WO2019165797A1

WO2019165797A1 - Reverse thermochromic overprinted dual-layer displayed two-dimensional code and preparation method therefor

Info

Publication number: WO2019165797A1
Application number: PCT/CN2018/113232
Authority: WO
Inventors: 田君飞; 徐军飞; 曹榕; 陈广学; 李东建; 唐华
Original assignee: 华南理工大学
Priority date: 2018-02-28
Filing date: 2018-10-31
Publication date: 2019-09-06
Also published as: CN108460444A; CN108460444B

Abstract

Disclosed are a reverse thermochromic overprinted dual-layer displayed two-dimensional code and a preparation method therefor. The reverse thermochromic overprinted dual-layer displayed two-dimensional code successively comprises a backing layer (1), a fixed color developing layer (2) and a reverse thermochromic layer (3) from bottom to top, wherein the color of the fixed color developing layer (2) does not change with the change of an external environment; and the reverse thermochromic layer (3) is a colorless transparent layer at normal temperature, becomes a colored layer after being heated, and then becomes a colorless transparent layer after being cooled to room temperature. According to the preparation method of the present invention, a two-dimensional code is printed on the backing layer with a conventional UV ink, and then a reversible reverse thermochromic ink which is colorless and transparent at normal temperature and changes color by heating is used to overprint a two-dimensional code on the two-dimensional code printed with the conventional UV ink, so that the reverse thermochromic overprinted dual-layer displayed two-dimensional code is prepared and obtained. The preparation method is easy to operate and is cost-effective.

Description

Reverse thermochromic overprint double-layer display two-dimensional code and preparation method thereof

技术领域Technical field

The invention relates to the technical field of two-dimensional code display and preparation, in particular to a reverse thermochromic overprint double-layer display two-dimensional code and a preparation method thereof.

背景技术Background technique

QR code anti-counterfeiting is a kind of anti-counterfeiting technology, Japan uses QR The countries with the most QR codes, followed by the United States, South Korea, etc., the two-dimensional codes are more and more recognized and accepted by the public. A large number of domestic anti-counterfeiting companies have begun to systematically research and develop QR codes, and the QR code anti-counterfeiting is also compliant. Market demand came into being and quickly became a market Anti-counterfeiting traceability new trend, QR The QR code has gradually become the mainstream development trend. The two-dimensional code anti-counterfeiting system can generate the encrypted two-dimensional code product information corresponding to the product one by one, and print or label the two-dimensional code on the product packaging, and the user only needs to perform decoding test through the designated two-dimensional code anti-counterfeiting system or mobile phone software. , can not only know a series of genuine safety information of the product, so as to achieve the role of rest assured purchase and supervision of counterfeiting. QR code anti-counterfeiting using two-dimensional code Encryption technology The two-dimensional code is printed or labelled on the product packaging, and the user can verify the authenticity of the product and obtain detailed information by simply decoding and verifying through the designated two-dimensional code anti-counterfeiting system or mobile phone software. The QR code can store a wealth of product information, and it is not easy to be copied and stolen by encryption. The product information is officially released from the enterprise, and the query channel is regular and professional, which realizes the high efficiency of product information anti-counterfeiting.

QR code The anti-counterfeiting system is a two-dimensional code electronic application service system developed based on market application requirements such as product anti-counterfeiting and verification. We will design mature solutions for each link of product delivery and distribution to distribution channels, and use QR code recognition, mobile communication and other technologies to load the sales area, authenticity and other information. At the same time, through the technical means of mobile communication, by verifying the circulation of product code monitoring products, it avoids the occurrence of counterfeit goods and other phenomena, facilitates enterprise management, improves consumer satisfaction and establishes a good brand image. The QR code of the product information generated by the QR code anti-counterfeiting system can be printed or labelled on the product packaging. After the consumer purchases, it can be decoded through the official website or the designated mobile phone software to verify the authenticity of the product and obtain detailed information. . The QR code can store a wealth of product information, and the information source is reliable and authoritative, achieving high efficiency of product information anti-counterfeiting. For a long time, counterfeit and shoddy goods have jeopardized the vital interests of enterprises and consumers, seriously affecting the country's economic development. In order to protect the interests of enterprises and consumers and ensure the healthy development of the market economy, the state and enterprises spend a lot of manpower and financial resources for anti-counterfeiting and anti-counterfeiting every year. However, subject to anti-counterfeiting technology and anti-counterfeiting methods, ordinary consumers lack factors such as anti-counterfeiting tools, and the anti-counterfeiting effect is not satisfactory. The QR code has multiple anti-counterfeiting features, which can be anti-counterfeiting by password anti-counterfeiting, software encryption, etc., so it has strong security and anti-counterfeiting performance.

China has entered a critical stage of vital importance for economic and social development. To this end, the anti-counterfeiting industry must further implement the scientific development concept. This requires us to accurately grasp the pulse of economic and social development and the trend of industry development, and actively create a good industry. The interactive atmosphere advocates and promotes the integrity and self-discipline of the industry, increases the intensity of publicity, and allows more understanding, care and support for the anti-counterfeiting industry.

The two-dimensional code provides a lot of convenience in the information storage and recognition of life, but the two-dimensional code is also copied. The false information of some two-dimensional codes brings great economic loss to the consumers. Therefore, in the two-dimensional code The field of anti-counterfeiting should be equally valued. S.Han (2012, Adv Mater The others use a photosensitive resin and a fluorescent dye-modified acrylate to form a microscopic polymer QR code, which is placed in a drug for anti-counterfeiting detection of drug information. Jue Hou (2016,Chem Asian J ) studied a four-dimensional two-dimensional code. By changing the display of different regions of a two-dimensional code, only one layer of information can actually be displayed. Patent CN104239925A A method for printing and identifying invisible encrypted two-dimensional code is published. The patent combines the double anti-counterfeiting characteristics of the encrypted two-dimensional code and the recessive ink, and the professional reading device can be used to identify the anti-counterfeiting information. After using this technology, the two-dimensional code is encrypted. The information needs to be displayed under ultraviolet or infrared light, and then the professional reading device is used to read the encrypted information in the two-dimensional code. Although the two-dimensional code realized by the method increases the anti-counterfeiting property, it can only display a single The information and identification of the two-dimensional code requires a professional reading device that is not conducive to popularization. patent CN103679241A A method and a method for generating an invisible two-dimensional code anti-counterfeit label are disclosed. The patent determines whether encryption is needed by inputting anti-counterfeiting information. If yes, the next step is performed. Otherwise, the next step is skipped and the following steps are performed. Encrypting the anti-counterfeiting information to obtain the encrypted information, encoding the anti-counterfeiting information or the encrypted information to generate an invisible two-dimensional code pattern, dividing the invisible two-dimensional code pattern into a positioning code pattern and an information code pattern, and generating a corresponding two-layer film. The positioning code pattern and the information code pattern are separately printed to a specified position of the carrier using at least two different wavelength-sensitive inks or toners, the two-dimensional code improving the encryption, but only displaying a single information. patent CN104850883A A method for generating a multi-gray invisible two-dimensional code is disclosed. The method adopts an information symbol having several levels of gray scales, and does not need to adopt the frame positioning of the three corners of the prior art, so that the two-dimensional code can carry More code-loaded information, however, multi-gray modification of the two-dimensional code can increase the information load of the two-dimensional code, and cannot display the two-dimensional code for the information. patent CN105419487A An irreversible invisible two-dimensional code is published. The irreversible invisible two-dimensional code is invisible or partially invisible under normal conditions, and only appears under certain conditions, and the two-dimensional code is irreversible and specific. After color development under conditions, and can not be restored, this two-dimensional code design can only display one layer of information at a time. patent CN106128294A An anti-counterfeiting mark with a two-dimensional code of variable invisible information and a preparation method thereof are disclosed. The two-dimensional code is composed of an oil varnish layer, a variable data layer, a variable stealth information layer, a first water varnish layer, and an outer layer. Surface printing layer, paper layer, plasticizing layer, dielectric layer, second aqueous varnish layer, variable verification data layer, white ink layer, glue layer, silicone oil layer, bottom paper layer and black ink layer are combined to realize invisible single information Security.

Patent CN107169547A A two-layer printed photo response two-dimensional code is disclosed, which comprises a backing layer, a first layer two-dimensional code, and a second layer two-dimensional code. This patent first proposed the concept of double-stacked two-dimensional code dual display, using UV Light achieves the realization of two-layer information. In order to make it more convenient for mass application, we can realize the realization of double-layer information through thermal change. Only one lighter can read the two layers of information of this patent two-dimensional code. However, in combination with the above prior art, it can be found that the existing two-dimensional code improvement technology focuses on the encryption of single-layer information of the two-dimensional code, the increase of the load information of the two-dimensional code, and the single-layer stealth anti-counterfeiting of the two-dimensional code. That is to say, the current two-dimensional code can only display one kind of information on the anti-counterfeiting information display, and the invisible two-dimensional code is also a display process of the information from the endless, for the thermochromic double-layer information two-dimensional code information display, reaching the two-dimensional code The purpose of high-end anti-counterfeiting has not yet been discovered.

发明内容Summary of the invention

It is an object of the present invention to provide a reverse thermochromic overprinting two-layer display two-dimensional code in view of the deficiencies of the prior art. The QR code will be at room temperature Transparent, colorless, heat-discoloring, reversible reverse thermochromic ink overprinted in conventional UV On the two-dimensional code printed by ink, the hidden layer two-dimensional code is displayed by the principle of heating color, and the gray level difference between the two kinds of two-dimensional codes is set to achieve the display requirement that the information display does not interfere with each other, and the purpose of multi-information display is realized. The two-dimensional code achieves the effect of high-end anti-counterfeiting, the anti-counterfeiting effect is remarkable, and the identification is convenient .

It is also an object of the present invention to provide a method of preparing a reverse thermochromic overprinting two-layer display two-dimensional code. The preparation method uses conventional UV on the backing layer After printing the two-dimensional code of the ink, the transparent colorless, heat-discoloring reversible reverse thermochromic ink at normal temperature is used in conventional UV. The two-dimensional code is superimposed on the two-dimensional code printed by the ink to prepare a reverse thermochromic overprint double-layer display two-dimensional code, and the preparation method is simple in operation and low in cost.

The object of the present invention is achieved by the following technical solutions.

A reverse thermochromic overprinting double-layer display two-dimensional code, from bottom to top, comprising a backing layer, a fixed color developing layer and a reverse thermochromic layer in sequence;

The color of the fixed color developing layer does not change according to changes in the external environment;

The reverse thermochromic layer is a colorless transparent layer at normal temperature, and becomes a colored layer after heating, and then becomes a colorless transparent layer after cooling to room temperature.

Preferably, the material of the backing layer comprises paper or a plastic film.

Preferably, the color gradation value of the fixed color rendering layer is 9 to 90 larger than the color gradation value of the backing layer.

Preferably, the fixed color-developing layer and the reverse thermochromic layer after heating and discoloration are both colored or gray, and the color gradation value of the reverse thermochromic layer after heating and discoloration is smaller than the color ash of the fixed color-developing layer. The degree is greater than 16 degrees.

A method for preparing a reverse thermochromic overprint double layer display two-dimensional code according to any of the above, comprising the steps of:

(1) printing on the backing layer material with UV ink, and curing by UV to obtain a fixed color developing layer;

( 2 Then using a transparent reverse thermochromic ink to print on the upper surface of the obtained fixed color developing layer, heat curing, overprinting to form a reverse thermochromic layer, and obtaining the reverse thermochromic overprint double layer display two-dimensional code .

Preferably, the transparent reverse thermochromic ink comprises, by mass percentage, the following raw material components:

Reverse thermochromic microcapsules 5~80%;

Dow Corning produces 5~60% silicone rubber grade Sylgard 184A ;

Dow Corning produces 0.5 to 5% curing agent for Sylgard 184B ;

Solvent 5~25% ;

Additives 1~12%.

Further preferably, the reverse thermochromic microcapsule is composed of a microcapsule core wall coated with a microcapsule core material and has a particle diameter of 5 to 200 μm. particle.

Still more preferably, the microcapsule core wall is melamine powder and 37 wt% formaldehyde solution by mass ratio 1:4~1:8 at 75 Microfilm formed by polymerization at °C for 2 hours.

Still more preferably, the microcapsule core material is a mixture of an invisible coloring substance and a color reaction acid at a mass ratio of 1:10 to 1:20. Hot melted product at 120~150 °C.

Still further preferably, the invisible chromogenic substance comprises 2-phenylamino-3-methyl-6-dibutylaminofluoran or 3,3-di (4- Diethylamino-2-ethoxyphenyl)-4-azabenzoquinone.

Still further preferably, the color reaction acid is 4- One or more of n-octyloxyphenol, lauric acid, dodecanoic acid, tridecanoic acid, palmitic acid, gallic acid, and stearic acid.

Further preferably, the solvent Ethanol, ethyl acetate, chloroform, dichloromethane, chloroform, isopropanol, n-butanol, ethyl acetate, butyl acetate, isopropyl acetate, toluene, xylene, cyclohexanone, acetone and water More than one.

Further preferably, the auxiliary agent comprises, in parts by weight, the following components:

Defoamer 0.5~2 parts;

Thickener 1~7 parts;

Leveling agent 0.1~5 parts.

Further Preferably, the antifoaming agent is emulsified silicone oil, high alcohol fatty acid ester, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene alcohol ether, polyoxypropylene glyceryl ether and polyoxypropylene polyoxyethylene. More than one of glyceryl ethers.

Further Preferably, the leveling agent is one of a silicone oil, a polyether polyester modified organosiloxane, an alkyl modified organosiloxane, a terminal modified silicone, an acrylic resin, a urea resin, and a melamine formaldehyde resin. More than one species.

Further Preferably, the thickener is polyacrylamide, methyl cellulose, hydroxypropyl methyl cellulose, sodium carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide Modified paraffin resin Kappa resin, polyacrylic acid, polyacrylate copolymer emulsion, butadiene rubber, styrene butadiene rubber, polyurethane, modified polyurea, low molecular polyethylene wax, amino alcohol complex type titanate More than one of a olefinic resin, a chlorinated polyethylene, a bentonite, a diatomaceous earth, and a starch.

Preferably, the heat curing temperature is 60 to 85 ° C and the time is 20 to 60 minutes.

Preferably, the printing method is inkjet printing, screen printing, gravure printing, offset printing, flexographic printing, stamp printing and 3D. One or a combination of two or more in printing.

Compared with the prior art, the present invention has the following advantages and benefits:

( 1 The reverse thermochromic overprinting double-layer display two-dimensional code of the invention can meet the scanning code requirement by using a simple scanning code device including a common two-dimensional code scanner or WeChat sweeping, without adding special special equipment. Easy to use and popularized;

( 2 The reverse thermochromic overprinting double-layer display two-dimensional code of the invention can realize the display of two-dimensional code double-layer information by heating, and the display process does not interfere with each other, and the anti-counterfeiting effect is enhanced;

(3 The reverse thermochromic overprint double-layer display two-dimensional code of the invention has the advantages of simple preparation method, wide required materials, low preparation cost, industrialized production, and a high anti-counterfeiting and functionalization of the two-dimensional code. A new way of thinking and ways.

附图说明 DRAWINGS

1 is a schematic structural view of a reverse thermochromic overprint double-layer display two-dimensional code of the present invention;

2 is a schematic diagram showing the two-layer information display of the reverse thermochromic overprint double-layer display two-dimensional code of the present invention;

Figure 3 is the embodiment 5 The reverse thermochromic overprinting double-layer prepared by the two-dimensional code shows a schematic diagram showing the structure of the fixed color rendering layer two-dimensional code at normal temperature;

Figure 4 is the embodiment 5 The reverse thermochromic overprinting double layer is prepared to display a schematic diagram of the overall structure of the reverse thermochromic layered printing fixed color developing layer under heating conditions;

Figure 5 is the embodiment 6 The prepared reverse thermochromic overprinting double layer displays a schematic diagram of the overall structure of the reverse thermochromic layered printing fixed color developing layer under heating conditions.

具体实施方式 Detailed ways

The technical solutions of the present invention are further described in detail below with reference to the specific embodiments and the accompanying drawings, but the scope and embodiments of the present invention are not limited thereto.

In a specific embodiment, the schematic diagram of the reverse thermochromic overprinting double-layer display two-dimensional code of the present invention is shown in FIG. From bottom to top, the backing layer 1 , the fixed color developing layer 2 and the reverse thermochromic layer 3 are sequentially included;

The material of the backing layer 1 includes a paper or a plastic film; the color gray value of the fixed color layer 2 is larger than the color gray value of the backing layer 1 by 9 to 90. And the color of the fixed color rendering layer 2 does not change with changes in the external environment;

The reverse thermochromic layer 3 is a colorless transparent layer at normal temperature, and becomes a colored layer after heating, and then becomes a colorless transparent layer after cooling to room temperature; fixing the color developing layer 2 The reverse thermochromic layer 3 after heating and discoloration is color or gray, and the color gradation value of the reverse thermochromic layer 3 after heating and discoloration is larger than the color gradation value of the fixed color layer 2 by more than 16;

The two-layer information display schematic diagram of the reverse thermochromic overprint double-layer display two-dimensional code of the present invention is shown in FIG. 2, under normal temperature conditions, The reverse thermochromic layer 3 is a colorless transparent layer, and only the fixed color developing layer 2 is visible; when the two-dimensional code is heated, the reverse thermochromic layer 3 is changed from a colorless transparent layer to a colored layer, and the color is heated and discolored. Reverse thermalchromic layer 3 Overprint on the fixed color layer 2, visible double-layer QR code; when cooled, the reverse thermochromic layer 3 returns to colorless transparency.

In a specific embodiment, the reverse thermochromic microcapsules are prepared by the following method, and the specific steps are as follows:

(1) Take the invisible coloring substance and the color reaction acid according to the mass ratio 1:10~1:20, mix and mix evenly, at 120~150 °C The lower heating is completely melted, and the molten mixture is stirred and pulverized to obtain a microcapsule core material;

(2) mixing melamine powder with 37wt% formaldehyde solution by mass ratio 1:4~1:8, in oil bath 75 °C The reaction was magnetically stirred for 2 h, and the triethanolamine was used to adjust the system pH=8.5 to obtain a microcapsule core wall solution;

(3) Keep the prepared microcapsule core material at a temperature above 70 °C, and add 400 mL containing surfactant. In water, homogenizer is used for emulsification for 5 min, shear rate is 5000 r/min, and the temperature is maintained at 70 °C. After the emulsification, the microcapsule core wall solution is added, and the acidifier is added to control the pH to 3.5. , react at a temperature of 75 ° C and a stirring rate of 500 r / min for 1 h; after the reaction is finished, it is naturally cooled, and the pH is adjusted to 8 with a 10 wt% NaOH solution. The microcapsules coated with the thermochromic material are obtained by washing and drying, and the dried microcapsules are shear-dispersed by a high-speed shear mixer to obtain a powder of 5 to 200 μm, that is, a reverse thermochromic microcapsule.

In a specific embodiment, the transparent reverse thermochromic ink is prepared by the following method, and the specific steps are as follows:

Reverse thermochromic microcapsules 5~80%, Sylgard 184A 5~60%, curing agent by mass percentage Sylgard 184B 0.5~5%, solvent 5~25% and auxiliary agent 1~12% After mixing, mechanically stir for 0.5~1h, then let stand for 30min to get transparent Reverse thermochromic ink.

实施例 1 Example 1

Preparation of reversible reverse thermochromic microcapsules which are colorless at room temperature and heated to green. The specific steps are as follows:

(1) taking 3,3-bis(4-diethylamino-2-ethoxyphenyl)-4-azabenzoquinone and lauric acid by mass ratio 1:10, the mixture was uniformly stirred, heated completely at 120 ° C, and the molten mixture was stirred to be pulverized to obtain a microcapsule core material;

(2) Mixing melamine powder with 3.7 wt% formaldehyde solution at a mass ratio of 1:4, in an oil bath at 75 °C The reaction was magnetically stirred for 2 h, and the triethanolamine adjustment system PH=8.5 was used to obtain a microcapsule core wall solution;

(3) Keep the prepared microcapsule core material at 70 °C and add 400mL containing 1.0wt% xanthan gum. In water, homogenizer was used for emulsification for 5 min, shear rate was 5000 r/min, and the temperature was maintained at 70 °C. After the emulsification, the microcapsule core wall solution was added and 0.1 mol/L maleic acid was added to control. The pH is 3.5, and the reaction is carried out for 1 hour at a temperature of 75 ° C and a stirring rate of 500 r/min. After the reaction, it is naturally cooled, and the pH is adjusted to 8 with a 10 wt% NaOH solution. , washing, drying, obtaining a microcapsule coated with a reverse thermochromic material, and shearing and dispersing the dried microcapsules by a high-speed shear mixer to obtain a powder of 5 to 200 μm, that is, 3,3- 2 (4- Diethylamino-2-ethoxyphenyl)-4-azabenzoquinone Reverse thermochromic microcapsules.

The prepared reverse thermochromic microcapsule is a reversible reverse thermochromic microcapsule which is colorless at room temperature and heats green. The powder is colorless at room temperature, at 60 °C is green when heated, and becomes colorless after cooling, and the process is reversible.

实施例 2 Example 2

The preparation of reversible reverse thermochromic microcapsules which are colorless and heat-black at room temperature are as follows:

(1) Take 2-phenylamino-3-methyl-6-dibutylaminofluoran and stearic acid at a mass ratio of 1:10 and mix well. The mixture is completely melted by heating at 150 ° C, and the molten mixture is stirred and pulverized to obtain a microcapsule core material;

(2) Mixing melamine powder with 37wt% formaldehyde solution at a mass ratio of 1:4, in an oil bath at 75 °C The reaction was magnetically stirred for 2 h, and the triethanolamine was used to adjust the system pH=8.5 to obtain a microcapsule core wall solution;

(3) Keep the prepared microcapsule core material at 70 °C and add 400mL containing 1.0wt% xanthan gum. In water, homogenizer was used for emulsification for 5 min, shear rate was 5000 r/min, and the temperature was maintained at 80 °C. After the end of the emulsification, the microcapsule core wall solution was added and 0.1 mol/L maleic acid was added to control. The pH is 3.5, and the reaction is carried out for 1 hour at a temperature of 75 ° C and a stirring rate of 500 r/min. After the reaction, it is naturally cooled, and the pH is adjusted to 8 with a 10 wt% NaOH solution. , washing, drying, obtaining a microcapsule coated with a reverse thermochromic material, and shearing and dispersing the dried microcapsules by a high-speed shear mixer to obtain a powder of 5 to 200 μm, that is, 2-Benzyl-3-methyl-6-dibutylaminofluoran Reverse thermochromic microcapsules.

The reverse thermochromic microcapsules prepared are reversible reverse thermochromic microcapsules which are colorless, heat and black at room temperature, and the powder is colorless at normal temperature. It is black when heated at 80 °C and becomes colorless after cooling. The process is reversible.

实施例 3 Example 3

Preparation of transparent reverse thermochromic ink which is colorless at room temperature and heated to green. The specific steps are as follows:

Colorless heating to black ink at room temperature from 3,3-bis(4-diethylamino-2-ethoxyphenyl)-4-azabenzoquinone Reverse thermochromic microcapsules, auxiliaries and solvents, in terms of mass percentage, specific ingredients and formulation ratios are:

Example 1 Preparation of reverse thermochromic microcapsules 10%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 58% , polyacrylamide 5% , curing agent Sylgard 184B 3% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as A ink.

实施例 4 Example 4

Colorless heating to black ink at room temperature from 3,3-bis(4-diethylamino-2-ethoxyphenyl)-4-azabenzoquinone The composition of the reverse thermochromic microcapsules, the auxiliary agent and the solvent, the specific composition and the formulation ratio are:

Example 1 Prepared reverse thermochromic microcapsules 30%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 39% , polyacrylamide 5% , curing agent Sylgard 184B 2% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as B ink.

实施例 5 Example 5

Example 1 Preparation of reverse thermochromic microcapsules 50%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 19% , polyacrylamide 6% , curing agent Sylgard 184B 1% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as C ink.

实施例 6 Example 6

The preparation of transparent reverse thermochromic ink which is colorless, heat-blackened at room temperature, and the specific steps are as follows:

Room temperature, colorless heating, blackening ink, 2-phenylamino-3-methyl-6-dibutylaminofluoran The composition of the reverse thermochromic microcapsules, the auxiliary agent and the solvent, the specific composition and the formulation ratio are:

Example 2 Preparation of reverse thermochromic microcapsules 10%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 58% , polyacrylamide 5% , curing agent Sylgard 184B 3% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as D ink.

实施例 7 Example 7

Example 2 Preparation of reverse thermochromic microcapsules 30%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 39% , polyacrylamide 5% , curing agent Sylgard 184B 2% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as E ink.

实施例 8 Example 8

Example 2 prepared reverse thermochromic microcapsules 50%, toluene 18%, emulsified silicone oil 1%, Sylgard 184A 19% , polyacrylamide 6% , curing agent Sylgard 184B 1% and acrylic resin 5% ;

After mixing the components uniformly, mechanically stir at room temperature for 30 min, and let stand for 30 min. An ink which is colorless at room temperature and heats green is obtained, and is referred to as F ink.

实施例 9 Example 9

Reverse thermochromic overprinting double-layer display two-dimensional code preparation, the specific steps are as follows:

( 1 ) The two-dimensional code generated by the two-dimensional code generator is two-dimensional code of the fixed display layer and the two-dimensional code of the reverse thermochromic layer;

( 2 ) Then screen the yellow UV ink on the white paper with an inkjet printer to fix the two-dimensional code of the color layer, UV Curing the yellow ink layer to form a fixed color developing layer;

(3) On the two-dimensional code of the cured fixed color rendering layer, the transparent B ink is screen printed by the inkjet printer to reverse the two-dimensional code of the thermochromic layer. After heat curing at 70 ° C for 10 min, overprinting forms a reverse thermochromic layer, and the reverse thermochromic overprint double layer display two-dimensional code is obtained.

The structure diagram of the obtained reverse thermochromic overprint double-layer display two-dimensional code is shown in Fig. 3. As shown, the two-dimensional code of the transparent reverse thermochromic layer is overprinted on the yellow two-dimensional code pattern of the fixed color rendering layer, and only the two-dimensional code information of the fixed color rendering layer is displayed at normal temperature, and the color of the coloring layer is fixed. The gray value is larger than the color gray value of the white paper 10 At this time, use the mobile phone WeChat to scan the client and display the message 'SKLPPE'; then use 60 °C When the reverse thermochromic overprint double-layer display two-dimensional code is heated, the reverse thermochromic layer two-dimensional code shows green (the overall structure is shown in FIG. 4 Shown), at this time, the green two-dimensional code that becomes the reverse thermochromic layer is overprinted on the yellow two-dimensional code of the fixed color rendering layer, and the color gray value ratio of the green two-dimensional code of the reverse thermochromic layer The yellow color code of the fixed color rendering layer has a large gray value of 21 After using the mobile phone WeChat to scan the client scan, the message 'SCUT' is displayed and cooled for 1 min. The structure shown in Figure 4 is re-converted to the structure shown in Figure 3.

实施例 10 Example 10

( 1 Generating two-dimensional codes of two different kinds of information in the two-dimensional code generator, which are respectively a two-dimensional code of the fixed display layer and a two-dimensional code of the reverse thermochromic layer;

(2) Then on white paper, use inkjet printer to yellow UV Ink screen printing fixes the two-dimensional code of the color developing layer, and UV-cures the yellow ink layer to form a fixed color developing layer;

(3) On the two-dimensional code of the cured fixed color rendering layer, the transparent E ink is screen-printed by the inkjet printer to reverse the two-dimensional code of the thermochromic layer. Heat curing at 70 ° C for 10 min, overprinting to form a reverse thermochromic layer, and obtaining the reverse thermochromic overprint double-layer display two-dimensional code.

The structure of the obtained reverse thermochromic overprint double-layer display two-dimensional code is shown in Figure 3. The two-dimensional code of the transparent reverse thermochromic layer is overprinted on the yellow two-dimensional code pattern of the fixed color rendering layer, and only the two-dimensional code information of the fixed color rendering layer is displayed at normal temperature, and the color gray color of the fixed color rendering layer is fixed. The value is greater than the gray value of the white paper. At this time, use the mobile phone WeChat to scan the client scan and display the message 'SKLPPE'; then use 60 °C When the reverse thermochromic overprint double-layer display two-dimensional code is heated, the reverse thermochromic layer two-dimensional code shows black (the overall structure is shown in FIG. 5). Shown), at this time, the black two-dimensional code which becomes the reverse thermochromic layer is overprinted on the yellow two-dimensional code of the fixed color rendering layer, and the color gray value ratio of the black two-dimensional code of the reverse thermochromic layer Color gray value 72 of the yellow QR code of the fixed color layer After using the mobile phone WeChat to scan the client, the message 'SCUT' is displayed and cooled for 1 min. The structure shown in Figure 5 is re-converted to the structure shown in Figure 3.

The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and modifications may be made without departing from the spirit and scope of the invention. Simplifications should all be equivalent replacements and are included in the scope of the present invention.

Claims

A reverse thermochromic overprinting double-layer display two-dimensional code, characterized in that, from bottom to top, a backing layer (1), a fixed color developing layer (2) and a reverse thermochromic layer are sequentially included ( 3);

The color of the fixed color developing layer ( 2 ) does not change according to changes in the external environment;

The reverse thermochromic layer (3 It is a colorless transparent layer at normal temperature, and becomes a colored layer after heating, and then becomes a colorless transparent layer after cooling to room temperature.
A reverse thermochromic overprinting two-layer display two-dimensional code according to claim 1, wherein said backing layer (1) The material includes paper or a plastic film; the color gradation value of the fixed color developing layer (2) is 9 to 90 larger than the color gradation value of the backing layer (1).
A reverse thermochromic overprinting two-layer display two-dimensional code according to claim 1, wherein said fixed color developing layer (2) And the reverse thermochromic layer (3) after heating and discoloration is color or gray, and the color of the reverse thermochromic layer (3) after heating and discoloration is larger than the color of the fixed color developing layer (2) Gray value is 16 the above.
Preparation claims 1~3 A method for reversely thermochromic overprinting a two-layer display two-dimensional code according to any one of the preceding claims, comprising the steps of:

(1) printing on the backing layer material with UV ink, and curing by UV to obtain a fixed color developing layer;

( 2 Then using a transparent reverse thermochromic ink to print on the upper surface of the obtained fixed color developing layer, heat curing, overprinting to form a reverse thermochromic layer, and obtaining the reverse thermochromic overprint double layer display two-dimensional code .
According to claim 4 The preparation method is characterized in that the transparent reverse thermochromic ink comprises, by mass percentage, the following raw material components:

Reverse thermochromic microcapsules 5~80%;

Silicone rubber produced by Dow Corning under the designation Sylgard 184A 5~60%

Dow Corning produces 0.5 to 5% curing agent for Sylgard 184B ;

Solvent 5~25% ;

Additives 1~12%.
The preparation method according to claim 5, wherein the reverse thermochromic microcapsule is composed of a microcapsule core wall coated with a microcapsule core material, and has a particle diameter of 5~200μm particles; the microcapsule core wall is melamine powder and 37wt% formaldehyde solution at a mass ratio of 1:4~1:8 at 75 °C 2 a microfilm formed by an hour; the microcapsule core material is a product of invisible coloring matter and color reaction acid mixed at a mass ratio of 1:10 to 1:20, and then melted at 120 to 150 ° C; Color substances include 2-phenylamino-3-methyl-6-dibutylaminofluoran or 3,3-bis(4-diethylamino-2-ethoxyphenyl)-4-azabenzoquinone; Color reaction acid is 4- One or more of n-octyloxyphenol, lauric acid, dodecanoic acid, tridecanoic acid, palmitic acid, gallic acid, and stearic acid.
The preparation method according to claim 5, wherein the solvent Ethanol, ethyl acetate, chloroform, dichloromethane, chloroform, isopropanol, n-butanol, ethyl acetate, butyl acetate, isopropyl acetate, toluene, xylene, cyclohexanone, acetone and water More than one.
The preparation method according to claim 5, wherein the auxiliary agent comprises, in parts by weight, the following components:

Defoamer 0.5~2 parts;

Thickener 1~7 parts;

Leveling agent 0.1~5 parts;

The antifoaming agent is an emulsified silicone oil, a high carbon alcohol fatty acid ester, a polyoxyethylene polyoxypropylene pentaerythritol ether, a polyoxyethylene polyoxypropylene alcohol ether, a polyoxypropylene glyceryl ether, and a polyoxypropylene polyoxyethylene glyceryl ether. More than one;

The leveling agent is at least one of a silicone oil, a polyether polyester modified organosiloxane, an alkyl modified organosiloxane, a terminal modified silicone, an acrylic resin, a urea resin, and a melamine formaldehyde resin;

The thickener is polyacrylamide, methyl cellulose, hydroxypropyl methyl cellulose, sodium carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide, modified Paraffin resin , Kappa resin, polyacrylic acid, polyacrylate copolymer emulsion, butadiene rubber, styrene butadiene rubber, polyurethane, modified polyurea, low molecular polyethylene wax, amino alcohol complex type titanate More than one of a olefinic resin, a chlorinated polyethylene, a bentonite, a diatomaceous earth, and a starch.
The preparation method according to claim 4, wherein the heat curing temperature is 60 to 85 ° C and the time is 20 to 60 minutes. .
The preparation method according to claim 4, wherein the printing method is It is a combination of one or a combination of inkjet printing, screen printing, gravure printing, offset printing, flexographic printing, stamp printing, and 3D printing.