Cold fixing glue composition with complex functions and its preparation method and application

Abstract

This invention discloses a cold-stamping adhesive composition with composite special effects, its preparation method, and its application. The cold-stamping adhesive composition comprises, by weight percentage: 60%-85% cold-stamping adhesive base, 10%-25% reactive diluent, 2%-15% special effect functional materials, and 1%-10% functional additives; the special effect functional materials are selected from at least one of photochromic materials, thermochromic materials, holographic interference / angle-dependent color pigments, and antibacterial and wear-resistant materials, and have a particle size D50 ≤ 10 μm. In preparation, the functional materials are first pre-dispersed into a slurry, and then blended with the main agent. In application, a UV-LED light source is used for segmented curing: the pre-curing energy is 20-80 mJ / cm² to form the adhesive layer, and the full curing energy after bonding with anodized aluminum foil is 100-300 mJ / cm². This invention integrates cold foil metal decoration with special visual functions, and the aluminum layer transfer and special effects can be completed in one coating. It significantly simplifies the process and improves efficiency. The product has excellent anti-counterfeiting, durability and consistency, and can be widely used in anti-counterfeiting packaging, smart labels, cultural and creative products and other fields.

Description

Technical Field

[0001] This invention relates to the field of printing and packaging technology, and in particular to a cold foil stamping adhesive composition with composite effects, its preparation method, and its application. Background Technology

[0002] Cold foil stamping is an important decorative technique in the printing and packaging industry. Due to its significant advantages such as no heating required, high production efficiency, and energy saving and environmental friendliness, it is widely used in high-end printing and packaging, anti-counterfeiting labels, and cultural and creative products. Its core component is UV cold foil stamping adhesive. The core process involves coating a substrate such as paper or plastic film with UV adhesive, pre-curing it with UV light to achieve a tacky state that is "dry but not sticky, wet but not runny," then bonding it with electroplated aluminum foil. Under certain pressure, selective transfer of the aluminum layer is achieved, and finally, UV light is used for full curing to solidify the pattern, forming a metallic-textured cold foil stamping design.

[0003] Currently, existing cold foil stamping adhesive technologies (such as patents CN103770486B, CN120098575A, CN115477922B, etc.) all revolve around optimizing the basic performance of the cold foil stamping process. The main improvement directions fall into three categories: First, process optimization, establishing a standardized process of "pre-curing - bonding - peeling - full curing" to improve aluminum layer transfer efficiency and production speed; second, performance improvement, optimizing adhesive formulations for different substrates such as uncoated paper and plastics to improve adhesive adhesion and leveling properties, and solve problems such as foil stamping defects and aluminum layer peeling; and third, environmental modification, introducing environmentally friendly components such as bio-based resins to reduce VOC emissions of the adhesive and meet green production requirements.

[0004] With the upgrading of market demand, packaging products not only need metallic decorative effects, but also have higher requirements for anti-counterfeiting, interactivity and added value. They need to achieve special visual effects such as color response under light / temperature changes, holography / angle-dependent color, etc. The functional expansion of cold foil stamping technology has become an industry development trend.

[0005] The current cold foil stamping technology first uses existing mature UV cold foil stamping adhesives (such as epoxy acrylate and polyurethane acrylate-based UV cold foil stamping adhesives) to transfer a metallic aluminum layer onto the substrate through conventional cold foil stamping processes, forming a cold foil stamping pattern. Then, a clear varnish coating containing optically variable or thermochromic functional materials is applied to the surface of the cold foil stamping pattern using methods such as screen printing and coating. Finally, UV curing is performed again to set the functional coating, achieving a combination of the cold foil stamping metallic effect and a special visual effect. This technology requires two independent processes: "cold foil stamping" and "functional coating processing," resulting in a complex process, low production efficiency, and high production costs. Summary of the Invention

[0006] The purpose of this invention is to provide a cold ironing adhesive composition with composite effects, its preparation method, and its application.

[0007] To solve the above technical problems, the present invention adopts the following technical solution: A cold-stamping adhesive composition with composite effects comprises, by weight percentage: Cold stamping adhesive base material 60%–85%, Reactive diluent 10%–25%, Special effects materials 2%–15%, Functional additives 1%–10%; The cold stamping adhesive base material is selected from one or more of epoxy acrylate, polyurethane acrylate, and modified rosin-based acrylate; The special effect functional material is at least one of the following: wall-coated color-changing microcapsules, angle-dependent color-changing powder, nano-silver antibacterial powder, and nano-silica wear-resistant reinforcing powder, and the particle size D50 ≤ 10 μm; wherein the wall-coated color-changing microcapsules include photochromic coated microcapsules and thermochromic coated microcapsules, and the angle-dependent color-changing powder is an angle-changing pigment; The functional additives include two or more of the following: dispersants, coupling agents, leveling agents, defoamers, photoinitiators, crosslinking agents, or abrasion-resistant additives.

[0008] Preferably, the photochromic material is spiropyran, spiroxazine, or their microcapsules; the thermochromic material is a thermosensitive dye microcapsule with a color-changing temperature range of 25–45℃ or 30–60℃; and the holographic interference / angle-dependent heterochromatic pigment is an angle-dependent heterochromatic interference pigment or a vacuum-deposited structural color pigment.

[0009] Preferably, the dispersant is a polycarboxylate or a polymeric block copolymer dispersant; the coupling agent is a titanate coupling agent or a silane coupling agent; and the photoinitiator is a pyrolysis type or a hydrogen abstraction type, suitable for UV-LED light sources.

[0010] Preferably, the antibacterial and wear-resistant material is a mixture of nano-silver and silica micropowder.

[0011] The present invention also provides a method for preparing a cold ironing adhesive composition, comprising the following steps: 1) Pre-dispersion: Mix the special effect functional material, part of the active diluent, dispersant and coupling agent, and disperse at 800-1500 rpm for 10-30 min to obtain the functional slurry; 2) Mixing of main components: Under light-protected conditions, stir the cold stamping adhesive base, remaining reactive diluent, and leveling / defoaming agent at 300–500 rpm until homogeneous to obtain the adhesive base; 3) Blending and fine dispersion: Add the special effect functional slurry to the glue base and stir at 500–800 rpm for 20–40 minutes; 4) Add homogenizer: Add photoinitiator and crosslinking agent, and continue stirring at ≤45℃ for 10–20 min; 5) Filtering and filling: Filter through a 100–200 mesh filter and store in a sealed container away from light.

[0012] This invention also provides an application process for a cold-stamping adhesive with composite effects, which further includes the following steps when using the above-mentioned cold-stamping adhesive: 1) Coating: Applying cold foil adhesive to the substrate using gravure, flexographic, or offset printing methods; 2) UV pre-curing: Using a UV-LED light source, irradiation with energy of 20–80 mJ / cm² is used to form an adhesive layer; 3) Bonding and Transfer: Bond the electroplated aluminum foil and apply a pressure of 0.2–0.8 MPa to transfer the aluminum layer; 4) Peeling: Peel off the electroplated aluminum base film to form a composite special effect cold foil pattern; 5) UV full curing: Complete curing with 100–300 mJ / cm² energy.

[0013] Preferably, the printing substrate is paper, plastic film, or metal sheet.

[0014] Preferably, the UV pre-curing energy is controlled at 40–60 mJ / cm², which ensures the transfer adhesion of the aluminum layer and avoids the deactivation of special effect functional materials.

[0015] This invention also discloses the application of the aforementioned cold foil stamping adhesive with composite effects in anti-counterfeiting packaging, smart labels, cultural and creative products, and high-end gift packaging.

[0016] An integrated composite special effect cold stamping product includes a substrate, an electroplated aluminum layer, and a cold stamping adhesive curing layer of the present invention. The cold stamping adhesive curing layer and the electroplated aluminum layer are integrally bonded together, eliminating the need for secondary printing or coating of functional coatings.

[0017] Compared with the prior art, the present invention has the following outstanding advantages: 1. Functional integration, multiple uses of one adhesive: It creatively combines the metal decoration function of cold foil stamping with optical / thermal effects, simplifying the production process, eliminating the need for subsequent secondary coating or printing processes, and significantly improving production efficiency and product reliability.

[0018] 2. Excellent anti-counterfeiting and interactivity: Color-changing and holographic effects are difficult to imitate through ordinary scanning and copying, greatly enhancing the product's anti-counterfeiting level. Thermochromic and photochromic color-changing effects increase the packaging's fun and interactive experience, enhancing the product's added value.

[0019] 3. Excellent process compatibility and durability: Through a specific functional additive system (dispersant, coupling agent, crosslinking agent), the industry problems of uneven dispersion of special functional materials in adhesives, incompatibility with processes, and easy detachment and failure are solved, ensuring the stability and longevity of the special effects.

[0020] 4. Wide applicability: The adhesive of this invention is compatible with existing cold foil stamping equipment. With the optimization of curing parameters, it can achieve good results on a variety of substrates such as coated paper, uncoated paper, plastic, and metal, making it suitable for a wide range of applications. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to specific examples.

[0022] The technical solution of this invention revolves around three core parts: a cold-stamping adhesive composition with composite effects, a method for preparing the adhesive, and a cold-stamping application process for the adhesive. These three components work synergistically to achieve the integration of cold-stamping metallic decorative function and special visual function, eliminating the need for secondary processing. The following is a detailed description: (a) Cold ironing adhesive composition with composite effects This adhesive composition, by weight percentage, consists of cold-stamping adhesive base (60%-85%), reactive diluent (10%-25%), special effect functional materials (2%-15%), and functional additive system (1%-10%). The precise proportions and compatibility of each component are as follows: Cold foil adhesive base: This is the core matrix of the adhesive, selected from one or more UV-curable resins among epoxy acrylate, polyurethane acrylate, and modified rosin-based acrylate (such as Changxing's 6210G, 6233, 6113 and Xiamen Weier Chemical's WUV-22C, 8026). It provides the adhesive with basic film-forming properties, adhesion, and UV curing reactivity, ensuring the transfer effect of the cold foil aluminum layer.

[0023] Reactive diluents: Selected from monofunctional or polyfunctional acrylate monomers (such as TMPTA, TPGDA, HDDA, IBOA), which on the one hand adjust the viscosity of the adhesive to adapt to different coating methods such as gravure, flexographic and offset printing; on the other hand, participate in the UV curing reaction to improve the crosslinking density and hardness of the adhesive layer.

[0024] Special effect functional materials: As the core component for achieving composite special effects, the special effect functional materials are at least one of the following: wall-coated color-changing microcapsules, angle-dependent color-changing powder, nano-silver antibacterial powder, and nano-silica wear-resistant reinforcing powder, with a particle size D50≤10μm, ensuring uniform dispersion in the adhesive and a smooth adhesive layer surface after coating; wherein the wall-coated color-changing microcapsules include photochromic coated microcapsules and thermochromic coated microcapsules, and the angle-dependent color-changing powder is an angle-changing pigment; Optical / photochromic materials: such as spiropyrans, spiroxazine compounds or their microcapsules, to achieve color changes under light; Thermochromic materials: such as microcapsules composed of thermosensitive dyes, color developers, and co-solvents, with color-changing temperature ranges of 25-45℃, 30-60℃, etc., to achieve temperature-triggered color changes; Holographic interference / angle-dependent heterochromatic pigments: pigments with angle-dependent heterochromatic interference or vacuum-deposited structural color pigments; Long-lasting antibacterial / wear-resistant functional materials: such as nano silver and silica micro powder, to achieve practical functions such as antibacterial and scratch resistance.

[0025] Functional additive system: This is a composite additive system designed to address compatibility, dispersibility, process suitability, and durability issues. The components and their functions are as follows: Dispersants: polycarboxylate and hyperbranched block copolymers (Lubrizol Solsperse 20000, 24000, 32000) stabilize special effect functional materials and prevent them from agglomerating and settling; Coupling agents: silane coupling agents (KH-550 / KH-560 / KH-570, etc.) enhance the interfacial bonding force between functional materials and resin matrix, and strengthen the cohesive strength of the adhesive layer; Leveling / Defoaming agents: silicone or fluorocarbon (such as BYK-333, BYK-052) to optimize the leveling properties of the adhesive, eliminate bubbles generated during the coating process, and ensure a smooth adhesive layer surface; Photoinitiators: pyrolysis type (such as 1173, 184) or hydrogen abstraction type (such as ITX, TPO, TMO), adapted to UV-LED light sources, precisely triggering UV curing reactions; Crosslinking agent / abrasion resistant agent: Isocyanate crosslinking agent (Karenz BEI), nano silica, to improve the scratch resistance, weather resistance and chemical resistance of the cured adhesive layer.

[0026] (II) Preparation method of cold ironing adhesive with composite effects The core technology of this preparation method is to pre-disperse the functional slurry before blending it with the main agent. This avoids the agglomeration of functional materials, ensures uniform dispersion of each component, and balances the stability of the adhesive and the activity of the functional materials throughout the process. Specific steps are as follows: Pre-dispersion: Mix the special effect functional material, part of the active diluent, all the dispersant and coupling agent, and place them in a high-speed disperser at a speed of 800-1500 rpm for 10-30 minutes to form a uniform functional slurry, break up the agglomerates of functional materials, and achieve preliminary dispersion.

[0027] Mixing the main agent: Under light-protected conditions, add the cold stamping adhesive base, remaining reactive diluent, and leveling / defoaming agent to the mixing tank, and stir at a low speed of 300-500 rpm to form the adhesive base. Stir at a low speed to avoid generating bubbles.

[0028] Blending and fine dispersion: Slowly add the functional slurry prepared in step 1 to the adhesive base in step 2. First, mix at low speed until preliminary fusion, then adjust the speed to 500-800 rpm and stir for 20-40 minutes to achieve fine and uniform mixing of functional materials and base.

[0029] Post-addition and homogenization: Add photoinitiator, crosslinking agent and other additives to the blended adhesive solution, and continue to stir at 300-500 rpm for 10-20 minutes at a temperature not exceeding 45°C to ensure that all components of the adhesive solution are completely homogenized.

[0030] Filtration and filling: Filter the adhesive liquid with a 100-200 mesh filter to remove any large particles that may be present in the adhesive liquid. Then fill the finished product into an opaque container and seal it for storage to prevent premature reaction of the photoinitiator.

[0031] (III) Application process of cold-stamping adhesive with composite effects This application process is compatible with existing cold foil stamping equipment. The core technology involves precisely controlling the UV pre-curing energy (below the failure threshold of the functional materials), balancing the formation of the adhesive layer required for cold foil stamping with the protection of the functional materials' activity. Subsequent full curing achieves high hardness and high durability of the adhesive layer. Specific steps are as follows: Coating: The cold foil stamping adhesive of the present invention is applied evenly to the surface of the substrate (paper, plastic film, metal sheet, etc.) according to a preset pattern by gravure, flexographic or offset printing. The coating thickness is adjusted according to product requirements.

[0032] UV Pre-curing: The coated adhesive is irradiated with a UV-LED light source, with the curing energy controlled between 20-80 mJ / cm². This allows for initial curing of the adhesive surface, forming an viscous layer that is "wet but not runny, dry but not sticky." This energy range ensures sufficient adhesion for aluminum layer transfer while preventing excessive UV light from deactivating functional materials. Below 20 mJ / cm², the UV initiator is only minimally activated, resulting in insufficient cross-linking of the adhesive layer and an inability to form the critical adhesion required for aluminum layer transfer, leading to incomplete transfer and rough edges after electroplated aluminum bonding. Above 80 mJ / cm²... 2 At this time, high-energy UV radiation can directly penetrate the organic wall material of photochromic / thermochromic microcapsules, destroy the color-changing active material in the core, causing permanent failure of the color-changing function. Simultaneously, excessive cross-linking of the adhesive layer leads to brittleness, and a sharp drop in the adhesion of the aluminum layer results in oxidation and discoloration. (The radiation intensity is only 20–80 mJ / cm³.) 2 Within the specified range, the adhesive layer can be made into a critical tack state that is neither dry nor sticky, while protecting the integrity of the microcapsule wall material. This satisfies the bonding requirements for the transfer of the roll-pressed aluminum layer and preserves functional activities such as color change and antibacterial properties.

[0033] Bonding and Transfer: Anodized aluminum foil is bonded to the pre-cured adhesive layer. A pressure of 0.2-1 MPa is applied by a pressure roller, which selectively transfers the aluminum layer of the anodized aluminum foil to the adhesive portion of the substrate under the action of adhesion.

[0034] Peeling: After the pressure bonding is completed, peel off the base film of the electroplated aluminum foil. At this time, the aluminum layer and the adhesive layer containing special functional materials are tightly bonded together to form the preset cold stamping pattern on the substrate.

[0035] UV full curing: using a higher energy UV-LED light source (curing energy controlled at 100-300 mJ / cm). 2 The cold foil pattern is thoroughly cured, allowing the adhesive to fully cross-link and form a film, creating a composite cold foil graphic with high hardness, high adhesion, and high durability, ensuring the product's durability and special effect stability.

[0036] Example 1 A cold-stamping adhesive composition with composite effects, comprising the following components by weight percentage: Cold stamping adhesive base: Polyurethane acrylate (Changxing 6113) 72%; Reactive diluent: 12% TMPTA + 8% TPGDA; Special effect functional material: 3% of 5μm spiropyran-coated microcapsules (Product name: photosensitive powder; Model: carmine; Manufacturer: Guangzhou Chongyu Industrial Materials Technology Co., Ltd., Abbreviation: Chongyu photosensitive color-changing carmine); Functional additives: Polycarboxylate dispersant (Lubrizol Solsperse 20000) 1.5% + KH-550 0.8% + BYK-333 0.5% + Photoinitiator (1173 + TPO=1:1) 1.2% + Crosslinking agent (Lysenko Karenz BEI) 1%.

[0037] The preparation method is as follows: Pre-dispersion: Mix the special effect functional material, part of the active diluent, all the dispersant and coupling agent, and place them in a high-speed disperser at a speed of 1200 r / min for 20 minutes to form a uniform functional slurry, break up the agglomerates of functional materials, and achieve preliminary dispersion; Mixing the main agent: Under light-protected conditions, add the cold stamping adhesive base, remaining reactive diluent, and leveling / defoaming agent to the mixing tank and stir at a low speed of 400 r / min until uniform to form the adhesive base. Stir at a low speed to avoid generating bubbles. Blending and fine dispersion: The functional slurry prepared in step 1 is slowly added to the adhesive base in step 2. First, it is mixed at a low speed until it is initially fused, and then the speed is adjusted to 600 r / min and stirred for 30 min to achieve fine and uniform mixing of functional materials and base. Post-addition and homogenization: Add photoinitiator, crosslinking agent and other additives to the blended adhesive solution, and continue to stir at 350 r / min for 15 minutes at a temperature not exceeding 40°C to ensure that all components of the adhesive solution are completely homogenized; Filtration and filling: Filter the adhesive liquid with a 150-mesh filter to remove any large particles that may be present in the adhesive liquid. Then fill the finished product into an opaque container, seal it, and store it at 20°C to prevent premature reaction of the photoinitiator.

[0038] The application process is as follows: Coating: The cold foil adhesive of this invention is applied evenly to the surface of the substrate (paper, plastic film, metal sheet, etc.) according to a preset pattern using a gravure printing method. The coating thickness is adjusted according to product requirements. UV pre-curing: The coated adhesive is irradiated with a 365nm UV-LED light source, and the curing energy is controlled at 40mJ / cm², so that the surface of the adhesive is initially cured and forms an adhesive layer that is "wet but not runny, dry but not sticky". Bonding and Transfer: Anodized aluminum foil is bonded to the pre-cured adhesive layer. A pressure of 0.6 MPa is applied by a pressure roller, which selectively transfers the aluminum layer of the anodized aluminum foil to the adhesive portion of the substrate under the action of adhesion. Peeling: After the pressure bonding is completed, peel off the base film of the electroplated aluminum foil. At this time, the aluminum layer and the adhesive layer containing special functional materials are tightly bonded together to form the preset cold stamping pattern on the substrate. UV Full Curing: Using a higher-energy UV-LED light source, the curing energy is controlled at 200mJ / cm² to thoroughly cure the cold foil pattern, allowing the adhesive to fully cross-link into a film, forming a composite special effect cold foil graphic with high hardness, high adhesion, and high durability, ensuring the product's durability and special effect stability.

[0039] Examples 2-5 are prepared in the same way as Example 1, except for some process parameters, as shown in the table below. All examples strictly follow the composition ratio, preparation process and application process of the present invention. All performance tests are based on industry standards (adhesion: ASTM D3359; abrasion resistance: ISO 105-X12; color difference: CIE Lab; antibacterial: JIS Z 2801; storage stability: stored at room temperature away from light and in a sealed container).

[0040]

[0041] Comparative examples were conducted based on Example 1, with some parameters changed, and the results were studied, as shown in the table below:

[0042] The necessity of adding functional material with a particle size D50 ≤ 10 μm (changing only the particle size) based on Example 1 is shown in the table below:

[0043] Based on Example 1, the pre-curing energy of the present invention was investigated by only changing the pre-curing energy, as shown in the table below:

[0044] Based on Example 1, the necessity of adding special effect functional materials in a wide range of amounts (2%–15%) was verified.

[0045] Conclusions: <2%: Insufficient composite function, lacking industrial application value; >15%: Viscosity out of control, severe agglomeration, sharp drop in transfer rate, and instability failure; 2% to 15%: Optimal synergy of special effects, rheology, transfer, and storage, with sufficient experimental basis and technical necessity within this range.

[0046] In summary, the present invention has the following beneficial effects: 1. Efficiency and Production Capacity: Eliminating the need for secondary coating and curing increases overall production capacity by ≥50% and significantly optimizes cycle time; pilot-scale testing demonstrates high-speed production at 80m / min, with a single batch size of ≥5000㎡ and continuous operation for 8 hours without failure; 2. Interface strength: Integrated chemical bonding, 4B or higher cross-link strength, wear resistance ≥500 times for 500g, no peeling when bent, and no degradation after 1000 cycles of high and low temperature cycling (-20℃~60℃). 3. Uniform appearance: The film thickness is uniform in a single pass, the color difference ΔE < 1.5, and the yield rate is increased to over 97% (compared to 72% for traditional processes). 4. Cost reduction advantages: Reducing workstations, energy consumption, and varnish consumables reduces overall production costs by 25% to 35%, with the cost per square meter decreasing from 1.8 yuan to 1.3 yuan; 5. Anti-counterfeiting level: Triple dynamic anti-counterfeiting with light control + temperature control + corner-specific color change, which cannot be imitated by conventional scanning and copying, doubling the added value; 6. Safety and compliance: Benzene-free and low VOC (≤15g / L), nano-silver long-lasting antibacterial effect (antibacterial rate ≥99.2%), heavy metal migration ≤0.01mg / dm², in compliance with the GB 4806.10-2016 standard for indirect food contact. 7. Compatible with localization: Existing equipment can be used without modification, and it is compatible with multiple substrates (paper, PET / PP, aluminum foil, etc.). Mass production can be achieved with only minor adjustments to the UV energy, enabling small and medium-sized enterprises to start production quickly and at low cost. 8. Synergistic Effects: Combining functions produces unexpected results: The homogeneous compatibility design improves adhesion from the conventional 3B to 4B+; The corner-dependent color-changing powder forms a "micromirror reflection layer", which increases color saturation by 30% (L* value increases from 75 to 98); The antibacterial powder compensates for the decrease in hardness of the microcapsule layer, increasing the wear resistance from 300 cycles to over 500 cycles.

[0047] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A cold fixing glue composition having a complex effect, characterized in that, Included by weight percentage: Cold stamping adhesive base material 60%–85%, Reactive diluent 10%–25%, Special effects materials 2%–15%, Functional additives 1%–10%; The cold stamping adhesive base material is selected from one or more of epoxy acrylate, polyurethane acrylate, and modified rosin-based acrylate; The special effect functional material is at least one of the following: wall-coated color-changing microcapsules, angle-dependent color-changing powder, nano-silver antibacterial powder, and nano-silica wear-resistant reinforcing powder, and the particle size D50 ≤ 10 μm; wherein, the wall-coated color-changing microcapsules include photochromic coated microcapsules and thermochromic coated microcapsules, and the angle-dependent color-changing powder is an angle-changing pigment; The functional additives include two or more of the following: dispersants, coupling agents, leveling agents, defoamers, photoinitiators, crosslinking agents, or abrasion-resistant additives.

2. The cold fixing glue composition with complex functions according to claim 1, characterized in that: The photochromic material is spiropyran, spiroxazine, or their microcapsules; the thermochromic material is a thermosensitive dye microcapsule with a color-changing temperature range of 25–45℃ or 30–60℃; the holographic interference / angle-dependent heterochromatic pigment is an angle-dependent heterochromatic interference pigment or a vacuum-deposited structural color pigment.

3. The cold fixing glue composition with complex functions according to claim 1, characterized in that: The dispersant is a polycarboxylate or a high molecular block copolymer dispersant; the coupling agent is a titanate coupling agent or a silane coupling agent; the photoinitiator is a pyrolysis type or a hydrogen abstraction type, suitable for UV-LED light sources.

4. The cold fixing glue composition with complex functions according to claim 1, characterized in that: The antibacterial and wear-resistant material is a mixture of nano-silver and silica micropowder.

5. A method of preparing a cold melt glue composition according to any one of claims 1 - 4, characterized in that, Includes the following steps: 1) Pre-dispersion: Mix the special effect functional material, part of the active diluent, dispersant and coupling agent, and disperse at 800-1500 rpm for 10-30 min to obtain the functional slurry; 2) Mixing of main components: Under light-protected conditions, stir the cold stamping adhesive base, remaining reactive diluent, and leveling / defoaming agent at 300–500 rpm until homogeneous to obtain the adhesive base; 3) Blending and fine dispersion: Add the special effect functional slurry to the glue base and stir at 500–800 rpm for 20–40 minutes; 4) Add homogenizer: Add photoinitiator and crosslinking agent, and continue stirring at ≤45℃ for 10–20 min; 5) Filtering and filling: Filter through a 100–200 mesh filter and store in a sealed container away from light.

6. A process for the application of a cold fix glue having complex effects, using the cold fix glue according to any one of claims 1-4 or the cold fix glue prepared according to the method of claim 5, characterized in that, include: 1) Coating: Applying cold foil adhesive to the substrate using gravure, flexographic, or offset printing methods; 2) UV pre-curing: Using a UV-LED light source, irradiation with energy of 20–80 mJ / cm² is used to form an adhesive layer; 3) Bonding and Transfer: Bond the electroplated aluminum foil and apply a pressure of 0.2–0.8 MPa to transfer the aluminum layer; 4) Peeling: Peel off the electroplated aluminum base film to form a composite special effect cold foil pattern; 5) UV full curing: Complete curing with 100–300 mJ / cm² energy.

7. The process for use according to claim 6, characterized in that, The printing substrate is paper, plastic film, or metal sheet.

8. The application process of claim 6, wherein, The UV pre-curing energy is controlled at 40–60 mJ / cm², which ensures the transfer adhesion of the aluminum layer and avoids the deactivation of special effect functional materials.

9. The application of the cold foil stamping adhesive with composite effects as described in any one of claims 1–4 in anti-counterfeiting packaging, smart labels, cultural and creative products, and high-end gift packaging.

10. An integrated composite special effect cold peel product, characterized by, It comprises a substrate, an electroplated aluminum layer, and a cold-stamping adhesive curing layer as described in any one of claims 1-4, wherein the cold-stamping adhesive curing layer is integrally bonded to the electroplated aluminum layer, without the need for secondary printing or coating of functional coatings.

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