, sodium citrate, etc. may be used.

Thermally conductive fluids can generally transfer thermal energy efficiently and can also be used as antifreeze, coolant, etc. In the present invention, by using the heat-conducting fluid, the activation energy of the TTI is adjusted so that the temperature dependence of the food to which the TTI is attached and the reaction speed of the TTI are the same, so that the quality change according to oxygen, temperature, time, etc. during storage and distribution of food is accurately performed. You can make it visible. According to an embodiment of the present invention, the heat-conducting fluid may be glycerol, and when glycerol is used, it is possible to more easily control activation energy of TTI.

The heat-conducting fluid is not limited thereto, and may be included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the ink composition, and when the content is less than 0.01 part by weight, an activation reaction cannot be initiated due to failure to generate sufficient electrons, 10 When it exceeds the weight part, a reversible decolorization reaction occurs, and it cannot function properly as an indicator. According to an embodiment of the present invention, the heat-conducting fluid may have a content of 1 to 10 parts by weight contained in the ink for time-temperature history indicator. When included within the above range, the activation energy of the time-temperature hysteresis indicator is not low, so color changes can be stably generated.

The ink composition for time-temperature history indicators according to the present invention includes a combination of an antioxidant and a sulfhydryl compound. By controlling the content of the antioxidant and the sulfhydryl compound in various ways, the shelf life of the time-temperature history indicator can be adjusted, which can be used to accurately display the shelf life of various foods. In addition, by including a combination of an antioxidant and a sulfhydryl compound in the composition of the present invention, it is possible to activate the time-temperature history indicator without having to go through the UV activation step, and furthermore, to prevent color change errors due to overlapping irradiation of UV. To do this, a time-temperature hysteresis indicator without the need to add a UV-blocking film can be produced.

According to an embodiment of the present invention, it was confirmed that when the antioxidant and the sulfhydryl compound were included in a certain ratio, a time-temperature history indicator having a color change period very similar to a shelf life of food was produced, It was indirectly confirmed that it can be applied to other foods by controlling the ratio of the antioxidant and the sulfhydryl compound. That is, the present invention was confirmed that the time-history clock capable of accurately checking the distribution period of various foods when the combination ratio of the sulfedrill compound and the antioxidant is various.

The antioxidants include ascorbic acid, tocopherol, beta-carotene, butylhydroxyanisole (BHA), butylhydroxytoluene (BHT), and tert-butylhydroquinone (TBHG) ), propyl gallate (PG), etc. may be used, and the content may be included in 10 to 15 parts by weight based on 100 parts by weight of the ink composition, but is not limited thereto.

The sulfhydryl compound may include methionine, cysteamine, cysteine, homocysteine, S-adenosylmethionine, acetylcysteine, reduced or oxidized glutathione, S-acetyl-glutathione, and the content thereof. It can be adjusted in various ways.

According to an embodiment of the present invention, ascorbic acid as an antioxidant, and cysteine as a sulfhydryl compound may be used. In particular, when a combination of these is used, activation of the time-temperature hysteresis indicator and storage stability are shown to be very excellent. .

The time-temperature history indicator ink composition according to the present invention may further include a solvent and/or a polymer material capable of controlling the physical properties of the composition. At this time, the solvent and the polymer material may be used without limitation, as long as it is a solvent and a high-capacity material used in ink. For example, zein, gliadin, hordein, etc. may be used as the polymer material, and distilled water, methanol, ethanol, acetone, etc. may be used as the solvent. In particular, in the case of Jane, it is soluble in an organic solvent and does not dissolve in water, thereby preventing the internal components from spreading out, and at the same time, giving the ink a viscosity to influence the printability. The polymer material and the solvent may be included in 1 to 30 parts by weight and 40 to 100 parts by weight, respectively, for 100 parts by weight of the ink composition for optimal ink properties that can be printed on the food packaging material, but are not limited thereto.

The air-activated printing type TTI ink composition of the present invention as described above is printed on a conventional food packaging material, and has appropriate physical properties as an ink to be printed on the food packaging material.

In addition, the present invention provides a method of manufacturing an air-activated printing type TTI using the ink composition as described above.

The manufacturing method includes printing the ink composition on a support to form a printing layer and drying the printing layer.

The method of manufacturing the air-activated printed TTI of the present invention will be described with reference to FIG. 2 as follows. Figure 2 shows an air activated printed TTI made in accordance with the present invention. As shown in Fig. 2, the air-activated printing type TTI of the present invention has a printing layer 2 formed on a support 1, and on the printing layer 2, a film layer 3 and a coating layer as necessary. Etc. may be formed.

The support is a material used as a normal food packaging material, and the air-activated printing type TTI ink composition of the present invention is printed on the support to form a printing layer.

At this time, the printing is preferably performed by a silk screen printing method. When the silk screen is printed, it is preferable to use a silk screen of 200 to 350 mesh, and in particular, when the mesh of the silk screen is 240 to 260 mesh, it may be possible to exhibit the most optimal printed material properties, which is better.

The thickness of the printed layer thus formed does not affect the reaction speed or activation of the air activated printing type TTI, but it is preferable to print such that it is about 15 to 30 µm for smooth printing and TTI production, but is not limited thereto.

The method of the present invention includes forming a film layer on the dried printing layer; And forming a coating layer on the film layer.

The film layer prevents the ink used for printing of the TTI from being damaged from the outside by adjusting the type or thickness of the film, and also controls the supply of oxygen to control the distribution period according to the type of food. That is, a product having a long shelf life can be manufactured as a long-term TTI by using a film through which oxygen is slowly permeated, and a product having a short shelf-life can be manufactured as a short-term TTI by using a film having a high oxygen permeation rate. The film layer can be formed using a film such as PE (Polyethylene), PET (Polyethylene terephthalate), PVC (Polyvinyl chloride), OPP (oriented polypropylene), and the oxygen permeability varies depending on the thickness of the film layer, so the TTI In order to control the color change, the film layer may be formed to a thickness of 50 to 80 μm, but is not limited thereto.

In the present invention, the formation of a coating layer may be performed using a conventional coating method, for example, an acetate coating paper may be used to form a coating layer on the film layer.

Method of the present invention comprises the steps of cutting the time-temperature history indicator to the size of the product; And it may further include the step of vacuum packaging, the vacuum packaging may be performed by packaging the time-temperature history indicator in an aluminum pack, but is not limited thereto.

According to the present invention as described above, various supports such as paper, plastic film, glass, metal, and the like can be directly printed and used, can be produced in a label form, does not need to go through the UV activation step, and controls the mixing ratio of the antioxidant Therefore, it has a variety of shelf life, and the temperature dependence of the TTI-attached food and the reaction speed of the TTI are the same, so it can accurately represent the quality change according to oxygen, temperature, time, etc. during storage and distribution of food. It can be manufactured with a simple printing technique, so it is inexpensive, easy to store, and a TTI that does not require a separate storage device for storage can be manufactured.

Hereinafter, the present invention will be described in more detail with the following examples. The following examples are only intended to aid the understanding of the present invention, not to limit the present invention, and it is natural that the scope of the present invention is not limited.

Example

In this study, for the development of a printable Time Temperature Integrator (TTI), the oxidation-reduction dye is reduced to a reduced state (leuco type) by using an antioxidant and a sulfhydryl compound having an oxidation-retarding action. Induced and the oxidation rate of the dye was adjusted through the mixing ratio of the antioxidant and the sulfhydryl compound.

Oxidation-reduction dyes (eg Methlylene blue; MB) are usually present in the oxidized blue state in the air.

The time-history indicator according to the present invention was made of a printing ink made of MB in a reduced state (Leuco type; white) using an antioxidant and a sulfhydryl compound, using a silk screen printer selected as an optimal printing method. A printed TTI was produced (see Figure 3).

In the following, a detailed description of a time-history indicator, a comparative example thereof, and a user manual according to the present invention will be described.

1. Construction of TTI manufacturing manual

Looking at the entire process for the commercialization of TTI, management including purchasing and sales should be performed at the raw material, process, and product level (Fig. 4). First, the manufacturing manual was constructed as follows for the range including raw materials and processes.

Comparative example: Standard print TTI-1st generation

1) Raw materials

Methylene blue trihydrate 98.5%, Glycerol, Sodium Alginate, TiO ₂ , Tween 80

Reagent name Where to buy standard keep Methylene blue trihydrate, 98.5% SAMCHUN 500g (CAS 7220-79-3) Room temperature Glycerol Sigma Aldrich 500ml (CAS 56-81-5) Room temperature Sodium Alginate DUKSAN 500g (CAS 9005-38-3) Room temperature TiO ₂ Sigma Aldrich 100 g (CAS 13463-67-7) Room temperature Tween 80 SAMCHUN 500g (9005-65-6) Room temperature

2) Manufacturing method and process

After mixing the raw materials and performing the process of adding adhesive ability after printing and packaging, 1000 TTIs/day TTIs were produced.

If the raw material formulation is described in more detail, in the first step, 0.1 g of MB, glycerol, 90 ml of distilled water and TiO ₂ are placed in a beaker and dissolved for 15 minutes using an ultrasonic stirrer. Then, in the second step, 3 g of sodium alginate was added to the previously dissolved ink and dissolved in a Stirrer water bath at 70° C. for 45 minutes. In the final step 3, the sodium alginate in the previously prepared ink was well dispersed and dissolved, and then TTI 80 was prepared by adding 5 g of Tween 80 and 10 g of Polyethylene glycol Mn300.

There are certain requirements to be met in order to obtain the best screen printing print quality. These include plate properties (compressibility, porosity and ink solubility, wettability, etc.) and ink properties (viscosity, viscosity, ink evaporation rate, drying, etc.) (Hrehorova, Pekarovicova, & Fleming, 2006). As a result of manufacturing the TTI by screen printing, there were problems of the degree of deposit on the printing film, clarity, and clogging of the printing network.

The printing process includes silk screen printing, offset printing, and gravure printing, which are known in the art. As a result of printing each of these printing methods in order to identify a printing method suitable for the printed TTI, the silk screen printing method prints the printed TTI. When it was found to be the most suitable (Fig. 5).

3) Determination of printing method and mesh size

When printing the print-type TTI according to the present invention on a silk screen, the mesh of the silk screen was changed to 200, 250, 300 and the amount of ink was varied to check whether the transfer amount of the ink was changed according to the mesh size of the silk screen. After fixing, a QR code was printed on the silk screen.

As a result, it was found that the transfer amount of ink was changed according to the mesh size, and the most optimized ink transfer amount was shown when using a 250 mesh silk screen (see FIGS. 5 and 6 ).

4) Printing and packaging

When the printing and packaging described above are described in more detail, the printing and packaging steps can be divided into three steps: printing, coating, and packaging. In the printing step, a predetermined amount of ink is poured onto the silk screen and printed on PVC sticker paper. In the next coating step, the printed TTI is coated with a UV transmissive film. In the next packaging step, the finished printed TTI is packaged and stored in vacuum nitrogen using a UV-impermeable aluminum pack so that it can be teared off if necessary.

5) 1st generation printable TTI errors and measures

When the first generation printed TTI was manufactured and activated through UV irradiation, the reaction rate due to the oxidation-reduction reaction was too fast, and an error occurred in the control of the expiration date and the activation energy (Ea), and the following measures were taken. .

Raw material error measure TiO ₂ Inhibit uniform printing and diversification of printing methods Remove TiO ₂ and replace with antioxidant UV activated Activation takes time and inhibits use of various films Conversion to oxidation-reduction reaction using antioxidant rather than UV activation fair error measure mix Discoloration due to composition non-uniformity per sample and role of photosensitizer TiO2 removal UV irradiation Discoloration by UV after delay and reaching end point Skip UV activation process using antioxidants ascorbic acid and L-cysteine

Example: Standard printing TTI-2nd generation

1) Raw materials

Methylene blue trihydrate 98.5%, Glycerol, Sodium Alginate, Tween 80, PEG 300, Ascorbic acid 99.5%, L-Cysteine.

Reagent name Where to buy standard keep Methylene blue trihydrate, 98.5% SAMCHUN 500g (CAS 7220-79-3) Room temperature Glycerol Sigma Aldrich 500ml (CAS 56-81-5) Room temperature Sodium Alginate DUKSAN 500g (CAS 9005-38-3) Room temperature Tween 80 SAMCHUN 500g (9005-65-6) Room temperature Polyethylene Glycol Mn 300 Sigma Aldrich 1Kg (CAS 25322-68-3) Room temperature Ascorbic acid 99.5% SAMCHUN 500 g (CAS No. 50-81-7) Room temperature L-Cysteine, 99% SAMCHUN 100g (P.NO.c2191) Room temperature

2) Manufacturing method and process

After mixing the raw materials and performing the process of adding adhesive ability after printing and packaging, 1000 TTIs/day TTIs were produced.

If the raw material formulation is described more specifically, in the first step, 0.2 g of MB, 1 g of glycerol, and 100 ml of distilled water are added and dissolved using a stirrer for 15 minutes. Then, 4 g of sodium alginate was added to the previously dissolved ink and dissolved in a stirrer water bath at 75°C for 30 minutes. Then, in the second step, 1.75 g of antioxidant ascorbic acid and 0.35 g of cysteine were added to a small beaker, 15 ml of distilled water was added, and then dissolved in a sonicator for 30 minutes. Then, the solution in which the antioxidant is well dissolved is added to the ink prepared above and mixed well in the ultrasonic stirrer for 15 minutes. In the last third step, 5 g of Tween 80 and 10 g of PEG were added and mixed for 15 minutes using an ultrasonic stirrer to prepare a TTI ink.

The third step was to solve the problems that occurred during the production of the first generation TTI, specifically, it was necessary to improve the properties of the TTI ink to solve the problems of the first generation TTI. The addition of emulsifiers was devised as a method for improving the physical properties, and the most important thing in selecting the emulsifiers was to consider the fact that the printability should be improved while not affecting the redox reaction of the ink. The typical non-ionic detergents used in this example, tween 80 and polyethylene glycol (PEG), were selected because the above conditions were frequently used as an emulsifier to improve ink printability (Jones & Nickless, 1978). The printability was compared when 1 to 5 g of Tween 80 and 2 to 10 g of PEG were added at a ratio of 1:2. As a result, when 5 g of Tween 80 and 10 g of PEG were added, it was confirmed that both the degree of clarity, clarity, and drying properties were improved (FIG. 7: Tween 80 and PEG were added in order of 1 g, 2 g, 3 g and 6g, 5g and 10g).

3) Determination of printing method and mesh size

For silk screen selection and mesh size, the optimum value obtained in the comparative example was used (that is, the printing method was silk screen printing, the mesh was 250).

4) Printing and packaging

Printing and packaging can be specifically divided into four steps: printing, coating, cutting and packaging. In the printing step, the previously prepared ink is poured onto a silk screen of a certain amount of 250 mesh and printed on PVC sticker paper. Then, drying is performed until the printed part is completely dried using a dryer. In the coating step, a polyethylene terephthalate (PET) cover film is placed on the printed TTI and coated with Acetate coated paper. In the cutting stage, a large amount of printed TTI printed paper is cut with a cutting plotter according to the printed TTI standard. In the packaging step, the manufactured printed TTI is vacuum-packed in an aluminum pack to be stored and teared if necessary (see FIG. 8).

5) Manufacturing Production Management

step Device management Task management Cleaning safety management Raw material formulation Ultrasonic stirrer
1 time consumption (15 minutes), electricity (AC 100V), inspection cycle (1 year) Ultrasonic stirrer: RPM 420 -1480 rpm, Utrasonic output: 35W Use distilled water Wearing goggles, safety gloves Stirrer waterbath 1 time usage 45 minutes, electricity (AC 220V), inspection cycle (1 year) Stirrer waterbath: rotation speed 60-1000rpm, Temp range: 5℃-99℃ Use distilled water Safety gloves Sonicator
30 minutes of usage, electricity (AC 220V), inspection cycle (1 year) Sonicator: Ultrasonic output: 40W Use distilled water Safety gloves Packing Coating machine
1 time usage 5 minutes, electricity (AC 220V), inspection cycle (1 year) - - Safety gloves Cutting plotter
10 minutes per use, electricity (AC 220V), inspection cycle (1 year) - - Safety gloves Vacuum packing machine 1 time usage 2 minutes, electricity (220V), inspection cycle (1 year) - - Safety gloves

2. Storage stability before using TTI

After 100 TTIs according to the present invention were frozen and stored (-35° C.), 50 after 1 month and 50 after 2 months were taken out and activated. After activation, the color change and shelf life were examined to compare the incidence of defective products with 50 control groups (used immediately after production).

in normal operation malfunction Defective product incidence rate Immediately after production 50 0 0% Used after 1 month of storage 49 pcs One 2% Used after 2 months of storage 49 pcs One 2%

As shown in Table 5, the TTI according to the present invention was found to have a very low incidence of defective products at 2 months after storage, indicating excellent storage stability before use.

3. Whether the TTI is operating normally (whether it is normally activated)

Packed in 100 units of a vacuum nitrogen-packed printed TTI pack and packaged at -35℃. According to the storage period, when the pack packed with vacuum nitrogen was opened, the accuracy was confirmed by confirming that the stored color of the printed TTI was the same as the color stored by printing for the first time (Table 6).

normal Defective product incidence rate 1 month storage 99% One% 2 months storage 95% 5%

As shown in Table 6, the TTI according to the present invention shows that the incidence of defective products is very low at 2 months after storage, and thus, activation occurs stably even when stored for 2 months.

4. TTI endpoint standardization

Printed TTI is manufactured in large quantities, stored at -35℃, and the stored TTI is taken out after 1 month. Through the period of use, standardization and quality control were confirmed.

10 to 12, a graph comparing the time taken to reach the end point and the color of the printed TTI when it is reached is disclosed. After 3 months, it was confirmed that 3 out of 50 TTIs (approximately 6%) had errors in TTIs. And when it was about 3 months, it was confirmed that an error of 10% occurred in the speed of reaching the end point.

In addition, the amount of L-ascorbic 1.75g and L-cysteine 0.35g can be used for 0.2g of Methylene blue, but when more antioxidants are added, the end point becomes unstable (Table 7: TTI according to antioxidant content) Shelf life; Table 8: Activation energy of TTI according to antioxidant content ( E a)).

Antioxidants
(Ascorbic acid (AA), L-cysteine (Cys)) (a)
(ΔE 30.17) (b)
(ΔE 29.32) (c)
(ΔE 29.17) 5℃ 60hr 96hr 98hr 10℃ 50hr 76hr 78hr 25℃ 21hr 38hr 53hr 31℃ 18hr 21hr 26hr

Antioxidants
(Ascorbic acid (AA), L-cysteine (Cys)) Ea (kJ/mol) R ² (crystal coefficient) AA 1.0 Cys 0.2 31.3523 0.9888 AA 1.5 Cys 0.3 36.0794 0.991 AA 1.75 Cys 0.35 39.4299 0.9734

The errors and actions to solve them are summarized in the table below (Tables 9 and 10).

Raw material error measure Methylene blue When manufacturing ink at a rate of 0.1 g, end-point is unclear When manufacturing ink, the content of methylene blue is doubled to 0.2g. ascorbic acid Ascorbic acid content is higher than methylene blue content, end-point instability Stabilize end-point by reducing the content of ascorbic acid cysteine - - glycerol Ea value of printed TTI when printing glycerol content at 1% during ink production is considerably low, about 40 Ea value of printed TTI increased to 60 by manufacturing glycerol content to 5% Distilled water - -

fair error measure Double coating film When PE film is used, Ea value has high oxygen permeability Adjust oxygen permeability using PET film 0.075mm

5. Quality Management

The color change rate according to the temperature of the printed TTI and the activation energy (Ea) value obtained according to the Arrhenius equation were collected and compared with the quality control method and applicable food group data, and the results are shown in FIGS. 13 to 16. .

13 and 14, the graph of TTI according to activation energy and temperature shows that the lower the temperature, the longer it takes to reach a certain activation energy, and the lower the temperature, the slower the color change rate. , The activation energy of TTI according to the present invention was found to be 51.45 KJ/mol.

And, as described in Figs. 15 and 16, the food group similar to the expiration date and activation energy value of the printed TTI was found to be meat (Fig. 15), and it was confirmed that the expiration date was also most similar (Fig. 16). ).

In order to improve the performance of the printed TTI according to the present invention, the concentration of glycerol can be adjusted (Ea control), and the shelf life can be controlled by controlling the amount of antioxidant. However, if the manufacturing method disclosed in the present invention is not followed, the color change of the printed TTI may not be constant.

7. Evaluation of adhesion of printed TTI

For the evaluation of adhesion, a texture analyzer was used by adding an adhesive that can be used to attach the TTI. Bond, sticker adhesive, double-sided tape, and silicone were used for the tensile force test. The same paper was used to confirm the adhesion, and the size of the used paper was fixed to 5 cm in width and 7 cm in length to test (Table 11, FIGS. 17 to 20).

Adhesion Sticker Bond silicon Double-sided tape Force(g) 987.4 377.7 1493.2 1487.1

As shown in Table 11 and FIGS. 17 to 20, it was found that silicone and double-sided tape are the most resistant to adhesion. However, it may be a double-sided tape or a sticker in order to manufacture it so that it can be attached quickly and easily with the goal of mass production of TTI (Silicone takes a long time to dry after attachment).

8. TTI User Manual

Looking at the entire process for the commercialization of TTI, management including purchasing and sales at the raw material, process, and product levels must be managed. In the second process, product specifications and usage manuals were constructed as follows for the range of products and sales (FIG. 9).

After printing the printed TTI in a nitrogen vacuum, store it at -37℃, and when it needs to be used, take it out in the following steps. When the vacuum nitrogen package is opened, it is activated because contact with oxygen occurs. After attaching one printed TTI to the packaging of the desired food, it can be stored and used as food at 1℃ or 10℃. In addition, the freshness of the food can be determined by observing the color change of the TTI. The more the food is exposed to high temperatures, the more blue it may be, and if stored at low temperatures, it may turn white. Table 12 below specifically describes the SOP (standard operating procedure).

step work Purchasing process The quantity that can be manufactured on the 1st is about 1000 pieces, and it can be stored in nitrogen vacuum packaging as low as possible at -35℃. The biggest advantage of the printable TTI is that it can be appropriately adjusted according to the size, quantity, and print shape that the buyer wants, so when custom-made, a new silkscreen frame is created and printed. For this reason, determine the desired shape and size, send the picture file, and when the printable TTI is manufactured, store it at a low temperature by packing it with nitrogen vacuum to keep the quality of the printable TTI as good as possible. Then, the packs packed with nitrogen vacuum are sold again in a rigid packaging such as a box. Shipping after purchase Purchased printed TTIs are delivered in boxes in double packaging. The lower the storage temperature is, the better. If it is stacked and transported in a box, it can be transported in large quantities. Storage after transportation The storage is more stable when stored at low temperatures, so it may be refrigerated or frozen. Even after refrigeration or freezing, there is no problem because the adhesion of the printed TTI itself is still large. Attached to food packaging
Activation After removing and tearing the printed TTI packaging according to the number of products to be attached, it is like a sticker. In addition, since the activation of the printed TTI starts from the moment of opening the wrapping paper packed with vacuum nitrogen, the product must be refrigerated after attachment. TTI monitoring When first peeled from the packaging, almost nothing is visible because the printed TTI itself is transparent. However, as time goes by, the color changes to dark blue, almost matching the final color of the border. Once it turns blue, it does not return to white, so you can safely eat products that have not turned blue. TTI abolition process After tearing the wrapping paper, unused printed TTIs or used printed TTIs that have turned blue after use can all be treated the same as regular waste.

9. DTI composition composition diversification

An ink composition for TTI was prepared using the same manufacturing method as described in the Examples, except that the antioxidant and the sulfhydryl compound were combined as shown in the following table and the contents were varied. Table 13

NO. Antioxidant content Sulfurhydryl compound content One Ascorbic acid Sodium sulfite 2 Beta-carotene Sodium ascorbate 3 Butylhydroxyanisole (BHA) Methionine 4 Butylhydroxytoluene (BHT) Cysteine 5 Tert-butyl hydroquinone (TBHG) Homocysteine 6 Propyl gallate (PG) S-adenosylmethionine 7 Tocopherol Acetylcysteine 8 Beta-carotene Oxidation type glutathione 9 Ascorbic acid Reduced glutathione 10 Butylhydroxytoluene (BHT) S-acetyl-glutathione

By preparing the ink composition for TTI in a combination of 1 to 10, evaluation of storage stability, activation stability, and the like before use was performed as described above.

Claims (11)

An ink composition for an air activated printable time-temperature history indicator comprising an oxidation-reduction dye, a heat conducting fluid, an antioxidant, a sulfhydryl compound, and a solvent.
The method according to claim 1, wherein the oxidation-reduction dye is methylene green, methylene blue, luminol, nitro-fluorenone derivatives, azine, osmium phenanthrolinedione, catechol-pendant terpyridine, toluene blue, cresyl blue, nile blue, Neutral red, phenazine derivative, thionine, azure A, azure B, azure C, toluidine blue O, acetophenone, metallophthalocyanine, nile blue A, modified transition metal ligand, 1,10-phenanthroline-5, 6-dione, 1,10-phenanthroline-5,6-diol, [Re(Pen-dione)(CO)3Cl], [Re(Pen-dione)3](PF6)2, poly(metallophthalocyanine ), poly(thionine), quinone, diimine, diaminobenzene, diaminopyridine, phenosapronin, phenothiazine, phenoxazine, toluidine blue, brilliant cresyl blue, 3,4-dihydroxybenzaldehyde, Sodium 2,6-dibromophenol-indophenol, sodium o-cresol indophenol, indigotetrasulfonic acid, indigotrisulfonic acid, indigo carmine, indigomonosulfonic acid, safranin T, 2,2'- Bipyridine (Ru complex), 2,2'-bipyridine (Fe complex), nitrophenanthroline (Fe complex), N-phenylanthranylic acid, 1,10-phenanthroline (Fe complex), N-e Toxoxylysodine, 5,6-dimethylphenanthroline (Fe complex), o-dianicidine, sodium diphenylamine sulfonate, diphenylbenzidine, difetylamine, viologen, poly(acrylic acid), poly(azuric) I), poly(nyle blue A), poly(methylene green), poly(methylene blue), polyaniline, polypyridine, polypyrrole, polythiophene, poly(thieno[3,4-b]thiophene), poly( 3-hexylthiophene), poly(3,4-ethylenedioxypyrrole), poly(isothianaphthene), poly(3,4-ethylenedioxythiophene), poly(difluoroacetylene), poly(4 -Dicyanomethylene-4H-cyclopenta[2,1-b;3,4-b']dithiophene), poly(3-(4-fluorophenyl)thiophene) and poly(neutral red) An ink composition for an air activated printable time-temperature history indicator, which is at least one selected from
The method according to claim 1, wherein the heat-conducting fluid is glycerol (glycerol), triethanolamine (triethanolamine), ethylenediaminetetraacetic acid (ethylenediaminetetraacetic acid, EDTA), glycine (glycine), L-tyrosine (L-tyrosine), D-fructose (D-fructose), D-galactose (D-galactose) and at least one selected from the group consisting of sodium citrate (sodium citrate), air activated printing time-temperature hysteresis ink composition.
The method according to claim 1, The antioxidant is ascorbic acid (ascorbic acid), tocopherol (tocopherol), beta-carotene (β-carotene), butyl hydroxyanisole (BHA), butyl hydroxy toluene (BHT), Tert- butyl At least one selected from the group consisting of hydroquinone (TBHG) and propyl gallate (PG), an air-activated printable time-temperature hysteresis ink composition.
The method according to claim 4, wherein the sulfhydryl compound is at least one selected from the group consisting of methionine, cysteamine, cysteine, homocysteine, S-adenosylmethionine, acetylcysteine, reduced or oxidized glutathione and S-acetyl-glutathione. Ink composition for phosphorus, air activated printable time-temperature history indicators.
The method according to claim 1, The solvent is at least one selected from the group consisting of distilled water, methanol, ethanol and acetone, air activated printing time-temperature ink composition for time history indicators.
Forming a printing layer by printing the ink composition of claim 1 on a support; And drying the printing layer.
The method of claim 7, wherein the printing is performed by a silkscreen printing method using a silkscreen of 200 to 350 mesh, an air activated printing time-temperature history indicator.
The method according to claim 7, Forming a film layer on the dried print layer; And forming a coating layer on the film layer.
The method of claim 7, wherein the film layer is at least one selected from the group consisting of PE, PET, PVC, and OPP.
An air-activated printable time-temperature history indicator manufactured by the method of claim 7.

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