Preparation method of transfer film with cat eye lens positioning pattern

Abstract

The invention belongs to the technical field of laser packaging materials, and discloses a preparation method of a transfer film with cat eye lens positioning patterns. The preparation method comprises the following steps: preparing first-coating transfer coating paint and second-coating transfer coating paint; a PET base film is taken and sequentially coated with the first-coating transfer coating paint and the second-coating transfer coating paint, a transfer coating is formed, and a PET transfer base film is prepared; then hot-pressing a laser layer on the transfer coating of the PET transfer base film; and finally, plating aluminum on the laser layer to prepare the transfer film. A coating layer such as a double-coating acrylate copolymer is used as a base film transfer layer, the original nickel plate cat eye lens positioning pattern can be perfectly recarved on a PET transfer film through hot pressing by optimizing a double-transfer coating formula, the lens effect equal to that of a UV process is achieved, the lens stereoscopic impression is clear, the fidelity and reducibility are high, and the appearance is attractive. The flexibility and the folding resistance are higher; and the production cost can be reduced by more than 60%.

Description

Technical Field

[0001] The invention belongs to the technical field of laser packaging materials, and in particular relates to a method for preparing a transfer film with a cat's eye lens positioning pattern. Background Art

[0002] The transfer film of cat's eye lens positioning pattern is a new high-end anti-counterfeiting packaging material for holographic positioning printing packaging. The existing process technology uses UV varnish coating layer for molding to highly restore the deep-grained cat's eye lens effect of nickel plate imitation. However, the production cost of this process is relatively high, so it is also subject to many restrictions when applied to various paper packaging products such as tobacco, alcohol, milk powder, toothpaste, and cosmetics. In addition, the UV transfer film prepared by molding with UV varnish coating layer has poor flexibility and folding resistance, and obvious white creases are easy to appear during the packaging process.

[0003] Therefore, there is an urgent need to provide a method for preparing a transfer film with low production cost and good lens effect and strong flexibility and folding resistance. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a method for preparing a transfer film with a cat's eye lens positioning pattern. The transfer film prepared by the present invention has low preparation cost, good lens effect, and strong flexibility and folding resistance.

[0005] The invention provides a method for preparing a transfer film with a cat's eye lens positioning pattern.

[0006] Specifically, a method for preparing a transfer film having a cat's eye lens positioning pattern comprises the following steps:

[0007] Prepare a first transfer coating paint and a second transfer coating paint; take a PET base film, apply the first transfer coating paint and the second transfer coating paint in sequence to form a transfer coating layer to obtain a PET transfer base film; then heat-press a laser layer on the transfer coating layer of the PET transfer base film; finally, aluminum is plated on the laser layer to obtain a transfer film;

[0008] The one-coat transfer coating comprises the following raw material components by weight percentage: 21%-25% acrylate copolymer, 10%-15% cellulose acetate propionate, 10%-15% cellulose acetate butyrate, 10%-15% cellulose acetate, 20%-25% ethyl acetate and 20%-28% butanone;

[0009] The two-coat transfer coating comprises the following raw material components by weight percentage: 16%-20% acrylate copolymer, 10%-15% cellulose acetate propionate, 10%-15% cellulose acetate butyrate, 10%-15% cellulose acetate, 20%-25% ethyl acetate, 5%-10% n-propyl acetate and 20%-28% butanone.

[0010] In some embodiments of the present invention, the dry coating weight of the transfer coating formed by the transfer coating is 1.5-2.0 g / m 2 The dry coating amount of the second transfer coating formed by the second transfer coating paint is 1.0-1.4g / m 2 The total dry coating amount of the transfer coating is 2.8-3.0g / m 2 Preferably, the dry coating amount of the transfer coating formed by the transfer coating is 1.7-1.8 g / m 2 The dry coating amount of the second transfer coating formed by the second transfer coating paint is 1.1-1.2g / m 2 The total dry coating amount of the transfer coating is 2.8-3.0g / m 2 .

[0011] In some embodiments of the present invention, the preparation process of the first transfer coating is: mixing the raw material components, and then stirring at a uniform speed of 2000-3000rpm / min for 0.5-1.0h; the preparation process of the second transfer coating is: mixing the raw material components, and then stirring at a uniform speed of 2000-3000rpm / min for 0.5-1.0h.

[0012] In some embodiments of the present invention, a mesh roller is used for coating, and the mesh number of the mesh roller is 150-200 meshes; the coating speed is 100-110 m / min, and the drying efficiency is 83%-88%.

[0013] In some embodiments of the present invention, during the coating process, the humidity of the production environment is controlled to be 55%-65% and the temperature to be 19° C.-25° C.

[0014] In some embodiments of the present invention, the process of hot pressing the laser layer is: hot pressing is performed under the conditions of a plate roller temperature of 185-195°C, a pressure of 38-42kg / cm, and a speed of 30-50m / min. During hot pressing, the plate roller temperature and the pressure and speed of the pressing roller during lamination are adjusted within the above range to achieve the transparent effect of the cat's eye lens, and there should be no white print that affects the clarity of the cat's eye lens. The transfer coating applied in the present invention has high flexibility, high reducibility and high temperature resistance to the nickel plate, and the hot pressing effect presents a clear and transparent 3D stereoscopic pattern.

[0015] In some embodiments of the present invention, the aluminum plating process is: using aluminum wire with a purity of more than 99.75% under a vacuum pressure of 6.0×10 -4 mbar or more, a high vacuum aluminum coating machine is used to evaporate the laser layer with a thickness of of aluminum layer.

[0016] The transfer film provided by the present invention comprises a PET base film, a transfer coating coated on the PET base film, and the transfer coating comprises a first transfer coating and a second transfer coating, wherein the coating coating is mainly composed of an acrylate copolymer, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate, ethyl acetate and butanone, wherein the acrylate copolymer can improve the high flexibility and scratch resistance of the transfer coating, and the cellulose acetate can improve the tensile properties of the transfer coating, thereby improving the high flexibility of the transfer coating. Through the double-coating design, on the one hand, the poor leveling of the surface after the one-time coating reaches the total dry coating amount of the coating can be solved, which affects the bearing laser effect after molding (hot pressing); on the other hand, the present invention can further improve the leveling of the second transfer coating by reducing the content of the acrylate copolymer in the second transfer coating and increasing the use of n-propyl acetate, so that the bearing laser layer after hot pressing has a more beautiful effect.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention uses a double-coated acrylic copolymer coating layer as a base film transfer layer. By optimizing the double transfer coating formula, the original nickel plate cat's eye lens positioning pattern can be perfectly reproduced on the PET transfer film under high temperature and high pressure conditions, and can achieve the same lens effect as the UV process. The 3D lens has a clear stereoscopic effect and high fidelity restoration. In addition, the production cost can be reduced by more than 60%. After the PET cat's eye lens positioning pattern transfer film is transferred to paper, it can be widely used in various paper packaging products such as cigarettes, alcohol, milk powder, toothpaste, cosmetics, etc.

[0019] (2) The transfer film prepared by the present invention has excellent flexibility and folding resistance, and is more environmentally friendly than the UV transfer coating in terms of material environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a rendering of a transfer film having a cat's eye lens positioning pattern prepared in Example 1 of the present invention;

[0021] Figure 2 This is a rendering of a transfer film having a cat's eye lens positioning pattern prepared in Comparative Example 1;

[0022] Figure 3 This is a comparison chart of the folding resistance test of Example 1 and Comparative Example 1;

[0023] Figure 4 This is a partial effect diagram of the transfer film with a cat's eye lens positioning pattern prepared in Comparative Example 2;

[0024] Figure 5 This is a partial rendering of the transfer film with a cat's eye lens positioning pattern prepared in Comparative Example 3. DETAILED DESCRIPTION

[0025] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0026] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0027] Example 1

[0028] A method for preparing a transfer film having a cat's eye lens positioning pattern comprises the following steps:

[0029] (1) Preparation of PET transfer base film

[0030] Prepare a first-coat transfer coating and a second-coat transfer coating, wherein the first-coat transfer coating includes the following raw material components by weight percentage: 22% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 12% cellulose acetate, 22% ethyl acetate and 20% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use. The second-coat transfer coating includes the following raw material components by weight percentage: 18% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 11% cellulose acetate, 21% ethyl acetate, 6% n-propyl acetate and 20% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use.

[0031] Take the PET base film, use a steel mesh roller with 150 mesh, and coat it at a coating speed of 105m / min and a drying efficiency of 85%. First, apply a transfer coating layer, and control the dry coating amount of the transfer coating layer to 1.8g / m 2 ; Then apply the second transfer coating on the first transfer coating, and control the dry coating amount of the second transfer coating to 1.2g / m 2 ; Total dry coating weight 3.0g / m 2 , a PET transfer base film was obtained. During the coating process, the coating humidity was controlled at 60% and the temperature was controlled at 23°C.

[0032] (2) Hot pressing laser layer on the transfer coating on the PET transfer base film

[0033] The laser layer with the cat's eye positioning pattern laser effect on the nickel plate is molded and replicated onto the transfer coating of the PET transfer base film through a hot pressing process. During the molding process, the plate roller temperature is 188°C, the pressure of the roller is 40kg / cm, and the speed is 40m / min.

[0034] (3) Aluminum coating on the laser layer

[0035] Using 99.80% pure aluminum wire, the vacuum pressure is 6.2×10 -4 mbar, a layer of aluminum was evaporated on the laser layer by a high vacuum aluminum coating machine with a thickness of

[0036] Example 2

[0037] A method for preparing a transfer film having a cat's eye lens positioning pattern comprises the following steps:

[0038] (1) Preparation of PET transfer base film

[0039] Prepare a first-coat transfer coating and a second-coat transfer coating, wherein the first-coat transfer coating includes the following raw material components by weight percentage: 25% acrylate copolymer, 10% cellulose acetate propionate, 10% cellulose acetate butyrate, 12% cellulose acetate, 20% ethyl acetate and 28% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use. The second-coat transfer coating includes the following raw material components by weight percentage: 16% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 11% cellulose acetate, 21% ethyl acetate, 8% n-propyl acetate and 20% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use.

[0040] Take the PET base film, use a steel mesh roller with 200 mesh, and coat it at a coating speed of 110m / min and a drying efficiency of 88%. First, apply a transfer coating layer, and control the dry coating amount of the transfer coating layer to 1.7g / m 2 ; Then apply the second transfer coating on the first transfer coating, and control the dry coating amount of the second transfer coating to 1.1g / m 2 ; Total dry coating weight 2.8g / m 2 , a PET transfer base film was obtained. During the coating process, the coating humidity was controlled at 60% and the temperature was controlled at 23°C.

[0041] (2) Hot pressing laser layer on the transfer coating on the PET transfer base film

[0042] The laser layer with the cat's eye positioning pattern laser effect on the nickel plate is molded and replicated onto the transfer coating of the PET transfer base film through a hot pressing process. During the molding process, the plate roller temperature is 188°C, the pressure of the roller is 40kg / cm, and the speed is 40m / min.

[0043] (3) Aluminum coating on the laser layer

[0044] Using 99.80% pure aluminum wire, the vacuum pressure is 6.2×10 -4 mbar, a layer of aluminum was evaporated on the laser layer by a high vacuum aluminum coating machine with a thickness of

[0045] Comparative Example 1

[0046] A method for preparing a UV transfer film having a cat's eye lens positioning pattern comprises the following steps:

[0047] (1) Preparation of PET transfer base film

[0048] The transfer coating is prepared by coating the corona-treated side of the PET base film with a water-based coating and drying the coating to obtain a water-based transfer layer. The water-based coating is composed of 92% by weight of a water-based polyurethane resin and 8% of a leveling agent.

[0049] Take the PET composite base film, use a steel mesh roller with 200 mesh, coat it at a coating speed of 105m / min and a drying efficiency of 93%, and apply a transfer coating until the total dry coating amount of the coating is 1.3g / m 2 , a PET transfer base film was obtained. During the coating process, the coating humidity was controlled at 60% and the temperature was controlled at 23°C.

[0050] (2) Preparation of UV laser information layer

[0051] UV resin is coated on the water-based coating, and the laser cat's eye lens effect is embossed through a nickel plate, and then the UV resin is cured by ultraviolet light to obtain a UV cat's eye lens laser information layer. The UV resin layer is composed of 95% by weight of an ester mixture, 1% of a light shadow, and 4% of a leveling agent. A steel mesh roller with 160 mesh is used, and the UV film pressing speed is 40m / min, and the UV lamp drying power is 18KW. The dry coating amount of the UV resin layer is 8g / m 2 During the production process, the humidity is controlled at 60% and the temperature is 23℃.

[0052] (3) Aluminum coating on the laser layer

[0053] Using 99.80% pure aluminum wire, the vacuum pressure is 6.2×10 -4 mbar, a layer of aluminum was evaporated on the laser layer by a high vacuum aluminum coating machine with a thickness of

[0054] Compared with the preparation process of UV transfer film, the dry coating amount of water-based transfer layer coating is 1.2-1.3g / m 2 , the dry coating amount of UV resin layer is 7-8g / m 2 , the total dry coating weight is 8.2-9.3g / m 2 The total dry coating amount of the double coating hot pressing process is 2.8-3.0g / m 2 , production costs were reduced by more than 60%.

[0055] Comparative Example 2

[0056] Comparative Example 2 provides a method for preparing a transfer film having a cat's eye lens positioning pattern. The difference between Comparative Example 2 and Example 1 is that a transfer coating is directly coated on the PET base film to a total dry weight of 3.0 g / m 2 , specifically including the following steps:

[0057] (1) Preparation of PET transfer base film

[0058] A one-coat transfer coating is prepared, and the one-coat transfer coating comprises the following raw material components by weight percentage: 22% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 12% cellulose acetate, 22% ethyl acetate and 20% butanone. Before coating, the raw material components are mixed, and then stirred at a uniform speed of 2500 rpm / min for 1.0 h and set aside.

[0059] Take the PET base film, use a steel mesh roller with 100 mesh, and coat it at a coating speed of 105m / min and a drying efficiency of 88%. Apply a transfer coating until the total dry coating amount of the coating is 3.0g / m 2 , a PET transfer base film was obtained. During the coating process, the coating humidity was controlled at 60% and the temperature was controlled at 23°C.

[0060] (2) Hot pressing laser layer on the transfer coating on the PET transfer base film

[0061] The laser layer with the cat's eye positioning pattern laser effect on the nickel plate is molded and replicated onto the transfer coating of the PET transfer base film through a hot pressing process. During the molding process, the plate roller temperature is 188°C, the pressure of the roller is 40kg / cm, and the speed is 40m / min.

[0062] (3) Aluminum coating on the laser layer

[0063] Using 99.80% pure aluminum wire, the vacuum pressure is 6.2×10 -4 mbar, a layer of aluminum was evaporated on the laser layer by a high vacuum aluminum coating machine with a thickness of

[0064] Comparative Example 3

[0065] Comparative Example 3 provides a method for preparing a transfer film having a cat's eye lens positioning pattern. The difference between Comparative Example 3 and Example 1 is that, on the PET base film, a second transfer coating coating is first applied, and then a first transfer coating coating is applied, which specifically includes the following steps:

[0066] (1) Preparation of PET transfer base film

[0067] Prepare a first-coat transfer coating and a second-coat transfer coating, wherein the first-coat transfer coating includes the following raw material components by weight percentage: 22% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 12% cellulose acetate, 22% ethyl acetate and 20% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use. The second-coat transfer coating includes the following raw material components by weight percentage: 18% acrylate copolymer, 12% cellulose acetate propionate, 12% cellulose acetate butyrate, 11% cellulose acetate, 21% ethyl acetate, 6% n-propyl acetate and 20% butanone. Mix the raw material components before coating, and then stir at a uniform speed of 2500rpm / min for 1.0h for standby use.

[0068] Take the PET base film, use a steel mesh roller with 150 mesh, and coat it at a coating speed of 105m / min and a drying efficiency of 85%. First, coat the second transfer coating, and control the dry coating amount of the second transfer coating to 1.2g / m 2 ; Then apply a transfer coating on the second transfer coating, and control the dry coating amount of the first transfer coating to 1.8g / m 2 ; Total dry coating weight 3.0g / m 2 , a PET transfer base film was obtained. During the coating process, the coating humidity was controlled at 60% and the temperature was controlled at 23°C.

[0069] (2) Hot pressing laser layer on the transfer coating on the PET transfer base film

[0070] The laser layer with the cat's eye positioning pattern laser effect on the nickel plate is molded and replicated onto the transfer coating of the PET transfer base film through a hot pressing process. During the molding process, the plate roller temperature is 188°C, the pressure of the roller is 40kg / cm, and the speed is 40m / min.

[0071] (3) Aluminum coating on the laser layer

[0072] Using 99.80% pure aluminum wire, the vacuum pressure is 6.2×10 -4mbar, a layer of aluminum was evaporated on the laser layer by a high vacuum aluminum coating machine with a thickness of

[0073] Product effect testing

[0074] (1) Appearance inspection

[0075] The transfer films with cat's eye lens positioning patterns prepared in Examples 1, 2 and Comparative Example 1 were inspected for appearance. Figure 1 , 2 The effect diagrams of the transfer film with cat's eye lens positioning pattern prepared in Example 1 and Comparative Example 1 are shown respectively. Figure 1 and Figure 2 It can be seen that the transfer films prepared in Example 1 and Comparative Example 1 have clear photolithography patterns and human shadow lenses, good lens restoration effects, and no scratches or white marks. It can be seen that the laser lens pattern of the transfer film prepared by hot pressing in the present invention can achieve the same lens effect as the transfer film prepared by UV process. Figure 4 , Figure 5 The following are partial effect diagrams of the transfer films with cat's eye lens positioning patterns prepared in Comparative Examples 2 and 3 respectively. Figure 4 It can be seen that directly coating the total dry weight at one time will result in poor leveling effect of the prepared transfer film, obvious scratch lines and blurring on the lens pattern, and poor lens restoration effect. Figure 5 It can be seen that after exchanging the order of the first transfer coating and the second transfer coating, the leveling effect of the transfer film is poor, there are obvious scratches and white marks on the lens pattern, and the lens restoration effect is poor.

[0076] (2) Folding resistance test

[0077] The transfer films with cat-eye lens positioning patterns prepared in Example 1 and Comparative Example 1 were transferred to 225g white cardboard, and the transfer ink layer was compared by synchronous bending using a folding resistance testing device. Figure 3 As shown, Figure 3 A in the figure is the effect picture after the transfer film of comparative example 1 is bent 4 times, where Figure 3 B is the effect diagram of the transfer film of Example 1 after being bent 6 times. Figure 3 It can be seen that the transfer film prepared in comparative example 1 showed obvious whitening after being bent 4 times after transfer, and the whitening phenomenon was more than that of the transfer film of example 1 after being bent 6 times. Example 2 had the same excellent folding resistance as example 1. It can be seen that the flexibility and folding resistance of the transfer film prepared in the example of the present invention are significantly better than the transfer film prepared by the UV process.

[0078] In addition, by comparing Example 1 of the present invention with Comparative Example 1, it can be seen that the present invention performs two coatings to achieve a dry coating weight of 2.8-3.0 g / m 2, so that the transfer coating has high film-forming properties and high flexibility. During molding (hot pressing), the original nickel cat-eye lens positioning pattern can be perfectly reproduced on the PET transfer base film under high temperature and high pressure conditions, and then a layer of aluminum is evaporated on its surface. The laser lens pattern effect after brightening by the aluminum layer can achieve the same lens effect as the UV process. The total dry coating amount in the UV process is 8-9g / m 2 The amount of coating used is 2.7-3.2 times that of the present application. The preparation method provided by the present invention can reduce the production material cost of UV transfer film by more than 60%.

[0079] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a transfer film having a cat's eye lens positioning pattern, characterized in that: The following steps are involved: preparing a first-coat transfer coating and a second-coat transfer coating; Take a PET base film, apply the first transfer coating paint and the second transfer coating paint in sequence to form a transfer coating layer to obtain a PET transfer base film; then heat-press a laser layer on the transfer coating layer of the PET transfer base film; finally, aluminum is plated on the laser layer to obtain a transfer film; The one-coat transfer coating comprises the following raw material components by weight percentage: 21%-25% acrylate copolymer, 10%-15% cellulose acetate propionate, 10%-15% cellulose acetate butyrate, 10%-15% cellulose acetate, 20%-25% ethyl acetate and 20%-28% butanone; The two-coat transfer coating comprises the following raw material components by weight percentage: 16%-20% acrylate copolymer, 10%-15% cellulose acetate propionate, 10%-15% cellulose acetate butyrate, 10%-15% cellulose acetate, 20%-25% ethyl acetate, 5%-10% n-propyl acetate and 20%-28% butanone.

2. The preparation method according to claim 1, characterized in that: The dry coating amount of the transfer coating formed by the transfer coating paint is 1.5-2.0g / m 2 The dry coating amount of the second transfer coating formed by the second transfer coating paint is 1.0-1.4g / m 2 .

3. The preparation method according to claim 2, characterized in that: The dry coating weight of the transfer coating formed by the transfer coating is 1.7-1.8 g / m 2 The dry coating amount of the second transfer coating formed by the second transfer coating paint is 1.1-1.2g / m 2 The total dry coating amount of the transfer coating is 2.8-3.0g / m 2 .

4. The preparation method according to any one of claims 1 to 3, characterized in that The preparation process of the first-coat transfer coating is: mixing the raw material components, and then stirring at a uniform speed of 2000-3000rpm / min for 0.5-1.0h; the preparation process of the second-coat transfer coating is: mixing the raw material components, and then stirring at a uniform speed of 2000-3000rpm / min for 0.5-1.0h.

5. The preparation method according to any one of claims 1 to 3, characterized in that: The coating is carried out by using a mesh roller, the mesh number of the mesh roller is 150-200 meshes; the coating speed is 100-110 m / min, and the drying efficiency is 83%-88%.

6. The preparation method according to claim 5, characterized in that: During the coating process, the humidity of the production environment is controlled to be 55%-65% and the temperature is controlled to be 19°C-25°C.

7. The preparation method according to any one of claims 1 to 3, characterized in that: The process of hot pressing the laser layer is: hot pressing is performed under the conditions of a plate roller temperature of 185-195° C., a roller pressure of 38-42 kg / cm, and a speed of 30-50 m / min.

8. The preparation method according to any one of claims 1 to 3, characterized in that: The aluminum plating process is as follows: using aluminum wire with a purity of more than 99.75% under a vacuum pressure of 6.0×10 -4 mbar or more, a high vacuum aluminum coating machine is used to evaporate the laser layer with a thickness of of aluminum layer.

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