Photochromic ink

Abstract

The invention discloses a photochromic ink. The photochromic ink is prepared from a photochromic dye and an ink, the photochromic dye is selected from a red photochromic dye, a green photochromic dye and a blue photochromic dye; the photochromic ink disclosed by the invention has the advantages of simple preparation process, high drying speed and good adhesive force, various color changes are realized at the same time, and multiple back-and-forth irradiation can be stably carried out in the whole process. In addition, the ink also has certain waterproof performance, can be printed on different substrates, and expands the application potential of the ink.

Description

Technical Field

[0001] The present invention belongs to the technical field of ink preparation, and specifically relates to a photochromic ink. Background Art

[0002] With the continuous progress of technology, single anti-counterfeiting technologies are becoming increasingly easy to counterfeit, and the phenomenon of counterfeiting and shoddy products persists despite repeated bans. Consumers face difficulties in distinguishing the authenticity of products, seriously affecting the genuine product market. Therefore, anti-counterfeiting technology is crucial for the survival and development of enterprises and their products. Among many anti-counterfeiting technologies, flexible printing anti-counterfeiting is widely used due to its advantages such as simple implementation, convenient inspection, and good concealment. The design and development of photochromic inks are particularly crucial, which can undergo reversible color changes under light conditions to achieve visible or invisible markings. Compared with thermochromic inks (CN103113785A), photochromic inks are made of special photosensitive materials and can exhibit unique color changes under different light conditions, with higher security and non-replicability. This makes photochromic inks have significant advantages in the anti-counterfeiting field and are widely applicable to labels, packaging, and other anti-counterfeiting printed products. However, current photochromic inks usually have only two color change states, limiting their application in higher-precision anti-counterfeiting devices. Therefore, continuing to develop photochromic inks that can achieve multi-color changes will significantly improve their anti-counterfeiting security level and meet more stringent market demands.

[0003] Traditional photochromic inks (CN103319936A) have the defects of single color change and easy imitation, resulting in an urgent need to improve their anti-counterfeiting performance. Thermochromic inks are relatively complex in preparation process and have a slow drying speed of the ink. Summary of the Invention

[0004] The purpose of the present invention is to provide a photochromic ink.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect of the present invention, there is provided a photochromic ink, which is made of the following components in parts by weight:

[0007] Photochromic dye 0.5 - 5 parts, and the ink is 95 - 99.5 parts;

[0008] The concentration of the ink is 0.5 g / ml - 1.0 g / ml;

[0009] The photochromic dye is selected from red photochromic dye, green photochromic dye, and blue photochromic dye;

[0010] The structure of the red photochromic dye is as follows:

[0011] ;

[0012] The structure of the green photochromic dye is as follows:

[0013] ;

[0014] The structure of the blue photochromic dye is as follows:

[0015] .

[0016] The photochromic ink is made of the following components by weight:

[0017] 0.99 parts of photochromic dye and 99.01 parts of ink.

[0018] The photochromic ink is made of the following components by weight:

[0019] 1.96 parts of photochromic dye and 98.04 parts of ink.

[0020] The concentration of the ink is 0.6, 0.9 g / ml.

[0021] The photochromic ink of the present invention is applicable to a variety of materials, including but not limited to glass, plastic substrates, flexible substrates, paper materials (cardboard), fabrics, and wood materials.

[0022] The printed patterns of the photochromic ink of the present invention can be controlled by ultraviolet light, visible light, sunlight or white light LED.

[0023] The printing method of the photochromic ink of the present invention is to perform laminated printing in accordance with different ink sequences, and after printing, it is dried at a constant temperature of 25 - 50 °C for 0.5 - 3 min.

[0024] In the second aspect of the present invention, a preparation method of the photochromic ink is provided, including the following steps:

[0025] Mix the photochromic dye and the ink, then add a solvent (preferably dichloromethane) to dissolve, stir evenly, and after the solvent is completely volatilized, the photochromic ink is obtained.

[0026] The preparation method of the ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 0.5 g / ml - 1.0 g / ml.

[0027] In the third aspect of the present invention, a printed matter is provided, which is obtained by printing with the photochromic ink.

[0028] In the fourth aspect of the present invention, a printing method is provided, and the printing method uses the photochromic ink.

[0029] In the fifth aspect of the present invention, a printing system is provided, including the photochromic ink.

[0030] In the sixth aspect of the present invention, an anti-counterfeiting product (such as an anti-counterfeiting label, etc.) is provided, which is made of the photochromic ink.

[0031] The anti-counterfeiting products can all be controlled by ultraviolet light, visible light, sunlight or white light LED.

[0032] Due to the adoption of the above technical solutions, the present invention has the following advantages and beneficial effects:

[0033] The photochromic ink of the present invention has a simple preparation process and a convenient inspection technology. By combining different color-changing inks, multi-color changes can be achieved, and the color changes are obvious.

[0034] During the light regulation process of the photochromic ink of the present invention, the color change can be directly observed by the naked eye without the aid of complex instruments.

[0035] The photochromic ink of the present invention can print patterns of different sizes and shapes according to requirements and quantities, and can be applied to different materials, with high universality.

[0036] The photochromic ink of the present invention has a simple preparation process, a fast drying speed and good adhesion (can be rubbed and washed), and at the same time realizes multiple color changes. The whole process can be stably irradiated back and forth multiple times. In addition, the ink also has certain waterproof performance; it can be printed on different substrates, expanding its application potential. Description of the Drawings

[0037] Figure 1 It is a schematic diagram of the color change of the photochromic ink.

[0038] Figure 2 It is a schematic diagram of the pattern prepared in Comparative Example 1.

[0039] Figure 3 It is a schematic diagram of a pattern with multi-color changes.

[0040] Figure 4 It is a schematic diagram of the ink applied to the ISEF pattern prepared in Comparative Example 2.

[0041] Figure 5 It is a schematic diagram of a pattern with multi-color changes prepared in Example 2.

[0042] Figure 6 It is a schematic diagram of the color-changing pattern prepared in Comparative Example 3.

[0043] Figure 7 It is a schematic diagram of the ink applied to the ISEF pattern prepared in Example 3. Detailed implementation mode

[0044] To more clearly illustrate the present invention, the present invention will be further described below in conjunction with preferred embodiments. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0045] Figure 1 It is a schematic diagram of the color change of photochromic ink. Among them, 101 is 365 nm ultraviolet light, and 201 is 530 nm visible light.

[0046] The photochromic ink prepared from red photochromic dye is light red, and red is produced after irradiation with 365 nm ultraviolet light. Under the irradiation of 530 nm visible light, it can fade completely, and the whole process can be stably carried out for multiple rounds of back-and-forth irradiation.

[0047] The photochromic ink prepared from blue photochromic dye is light blue, and blue is produced after irradiation with 365 nm ultraviolet light. Under the irradiation of 530 nm visible light, it can fade completely, and the whole process can be stably carried out for multiple rounds of back-and-forth irradiation.

[0048] The photochromic ink prepared from green photochromic dye is light green, and green is produced after irradiation with 365 nm ultraviolet light. Under the irradiation of 530 nm visible light, it can fade completely, and the whole process can be stably carried out for multiple rounds of back-and-forth irradiation.

[0049] 401 is to print a pattern again on the printed pattern. During the ultraviolet light irradiation process, the color of the superimposed printed pattern changes, and it can change color again during the fading process and finally fade completely. The whole process can be stably carried out for multiple rounds of back-and-forth irradiation.

[0050] Laminated printing: First, apply red photochromic ink, and after drying at a constant temperature of 30 °C for 1 min, then apply blue photochromic ink, and finally dry at a constant temperature of 30 °C for 1 min. The change process of red - blue - blue - red - red: First, apply red photochromic ink, and the pattern appears light red. Laminated print blue photochromic ink, and the pattern appears light blue. Irradiate with 365 nm ultraviolet light, and the pattern appears blue. Irradiate with 530 nm visible light, and the pattern appears red. Finally, it fades completely, and the pattern appears light red.

[0051] Laminated printing: First, apply the green photochromic ink, and under the condition of a temperature of 30 °C, dry it at a constant temperature for 1 minute. Then, apply the blue photochromic ink, and finally, under the condition of a temperature of 30 °C, dry it at a constant temperature for 1 minute. The change process of green - blue - blue - green - green: First, use the green photochromic ink to paint, and the pattern appears light green. Laminated print the blue photochromic ink, and the pattern appears light blue. Irradiate with 365 nm ultraviolet light, and the pattern appears blue. Irradiate with 530 nm visible light, and the pattern appears green. Finally, it fades completely, and the pattern appears light green.

[0052] The preparation of the red photochromic dye used in the embodiments of the present invention refers to the patent application with the publication number CN101974002A.

[0053] The preparation of the green photochromic dye used in the embodiments of the present invention refers to the patent application with the publication number CN1765900A.

[0054] The preparation of the blue photochromic dye used in the embodiments of the present invention refers to the patent application with the publication number CN116239561A.

[0055] The structure of the red photochromic dye used in the embodiments of the present invention is as follows:

[0056] ;

[0057] The structure of the green photochromic dye used in the embodiments of the present invention is as follows:

[0058] ;

[0059] The structure of the blue photochromic dye used in the embodiments of the present invention is as follows:

[0060] .

[0061] Comparative Example 1

[0062] A preparation method of a photochromic ink includes the following steps:

[0063] Ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 0.3 g / ml.

[0064] Add 0.001 g of blue photochromic dye and 0.1 g of the ink with a concentration of 0.3 g / ml to a transparent glass bottle and mix them. Then add dichloromethane to dissolve, stir evenly at 600 rpm. After the dichloromethane completely volatilizes, obtain the blue photochromic ink.

[0065] Use of photochromic ink: 0.02 g of photochromic ink was screen-printed on a cardboard substrate, and the four letters ISEF were precisely painted. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min. The pattern was initially light blue and could not be erased. Figure 2 is a schematic diagram of the pattern prepared in Comparative Example 1. When the surface of the cardboard was irradiated with ultraviolet light (365 nm, 1 mW cm -2 ), after 2 s, it could be found that all the letters turned blue; then when irradiated with visible light (530 nm, 4 mW cm -2 ), within 5 min, the color of the picture slowly faded and finally became colorless. This process could be directly observed and tested by the naked eye, but the pattern was blurred, the edges were rough, and the color was uneven.

[0066] Example 1

[0067] A preparation method of photochromic ink includes the following steps:

[0068] Ink: Ethyl cellulose was dissolved in terpineol to obtain an ink with a concentration of 0.6 g / ml.

[0069] 0.001 g of green photochromic dye and 0.1 g of the ink with a concentration of 0.6 g / ml were added to a transparent glass bottle and mixed, and then dichloromethane was added for dissolution. After stirring evenly at 600 rpm and waiting for the dichloromethane to completely volatilize, green photochromic ink was obtained.

[0070] 0.006 g of blue photochromic dye and 0.3 g of the ink with a concentration of 0.6 g / ml were added to a transparent glass bottle and mixed, and then dichloromethane was added for dissolution. After stirring evenly at 600 rpm and waiting for the dichloromethane to completely volatilize, blue photochromic ink was obtained.

[0071] Use of photochromic ink: 0.02 g of green photochromic ink was screen-printed on a cardboard substrate, and the four letters ISEF were precisely painted. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min, and the pattern could not be erased. Through screen printing technology, 0.2 g of blue photochromic ink was precisely painted on the ISEF pattern to form a circular pattern. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min to obtain a multi-color changeable pattern, light blue. Figure 3 is a schematic diagram of the multi-color changeable pattern. The starting color was light blue. Under the action of ultraviolet light (365 nm, 1 mW cm -2 ), after 2 s, it presented as a blue circle. Under the action of visible light (530 nm, 4 mW cm -2 ), within 1 min, the color gradually changed, showing a green ISEF letter pattern. Under visible light (530 nm, 4 mW cm -2)Continue irradiation. Within 5 minutes, the color gradually fades back to the initial light blue state. The whole process can be directly observed and inspected by the naked eye. The pattern is clear and the color discrimination is obvious.

[0072] Comparative Example 2

[0073] A preparation method of a photochromic ink comprises the following steps:

[0074] Ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 1.2 g / ml.

[0075] Add 0.001 g of blue photochromic dye and 0.1 g of the ink with a concentration of 1.2 g / ml into a transparent glass bottle and mix them. Then add dichloromethane to dissolve and stir evenly at 600 rpm. After the dichloromethane completely volatilizes, blue photochromic ink is obtained.

[0076] Use of the photochromic ink: Print 0.02 g of blue photochromic ink on a cardboard substrate by screen printing, precisely brush the four letters ISEF, and dry it at a constant temperature of 30 °C for 1 minute. The initial pattern is light blue and cannot be erased. Figure 4 It is a schematic diagram of the ISEF pattern painted with the ink prepared in Comparative Example 2. When irradiating the cardboard surface with ultraviolet light (365 nm, 1 mW cm -2 ) After 2 seconds, it is found that all the letters turn blue; then when irradiating with visible light (530 nm, 4 mW cm -2 ) Within 5 minutes, the color of the picture slowly fades and finally becomes colorless. This process can be directly observed and inspected by the naked eye, but the pattern is discontinuous, the edge is rough, and the color is uneven.

[0077] Example 2

[0078] A preparation method of a photochromic ink comprises the following steps:

[0079] Ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 0.9 g / ml.

[0080] Add 0.002 g of red photochromic dye and 0.1 g of the ink with a concentration of 0.9 g / ml into a transparent glass bottle and mix them. Then add dichloromethane to dissolve and stir evenly at 600 rpm. After the dichloromethane completely volatilizes, red photochromic ink is obtained.

[0081] Add 0.002 g of blue photochromic dye and 0.1 g of the ink with a concentration of 0.9 g / ml into a transparent glass bottle and mix them. Then add dichloromethane to dissolve and stir evenly at 600 rpm. After the dichloromethane completely volatilizes, blue photochromic ink is obtained.

[0082] Use of photochromic ink: 0.02 g of red photochromic ink was screen-printed on a plastic substrate, precisely brushing the four letters ISEF. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min, and the pattern was non-erasable. Through screen-printing technology, 0.02 g of blue photochromic ink was precisely brushed on the ISEF pattern. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min to obtain a multi-color changing pattern, light red. Figure 5 It is a schematic diagram of the multi-color changing pattern prepared in Example 2. The starting color is light red. Under ultraviolet light (365 nm, 1 mW cm -2 ), after 2 s, it presents as a blue ISEF letter pattern. Under visible light (530 nm, 4 mW cm -2 ), within 1 min, the color gradually changes to show a red ISEF letter pattern. When irradiated continuously with visible light (530 nm, 4 mW cm -2 ), within 5 min, the color gradually fades back to the initial light red state. The whole process can be directly observed and inspected by the naked eye, and the pattern is clear and the color resolution is obvious.

[0083] Example 3

[0084] A preparation method of photochromic ink comprises the following steps:

[0085] Ink: Ethyl cellulose was dissolved in terpineol to obtain an ink with a concentration of 0.9 g / ml.

[0086] 0.002 g of red photochromic dye and 0.1 g of the ink with a concentration of 0.9 g / ml were added to a transparent glass bottle and mixed, and then dichloromethane was added for dissolution. It was stirred evenly at 600 rpm. After the dichloromethane was completely volatilized, red photochromic ink was obtained.

[0087] 0.002 g of blue photochromic dye and 0.1 g of the ink with a concentration of 0.9 g / ml were added to a transparent glass bottle and mixed, and then dichloromethane was added for dissolution. It was stirred evenly at 600 rpm. After the dichloromethane was completely volatilized, blue photochromic ink was obtained.

[0088] Use of photochromic ink: 0.02 g of blue photochromic ink was screen-printed on a plastic substrate, precisely brushing the four letters ISEF. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min; the initial pattern was light blue and non-erasable. Through screen-printing technology, 0.02 g of red photochromic ink was precisely brushed on the ISEF pattern. Under the condition of a temperature of 30 °C, it was dried at a constant temperature for 1 min to obtain a color-changing pattern. Figure 6It is a schematic diagram of the color-changing pattern prepared in Comparative Example 3. The starting color is light red. Under ultraviolet light (365 nm, 1 mW cm -2 ), after 2 s, it presents as a red ISEF letter pattern. Under visible light (530 nm, 4 mW cm -2 ), within 5 min, the color gradually fades back to the initial light red state. The whole process can be directly observed and inspected by the naked eye. The pattern is clear and there is no multiple color change.

[0089] Example 4

[0090] A preparation method of a photochromic ink comprises the following steps:

[0091] Ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 0.9 g / ml.

[0092] Add 0.002 g of red photochromic dye and 0.1 g of the ink with a concentration of 0.9 g / ml into a transparent glass bottle and mix them. Then add dichloromethane to dissolve and stir evenly at 600 rpm. After the dichloromethane completely volatilizes, obtain red photochromic ink.

[0093] Use of the photochromic ink: Screen-print 0.02 g of red photochromic ink on the fabric, precisely brush the four letters ISEF, and dry it at a constant temperature of 30 °C for 1 min. The initial pattern is light red and cannot be erased. Figure 7 It is a schematic diagram of the ISEF pattern brushed with the ink prepared in Example 3. When irradiating the fabric surface with ultraviolet light (365 nm, 1 mW cm -2 ), after 2 s, a red ISEF letter pattern appears; then when irradiating with visible light (530 nm, 4 mW cm -2 ), within 5 min, the color of the picture slowly fades, and finally reaches light red. This process can be directly observed and inspected by the naked eye. The pattern is clear and the color resolution is obvious. After being washed with water, the pattern is still clear and can undergo photochromism.

[0094] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art of this patent, without departing from the scope of the technical solution of the present invention, can make some changes or modifications using the above-mentioned technical content as equivalent change equivalent embodiments. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the present invention.

Claims

1. A photochromic ink, characterized in that, It is made of the following components in parts by weight: 0.5 to 5 parts of photochromic dye and 95 to 99.5 parts of ink; The concentration of the ink is 0.5 g / ml to 1.0 g / ml; The photochromic dye is selected from red photochromic dye, green photochromic dye, and blue photochromic dye; The structure of the red photochromic dye is shown as follows: ； The structure of the green photochromic dye is shown as follows: ； The structure of the blue photochromic dye is shown as follows: 。 2. The photochromic ink according to claim 1, characterized in that, The photochromic ink is made of the following components in parts by weight: 0.99 part of photochromic dye and 99.01 parts of ink.

3. The photochromic ink according to claim 1, characterized in that, The photochromic ink is made of the following components in parts by weight: 1.96 parts of photochromic dye and 98.04 parts of ink.

4. The photochromic ink according to claim 1, characterized in that, The concentration of the ink is 0.6, 0.9 g / ml.

5. A method for preparing the photochromic ink according to any one of claims 1 to 4, characterized in that, It includes the following steps: Mix the photochromic dye and the ink, then add a solvent to dissolve and stir evenly. After the solvent completely volatilizes, the photochromic ink is obtained.

6. The preparation method of the photochromic ink according to claim 5, characterized in that, The preparation method of the ink: Dissolve ethyl cellulose in terpineol to obtain an ink with a concentration of 0.5 g / ml to 1.0 g / ml.

7. A printed matter, characterized in that, It is obtained by printing with the photochromic ink described in any one of claims 1 to 4.

8. A printing method, characterized in that, The printing method uses the photochromic ink described in any one of claims 1 to 4.

9. A printing system, characterized in that, It includes the photochromic ink described in any one of claims 1 to 4.

10. An anti-counterfeiting product, characterized in that, It is made of the photochromic ink described in any one of claims 1 to 4.

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