UV medium transfer paper and preparation method thereof

Abstract

The invention provides a preparation method of UV medium transfer paper, and the preparation method comprises the following steps: providing a mother film which comprises a pre-coating film substrate and a UV laser chemical layer which are stacked and fixed; plating a dielectric layer on the surface, deviating from the pre-coating film substrate, of the UV laser chemical layer; forming a rotation assisting layer on the surface, deviating from the UV laser chemical layer, of the dielectric layer; forming a transfer adhesive layer on the surface, deviating from the dielectric layer, of the rotation assisting layer; forming a paper base material on the surface, deviating from the transfer assisting layer, of the transfer glue layer; and stripping the mother film to enable the dielectric layer to form a laser dielectric layer. According to the preparation method provided by the invention, the stripped mother film comprises the laser information layer and can be repeatedly used for multiple times, so that the production cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of packaging materials, and in particular to UV medium transfer paper and a preparation method thereof. Background Art

[0002] Currently, due to the limitations of the production process of microlens UV medium transfer paper in the packaging material field, the laser information layer of the mother film is peeled off together with the glue layer and bonded to the paper, resulting in the mother film being unable to preserve the laser information layer after one transfer, and thus causing the mother film to be unable to be reused, which will extend the production cycle of packaging materials and increase production costs. Summary of the invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing UV medium transfer paper. The preparation method provided in this application is conducive to shortening the production cycle to improve production efficiency. The peeled mother film (including the laser information layer) can be reused 5-10 times, thereby helping to reduce production costs.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0005] A method for preparing UV medium transfer paper comprises the following steps:

[0006] Providing a mother film, the mother film comprising a pre-coated film substrate and a UV laser chemical layer that are stacked and fixed;

[0007] Plating a dielectric layer on the surface of the UV laser chemical layer away from the pre-coated film substrate;

[0008] forming a rotation-assisting layer on a surface of the dielectric layer facing away from the UV laser chemical layer;

[0009] forming a transfer adhesive layer on the surface of the transfer-assisting layer away from the dielectric layer;

[0010] Forming a paper substrate on the surface of the transfer adhesive layer away from the transfer-assisting layer;

[0011] The mother film is peeled off so that the dielectric layer forms a laser dielectric layer.

[0012] In some possible embodiments, the preparation of the mother film includes:

[0013] Forming a UV coating layer on the surface of the pre-coated film substrate to obtain a first substrate, wherein the UV coating layer has a thickness of 6 μm to 10 μm, and the pre-coated film substrate has a thickness of 15 μm to 25 μm;

[0014] The first substrate is transferred to a UV molding machine for molding and curing, and is molded on a nickel plate with a pattern and then cured by an ultraviolet lamp, so that the UV coating layer forms the UV laser chemical layer. The curing irradiation power is 15-20KW to obtain a second substrate. The mesh number of the molding mesh roller is 150-200 meshes, the hardness of the molding oil pressure roller is 90-93HB, and the transmission speed of the second substrate is 30-50m / min.

[0015] In some possible implementations, the diffraction coefficient of the medium layer is 80%-90%.

[0016] In some possible implementations, the dry coating weight of the rotation-assisting layer is 1.15-1.25 g / m 2 .

[0017] In some possible implementations, the coating amount of the transfer adhesive layer is 5-7 g / m 2 .

[0018] In some possible implementations, the following further includes:

[0019] A varnish protective layer is formed at least on the surface of the laser medium layer away from the rotation-assisting layer, and the wet coating amount of the varnish protective layer is 3.0 g / m 2 -4.0g / m 2 .

[0020] In some possible implementations, the following further includes:

[0021] A back coating layer is formed at least on the surface of the paper substrate away from the transfer adhesive layer, and the coating amount of the back coating layer is 2.5-3.5 g / m 2 .

[0022] The present application also provides a UV medium transfer paper, including a paper substrate, and further comprising:

[0023] A transfer adhesive layer, bonded to a surface of the paper substrate;

[0024] A transfer-assisting layer, bonded to a surface of the transfer adhesive layer facing away from the paper substrate;

[0025] The laser medium layer is bonded to a surface of the transfer-assisting layer that is away from the transfer adhesive layer.

[0026] In some possible implementations, the following further includes:

[0027] The varnish protective layer at least covers the surface of the laser medium layer away from the rotation-assisting layer, and the wet coating amount of the varnish protective layer is 3.0 g / m 2 -4.0g / m 2 ;

[0028] The diffraction rate of the laser medium layer is 80%-90%, and the dry coating amount of the rotation-assisting layer is 1.15-1.25 g / m 2 The coating amount of the transfer adhesive layer is 5-7g / m 2 .

[0029] In some possible implementations, the following further includes:

[0030] The back coating layer is at least coated on the surface of the paper substrate away from the transfer adhesive layer, and the coating amount of the back coating layer is 2.5-3.5g / m 2 .

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] In the present application, the step of performing corona treatment on the UV laser chemical layer is omitted, thereby reducing the bonding force between the UV laser chemical layer and the dielectric layer. In addition, a stacked transfer-assisting layer and a transfer adhesive layer are sequentially formed on one side of the dielectric layer, so that the mother film retaining the laser information can be peeled off when the UV dielectric transfer paper is formed, so that the mother film can be reused multiple times, which is beneficial to shorten the production cycle of the packaging material to improve production efficiency, thereby helping to reduce production costs.

[0033] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A cross-sectional view of a mother film provided in one embodiment of the present application;

[0035] Figure 2 For Figure 1 A cross-sectional view of a dielectric layer formed by a mother film as shown;

[0036] Figure 3 For Figure 2 The dielectric layer shown forms a cross-sectional view of a rotation-assisting layer;

[0037] Figure 4 For Figure 3 The cross-sectional view of the transfer-assisting layer forming the transfer adhesive layer shown;

[0038] Figure 5 For Figure 4 The transfer adhesive layer shown forms a cross-sectional view of a paper substrate;

[0039] Figure 6 A cross-sectional view of forming a varnish protective layer on a laser medium layer;

[0040] Figure 7 For Figure 6 A cross-sectional view of a paper substrate forming a back coating is shown.

[0041] Description of Figure Numbers:

[0042] 100 - UV medium transfer paper; 10 - mother film; 11 - pre-coated film substrate; 12 - UV laser chemical layer; 20 - medium layer; 21 - laser medium layer; 30 - transfer-assisting layer; 40 - transfer adhesive layer; 50 - paper substrate; 60 - varnish protective layer; 70 - back coating. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there can be a centered element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be a centered element. When an element is referred to as "arranged on" another element, it can be arranged on the other element or there can be a centered element.

[0045] The present application provides a method for preparing UV medium transfer paper, comprising the following steps:

[0046] Step 1, refer to Figure 1 , providing a mother film 10, the mother film includes a stacked and fixed pre-coated film substrate 11 and a UV laser chemical layer 12. Exemplarily, the pre-coated film substrate 11 can be one of PET (polyethylene terephthalate) chemical pre-coated film, BOPP (biaxially oriented polypropylene) coating film, and PVC (polyvinyl chloride) coating film.

[0047] In some embodiments, the preparation of the mother film 10 comprises the following steps:

[0048] A UV coating layer is formed on one surface of the pre-coated film substrate 11 to obtain a first substrate. Exemplarily, the material of the UV coating layer can be UV varnish, and exemplary, it can be Zhisheng varnish. The thickness of the UV coating layer is 6μm-10μm, preferably, the thickness of the UV coating layer is about 8μm, and the standard is that the laser brightness of the microlens on the nickel plate can be clearly restored; the thickness of the pre-coated film substrate 11 is 15μm-25μm, preferably, the thickness of the pre-coated film substrate 11 is 15μm, and the substrate is as thin as possible to reduce production costs while meeting the microlens laser pattern overprinting standard.

[0049] The first substrate is transferred to a UV molding machine for molding and curing, so that the UV coating layer forms a UV laser chemical layer 12 to obtain a second substrate. Specifically, the first substrate is transferred to the laser transfer plate and the oil pressure roller in the UV molding machine for lamination, and the laser transfer plate covers the UV coating layer. For example, the laser nickel plate can be a nickel plate with a microlens laser pattern structure. The microlens laser pattern of the laser photolithography plate can be engraved according to the design drawings using a photolithography machine. Specifically, a laser holographic anti-counterfeiting platemaking device can be used to make a pattern with a microlens effect, and the plate can be made in combination with the drawings required by the customer, and a resin plate that can be used for electroforming can be made, and a nickel plate that can be used for UV molding can be made by the electroforming principle. It can be understood that the laser nickel plate can have other styles of laser patterns, thereby realizing the anti-counterfeiting function of different styles of transfer paper. The UV ultraviolet lamp irradiates the UV coating layer to cure it, and the curing irradiation power of the UV ultraviolet lamp is 15-20KW. The combination of the UV coating layer and the curing heat value is conducive to improving the curing rate.

[0050] The second substrate is conveyed to the mesh roller and the oil pressure roller for pressing to obtain the mother film 10. The mesh number of the mesh roller is 150-200 meshes, the hardness of the oil pressure roller is 90-93HB, and the conveying speed of the second substrate is 30-50m / min. The coordination of the mesh number, hardness and conveying speed is conducive to reducing the positioning pattern positioning error, and the positioning pattern positioning error can be within 0.1mm, which is conducive to ensuring the expected visual effect. The UV molding machine is a conventional equipment that can be purchased from the market, so its specific structure is not repeated.

[0051] In other embodiments, the purchased mother film 10 can be directly used for transfer work, or the above-mentioned process parameters can be changed.

[0052] Step 2, refer to Figure 2, a dielectric layer 20 is plated on the surface of the UV laser chemical layer 12 away from the pre-coated film substrate 11. For example, the material of the dielectric layer 20 can be zinc sulfide to achieve a transparent effect. In another embodiment, the material of the dielectric layer 20 can be aluminum. For example, the dielectric layer 20 can be deposited on the UV laser chemical layer 12 by vacuum evaporation using a zinc sulfide plating machine. The vacuum pressure of the vacuum evaporation is 8.0×10 －4 mbar.

[0053] In some embodiments, the diffraction rate of the dielectric layer 20 is 80%-90%. Preferably, the diffraction rate of the dielectric layer 20 is 85%-88%. Within this range, both the cost advantage and the laser light transmission effect of the microlens can be achieved.

[0054] Step 3, refer to Figure 3 A rotation-assisting layer is formed on the surface of the dielectric layer 20 away from the UV laser chemical layer 12. For example, the rotation-assisting layer is obtained by drying a water-based coating. The water-based coating may be composed of 91%-94% by weight of a water-based polyurethane resin and 6%-9% of a leveling agent, and the drying efficiency is 71-76°C.

[0055] Specifically, a rotation-assisting coating is formed on the surface of the dielectric layer 20 away from the UV laser chemical layer 12, and the rotation-assisting coating is cured to form the rotation-assisting layer 30. Exemplarily, the rotation-assisting coating can be dried at 71°C. Exemplarily, the rotation-assisting coating can be a reactive coating, so that the film-forming substance of the coating forms a network cross-linked structure after curing, thereby enhancing the connection strength between the rotation-assisting layer 30 and its adjacent layers, and further facilitating the peeling of the auxiliary dielectric layer 20 and the UV laser chemical layer 12. Exemplarily, the rotation-assisting coating can be applied by a common coating machine.

[0056] In some embodiments, the dry coating weight of the rotation-assisting layer 30 is 1.15-1.25 g / m 2 , within this range the integrity of the transfer can be guaranteed.

[0057] Step 4, refer to Figure 4 A transfer adhesive layer 40 is formed on the surface of the transfer-assisting layer 30 away from the dielectric layer 20. For example, the glue of the transfer adhesive layer 40 can be Xinbao transfer adhesive. For example, the transfer adhesive layer 40 can be selected from one of polyurethane transfer adhesive and acrylate transfer adhesive.

[0058] In some embodiments, the coating amount of the transfer adhesive layer 40 is 5-7 g / m 2 .

[0059] Step 5, refer to Figure 5A paper substrate 50 is formed on the surface of the transfer adhesive layer 40 away from the transfer-assisting layer 30. For example, the paper substrate 50 may be a general-purpose paper for packaging, such as kraft paper, white paper, corrugated paper, parchment paper, glassine paper, tar paper, and moisture-proof paper. For example, the thickness of the paper substrate 50 may be 100 μm-400 μm, such as 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, or a range between the above values.

[0060] Step 6, refer to Figure 5 and Figure 6 , peeling off the mother film 10, so that the dielectric layer 20 forms a laser dielectric layer 21. After peeling off the mother film 10, the dielectric layer 20 replicates the laser information of the UV laser chemical layer 12, so that the formed laser dielectric layer 21 can have a microlens laser anti-counterfeiting effect, and the mother film 10 can be reused. When reused, it is only necessary to repeat the steps of forming the dielectric layer 20, the transfer-assisting layer 30, the transfer adhesive layer 40, the paper substrate 50 and peeling. In this embodiment, the mother film 10 can be reused 5-10 times.

[0061] Step 6, refer to Figure 6 A varnish protective layer 60 is formed at least on the surface of the laser medium layer 21 away from the rotation-assisting layer 30, and the wet coating amount of the varnish protective layer 60 is 3.0 g / m 2 -4.0g / m 2 , for example, it can be 3.0g / m 2 , 3.1g / m 2 3.2g / m 2 3.3g / m 2 3.4g / m 2 3.5g / m 2 , or select an adaptation value between the above values. Further, the varnish protective layer 60 can be coated on the entire exposed surface of the laser medium layer 21. For example, the varnish protective layer 60 can be dried using process parameters of an oven temperature of 70-120°C and a conveying speed of 80-120m / min. The above process parameters for drying the varnish protective layer 60 are conducive to ensuring the flatness of the varnish protective layer 60 and to increasing the drying rate. The wet coating amount of the varnish protective layer 60 is conducive to ensuring that the laser effect of the laser medium layer 21 will not be destroyed by the varnish protective layer 60, such as the microlens effect of the laser, so that the protectiveness of the laser medium layer 21 can be improved while taking into account the laser effect, thereby helping to increase the service life. For example, the varnish protective layer 60 can be made of Huihua varnish.

[0062] Step 7, refer to Figure 7The back coating layer 70 is formed at least on the surface of the paper substrate 50 away from the transfer adhesive layer 40 to obtain the UV medium transfer paper 100. Furthermore, the back coating layer 70 can cover the entire exposed surface of the paper substrate 50. The coating amount of the back coating layer 70 is 2.5-3.5 g / m 2 For example, the coating amount can be 2.5 g / m 2 , 2.6g / m 2 , 2.7g / m 2 , 2.8g / m 2 , 2.9g / m 2 3.0g / m 2 , 3.1g / m 2 3.2g / m 2 3.3g / m 2 3.4g / m 2 3.5g / m 2 3.6g / m 2 , or select an adaptive value between the above values. Exemplarily, the back coating layer 70 can be formed by curing varnish, or can be formed by curing polyester material, acrylic material, or silicone material, so as to form a corresponding protective layer for the paper substrate 50, such as forming UV protection, waterproof protection, or abrasion protection. The material of the back coating layer 70 can be selected according to the corresponding protection requirements for the paper substrate 50.

[0063] In another embodiment, step six and step seven may be omitted.

[0064] In the present application, the step of performing corona treatment on the UV laser chemical layer 12 is omitted, thereby reducing the bonding force between the UV laser chemical layer 12 and the dielectric layer 20. In addition, a stacked transfer-assisting layer 30 and a transfer adhesive layer 40 are sequentially formed on one side of the dielectric layer 20, so that the mother film 10 retaining the laser information can be peeled off when the UV dielectric transfer paper 100 is formed, so that the mother film 10 can be repeatedly used multiple times, which is beneficial to shorten the production cycle of the packaging material to improve production efficiency, thereby helping to reduce production costs.

[0065] Reference Figure 7 Another embodiment of the present application provides a UV medium transfer paper 100, which can be obtained by the above-mentioned preparation method. The UV medium transfer paper 100 includes a paper substrate 50, a transfer adhesive layer 40, a transfer-assisting layer 30 and a laser medium layer 21. The transfer adhesive layer 40 is bonded to a surface of the paper substrate 50, the transfer-assisting layer 30 is bonded to a surface of the transfer adhesive layer 40 away from the paper substrate 50, and the laser medium layer 21 is bonded to a surface of the transfer adhesive layer 40 away from the transfer adhesive layer 40. Since the materials of each layer of the present application are the same as the materials of each layer in the above-mentioned preparation method, the materials of each layer will not be described in detail.

[0066] In some embodiments, the UV medium transfer paper 100 further includes a varnish protective layer 60, which at least covers the surface of the laser medium layer 21 away from the transfer-assisting layer 30. Furthermore, the varnish protective layer 60 can cover the entire exposed surface of the laser medium layer 21. The wet coating amount of the varnish protective layer 60 is 3.0 g / m 2 -4.0g / m 2 , for example, it can be 3.0g / m 2 , 3.1g / m 2 3.2g / m 2 3.3g / m 2 3.4g / m 2 3.5g / m 2 3.6g / m 2 3.7g / m 2 3.8g / m 2 3.8g / m 2 , 3.9g / m 2 4.0g / m 2 , or select an adaptation value between the above values. The diffraction coefficient of the laser medium layer 21 is 80-90%. Exemplarily, the diffraction coefficient of the laser medium layer 21 can be 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% and 90%, or select an adaptation value between the above values. In the present embodiment, the diffraction coefficient of the laser medium layer 21 is 86%. Preferably, the diffraction coefficient of the laser medium layer 21 is 85%-90%. The dry coating amount of the rotation-assisting layer 30 is 1.15-1.25g / m 2 The coating amount of the transfer adhesive layer 40 is 5-7 g / m 2 .

[0067] In some embodiments, the thickness of the paper substrate 50 may be 100 μm-400 μm, for example, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, or an adaptive value between the above values.

[0068] In some embodiments, the UV media transfer paper 100 further includes a back coating 70, which is coated on at least the surface of the paper substrate 50 away from the transfer adhesive layer 40. Furthermore, the back coating 70 may be coated on the entire exposed surface of the paper substrate 50. The coating amount of the back coating 70 is 2.5-3.5 g / m 2 For example, the coating amount can be 2.5 g / m 2 , 2.6g / m 2 , 2.7g / m 2 , 2.8g / m 2 , 2.9g / m 2 3.0g / m2 , 3.1g / m 2 3.2g / m 2 3.3g / m 2 3.4g / m 2 3.5g / m 2 , select an adaptation value between the above values.

[0069] The UV medium transfer paper 100 provided in the present application is suitable for exquisite anti-counterfeiting packaging of tobacco and alcohol, and can also be applied to the packaging of gifts, tea, cosmetics, food and medicine.

[0070] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for preparing UV medium transfer paper, characterized in that: The steps include: Providing a mother film, the mother film comprising a pre-coated film substrate and a UV laser chemical layer that are stacked and fixed; Plating a dielectric layer on the surface of the UV laser chemical layer away from the pre-coated film substrate; forming a rotation-assisting layer on a surface of the dielectric layer facing away from the UV laser chemical layer; forming a transfer adhesive layer on the surface of the transfer-assisting layer away from the dielectric layer; Forming a paper substrate on the surface of the transfer adhesive layer away from the transfer-assisting layer; The mother film is peeled off so that the dielectric layer forms a laser dielectric layer.

2. The preparation method according to claim 1, characterized in that The preparation of the mother film comprises: Forming a UV coating layer on one surface of the pre-coated film substrate to obtain a first substrate, wherein the UV coating layer has a thickness of 6 μm to 10 μm, and the pre-coated film substrate has a thickness of 15 μm to 25 μm; The first substrate is transferred to a UV molding machine for molding and curing, and is molded on a nickel plate with a pattern and then cured by an ultraviolet lamp, so that the UV coating layer forms the UV laser chemical layer. The curing irradiation power is 15-20KW to obtain a second substrate. The mesh number of the molding mesh roller is 150-200 meshes, the hardness of the molding oil pressure roller is 90-93HB, and the transmission speed of the second substrate is 30-50m / min.

3. The preparation method according to claim 1, characterized in that: The diffraction rate of the medium layer is 80%-90%.

4. The preparation method according to claim 1 or 3, characterized in that: The dry coating amount of the rotation-assisting layer is 1.15-1.25 g / m 2 .

5. The preparation method according to claim 4, characterized in that: The coating amount of the transfer adhesive layer is 5-7 g / m 2 .

6. The preparation method according to claim 1, characterized in that: Also includes: A varnish protective layer is formed at least on the surface of the laser medium layer away from the rotation-assisting layer, and the wet coating amount of the varnish protective layer is 3.0 g / m 2 -4.0g / m 2 .

7. The preparation method according to claim 6, characterized in that: Also includes: A back coating layer is formed at least on the surface of the paper substrate away from the transfer adhesive layer, and the coating amount of the back coating layer is 2.5-3.5 g / m 2 .

8. A UV medium transfer paper, comprising a paper substrate, characterized in that: Also includes: A transfer adhesive layer, bonded to a surface of the paper substrate; A transfer-assisting layer, bonded to a surface of the transfer adhesive layer facing away from the paper substrate; The laser medium layer is bonded to a surface of the transfer-assisting layer that is away from the transfer adhesive layer.

9. The UV medium transfer paper according to claim 8, characterized in that: Also includes: The varnish protective layer at least covers the surface of the laser medium layer away from the rotation-assisting layer, and the wet coating amount of the varnish protective layer is 3.0 g / m 2 -4.0g / m 2 ; The diffraction rate of the laser medium layer is 80%-90%, and the dry coating amount of the rotation-assisting layer is 1.15-1.25 g / m 2 The coating amount of the transfer adhesive layer is 5-7g / m 2 .

10. The UV medium transfer paper according to claim 9, characterized in that: Also includes: The back coating layer is at least coated on the surface of the paper substrate away from the transfer adhesive layer, and the coating amount of the back coating layer is 2.5-3.5g / m 2 .

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