A preparation process and product of vacuum aluminum-plated composite paper

Abstract

The present application relates to the field of environmentally friendly aluminum-coated packaging paper, and discloses a preparation process and product of vacuum aluminum-coated composite paper. A preparation process of vacuum aluminum-coated composite paper, comprising the following steps: S1, coating a base coating glue on a carrier film, and then pressing the base coating glue to the base paper; S2, tearing off the carrier film, and curing the base coating glue to form a base coating glue layer; S3, vacuum aluminum-coating the surface of the base coating glue layer to form an aluminum-coated layer; S4, coating a top coating glue on the side of the aluminum-coated layer away from the base coating glue layer, curing to form a top coating glue layer, and obtaining vacuum aluminum-coated composite paper; The preparation process of the present application is simple and easy to operate, first using a carrier film to transfer the base coating glue layer to the base paper, and then vacuum aluminum-coating the base coating glue layer after curing; The process has low requirements for the base paper, and the surface of the base coating glue layer after transfer is flat, which improves the uniformity and flatness of vacuum aluminum plating, and finally top coating is performed on the surface of the aluminum-coated layer, and the obtained vacuum aluminum-coated composite paper has a uniform texture, good folding resistance, and is not easy to burst.

Description

Technical Field

[0001] The present application relates to the field of environmentally friendly aluminized packaging paper, and more specifically, to a preparation process and product of vacuum aluminized composite paper. Background Art

[0002] Aluminized packaging paper is a packaging material that forms exquisite text and patterns on paper through vacuum aluminum plating. It has good metallic luster and decorative effect. It is used in product packaging to enhance the anti-counterfeiting and appearance texture of the packaged items.

[0003] Traditional aluminized packaging paper is generally vacuum-aluminized on the surface of BOPP or BOPET film, and then composited with paper using adhesive. This type of aluminized packaging paper contains plastic film and is less environmentally friendly. In order to improve the environmental friendliness of aluminized packaging paper, some people have proposed using vacuum aluminized composite paper to replace traditional aluminized packaging paper. Compared with traditional aluminized packaging paper, vacuum aluminized composite paper does not use plastic film and is more environmentally friendly.

[0004] Vacuum aluminized composite paper is generally prepared by transfer aluminizing or direct aluminizing. Transfer aluminizing is to first apply a layer of transfer coating on the BOPP or BOPET film, vacuum aluminize the surface of the transfer coating after curing, and then adhere the aluminized BOPP or BOPET film to the base paper through an adhesive. Finally, the BOPP or BOPET film is torn off, so that the aluminized layer with the transfer coating is attached to the base paper. Although the transfer aluminized composite paper prepared in this way has good environmental protection and good adhesion between the base paper and the aluminized layer, the scratch resistance of the aluminized layer is low, and it is easy to have creases or color bursting problems during use.

[0005] Direct aluminum plating is to apply a primer on the surface of the base paper, which forms a primer layer after solidification, and then vacuum aluminum is applied on the surface of the primer layer to form an aluminum layer, and finally a top coat is applied on the surface of the aluminum layer to form a top coat after solidification, thereby producing direct-plated composite paper. Although the process steps of direct aluminum plating are simple, the process of direct aluminum plating has high requirements for the base paper, and generally requires the use of special paper that has been flattened. It is less applicable to conventional base paper, which increases the production cost; and the primer is easily uneven during the coating process, thereby reducing the uniformity of the aluminum layer. Summary of the invention

[0006] In order to solve the problems of high production cost, low uniformity of aluminum coating layer, poor folding resistance and easy color fading of conventional vacuum aluminum-plated composite paper, the present application provides a preparation process and product of vacuum aluminum-plated composite paper.

[0007] In a first aspect, the present application provides a process for preparing vacuum aluminum-plated composite paper, which adopts the following technical solution:

[0008] A preparation process of vacuum aluminum-plated composite paper, comprising the following preparation steps:

[0009] S1, coating the base coating glue on the carrier film, and then pressing the base coating glue onto the base paper;

[0010] S2, tearing off the carrier film, curing the primer to form a primer layer;

[0011] S3, vacuum aluminum plating is performed on the surface of the primer layer to form an aluminum plating layer;

[0012] S4, applying a surface coating glue on the side of the aluminum-plated layer away from the base coating glue layer, curing to form a surface coating glue layer, and obtaining a vacuum aluminum-plated composite paper.

[0013] By adopting the above technical scheme, adhesive is first applied on the carrier film so that the primer adhesive is evenly leveled on the carrier film, and then pressed on the base paper to reduce the problem of uneven film formation when the primer adhesive contacts the base paper, and the leveled primer adhesive can evenly adhere to the surface of the base paper; then the carrier film is torn off, and under the film effect of the carrier film, the side of the primer adhesive away from the base paper has a flat and smooth adhesive surface, and then the primer adhesive is cured so that the primer adhesive forms a uniform and flat primer adhesive layer on the surface of the base paper, thereby improving the uniformity and flatness of subsequent vacuum aluminum plating; then the primer adhesive layer is vacuum aluminum-plated so that an aluminum-plated layer with uniform texture and metallic luster is formed on the surface of the primer adhesive layer, and finally the surface coating adhesive is applied on the surface of the aluminum-plated layer to improve the wear resistance and scratch resistance of the aluminum-plated layer, thereby preparing vacuum aluminum-plated composite paper.

[0014] The present application adopts a preparation process of transferring the primer coating by a carrier film, so that the primer coating is evenly and smoothly transferred to the base paper, and the requirements for the base paper are low. The base paper does not need to select special paper that has been flattened, the preparation cost is low, and the process applicability is wider; it solves the problem of uneven aluminum coating layer due to poor coating uniformity of the primer coating in the direct aluminum plating process, and the obtained vacuum aluminum-plated composite paper has good flatness and uniformity; the process of transferring the primer coating forms a soft and smooth primer coating layer on the surface of the base paper, which reduces the problem of easy color bursting of the aluminum plating layer in the conventional transfer aluminum plating process, and the obtained vacuum aluminum-plated composite paper has good folding resistance and is not easy to burst; in addition, the carrier film in the preparation process of the present application can be recycled, which reduces production energy consumption and saves waste materials; from the above, it can be seen that the preparation process of the vacuum aluminum-plated composite paper of the present application is simple in procedure, saves production cost, is suitable for preparing aluminum-plated packaging paper with uniform texture, good flatness, good folding resistance and not easy to burst color.

[0015] Preferably, in step S1, the coating amount of the primer is 30-40 g / m 2 , the pressing pressure is 0.1-0.3KPa.

[0016] By adopting the above technical solution, when the amount of primer coating is too small, although the uniformity of the primer coating will be better when applied to the supporting film, due to the unevenness of the surface of the base paper, the primer coating will partially penetrate into the base paper during the transfer process. Therefore, the less primer coating has a lower flatness on the surface of the base paper, and when the amount of primer coating is small, the softness of the vacuum aluminum-plated composite paper obtained will be low, and the aluminum-plated layer formed after aluminum plating is not foldable and easy to burst; and when the amount of primer coating is too much, it is easy to overflow glue during the lamination process with the base paper, and after the supporting film is torn off, the primer coating applied to the base paper will have uneven leveling. Therefore, the preparation process of the present application needs to control the coating amount of the better primer coating and the pressure during lamination to reduce the problem of uneven leveling when the primer coating is transferred to the base paper, and improve the flatness and uniformity of aluminum plating.

[0017] Preferably, the thickness of the aluminum plating layer in step S3 is 15-25 nm.

[0018] By adopting the above technical solution, the aluminum-plated layer is controlled within an optimal thickness range, so that the vacuum aluminum-plated composite paper has a uniform metallic luster texture, good folding resistance, and is not easy to burst color.

[0019] Preferably, in the step S2, before the carrier film is torn off, the side of the primer close to the carrier film is heat-set, the heat-setting temperature is 120-140° C., and the heat-setting time is 3-6 seconds.

[0020] By adopting the above technical scheme, in order to further improve the uniformity and smoothness of the primer transfer, the primer on the side close to the carrier film is firstly shaped using better curing conditions, while the primer on the side away from the carrier film can maintain good adhesion and can stably adhere to the surface of the base paper. After the carrier film is torn off, the primer on the side close to the carrier film is initially shaped, thereby reducing the extension of the primer or uneven leveling, thereby improving the uniformity and smoothness of the aluminum plating.

[0021] Preferably, the primer is made from the following raw materials in parts by weight:

[0022] Waterborne polyurethane modified acrylate emulsion 20-30%

[0023] Water-based hydroxy acrylic emulsion 10-15%

[0024] Tackifier 3-5%

[0025] Crosslinking agent 4-8%

[0026] Leveling agent 2-4%

[0027] Curing agent 1-2%

[0028] Water balance.

[0029] By adopting the above-mentioned technical scheme, in order to further solve the folding resistance and color popping problems of vacuum aluminum-plated composite paper, when the amount of primer is large, the primer will have uneven leveling problems during the transfer process, thereby reducing the uniformity and flatness of aluminum plating. Therefore, this application further studies the primer.

[0030] The water-based polyurethane modified acrylate emulsion has good flexibility and can improve the bending resistance of the prepared primer. However, the ductility of the water-based polyurethane modified acrylate emulsion is relatively large. When the primer is thicker, the leveling uniformity of the primer will be reduced. Therefore, it is compounded with the water-based hydroxyl acrylic emulsion. The water-based hydroxyl acrylic emulsion can improve the ductility of the water-based polyurethane modified acrylate emulsion, so that the prepared primer has good flexibility and moderate support, viscosity and ductility, reducing the occurrence of uneven leveling; the tackifier plays a good role in improving the cohesion and ductility of the prepared primer, making the primer It has good bonding stability while maintaining uniform leveling. After the carrier film is transferred, the thicker primer can maintain good flatness, reduce the uneven re-leveling of the primer on the surface of the base paper, and improve the flatness and uniformity of the cured primer layer. The cross-linking agent and the leveling agent can be further cross-linked and cured with the water-based polyurethane modified acrylate emulsion and the water-based acrylic emulsion under the curing action of the curing agent. Under the synergistic action of the tackifier, the cured primer layer has good flexibility and flatness, which improves the flatness and uniformity of the aluminum plating. The vacuum aluminum-plated composite paper obtained has a uniform texture, good folding resistance and is not easy to burst.

[0031] Preferably, the tackifier is prepared from the following raw materials in parts by weight:

[0032] 2-4 parts of methyl vinyl ether-maleic anhydride copolymer

[0033] Xanthan gum 0.5-1.5 parts

[0034] 4-6 parts of polyethylene glycol

[0035] 20-30 parts water;

[0036] The polyethylene glycol is any one of polyethylene glycol 200, polyethylene glycol 400 and polyethylene glycol 600.

[0037] By adopting the above technical scheme, the present application uses methyl vinyl ether-maleic anhydride copolymer and xanthan gum as the main thickener, which has a good synergistic effect. When dispersed in water, a three-dimensional network structure is formed, so that the emulsion system is evenly dispersed in the three-dimensional network structure, so as to improve the ductility, film-forming property and good viscosity of the primer, so that the primer has good leveling uniformity when coated on the carrier film, and the transferred primer can maintain good flatness and flexibility while stably adhering to the base paper, thereby improving the curing uniformity of the primer, and then improving the flatness and uniformity of aluminum plating, and then improving the folding resistance of the obtained vacuum aluminum-plated composite paper; when xanthan gum is dissolved in water, it will easily agglomerate, so polyethylene glycol is added to disperse the xanthan gum, improve the dissolution and dispersion uniformity of the thickener system, and reduce the problem of reduced uniformity of the primer due to uneven dispersion of the thickener; the thickener of the present application has good viscosity adjustment performance, and a smaller amount can achieve a better thickening effect.

[0038] Preferably, the tackifier is prepared by the following steps:

[0039] Add polyethylene glycol to water and stir evenly; add xanthan gum, raise the temperature to 40-50° C. to disperse and dissolve, and then add methyl vinyl ether-maleic anhydride copolymer to disperse and dissolve to prepare a thickener.

[0040] By adopting the above technical scheme, xanthan gum is first dissolved in water containing polyethylene glycol to form a uniform viscous system, and then methyl vinyl ether-maleic anhydride copolymer is added for uniform dispersion to form a thickener with a three-dimensional interwoven network molecular structure.

[0041] Preferably, the crosslinking agent is composed of glycidyl methacrylate and polydipentaerythritol hexaacrylate in a weight ratio of 1:(1-3).

[0042] By adopting the above technical scheme, glycidyl methacrylate and polydipentaerythritol hexaacrylate in an optimal dosage ratio are used as cross-linking agents, which can be cross-linked with the emulsion system to form a dispersed network structure system with large branched chain segments. The prepared primer has good adhesion and leveling uniformity as well as good flexibility. The flat surface after the carrier film is transferred can maintain good flatness, thereby improving the uniformity and flatness of aluminum plating, thereby improving the folding resistance of the obtained vacuum aluminum-plated composite paper and preventing color bursting.

[0043] Preferably, the leveling agent is composed of a vinyl dimethyl terminated vinyl methyl-dimethyl polysiloxane copolymer and propylene glycol block polyether in a weight ratio of 1:(0.2-0.4).

[0044] By adopting the above-mentioned technical scheme, the present application uses a vinyl dimethyl-terminated vinyl methyl-dimethylpolysiloxane copolymer and propylene glycol block polyether in an optimal dosage ratio as a leveling agent, which can better improve the leveling uniformity of the primer coating. At the same time, the vinyl dimethyl-terminated vinyl methyl-dimethylpolysiloxane copolymer can be further cross-linked with the emulsion system, so that the transferred primer coating layer can maintain good surface flatness and flexibility, thereby improving the flatness and folding resistance of the obtained vacuum aluminum-plated composite paper.

[0045] Preferably, the curing agent is any one of an isocyanate curing agent and an aziridine cross-linking agent.

[0046] By adopting the above technical scheme, the above curing agent can make the water-based polyurethane modified acrylate emulsion, water-based hydroxy acrylic emulsion and cross-linking agent stably cross-linked to form a stable three-dimensional cross-linked network structure, thereby enhancing the cohesion of the primer, improving the viscosity and fluidity of the primer, and thus improving the bonding stability and leveling uniformity of the primer.

[0047] In a second aspect, the present application provides a vacuum aluminum-plated composite paper, which adopts the following technical solution:

[0048] A vacuum aluminum-plated composite paper is prepared by the above-mentioned preparation process of the vacuum aluminum-plated composite paper.

[0049] By adopting the above technical solution, the vacuum aluminum-plated composite paper of the present application has a uniform aluminum-plated texture, good folding resistance and is not easy to burst color, and is suitable for the packaging of some high-end and exquisite items.

[0050] In summary, this application has the following beneficial effects:

[0051] 1. The preparation process of the vacuum aluminum-plated composite paper of the present application transfers the primer adhesive through a carrier film, so that the primer adhesive is evenly and smoothly transferred to the base paper, and the requirements for the base paper are low. The base paper does not need to select special paper that has been flattened, the preparation cost is low, and the process applicability is wider; it solves the problem of uneven aluminum coating due to poor coating uniformity of the primer adhesive in the direct aluminum plating process, and the obtained vacuum aluminum-plated composite paper has good flatness and uniformity; the process of transferring the primer adhesive forms a soft and smooth primer adhesive layer on the surface of the base paper, which reduces the problem of easy color bursting of the aluminum plating layer in the conventional transfer aluminum plating process, and the obtained vacuum aluminum-plated composite paper has good folding resistance and is not easy to burst; the preparation process of the vacuum aluminum-plated composite paper of the present application is simple in process, saves production cost, is suitable for preparing aluminum-plated packaging paper with uniform texture, good flatness, good folding resistance and not easy to burst.

[0052] 2. The present application uses a primer made of water-based polyurethane modified acrylic ester emulsion, water-based hydroxy acrylic emulsion, tackifier, cross-linking agent, leveling agent, curing agent and water. The prepared primer has moderate viscosity, good cohesion, flexibility and leveling uniformity. When the prepared primer is used in a large amount, the primer has good bonding stability while having uniform leveling. After being transferred through the carrier film, it can maintain good flatness, reduce the uneven leveling of the primer on the surface of the base paper, and improve the flatness and uniformity of the cured primer layer. The vacuum aluminum-plated composite paper prepared in this way has good flatness, flexibility and folding resistance, and is not easy to burst color.

[0053] 3. In the present application, methyl vinyl ether-maleic anhydride copolymer, xanthan gum and polyethylene glycol are compounded as thickeners, glycidyl methacrylate and polydipentaerythritol hexaacrylate are compounded as cross-linking agents, vinyl dimethyl-terminated vinyl methyl-dimethylpolysiloxane copolymer and propylene glycol block polyether are compounded as leveling agents. Under the synergistic effect of the thickener, cross-linking agent and leveling agent, water-based polyurethane-modified acrylate emulsion and water-based hydroxy acrylic emulsion are used as the emulsion system to further improve the adhesion, cohesion, flexibility and leveling uniformity of the prepared primer. DETAILED DESCRIPTION

[0054] The present application is further described in detail below with reference to the embodiments.

[0055] The following are the sources and specifications of some raw materials of this application. The raw materials used in the preparation examples and embodiments of this application can be obtained from the market, including but not limited to the raw materials of the following models and manufacturers. Raw materials with equivalent performance can be used:

[0056] 1. Waterborne polyurethane modified acrylate emulsion: Yierfu Chemical, EV-6154, solid content 40%;

[0057] 2. Water-based hydroxy acrylic emulsion: Lanbo LB-6019, solid content 40%;

[0058] 3. Methyl vinyl ether-maleic anhydride copolymer: Nona, CAS No. 9011-16-9, content 98-99%;

[0059] 4. Xanthan gum: Fufeng, 200 mesh;

[0060] 5. Polydipentaerythritol hexaacrylate: CAS No. 29570-58-9, density 1.184±0.06g / cm 3 ;

[0061] 6. Vinyl dimethyl terminated vinyl methyl-dimethyl polysiloxane copolymer: Nanjing Sisibo, SiSiBVF6060; 7. Propylene glycol block polyether: L62;

[0062] 8. Isocyanate curing agent: Covestro Z4470MPA / X;

[0063] 9. Aziridine crosslinker: Crosslinker CX-100;

[0064] 10. Carrier film: BOPET release film: thickness 25-50μm, peeling force 5-15g / in; BOPP release film: thickness 25-50μm, peeling force 5-15g / in;

[0065] 11. Base paper: The base paper is made of pure wood pulp but has not been smoothed. The moisture content of the base paper is 4-6%, and the smoothness of the base paper is 40-80s.

[0066] Preparation Example of Thickener

[0067] Preparation Example 1

[0068] Preparation Example 1 discloses a tackifier, which is prepared by the following steps:

[0069] 0.4 kg of polyethylene glycol 200 was added to 2 kg of water and stirred evenly; 0.05 kg of xanthan gum was added and the temperature was raised to 40° C. for dispersion and dissolution; then 0.4 kg of methyl vinyl ether-maleic anhydride copolymer was added and the dispersion and dissolution were carried out at a stirring rate of 500 r / min to prepare a thickener.

[0070] Preparation Example 2-3

[0071] The difference between Preparation Example 2-3 and Preparation Example 1 is that the amount of raw materials used and the preparation conditions are different, see Table 1 below for details.

[0072] Table 1 Raw material dosage and preparation conditions of Preparation Examples 1-3

[0073]

[0074]

[0075] Preparation Example 4

[0076] The difference between Preparation Example 4 and Preparation Example 1 is that an equal amount of xanthan gum is replaced by hydroxyethyl cellulose, Dow, HECQP-4400H, and the rest is the same as Preparation Example 1.

[0077] Preparation Example 5

[0078] The difference between Preparation Example 5 and Preparation Example 1 is that the methyl vinyl ether-maleic anhydride copolymer is replaced by polyvinyl alcohol, PVA2099 in equal amounts, and the rest is the same as Preparation Example 1.

[0079] Preparation Example 6

[0080] The difference between Preparation Example 6 and Preparation Example 1 is that an equal amount of methyl vinyl ether-maleic anhydride copolymer is replaced with xanthan gum, and the rest is the same as Preparation Example 1.

[0081] Preparation example of primer

[0082] Preparation Example 7

[0083] Preparation Example 7 discloses a primer, which is prepared by the following steps:

[0084] 2 kg of aqueous polyurethane modified acrylate emulsion, 1.5 kg of aqueous hydroxy acrylic emulsion, 0.4 kg of cross-linking agent (composed of glycidyl methacrylate and 4-hydroxybutyl acrylate in a weight ratio of 1:1) and 0.4 kg of leveling agent (composed of propylene glycol block polyether and dimethyl silicone oil in a weight ratio of 2:1) were added to 5.1 kg of water and stirred evenly. Then, 0.5 kg of the tackifier prepared in Preparation Example 1 and 0.1 kg of isocyanate curing agent were added and stirred evenly to prepare a primer.

[0085] Preparation Example 8-9

[0086] The difference between Preparation Example 8-9 and Preparation Example 7 is that the amount of raw materials used and the preparation conditions are different, see Table 2 below for details.

[0087] Table 2 Raw material dosage and preparation conditions of Preparation Examples 7-9

[0088]

[0089]

[0090] Preparation Example 10-12

[0091] The difference between Preparation Examples 10-12 and Preparation Example 7 is that the sources of the tackifiers are different, see Table 3 below for details.

[0092] Table 3 Sources of the tackifiers of Preparation Examples 10-12

[0093] Preparation Example Source of Thickener Preparation Example 10 Preparation Example 4 Preparation Example 11 Preparation Example 5 Preparation Example 12 Preparation Example 6

[0094] Preparation Example 13

[0095] The difference between Preparation Example 13 and Preparation Example 7 is that the cross-linking agent is different. The cross-linking agent in Preparation Example 13 is composed of glycidyl methacrylate and polydipentaerythritol hexaacrylate. The amount of glycidyl methacrylate is 0.2 kg, and the amount of polydipentaerythritol hexaacrylate is 0.2 kg. The rest is the same as Preparation Example 7.

[0096] Preparation Example 14

[0097] The difference between Preparation Example 14 and Preparation Example 13 is that the amount of glycidyl methacrylate used is 0.1 kg, the amount of polydipentaerythritol hexaacrylate used is 0.3 kg, and the rest is the same as Preparation Example 13.

[0098] Preparation Example 15

[0099] The difference between Preparation Example 15 and Preparation Example 13 is that the leveling agent is different. The leveling agent is composed of a vinyl dimethyl-terminated vinyl methyl-dimethylpolysiloxane copolymer and propylene glycol block polyether. The amount of the vinyl dimethyl-terminated vinyl methyl-dimethylpolysiloxane copolymer is 0.33 kg, and the amount of propylene glycol block polyether is 0.07 kg. The rest is the same as Preparation Example 13.

[0100] Preparation Example 16

[0101] The difference between Preparation Example 16 and Preparation Example 15 is that the amount of vinyl dimethyl-terminated vinyl methyl-dimethyl polysiloxane copolymer used is 0.285 kg, the amount of propylene glycol block polyether used is 0.115 kg, and the rest is the same as Preparation Example 15.

[0102] Preparation Example 17

[0103] The difference between Preparation Example 17 and Preparation Example 16 is that the vinyl dimethyl-terminated vinyl methyl-dimethyl polysiloxane copolymer is replaced by an equal amount of vinyl trimethoxy silane, and the rest is the same as Preparation Example 16.

[0104] Example

[0105] Example 1

[0106] Example 1 discloses a process for preparing vacuum aluminum-plated composite paper, comprising the following steps:

[0107] S1, using BOPET release film as the carrier film, on the carrier film at 30g / m 2 The commercially available primer was applied at a coating amount of 1000 g / m2, and then the primer was pressed at a pressure of 0.3 KPa to a gram weight of 50 g / m2. 2 On the backing paper;

[0108] S2, tearing off the carrier film, curing the primer at a temperature of 70°C for 15 minutes, and forming a primer layer on the surface of the base paper;

[0109] S3, using a vacuum aluminum plating machine to vacuum aluminum-plated on the surface of the primer layer, the aluminum plating thickness is 15nm, and an aluminum plating layer is formed on the surface of the primer layer;

[0110] S4, on the side of the aluminum coating away from the primer layer, 1g / m 2 A coating amount of commercially available top coating glue was applied, and the top coating glue layer was formed on the surface of the aluminum-plated layer at 70° C. to prepare a vacuum aluminum-plated composite paper;

[0111] The commercially available primer and topcoat are both Jilong brand, water-based acrylic emulsion CTD-6070.

[0112] Example 2-3

[0113] The difference between Example 2-3 and Example 1 is that, in step S2, before the carrier film is torn off, the side of the primer close to the carrier film is preliminarily thermally cured. For specific preparation processes and parameters, see Table 4 below.

[0114] Table 4 Preparation process and parameter table of Examples 1-3

[0115]

[0116] Embodiment 4-15

[0117] The difference between Example 4-14 and Example 1 is that the source of the primer is different, see Table 5 below for details.

[0118] Table 5 Sources of the primers of Examples 4-14

[0119]

[0120]

[0121] Embodiment 15

[0122] The difference between Example 15 and Example 1 is that the coating amount of the primer is 50 g / m 2 , the rest is the same as Example 1.

[0123] Example 16

[0124] The difference between Example 16 and Example 4 is that the coating amount of the primer is 50 g / m 2 , the rest is the same as Example 4.

[0125] Comparative Example

[0126] Comparative Example 1

[0127] The difference between Comparative Example 1 and Example 1 is that the BOPET film is first coated with 10 g / m 2 The commercially available primer was coated with a coating amount of 100 g / m2 and cured at 70°C for 10 min. After curing, vacuum aluminum was plated on the surface of the primer layer to form an aluminum layer with a thickness of 15 nm. Then, a 30 g / m2 aluminum layer was coated on the base paper. 2 A coating amount of commercially available primer was applied, and the BOPET film coated with an aluminized layer was laminated to the base paper through the primer. The laminating pressure was 0.1 KPa. After lamination, the film was cured at a temperature of 70°C for 15 minutes, and finally the BOPET film was torn off to obtain a vacuum aluminized composite paper.

[0128] Performance Testing The following performance tests were conducted on the vacuum aluminum-plated composite papers prepared in Examples 1-16 and Comparative Example 1:

[0129] 1. Aluminum plating flatness test:

[0130] According to the test method in BB / T 0054-2010 vacuum aluminum-plated paper, the flatness (unit: mm) of the vacuum aluminum-plated composite paper (uncoated surface glued) after aluminum plating is tested, and the test results are recorded;

[0131] 2. Aluminum plating uniformity test:

[0132] According to the test method in BB / T 0054-2010 vacuum aluminum-plated paper, the vacuum aluminum-plated composite paper (uncoated surface glued) after aluminum plating is tested for color difference ΔE, and the test results are recorded;

[0133] 3. Aluminum coating adhesion test:

[0134] According to the test method of vacuum aluminum-plated paper in BB / T 0054-2010, the aluminum-plated vacuum aluminum-plated composite paper (uncoated surface) is tested for the adhesion of the aluminum-plated layer (unit: %), and the test results are recorded;

[0135] 4. Folding resistance test of vacuum aluminized paper:

[0136] Refer to the test method in GB / T 457-2008 Determination of folding endurance of paper and paperboard, use MIT folding endurance tester to test the folding endurance of vacuum aluminized paper. When the vacuum aluminized composite paper bursts, stop the test, test and record the number of folding endurance (unit: times);

[0137] The following are the performance test data of the vacuum aluminum-plated composite paper of Examples 1-16 and Comparative Example 1, see Table 6 below for details.

[0138] Table 6 Performance data of vacuum aluminum-plated composite paper of Examples 1-16 and Comparative Example 1

[0139]

[0140] It can be concluded from Example 1 and Comparative Example 1 that the vacuum aluminum-plated composite paper prepared by the preparation process of the present application has good folding resistance and is not prone to color bursting.

[0141] Combining Example 1 with Examples 2-3, it can be concluded that before tearing off the carrier film, the side of the primer close to the carrier film is preliminarily shaped to improve the flatness and uniformity of the aluminum plating, thereby improving the folding resistance of the vacuum aluminum-plated composite paper.

[0142] Combining Example 1 and Examples 4-9, it can be concluded that the use of a primer made of a tackifier composed of methyl vinyl ether-maleic anhydride copolymer, xanthan gum and polyethylene glycol as a connector between the base paper and the aluminum-plated layer can significantly improve the flatness and uniformity of the aluminum plating. Compared with Example 1, the flatness of the aluminum-plated layer in Examples 4-6 is improved by 2.4 mm, the color difference is reduced by 1.6, and the adhesion is improved by 6.1%. The folding times of the vacuum aluminum-plated composite paper obtained are increased by 85 times, and the color bursting problem is significantly improved; and compared with Example 4, Examples 7-9 do not use methyl vinyl ether-maleic anhydride copolymer, xanthan gum and polyethylene glycol for compounding as a tackifier, the flatness and uniformity of the aluminum plating are low, and the adhesion of the aluminum-plated layer is reduced, and the folding times of the vacuum aluminum-plated composite paper obtained are also reduced.

[0143] In combination with Example 4 and Examples 10-14, it can be concluded that the use of glycidyl methacrylate and polydipentaerythritol hexaacrylate in a preferred dosage ratio of the present application as a cross-linking agent, and the use of a vinyl methyl-dimethyl polysiloxane copolymer terminated with vinyl dimethyl and propylene glycol block polyether in a preferred weight ratio as a leveling agent, produces a better synergistic effect, can better improve the flatness and uniformity of aluminum plating, the flatness can reach 0.5mm, the color difference is reduced to 0.2, the adhesion is increased to 99.8%, and the vacuum aluminum-plated composite paper obtained has a folding endurance of 333 times, which significantly improves the color burst problem.

[0144] Further, in combination with Example 1, Example 4, and Examples 15-16, it can be concluded that, compared with Example 1, the amount of primer is increased in Example 15, and the flatness and uniformity of aluminum plating are significantly reduced. This may be because the commercially available primer has a low leveling uniformity, which reduces the uniformity and flatness of the primer layer, and further reduces the flatness and uniformity of the aluminum plating layer; and compared with Example 4, the flatness and uniformity of the aluminum plating layer in Example 16 do not change much, which may be because the primer of the present application is used as the primer layer, and the leveling uniformity is good. Therefore, the flatness and uniformity of the aluminum plating layer change little, and the adhesion of the aluminum plating layer is also relatively stable. The thicker primer layer has better flexibility, and the folding resistance of the vacuum aluminum-plated composite paper obtained is slightly improved. This shows that the primer of the present application has good leveling uniformity and flexibility, and can significantly improve the flatness, flexibility and folding resistance of the vacuum aluminum-plated composite paper obtained.

[0145] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A process for preparing vacuum aluminum-plated composite paper, characterized in that: The method comprises the following preparation steps: S1, coating the primer on the carrier film, and then pressing the primer onto the base paper; S2, tearing off the carrier film, curing the primer to form a primer layer; S3, vacuum aluminum plating is performed on the surface of the primer layer to form an aluminum plating layer; S4, applying a top coating glue on the side of the aluminum coating layer away from the base coating layer, curing to form a top coating glue layer, and obtaining a vacuum aluminum-coated composite paper; In the step S1, the coating amount of the primer is 30-40 g / m 2 , the pressing pressure is 0.1-0.3KPa; The primer is prepared from the following raw materials in parts by weight: Waterborne polyurethane modified acrylate emulsion 20-30% Water-based hydroxy acrylic emulsion 10-15% Thickener 3-5% Crosslinking agent 4-8% Leveling agent 2-4% Curing agent 1-2% Water balance; The tackifier is prepared from the following raw materials in parts by weight: 2-4 parts of methyl vinyl ether-maleic anhydride copolymer Xanthan gum 0.5-1.5 parts 4-6 parts of polyethylene glycol 20-30 parts water; The crosslinking agent is composed of glycidyl methacrylate and polydipentaerythritol hexaacrylate in a weight ratio of 1:(1-3); The leveling agent is composed of a vinyl dimethyl terminated vinyl methyl-dimethyl polysiloxane copolymer and propylene glycol block polyether in a weight ratio of 1:(0.2-0.4).

2. The process for preparing vacuum aluminum-plated composite paper according to claim 1, characterized in that: In the step S2, before the carrier film is torn off, the side of the primer close to the carrier film is heat-set, the heat-setting temperature is 120-140° C., and the heat-setting time is 3-6 seconds.

3. The process for preparing vacuum aluminum-plated composite paper according to claim 1, characterized in that: The polyethylene glycol is any one of polyethylene glycol 200, polyethylene glycol 400 and polyethylene glycol 800.

4. The process for preparing vacuum aluminum-plated composite paper according to claim 1, characterized in that: The tackifier is prepared by the following steps: Add polyethylene glycol to water and stir evenly; add xanthan gum, raise the temperature to 40-50° C. to disperse and dissolve, and then add methyl vinyl ether-maleic anhydride copolymer to disperse and dissolve to prepare a thickener.

5. The process for preparing vacuum aluminum-plated composite paper according to claim 1, characterized in that: The curing agent is any one of an isocyanate curing agent and an aziridine cross-linking agent.

6. A vacuum aluminum-plated composite paper, characterized in that: The vacuum aluminum-plated composite paper is prepared by the preparation process of the vacuum aluminum-plated composite paper according to any one of claims 1 to 5.

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