Preparation method of novel anti-counterfeiting direct plating paper

Abstract

The invention relates to a preparation method of novel anti-counterfeiting directly-plated paper, belongs to the technical field of packaging materials, and is realized by mainly depending on the interaction of a prime coating and a printing coating. According to the key point of the technical scheme, the coating comprises the following components in parts by weight: a primer coating comprises the following components in percentage by weight: 20-22% of epoxy acrylic resin; 28 to 30% of TPGDA (Thermoplastic Glycol 20%-21% of TMPTA (trimethylolpropane 28.5%-29.5% of HDDA (High Density And 0.5 to 1% of BYK333. The printing coating comprises the following components in percentage by weight: 20-24% of pure acrylic resin; 5% of epoxy acrylic acid; 35.8% to 39.8% of TPGDA (Thermoplastic 20%-22% of TMPTA (Trimethoprim Poly 13 to 15% of HDDA (Hexamethylene Diamine Diamine And 0.2%-0.5% of BYK333. The invention aims to provide the coating for prime coat and the coating for printing, which are used for producing a high-quality positioning anti-counterfeiting product, a high-brightness effect and a matte effect of a mirror surface are formed on the same printed matter through a cohesion reaction between the prime coat layer and the printing layer, high contrast of local images and texts is visually realized, and the anti-counterfeiting effect of the printed matter is improved. And the three-dimensional convex feeling and the cold ironing effect are achieved at the same time, the double requirements for counterfeiting prevention and attractiveness are met, and the requirements of the novel high-end packaging industry and the decorative material market are met.

Description

TECHNICAL FIELD

[0001] The present application relates to a preparation method of a new type of anti-fake straight plating paper, belonging to the technical field of packaging materials. BACKGROUND

[0002] With the vigorous development of the national economy and the vigorous rise of the printing and packaging industry, the requirements for the appearance of printed products are becoming higher and higher. In the post-printing processing of printed products, the three-dimensional cold stamping process is very popular due to its amazing surface finishing effect. Cold stamping process is a special printing process technology applied to paper, textiles, plastics and other materials to create unique patterns and effects. However, despite its unique advantages, the three-dimensional cold stamping process also has some challenges: first, in terms of cost, compared to traditional flat printing processes, three-dimensional cold stamping processes require more specialized equipment and high-quality materials such as films, resulting in higher costs. Especially in mass production or when complex three-dimensional effects are required, the cost will be even more significant. Second, in terms of technical requirements, three-dimensional cold stamping processes require high levels of professional skills and experience to operate and control. From design to processing, every link requires precise operation and skilled techniques to ensure the best results. In addition, the start-up speed is also a concern. Cold stamping process requires the use of special cold stamping glue or cold stamping film, which usually needs a long time to preheat, melt or reach the optimal working temperature. This process may take some time to ensure that the cold stamping material can perfectly adhere and solidify on the paper or other materials. At the same time, the cold stamping equipment and machines also need to be adjusted and calibrated to ensure uniform coating and tight compression of the cold stamping glue or film.

[0003] In the existing process, UV transfer printing technology is a technology that uses ultraviolet curing technology to quickly achieve the effect of hot stamping. The transfer printing process can be achieved without heating. The principle of this technology is to use a UV flatbed digital printer to spray white ink, varnish and other layers on a crystal film containing adhesive. The ink is quickly cured under UV light, forming a solid pattern layer, then a transfer film is applied, and finally the pattern is transferred to the product surface using the transfer film. The implementation of this technology requires the use of UV ink and thin film substrates. The production process is accompanied by a pungent odor, and the thin film substrate used is a disposable material that cannot be recycled or quickly degraded, and has no environmental advantages. In addition, it can only be used for small areas of text and graphics, and the pattern is transferred from the film to the surface of the packaging box, tea can, ceramic, metal and other materials. SUMMARY

[0004] The present application aims to provide a preparation method of a new type of anti-fake straight plating paper, which forms mirror high light and matte effects on the same printed product through the interaction of the primer layer and the printing layer. The components in the primer layer and the printing layer formula are scientifically matched to ensure the uniformity and three-dimensional effect of the printing layer.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows: A novel method for preparing anti-counterfeiting direct-coating paper, characterized by the following steps: S1, Coating A primer coating is applied to the paper substrate surface. The primer coating formulation comprises the following components by weight percentage: 20-22% epoxy acrylic resin, 28-30% TPGDA, 20-21% TMPTA, 28.5-29.5% HDDA, and 0.5-1% BYK333. S2, Printing A printing layer is applied to the surface of the base layer. The coating formulation of the printing layer comprises the following components by weight percentage: 20-24% pure acrylic resin, 5% epoxy acrylic acid, 35.8-39.8% TPGDA, 20-22% TMPTA, 13-15% HDDA, and 0.2-0.5% BYK333. S3, aluminum plating; S4, Topcoat.

[0006] Preferably, the epoxy acrylic resin in the base coating is a self-crosslinking waterborne acrylic emulsion, model DSM 1127, with a solid content of 43.5-45%, a pH value of 7.3-7.9, and a viscosity of 25 175 mPa·s. This resin has the advantages of low odor, fast drying, strong adhesion, and good flexibility.

[0007] Preferably, the TPGDA is a polyester monomer, tripropylene glycol diacrylate, which is a macromolecule with double bonds, has good solubility, and can be dispersed quickly.

[0008] Preferably, the TMPTA is a high-performance photocurable monomer, ethoxylated trimethylolpropane triacrylate, with the functional group being ethoxylated trimethylolpropane. Its advantages include high activity and suitable viscosity, making it suitable as a crosslinking agent in radiation-cured coatings and inks.

[0009] Preferably, the HDDA model is Baiju Technology 7500. HDDA is a highly dispersed tertiary amine with two adjacent amino groups in its molecule. It has the advantages of fast film formation and drying, strong adhesion, flexibility, high gloss, and good anti-yellowing properties. At the same time, its strong dispersibility can mix a variety of incompatible compounds together.

[0010] Preferably, BYK333 is an organosilicon surface additive that can strongly reduce surface tension, has excellent substrate lubrication and leveling properties, is VOC-free and does not affect transparency, has good water and oil solubility, and can provide uniform surface tension to prevent surface defects.

[0011] Preferably, the preparation process of the primer coating is as follows: epoxy acrylic resin, TPGDA, TMPTA, and HDDA are placed in a container and thoroughly stirred and mixed evenly for 15-20 minutes at a stirring speed of 1500-1700 rpm, at a stirring temperature of 25-35°C, and at atmospheric pressure; finally, BYK333 is added, and the stirring time is 20-30 minutes at a stirring speed of 500-700 rpm, at a stirring temperature of 45-50°C, and at atmospheric pressure, and the mixture is stirred and mixed to obtain the final product.

[0012] Preferably, the preparation process of the printing coating is as follows: pure acrylic resin, epoxy acrylic acid, TPGDA, TMPTA, and HDDA are placed in a container and stirred until uniform. The stirring time is 10-15 minutes, the stirring speed is 1200-1500 rpm, the stirring temperature is 25-35℃, and the pressure is atmospheric pressure. Finally, BYK333 is added, and the stirring time is 25-40 minutes, the stirring speed is 300-500 rpm, the stirring temperature is 30-40℃, and the pressure is atmospheric pressure. The mixture is then stirred until the desired coating is obtained.

[0013] The aluminum plating layer is used to provide mirror and partial matte effects. By setting different bright and matte zones through the brightness difference after aluminum plating, a high gloss and matte feel of mirror is formed on the same printed material, and a high contrast of local graphics and text is achieved visually, thus achieving a cold foil stamping effect.

[0014] The surface coating is used to form a protective layer, increasing the abrasion resistance and anti-counterfeiting properties of the printed materials.

[0015] This invention provides a novel method for preparing anti-counterfeiting direct-coated paper, which achieves the effect of cold foil stamping using a non-cold foil stamping process.

[0016] In the base coating, the main resin, epoxy acrylate, works in conjunction with reactive diluents TPGDA, TMPTA, and HDDA to achieve curing, film formation, and performance adjustment. Epoxy acrylate, as the "skeleton" of the curing formulation, has a relatively high viscosity, resulting in a dense cured film with good adhesion, chemical resistance, and strength; however, the coating is somewhat brittle. TPGDA, a bifunctional monomer, has low viscosity and high dilution capacity, significantly reducing the system viscosity. Its moderate crosslinking density balances coating flexibility and hardness, further enhancing adhesion. TMPTA, a trifunctional monomer, effectively increases curing speed, exhibiting high activity and low volatility, with a slightly higher viscosity. Used in combination with the low-viscosity diluent TPGDA, it enhances the crosslinking network density. HDDA, another bifunctional monomer, has low viscosity and high activity. Together with TPGDA, it adjusts the coating viscosity and provides a certain degree of flexibility and elongation, reducing curing shrinkage stress.

[0017] In the printing layer, pure acrylic resin and epoxy acrylate resin are the main film-forming components of this formulation. Pure acrylic resin provides a certain degree of adhesion and produces a soft glossy film. Together with epoxy acrylate resin, it forms the main body of the printing coating. The addition of epoxy acrylate resin can improve coating adhesion, but the overall curing speed is relatively slow. TPGDA, TMPTA, and HDDA, as reactive diluents, mainly function to adjust the coating viscosity and participate in curing. TMPTA is a trifunctional monomer that can improve the curing speed, but its viscosity is relatively high, so a certain proportion of TPGDA and HDDA needs to be added. TMPTA has a high shrinkage rate and is brittle after curing. HDDA can neutralize the brittleness. The proportion of HDDA in the printing layer is relatively low compared to the base layer, allowing the printing layer to exhibit stronger shrinkage and a certain three-dimensional raised effect after curing. The addition of TPGDA can further reduce the viscosity of the coating and provide stable machine adaptability.

[0018] This invention achieves a three-dimensional raised effect on the ink by utilizing the surface tension difference between the base coating and the printing layer, as well as the cohesive reaction of the printing layer. By adjusting the brightness differences after aluminum plating and setting different gloss and matte zones, it creates a mirror-like high-gloss and matte finish on the same printed material, achieving high contrast in localized graphics and text, thus achieving a cold foil stamping effect. This process is simple, fast, and environmentally friendly. Detailed Implementation

[0019] The present invention will now be described in detail with reference to specific embodiments.

[0020] Example 1 A novel anti-counterfeiting direct-coating paper, the process route of which is coating-printing-aluminizing-topcoating. Both the coating and printing ink are self-prepared, as detailed below: (1) Preparation of primer coating: According to the weight percentage, epoxy acrylic resin (20%), TPGDA (30%), TMPTA (20%), and HDDA (29.5%) are placed in a 300mL round-bottom flask equipped with a thermometer, reflux condenser, and water separator. The stirring time is 15 minutes, the stirring speed is 1500 rpm, the stirring temperature is 25℃, and the pressure is atmospheric pressure. After stirring, BYK333 (0.5%) is placed in the container, and the stirring time is 20 minutes, the stirring speed is 500 rpm, the stirring temperature is 45℃, and the pressure is atmospheric pressure. After stirring, impurities are removed by filtration, and the viscosity of the coating is adjusted to meet the requirements for use on the machine to obtain the primer coating.

[0021] (2) Preparation of printing coating: By weight percentage, pure acrylic resin (20%), epoxy acrylic acid (5%), TPGDA (39.8%), TMPTA (20%), and HDDA (15%) were placed in a 300mL round-bottom flask equipped with a thermometer, reflux condenser, and water separator. The stirring time was 10 minutes, the stirring speed was 1200 rpm, the stirring temperature was 25℃, and the pressure was atmospheric pressure. After stirring, 0.2% of BYK333 was added to the container, and the stirring time was 25 minutes, the stirring speed was 300 rpm, the stirring temperature was 30℃, and the pressure was atmospheric pressure. After stirring, impurities were removed by filtration, and the viscosity of the coating was adjusted to meet the requirements for use on the printing press to obtain the printing coating.

[0022] (3) Coating: Conventional coating is carried out on a coating machine with a paper basis weight of 60 g / m2, a coating wet weight of 3.8 g / m2, a coating speed of 120 m / min, and a coating pressure of 20 N.

[0023] (4) Printing: Print the printing coating onto the base layer and use screen printing to form the required graphic pattern. The screen printing mesh number is 350 mesh and the curing speed is ≥80M / min.

[0024] (5) Aluminum plating: Aluminum plating is performed on the printed paper. A thin film of metal aluminum is formed on the surface of the paper through vacuum coating and other methods to increase the anti-counterfeiting effect and visual effect.

[0025] (6) Topcoat: 100-120 line anilox rollers are used to coat the entire printing surface. Select paints or inks with special effects, such as mirror paints or frosted paints, to perform topcoat treatment, which increases the texture and visual effect of the paper.

[0026] Example 2 A novel anti-counterfeiting direct-coating paper has a process route of coating-printing-aluminization-topcoating. Both the coating and printing ink are self-prepared, as detailed below: (1) Preparation of primer coating: According to the weight ratio, epoxy acrylic resin (22%), TPGDA (28%), TMPTA (21%), and HDDA (28.5%) are placed in a container. The stirring time is 20 minutes, the stirring speed is 1700 rpm, the stirring temperature is 35℃, and the pressure is atmospheric pressure. After stirring, 0.5% of BYK333 is added to the container. The stirring time is 30 minutes, the stirring speed is 700 rpm, the stirring temperature is 50℃, and the pressure is atmospheric pressure. After stirring, the primer coating is obtained.

[0027] (2) Preparation of printing coating: According to the weight ratio, pure acrylic resin (24%), epoxy acrylic acid (5%), TPGDA (35.6%), TMPTA (22%), and HDDA (13%) were placed in a container. The stirring time was 15 minutes, the stirring speed was 1500 rpm, the stirring temperature was 35℃, and the pressure was atmospheric pressure. After stirring, 0.4% of BYK333 was added to the container. The stirring time was 40 minutes, the stirring speed was 500 rpm, the stirring temperature was 40℃, and the pressure was atmospheric pressure. After stirring, the printing coating was obtained.

[0028] (3) Coating: Conventional coating is carried out on a coating machine with a paper basis weight of 60 g / m2, a coating wet weight of 3.8 g / m2, a coating speed of 120 m / min, and a coating pressure of 20 N to ensure the formation of a uniform base coating layer.

[0029] (4) Printing: The printing coating is printed on the base coating. Techniques such as offset printing, gravure printing or screen printing can be used to form the desired graphic pattern.

[0030] (5) Aluminum plating: Aluminum plating is performed on the printed paper. A thin film of metal aluminum is formed on the surface of the paper through vacuum coating and other methods to increase the anti-counterfeiting effect and visual effect.

[0031] (6) Topcoat: Select paints or inks with special effects, such as mirror paints or frosted paints, to perform topcoat treatment, thereby increasing the texture and visual effect of the paper.

[0032] Table 1. Weight ratio of primer coatings in Examples 1-2 Table 2. Weight ratio of topcoat paints in Examples 1-2 Table 3 Performance Tests As can be seen from the above test results, the base coating and top coating obtained by the present invention have advantages such as high gloss and high adhesion. At the same time, they can achieve the effect of imitating cold foil stamping, and achieve high contrast of local graphics and text in visual appearance, making the substrate more expressive.

[0033] Compared with existing technologies, the product and preparation process of this invention have the following advantages: 1. The product of this invention can achieve a cold foil stamping effect through a coating process, which is simple. The three-dimensional raised effect of the ink is achieved through the surface tension difference between the base layer and the ink layer, as well as the cohesive reaction of the ink layer. By utilizing the brightness difference after aluminum plating, different high-gloss and matte zones are set, achieving high contrast in localized graphics and text, making the substrate more expressive and achieving the cold foil stamping effect.

[0034] 2. The product of this invention can significantly improve production efficiency and achieve large-scale mass production. The speed of cold ironing is about 80-100 m / min, while the coating speed is about 800-1000 m / min. If the coating process is used instead of the cold ironing process, the efficiency can be increased by about 10 times.

[0035] 3. The product of this invention is cost-effective and environmentally friendly. This process reduces the use of electroplated aluminum film, lowering material and labor costs. Furthermore, the electron beam curing process throughout production results in low solvent emissions, making the process green, safe, and environmentally friendly, meeting environmental protection requirements.

[0036] In summary, this invention provides a novel method for preparing anti-counterfeiting direct-coated paper. Through the interaction between the base coating layer and the printing layer, it achieves both mirror-like high-gloss and matte effects, as well as high-contrast effects in localized graphics and text. This novel anti-counterfeiting direct-coated paper possesses anti-counterfeiting, aesthetic, and decorative characteristics, making it suitable for the packaging industry, decorative materials market, and other fields, and has broad application prospects.

[0037] The scope of protection of this invention is not limited to the above embodiments. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of the claims. Techniques not described in detail in this technical solution are all well-known technologies. Any method for preparing iridescent anti-counterfeiting paper that is the same as or equivalent to the technical solution of this invention falls within the scope of protection of this invention.

Claims

1. A method for preparing a novel anti-counterfeiting direct-coating paper, characterized in that, Includes the following steps: S1, Coating A primer coating is applied to the paper substrate surface. The primer coating formulation comprises the following components by weight percentage: 20-22% epoxy acrylic resin, 28-30% TPGDA, 20-21% TMPTA, 28.5-29.5% HDDA, and 0.5-1% BYK333. S2, Printing A printing layer is applied to the surface of the base layer. The coating formulation of the printing layer comprises the following components by weight percentage: 20-24% pure acrylic resin, 5% epoxy acrylic acid, 35.8-39.8% TPGDA, 20-22% TMPTA, 13-15% HDDA, and 0.2-0.5% BYK333. S3, aluminum plating; S4, Topcoat.

2. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The epoxy acrylic resin used in the base coating is a self-crosslinking waterborne acrylic emulsion of DSM 1127, with a solid content of 43.5-45%, a pH value of 7.3-7.9, and a viscosity of 25 175 mPa·s.

3. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The TPGDA mentioned is a polyester monomer, tripropylene glycol diacrylate.

4. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The TMPTA is a high-performance photocurable monomer, ethoxylated trimethylolpropane triacrylate, with the functional group being ethoxylated trimethylolpropane.

5. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The HDDA mentioned is Baiju Technology 7500. HDDA is a highly dispersed tertiary amine with two adjacent amino groups in its molecule.

6. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The BYK333 is an organosilicon surface additive that can strongly reduce surface tension.

7. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The preparation process of the primer coating is as follows: epoxy acrylic resin, TPGDA, TMPTA, and HDDA are placed in a container and thoroughly stirred and mixed. The stirring time is 15-20 minutes, the stirring speed is 1500-1700 rpm, the stirring temperature is 25-35℃, and the pressure is normal pressure. Finally, BYK333 is added, and the stirring time is 20-30 minutes, the stirring speed is 500-700 rpm, the stirring temperature is 45-50℃, and the pressure is normal pressure. The mixture is then stirred and mixed to obtain the final product.

8. The method for preparing a novel anti-counterfeiting direct-coating paper as described in claim 1, characterized in that, The preparation process of the printing coating is as follows: pure acrylic resin, epoxy acrylic acid, TPGDA, TMPTA, and HDDA are placed in a container and stirred until homogeneous. The stirring time is 10-15 minutes, the stirring speed is 1200-1500 rpm, the stirring temperature is 25-35℃, and the pressure is atmospheric pressure. Finally, BYK333 is added, and the stirring time is 25-40 minutes, the stirring speed is 300-500 rpm, the stirring temperature is 30-40℃, and the pressure is atmospheric pressure. The mixture is then stirred until homogeneous.

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