High-temperature-resistant and solvent-resistant adhesive, PC anti-counterfeiting film and preparation method of PC anti-counterfeiting film

Abstract

The invention provides a high-temperature-resistant solvent-resistant adhesive, a PC (polycarbonate) anti-counterfeiting film and a preparation method of the high-temperature-resistant solvent-resistant adhesive. The high-temperature-resistant solvent-resistant adhesive is prepared from the following raw materials in parts by weight: 40-80 parts of acrylic resin, 20-60 parts of modified polyacrylic resin, 20-60 parts of modified amino resin, 10-20 parts of a first organic molecular monomer, 10-20 parts of a second organic molecular monomer, 3-5 parts of inorganic filler and 60-160 parts of a solvent. The preparation method comprises the following steps: sequentially adding acrylic resin, modified polyacrylic resin and modified amino resin into a solvent in which a monomer capable of self-polymerization reaction and an alcohol amine organic molecular monomer are dissolved, blending and filtering to prepare the high-temperature-resistant solvent-resistant adhesive, and the adhesive can not yellow under the action of high temperature, and can be cured after being soaked in a chemical solvent for a long time. According to the present invention, the adhesive has characteristics of excellent adhesion with the PC base material, good adhesion with the medium, good weather resistance and good aging resistance.

Description

Technical Field

[0001] The invention relates to the technical field of anti-counterfeiting films, and in particular to a high-temperature and solvent-resistant adhesive, a PC anti-counterfeiting film and a preparation method thereof. Background Art

[0002] With the rapid development and popularization of financial technology, financial cards with high security requirements have received widespread attention. Compared with traditional polyvinyl chloride (PVC) cards, polycarbonate (PC) cards are widely used in the field of financial cards due to their high strength, wear resistance, weather resistance, corrosion resistance, transparency and good gloss. At the same time, their easy degradation after disposal is more in line with the requirements of environmental protection and sustainable development.

[0003] At present, the common anti-counterfeiting method for financial cards is to laminate a holographic anti-counterfeiting layer inside the PC card and print on the holographic anti-counterfeiting layer to ensure the anti-counterfeiting strength and aesthetics of the PC card. However, due to the special processing technology of PC cards, they need to be laminated with multiple layers of PC films at high temperatures, so there are higher requirements for the temperature resistance of the holographic anti-counterfeiting layer sandwiched therein.

[0004] In addition, since PC cards need to be printed on the holographic anti-counterfeiting layer, the holographic anti-counterfeiting layer needs to have good solvent resistance to avoid the risk of delamination.

[0005] Based on this, the present invention proposes a new high temperature and solvent resistant adhesive, a PC anti-counterfeiting film and a corresponding preparation method. Summary of the invention

[0006] Based on the above description, the present invention provides a high temperature and solvent resistant adhesive, a PC anti-counterfeiting film and a preparation method thereof, so that the adhesive has good high temperature and solvent resistance and has good adhesion to the PC substrate and medium, thereby making the anti-counterfeiting film more firm and beautiful.

[0007] The technical solution of the present invention to solve the above technical problems is as follows: In a first aspect, the present invention provides a high temperature resistant and solvent resistant adhesive, comprising the following raw materials in parts by weight: 40 to 80 parts of acrylic resin, 20 to 60 parts of modified polyacrylic resin, 20 to 60 parts of modified amino resin, 10 to 20 parts of a first organic molecular monomer, 10 to 20 parts of a second organic molecular monomer, 3 to 5 parts of an inorganic filler, and 60 to 160 parts of a solvent.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Further, the monomers of the acrylic resin include methyl acrylate, butyl acrylate, methyl methacrylate, ethyl acrylate, isooctyl acrylate, hydroxyethyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, methacrylamide, and styrene; the polyacrylic resin is a homopolymer or copolymer polymerized from one or more of the monomers; And / or, the modified polyacrylic acid resin is copolymerized by one or more of monomers having nitrogen atom-containing functional groups, such as acrylonitrile, amine methacrylate, methacrylic acid carbamate, vinyl carbamate, acrylamide, and methacrylamide, and methacrylic acid resin monomer; And / or, the modified amino resin is one or more of methylated melamine resin, methylated hexamethylolmelamine resin, butylated melamine resin, methylated urea-formaldehyde resin and butylated urea-formaldehyde resin.

[0010] Furthermore, the weight average molecular weight of the acrylic resin is 15000-350000 g / mol; And / or, the softening temperature of the acrylic resin is 120-220°C; The weight average molecular weight of the modified polyacrylic acid resin is 15000-350000 g / mol; And / or, the softening temperature of the modified polyacrylic acid resin is 120-220°C; The weight average molecular weight of the modified polyacrylic acid resin is 20000-400000 g / mol; And / or, the softening temperature of the modified polyacrylic acid resin is 100-250°C.

[0011] Further, the first organic molecular monomer is one or more of β-carboxyethyl methacrylate, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, methacrylate monohydroxyethyl phthalate, vinyl phosphoric acid, 2-acrylamide-2-methylpropane sulfonic acid, styrene sulfonic acid, and vinyl sulfonic acid; The second organic molecular monomer is one or more of ethanolamine, diethanolamine and triethanolamine.

[0012] Furthermore, the inorganic filler is nano silicon dioxide and / or nano titanium dioxide; And / or, the solvent is one or more of toluene, butanone, ethyl acetate, n-propyl acetate, n-butyl acetate, and N,N-dimethylformamide.

[0013] In a second aspect, the present invention provides a method for preparing the high temperature resistant and solvent resistant adhesive as described in the first aspect, comprising the following steps: S1, dissolving the first organic molecule monomer and the second organic molecule monomer in a solvent and mixing them uniformly; S2, add acrylic resin, modified polyacrylic resin, and modified amino resin in sequence and mix well; S3, adding inorganic filler and stirring until fully dispersed; S4, filtering to obtain the high temperature resistant and solvent resistant adhesive.

[0014] Furthermore, in step S2, the mixing treatment is carried out at a temperature of 25 to 80°C and for a time of 2 to 5 hours.

[0015] In a third aspect, the present invention provides a PC holographic anti-counterfeiting film, comprising a release layer, an imaging layer, a dielectric layer, an adhesive layer and a PC film layer which are sequentially stacked and arranged; The adhesive layer is prepared by using the high temperature and solvent resistant adhesive as described in any one of the first aspects; The surface of the imaging layer has a holographic anti-counterfeiting pattern.

[0016] In a fourth aspect, the present invention provides a method for preparing the PC holographic anti-counterfeiting film as described in the third aspect, comprising the following steps: A release layer, an imaging layer, a dielectric layer and an adhesive layer are sequentially formed on the substrate layer to prepare a holographic transfer film; The prepared holographic transfer film and PC film layer are heat-pressed and laminated, wherein the adhesive layer of the holographic transfer film is in contact with the PC film layer, and the carrier film is peeled off to obtain the PC holographic anti-counterfeiting film.

[0017] Furthermore, the temperature of the hot pressing composite is 130-220° C., the pressure is 1-10 MPa, and the time is 10-300 s.

[0018] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: The present invention provides a high temperature resistant and solvent resistant adhesive, a PC anti-counterfeiting film and a preparation method thereof, wherein the high temperature resistant and solvent resistant adhesive comprises the following preparation raw materials in parts by weight: 40 to 80 parts of acrylic resin, 20 to 60 parts of modified polyacrylic resin, 20 to 60 parts of modified amino resin, 10 to 20 parts of a first organic molecular monomer, 10 to 20 parts of a second organic molecular monomer, 3 to 5 parts of an inorganic filler and 60 to 160 parts of a solvent.

[0019] Compared with the existing method, this scheme has the following advantages: in the present invention, acrylic resin, modified polyacrylic resin, and modified amino resin are sequentially added to a solvent in which a self-polymerizable monomer and an alcoholamine organic molecular monomer are dissolved, and the high-temperature and solvent-resistant adhesive prepared after blending and filtering can not turn yellow under high temperature, and after long-term immersion in chemical solvents, it maintains excellent adhesion to the PC substrate. At the same time, the adhesive also has good adhesion to the medium, and has good weather resistance and aging resistance. It can be applied not only to the field of financial cards, but also to various cards and certificates with PC as the substrate. In addition, the adhesive preparation method provided by the present invention is simple and low in cost, which can save time cost, better meet large-scale industrial production, and has good economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the preparation process of a high temperature resistant and solvent resistant adhesive provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Unless otherwise specified, the equipment used in the following examples are all conventional equipment in the art; the reagents used are all commercially available products or prepared by conventional methods in the art unless otherwise specified. Anything not described in detail in the following examples can be achieved by conventional experimental means in the art.

[0023] In the terms used in this embodiment, "and / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B); "Homopolymer" means a polymer composed of one monomer linked by covalent bonds; "Copolymer" means a polymer formed by the polymerization of two or more monomers, where these different monomer molecules are linked together by covalent bonds; The "medium layer" refers to a brightening layer formed by electroplating zinc sulfide on the imaging layer of the PC holographic anti-counterfeiting film. This type of medium brightening layer has high gloss.

[0024] The embodiments of the present invention provide a new holographic anti-counterfeiting film, a preparation method and application thereof.

[0025] The following is combined with Figure 1 The embodiments of the present invention are further described in detail with examples. The following examples are used to illustrate the present invention but cannot be used to limit the scope of the present invention.

[0026] The invention provides a high temperature resistant and solvent resistant adhesive, comprising the following raw materials in parts by weight: 40-80 parts of acrylic resin, 20-60 parts of modified polyacrylic resin, 20-60 parts of modified amino resin, 10-20 parts of first organic molecular monomer, 10-20 parts of second organic molecular monomer, 3-5 parts of inorganic filler and 60-160 parts of solvent.

[0027] In an optional embodiment, the monomers of the adhesive acrylic resin include methyl acrylate, butyl acrylate, methyl methacrylate, ethyl acrylate, isooctyl acrylate, hydroxyethyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, methacrylamide, and styrene; the polyacrylic resin is a homopolymer or copolymer polymerized from one or more of the monomers; And / or, the adhesive modified polyacrylic resin is copolymerized by one or more of monomers having nitrogen atom-containing functional groups, such as acrylonitrile, amine methacrylate, methacrylic carbamate, vinyl carbamate, acrylamide, and methacrylamide, and methacrylic resin monomer; And / or, the adhesive-modified amino resin is one or more of methylated melamine resin, methylated hexamethylolmelamine resin, butylated melamine resin, methylated urea-formaldehyde resin and butylated urea-formaldehyde resin.

[0028] In an optional embodiment, the weight average molecular weight of the adhesive acrylic resin is 15000-350000 g / mol; and / or, the softening temperature of the adhesive acrylic resin is 120-220°C; The weight average molecular weight of the adhesive modified polyacrylic acid resin is 15000~350000 g / mol; and / or, the softening temperature of the adhesive-modified polyacrylic acid resin is 120-220° C.; The weight average molecular weight of the adhesive modified polyacrylic acid resin is 20000~400000 g / mol; And / or, the softening temperature of the adhesive-modified polyacrylic acid resin is 100-250°C.

[0029] In an optional embodiment, the first organic molecular monomer of the adhesive is one or more of β-carboxyethyl methacrylate, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, methacrylate monohydroxyethyl phthalate, vinyl phosphoric acid, 2-acrylamide-2-methylpropane sulfonic acid, styrene sulfonic acid, and vinyl sulfonic acid; The second organic molecular monomer of the adhesive is one or more of ethanolamine, diethanolamine and triethanolamine.

[0030] In an optional embodiment, the binder inorganic filler is nano silicon dioxide and / or nano titanium dioxide; And / or, the adhesive solvent is one or more of toluene, butanone, ethyl acetate, n-propyl acetate, n-butyl acetate, and N,N-dimethylformamide.

[0031] In order to better explain the fully high temperature resistant and solvent resistant adhesive provided by the embodiment of the present invention, Figure 1 As shown, the present invention also provides a method for preparing the high temperature resistant and solvent resistant adhesive, comprising the following steps: S1, dissolving the first organic molecule monomer and the second organic molecule monomer in a solvent and mixing them uniformly; S2, add acrylic resin, modified polyacrylic resin, and modified amino resin in sequence and mix well; S3, adding inorganic filler and stirring until fully dispersed; S4, filtering to obtain the adhesive which is resistant to high temperature and solvent.

[0032] Wherein, in step S2, the temperature of the mixing treatment is 25-80°C and the time is 2-5 hours.

[0033] Furthermore, the present invention also provides a PC holographic anti-counterfeiting film, comprising a release layer, an imaging layer, a medium layer, an adhesive layer and a PC film layer which are sequentially stacked and arranged.

[0034] The adhesive bonding layer is prepared by using a high temperature and solvent resistant adhesive as claimed in any one of claims 1 to 5.

[0035] The surface of the adhesive imaging layer has a holographic anti-counterfeiting pattern.

[0036] The method for preparing the above-mentioned PC holographic anti-counterfeiting film comprises the following steps: A release layer, an imaging layer, a medium layer and an adhesive layer are sequentially formed on the substrate layer to prepare a holographic transfer film. The adhesive layer is prepared by using the above-mentioned adhesive.

[0037] Specifically, as an implementation method, the specific preparation process of the holographic transfer film is as follows: a. Applying a release layer coating on the upper surface of the substrate layer and curing it to form a release layer; b. coating an imaging layer coating on the upper surface of the release layer, and hot-pressing a holographic anti-counterfeiting pattern on the upper surface to obtain an imaging layer coating; c. evaporating a medium on the upper surface of the hot-pressed imaging layer coating to form a medium layer; d. Then, cure in a drying room at 50-100°C for 24-72 hours; e. After aging, an adhesive layer coating is applied on the upper surface of the dielectric layer to obtain a holographic transfer film.

[0038] The prepared adhesive holographic transfer film and the PC film layer are hot-pressed and laminated. The temperature of the adhesive hot-pressing and laminating is 130-220°C, the pressure is 1-10 MPa, and the time is 10-300 s. The adhesive layer of the adhesive holographic transfer film is in contact with the PC film layer, and the carrier film is peeled off to obtain the PC holographic anti-counterfeiting film.

[0039] Preferably, the adhesive carrier film is made of polyethylene terephthalate (PET) and has a thickness of 10-50 μm.

[0040] Preferably, the adhesive release layer material is a wax-containing coating with a thickness of 0.2 to 0.5 μm and a surface tension of 42 to 52 dyn / cm.

[0041] Preferably, the adhesive imaging layer material is a two-component coating of isocyanate and polyol, the thickness of which is 1 to 5 μm, and the softening temperature of the adhesive imaging layer is 190 to 230°C.

[0042] Preferably, the adhesive medium layer is made of zinc sulfide and has a thickness of 200 to 500Å.

[0043] Preferably, the thickness of the adhesive bonding layer is 1-5 μm.

[0044] Preferably, the material of the adhesive substrate layer is polycarbonate (PC), the thickness of which is 50-100 μm and the surface roughness of which is Ra0.1-6.

[0045] The following is further introduced in conjunction with specific embodiments: Example 1 This embodiment provides a high temperature resistant and solvent resistant adhesive and a preparation method thereof, and a specific preparation process of the corresponding PC holographic anti-counterfeiting film is as follows: The preparation process of high temperature resistant and solvent resistant adhesive is: Step S1, placing 15 parts of the first organic molecule monomer and 15 parts of the second organic molecule monomer in a stirring device, then adding 100 parts of a solvent, and stirring at 25° C. for 30 min; Step S2, add 50 parts of acrylic resin, 25 parts of modified polyacrylic resin, and 25 parts of modified amino resin in sequence, and stir at 80°C for 2h; Step S3, then add 4 parts of inorganic filler and stir until it is completely dispersed; and obtain a high temperature resistant and solvent resistant adhesive after filtering.

[0046] Among them, the monomers of acrylic resin include methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate or butyl acrylate, and the adhesive polyacrylic resin is a homopolymer or copolymer polymerized from one or more of the above monomers, with a molecular weight of 15,000 to 30,000.

[0047] The modified polyacrylic acid resin is copolymerized from monomers acrylonitrile having nitrogen-containing functional groups, amine methacrylate, and methacrylic acid resin monomers.

[0048] The modified amino resin is methyl etherified melamine resin.

[0049] The inorganic filler is nano silicon dioxide.

[0050] The solvent selected was n-propyl acetate.

[0051] The first organic molecular monomer is 2-acrylamide-2-methylpropane sulfonic acid; and the second organic molecular monomer is ethanolamine.

[0052] The present application also provides a method for preparing a PC holographic anti-counterfeiting film, comprising the following steps: Step 1: Form a release layer, an imaging layer with a holographic anti-counterfeiting pattern on the surface, a medium layer and an adhesive layer on the carrier layer in sequence to prepare a holographic transfer film. The adhesive layer is prepared by using the adhesive prepared above.

[0053] The specific preparation process of holographic transfer film is as follows: a. Apply a release layer coating on the upper surface of the carrier layer and solidify it to form a release layer; b. coating an imaging layer coating on the upper surface of the release layer, and hot-pressing a holographic anti-counterfeiting pattern on the upper surface to obtain an imaging layer coating; c. evaporating a medium on the upper surface of the hot-pressed imaging layer coating to form a medium layer; d. Then, cure in a drying room at 100°C for 24 hours; e. After aging, an adhesive layer coating is applied on the upper surface of the dielectric layer to obtain a holographic transfer film.

[0054] Step 2: hot-press the prepared holographic transfer film and the substrate layer, wherein the adhesive layer of the holographic transfer film contacts the substrate, and the adhesive layer is activated under the action of temperature and pressure to be firmly bonded to the substrate layer, and the carrier film layer is peeled off to obtain a multi-layer PC anti-counterfeiting film.

[0055] The adhesive carrier layer is a PET film with a thickness of 19 μm. The adhesive release layer is formed by coating a wax-containing coating with a coater, and has a thickness of 0.2 μm and a surface tension of 42 dyn / cm. The adhesive imaging layer is formed by coating a two-component coating of isocyanate and polyol through a coating machine, and the surface adjacent to the medium layer has a holographic anti-counterfeiting pattern. The coating corresponding to the imaging layer includes isocyanate, propylene polyol, and 2,4,5-triamino-6-hydroxypyrimidine sulfate. The mass ratio of isocyanate, propylene polyol, and 2,4,5-triamino-6-hydroxypyrimidine sulfate is 30:65:5. The thickness of the adhesive imaging layer is 2μm, and the softening temperature of the adhesive imaging layer is 220°C. The adhesive dielectric layer is formed by evaporation through an electroplating process. The material of the dielectric layer is zinc sulfide and its thickness is 380Å. The adhesive bonding layer was formed by coating with a coater and had a thickness of 2 μm. The material of the adhesive substrate layer is polycarbonate, with a thickness of 50 μm and a surface roughness of Ra2.

[0056] The adhesive hot pressing bonding temperature was 130 °C, the pressure was 2 MPa, and the time was 30 s.

[0057] Example 2 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the modified amino resin in Embodiment 1 is a methylated melamine resin, while the modified amino resin in this embodiment is a melamine resin, and the remaining components and steps are the same.

[0058] The specific steps are as follows: 15 parts of the first organic molecule monomer and 15 parts of the second organic molecule monomer are placed in a stirring device, and then 100 parts of a solvent are added, and stirred at 25°C for 30 minutes; 50 parts of an acrylic resin, 25 parts of a modified polyacrylic resin, and 25 parts of a melamine resin are added in sequence, and stirred at 80°C for 2 hours; then 4 parts of an inorganic filler are added, and stirred until fully dispersed; and a high temperature and solvent resistant adhesive is obtained after filtering.

[0059] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0060] Example 3 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the modified amino resin in Embodiment 1 is a methylated melamine resin, while the modified amino resin in this embodiment is a urea-formaldehyde resin, and the remaining components and steps are the same.

[0061] 15 parts of the first organic molecule monomer and 15 parts of the second organic molecule monomer are placed in a stirring device, and then 100 parts of the solvent are added, and stirred at 25°C for 30 minutes; 50 parts of acrylic resin, 25 parts of modified polyacrylic resin, and 25 parts of urea-formaldehyde resin are added in sequence, and stirred at 80°C for 2 hours; then 4 parts of inorganic filler are added, and stirred until fully dispersed; after filtering, a high temperature and solvent-resistant adhesive is obtained.

[0062] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0063] Example 4 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the modified polyacrylic acid resin in Embodiment 1 is copolymerized from monomers acrylonitrile having nitrogen atom functional groups, amine methyl acrylate, and methacrylic acid resin monomers; the present embodiment is an acrylic resin polymerized from vinyl acetate and methacrylic acid, and the remaining components and steps are the same.

[0064] 15 parts of the first organic molecular monomer and 15 parts of the second organic molecular monomer are placed in a stirring device, and then 100 parts of the solvent are added, and stirred at 25°C for 30 minutes; 50 parts of acrylic resin, 25 parts of acrylic resin polymerized by vinyl acetate and methacrylic acid, and 25 parts of modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then 3 parts of inorganic filler are added, and stirred until fully dispersed; after filtering, a high temperature and solvent resistant adhesive is obtained.

[0065] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0066] Example 5 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the modified polyacrylic resin in Embodiment 1 is copolymerized from monomers acrylonitrile, amino methacrylate, and methacrylic resin monomers having nitrogen atom functional groups; the present embodiment uses acrylic resin and modified amino resin polymerized from glycidyl methacrylate and methacrylic acid, and the remaining components and steps are the same.

[0067] 15 parts of the first organic molecule monomer and 15 parts of the second organic molecule monomer are placed in a stirring device, and then 100 parts of a solvent are added, and stirred at 25°C for 30 minutes; 50 parts of an acrylic resin, an acrylic resin polymerized from glycidyl methacrylate and methacrylic acid, and 25 parts of a modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then 3 parts of an inorganic filler are added, and stirred until fully dispersed; and a high temperature and solvent resistant adhesive is obtained after filtration.

[0068] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0069] Example 6 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the first organic molecular monomer in Embodiment 1 is 2-acrylamide-2-methylpropane sulfonic acid; the first organic molecular monomer in this embodiment is maleic anhydride monomer, and the remaining components and steps are the same.

[0070] 15 parts of maleic anhydride monomer and 15 parts of the second organic molecule monomer are placed in a stirring device, and then 100 parts of a solvent are added, and stirred at 25°C for 30 minutes; 50 parts of acrylic resin, 25 parts of modified polyacrylic resin, and 25 parts of modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then 4 parts of an inorganic filler are added, and stirred until fully dispersed; after filtering, a high temperature and solvent resistant adhesive is obtained.

[0071] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0072] Example 7 This embodiment provides an adhesive and a preparation method thereof. The difference from Embodiment 1 is that the first organic molecular monomer in Embodiment 1 is dimethyl itaconate monomer; in this embodiment, it is maleic anhydride monomer, and the remaining components and steps are the same.

[0073] 15 parts of dimethyl itaconate monomer and 15 parts of the second organic molecule monomer are placed in a stirring device, and then 100 parts of a solvent are added, and stirred at 25°C for 30 minutes; 50 parts of acrylic resin, 25 parts of modified polyacrylic resin, and 25 parts of modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then an inorganic filler is added and stirred until it is completely dispersed; and a high temperature and solvent resistant adhesive is obtained after filtering.

[0074] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0075] Example 8 This embodiment provides an adhesive and a preparation method thereof, which is different from Embodiment 1 in that the raw materials of the high temperature and solvent resistant adhesive are the same as those in Embodiment 1, but the component proportions of the raw materials are different. The remaining components and steps are the same.

[0076] 20 parts of the first organic molecule monomer and 20 parts of the second organic molecule monomer are placed in a stirring device, and then 160 parts of a solvent are added, and stirred at 25°C for 30 minutes; 80 parts of an acrylic resin, 60 parts of a modified polyacrylic resin, and 60 parts of a modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then 5 parts of an inorganic filler are added, and stirred until fully dispersed; and a high temperature and solvent resistant adhesive is obtained after filtration.

[0077] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0078] Example 9 This embodiment provides an adhesive and a preparation method thereof, which is different from Embodiment 1 in that the raw materials of the high temperature and solvent resistant adhesive are the same as those in Embodiment 1, but the component proportions of the raw materials are different. The remaining components and steps are the same.

[0079] 10 parts of the first organic molecule monomer and 10 parts of the second organic molecule monomer are placed in a stirring device, and then 60 parts of a solvent are added, and stirred at 25°C for 30 min; 40 parts of an acrylic resin, 40 parts of a modified polyacrylic resin, and 40 parts of a modified amino resin are added in sequence, and stirred at 80°C for 2 hours; then 3 parts of an inorganic filler are added, and stirred until fully dispersed; and a high temperature and solvent resistant adhesive is obtained after filtering.

[0080] A corresponding PC holographic anti-counterfeiting film and a preparation method thereof are also provided, which are the same as those in Example 1 and will not be described in detail here.

[0081] Comparative Example 1 This comparative example provides a high temperature solvent resistant adhesive and a preparation method thereof, which is basically the same as Example 1, except that the weight of the acrylic resin is increased from 50 parts to 75 parts, and no modified amino resin is added.

[0082] The rest of the steps are the same as those in Example 1.

[0083] Comparative Example 2 This comparative example provides a high temperature solvent resistant adhesive and a preparation method thereof, which is basically the same as Example 1, except that the weight of the acrylic resin is increased from 50 parts to 75 parts, and no modified polyacrylic acid resin is added.

[0084] The rest of the steps are the same as those in Example 1.

[0085] Comparative Example 3 This comparative example provides a high temperature solvent resistant adhesive and a preparation method thereof, which is basically the same as Example 1, except that the weight of the solvent is increased from 100 parts to 130 parts, and the first organic molecular monomer and the second organic molecular monomer are not added.

[0086] The rest of the steps are the same as those in Example 1.

[0087] The properties of the adhesives prepared in Examples 1 to 9 and Comparative Examples 1 to 3 were tested: 1. Adhesion test: Conduct experimental test in accordance with GB / T 9286-1998 (100-grid method).

[0088] 2. High temperature yellowing test: Put the PC holographic anti-counterfeiting film into a laminator at 200 ℃ for lamination, the lamination time is 30 minutes, the lamination pressure is 2MPa, observe whether yellowing occurs, and test the yellowing value. Among them, ∆E<3 is a high temperature yellowing sample with good performance; 3%<∆E≤10% is an acceptable high temperature yellowing sample; 10%<∆E≤20% is an unqualified high temperature yellowing sample; ∆E>200% is a poor high temperature yellowing sample.

[0089] 3. Solvent resistance test: prepare a PC holographic anti-counterfeiting film with a size of 40*25mm, and prepare the following test solvents with a content of 5% - Solvent No. 1: 5% ethyl acetate; Solvent No. 2: 5% benzene; Solvent No. 3: 5% trichloroethylene; Solvent No. 4: 5% hydrochloric acid; Solvent No. 5: 5% sodium hydroxide; Solvent No. 6: 5% sodium sulfide, and soak the PC holographic anti-counterfeiting film in 20mL of the corresponding detection reagent solution at 25℃ for 2 hours, take it out, wash it with clean water, cover it with a piece of filter paper, sandwich it between two glass plates, put a 1kg weight on it, and let it stand for a while. When the specimen and test paper are dry, check the filter paper, test the peeling area, and calculate the average peeling area of ​​each group of test samples. Among them, the average peeling area ≤5% is a solvent-resistant sample with good performance; 5% < average peeling area ≤15% is an acceptable solvent-resistant sample; and the average peeling area >15% is an unqualified solvent-resistant sample.

[0090] The results of the above performance tests are statistically shown in Tables 1, 2 and 3.

[0091] Table 1 Adhesion performance test results of embodiments and comparative examples

[0092] Table 2 Test results of high temperature yellowing resistance of examples and comparative examples

[0093] Table 3 Solvent resistance test results of examples and comparative examples

[0094] It can be seen from the test results in Table 1 that, compared with the adhesive provided in the comparative example, the adhesive provided in the embodiment of the present invention has good adhesion and meets the test standard. Among them, when the modified polyacrylic acid resin is a nitrogen-modified polyacrylate resin (Example 1), the adhesive layer has excellent adhesion to the PC substrate and the zinc sulfide dielectric layer respectively, and when the modified polyacrylic acid resin is an acrylic resin polymerized by vinyl acetate and methacrylic acid (Example 4) or an acrylic resin polymerized by glycidyl methacrylate and methacrylic acid (Example 5), the adhesion of the adhesive layer to the PC substrate or the zinc sulfide dielectric layer will decrease, but both are better than the comparative example 2 without the modified polyacrylic acid resin.

[0095] It can be seen from the test results in Table 2 that, compared with the adhesive provided in the comparative example, the adhesive provided in the embodiments of the present invention has good high temperature yellowing resistance. Among them, when the main resin contains methyl etherified melamine resin (Example 1) and the monomer contains a self-polymerizable monomer, the adhesive layer has excellent high temperature yellowing resistance, and when the adhesive does not contain or the modified amino resin is selected from melamine resin (Example 2) or urea-formaldehyde resin (Example 3), the high temperature yellowing resistance of the adhesive layer is not as good as the adhesive layer provided in Example 1, but is worse than the comparative example 1 without modified amino resin.

[0096] In addition, when the adhesive contains maleic anhydride (Example 6) with a lower reaction activity monomer or dimethyl itaconate (Example 7) with a strong inhibitory effect monomer, the high temperature yellowing resistance of the adhesive layer will be worse than that of the adhesive provided in Example 1 where the first monomer is 2-acrylamide-2-methylpropane sulfonic acid; but the performance is better than that of Comparative Example 1 which does not contain the first organic molecule monomer and the second organic molecule monomer.

[0097] It can be seen from the test results in Table 3 that when the adhesive contains modified polyurethane methyl ether melamine resin, the solvent resistance of the adhesive is improved, and when the first organic molecular monomer in the adhesive is a self-polymerization type monomer 2-acrylamide-2-methylpropane sulfonic acid (Example 1), the solvent resistance of the adhesive layer reaches the best.

[0098] In summary, in the present invention, acrylic resin, modified polyacrylic resin, and modified amino resin are sequentially added into a solvent in which self-polymerizable monomers and alcoholamine organic molecular monomers are dissolved, and the high-temperature and solvent-resistant adhesive prepared after blending and filtering can avoid yellowing under high temperature, and can maintain excellent adhesion to the PC substrate after long-term immersion in chemical solvents. At the same time, the adhesive also has good adhesion to the medium, and has good weather resistance and aging resistance. It is not only suitable for the field of financial cards, but also suitable for various cards and certificates with PC as the substrate.

[0099] In addition, the preparation method of the adhesive provided by the present invention is simple and low-cost, which can save time costs, better meet large-scale industrial production, and has good economic value.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high temperature and solvent resistant adhesive, characterized in that: The preparation method comprises the following raw materials in parts by weight: 40-80 parts of acrylic resin, 20-60 parts of modified polyacrylic resin, 20-60 parts of modified amino resin, 10-20 parts of first organic molecular monomer, 10-20 parts of second organic molecular monomer, 3-5 parts of inorganic filler and 60-160 parts of solvent.

2. The high temperature and solvent resistant adhesive according to claim 1, characterized in that: The monomers of the acrylic resin include methyl acrylate, butyl acrylate, methyl methacrylate, ethyl acrylate, isooctyl acrylate, hydroxyethyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, methacrylamide, and styrene; the polyacrylic resin is a homopolymer or copolymer polymerized from one or more of the monomers; And / or, the modified polyacrylic acid resin is copolymerized by one or more of monomers having nitrogen atom-containing functional groups, such as acrylonitrile, amine methacrylate, methacrylic acid carbamate, vinyl carbamate, acrylamide, and methacrylamide, and methacrylic acid resin monomer; And / or, the modified amino resin is one or more of methylated melamine resin, methylated hexamethylolmelamine resin, butylated melamine resin, methylated urea-formaldehyde resin and butylated urea-formaldehyde resin.

3. The high temperature and solvent resistant adhesive according to claim 1, characterized in that: The weight average molecular weight of the acrylic resin is 15000-350000 g / mol; And / or, the softening temperature of the acrylic resin is 120-220°C; The weight average molecular weight of the modified polyacrylic acid resin is 15000-350000 g / mol; And / or, the softening temperature of the modified polyacrylic acid resin is 120-220°C; The weight average molecular weight of the modified polyacrylic acid resin is 20000-400000 g / mol; And / or, the softening temperature of the modified polyacrylic acid resin is 100-250°C.

4. The high temperature and solvent resistant adhesive according to claim 1, characterized in that: The first organic molecule monomer is one or more of β-carboxyethyl methacrylate, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, monohydroxyethyl methacrylate phthalate, vinyl phosphoric acid, 2-acrylamide-2-methylpropane sulfonic acid, styrene sulfonic acid, and vinyl sulfonic acid; The second organic molecular monomer is one or more of ethanolamine, diethanolamine and triethanolamine.

5. The high temperature and solvent resistant adhesive according to claim 1, characterized in that: The inorganic filler is nano silicon dioxide and / or nano titanium dioxide; And / or, the solvent is one or more of toluene, butanone, ethyl acetate, n-propyl acetate, n-butyl acetate, and N,N-dimethylformamide.

6. A method for preparing a high temperature resistant and solvent resistant adhesive according to any one of claims 1 to 5, characterized in that: The steps include: S1, dissolving the first organic molecule monomer and the second organic molecule monomer in a solvent and mixing them uniformly; S2, add acrylic resin, modified polyacrylic resin, and modified amino resin in sequence and mix well; S3, adding inorganic filler and stirring until fully dispersed; S4, filtering to obtain the high temperature resistant and solvent resistant adhesive.

7. The method for preparing a high temperature resistant and solvent resistant adhesive according to claim 6, characterized in that: In step S2, the mixing treatment is performed at a temperature of 25 to 80°C for a time of 2 to 5 hours.

8. A PC holographic anti-counterfeiting film, characterized in that: It includes a release layer, an imaging layer, a medium layer, an adhesive layer and a PC film layer which are stacked in sequence; The adhesive layer is prepared by using the high temperature and solvent resistant adhesive as described in any one of claims 1 to 5; The surface of the imaging layer has a holographic anti-counterfeiting pattern.

9. A method for preparing a PC holographic anti-counterfeiting film as claimed in claim 8, characterized in that: The steps include: A release layer, an imaging layer, a dielectric layer and an adhesive layer are sequentially formed on the substrate layer to prepare a holographic transfer film; The prepared holographic transfer film and PC film layer are heat-pressed and laminated, the adhesive layer of the holographic transfer film is in contact with the PC film layer, and the carrier film is peeled off to obtain the PC holographic anti-counterfeiting film.

10. The method for preparing the PC holographic anti-counterfeiting film according to claim 9, characterized in that: The temperature of the hot pressing composite is 130-220° C., the pressure is 1-10 MPa, and the time is 10-300 s.

Images