Thermal transfer printing protective carbon tape with high weather resistance and self-cleaning performance

Abstract

The present application relates to a kind of thermal transfer printing protective carbon tape with high weather resistance and self-cleaning performance, the substrate of the carbon tape is provided with protective layer;The protective layer is coated by protective layer coating, and the crosslinked resin in the protective layer coating includes the crosslinking of thermosetting fluorocarbon resin, thermosetting acrylic resin and ultraviolet absorber under the action of crosslinking agent.The front layer of the carbon tape of the present application is printed on the printing material, since the ultraviolet absorber is bonded on the resin by crosslinking reaction, the ultraviolet absorber is avoided to migrate to the surface and cause failure, and the transfer layer is simultaneously endowed with sufficient friction resistance and light resistance, and simultaneously has good self-cleaning performance, the time of printing material is used outdoors and the dirt resistance is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heat transfer printing consumables, and particularly relates to a heat transfer printing protective carbon tape with high weather resistance and self-cleaning performance. BACKGROUND

[0002] Currently, heat transfer printing or inkjet is a relatively reliable and economical method for coloring a reflective film. However, the road traffic reflective film prepared by using such a method needs to be used outdoors for many years, and therefore has high requirements for weather resistance. To this end, a common method is to add a transparent protective film outside the ink, and the protective film needs to have the functions of preventing external damage and pollution, and preventing ultraviolet light from accelerating the aging of the ink to affect the chroma and reflective performance of the traffic reflective film.

[0003] An ultraviolet absorber can effectively prevent or delay the destruction of the molecular structure of a material and the reduction of performance, and prolong the service life of the material. Currently, a common method for improving the aging resistance of a material is to add a small-molecule ultraviolet absorber to the material to avoid degradation of the high-molecular material by ultraviolet light. However, the small-molecule ultraviolet absorber directly added to the material is prone to migration and exudation in the storage and use process due to the influence of the external environment, thereby reducing the ultraviolet absorption performance of the material. SUMMARY

[0004] The technical problem to be solved by the present application is to prevent the ultraviolet absorber in the material from migrating to the surface and causing failure. The present application bonds the ultraviolet absorber to the resin through a cross-linking reaction, thereby avoiding the migration of the ultraviolet absorber to the surface and causing failure.

[0005] The technical solution of the present application for solving the above technical problem is as follows: a heat transfer printing protective carbon tape with high weather resistance and self-cleaning performance, wherein a protective layer is arranged on the base of the carbon tape.

[0006] The protective layer is coated by a protective layer coating, and the protective layer coating comprises a cross-linked resin formed by cross-linking of a thermosetting fluorocarbon resin, a thermosetting acrylic resin and an ultraviolet absorber under the action of a cross-linking agent.

[0007] Principle of the present application:

[0008] The fluorocarbon resin takes the firm C-F bond as a skeleton, and compared with other resins, it has better heat resistance, chemical resistance, cold resistance, low-temperature flexibility, weather resistance and electrical properties, and has non-stickiness and non-wettingness due to its good crystallinity. The present application takes the thermosetting fluorocarbon resin as the main resin, and adds the thermosetting acrylic resin, so that the protective layer can be directly attached to the transferred body by heat transfer printing. The C-F bond in the fluorocarbon resin has high bond energy (460 kJ / mol) and high stability, and the spiral arrangement of fluorine atoms plays a good "shielding protection" role on the carbon main chain, which can effectively prevent the exposure of carbon atoms and carbon chains, so that the fluorinated acrylic ester has excellent weather resistance, corrosion resistance and chemical medium resistance. In the film forming process, the fluorine alkyl group with extremely low surface energy will migrate to the surface first, so that the coating film surface has excellent hydrophobic, oleophobic, anti-staining and other properties. After the acrylic modification, the adhesion of the fluorocarbon resin to the printing material is improved, and the crosslinking degree and the solvent resistance of the resin are further improved.

[0009] The present application introduces the ultraviolet absorber into the crosslinked resin formed by the thermosetting fluorocarbon resin and the thermosetting acrylic resin in a chemical bonding manner, obtains a high molecular ultraviolet absorber, and makes it not easy to migrate and seep out in the storage and use process due to the influence of the external environment, thereby reducing the ultraviolet absorption performance of the material, so that the resin has excellent aging resistance.

[0010] The beneficial effects of the present application are that the front layer (one side containing the protective layer) of the carbon tape is printed on the printing material, and since the ultraviolet absorber is bonded to the resin through crosslinking reaction, the ultraviolet absorber is prevented from migrating to the surface to cause failure. At the same time, the low surface energy of the fluorocarbon resin gives the transferred layer sufficient abrasion resistance and light resistance, and also has good self-cleaning performance, which improves the outdoor use time and dirt resistance of the printing material.

[0011] It should be noted that the ultraviolet absorber of the present application is a non-reactive ultraviolet absorber such as salicylate, benzophenone, benzotriazole, triazine, substituted acrylonitrile, nickel chelate, hindered amine, etc. after introducing addition polymerizable double bonds such as vinyl, acryl, methacryl, or alcoholic hydroxyl, amino, carboxyl, epoxy, isocyanate groups.

[0012] On the basis of the above technical solution, the present application can also be improved as follows.

[0013] Further, the thermosetting fluorocarbon resin is FEVE fluorocarbon resin; and / or

[0014] The thermosetting acrylic resin is a hydroxyl acrylic resin; and / or

[0015] The ultraviolet absorber is an ultraviolet absorber containing alcoholic hydroxyl groups.

[0016] The beneficial effect of the further scheme is that the hydroxyl-containing thermosetting resin does not produce by-products through the reaction of the polyisocyanate curing agent, and the cross-linking reaction is easier to control.

[0017] Further, the fluorine content in the thermosetting fluorocarbon resin is 10-45%, the molecular weight of the thermosetting fluorocarbon resin is 1000-20000, and the hydroxyl value is 10-100 mgKOH / g; and / or

[0018] The molecular weight of the thermosetting acrylic resin is 1000-30000, and the hydroxyl value is 10-100 mgKOH / g.

[0019] The beneficial effect of the further scheme is that the fluorine content in the thermosetting fluorocarbon resin is too low, which reduces the weather resistance and self-cleaning performance, and the fluorine content is too high, which reduces the adhesion of the resin. The resin with the above-mentioned molecular weight can facilitate the control of the molecular weight during the cross-linking reaction and the ratio of the resins during the cross-linking reaction.

[0020] Further, the preparation method of the cross-linked resin comprises: reacting the thermosetting fluorocarbon resin and the thermosetting acrylic resin through the cross-linking agent at 50-90°C to form a prepolymer, and then adding an ultraviolet absorber and reacting at 50-90°C to obtain a cross-linked resin.

[0021] The beneficial effect of the further scheme is that several resins with different characteristics are polymerized together through the cross-linking agent, and the cross-linked resin obtained can have the advantages of the above-mentioned resins, while increasing the molecular weight of the resin and improving the resistance and stability of the resin.

[0022] Further, the mass ratio of the thermosetting fluorocarbon resin, the thermosetting acrylic resin, and the ultraviolet absorber is (50-80):(10-40):(10-30); and / or

[0023] The cross-linking agent is a polyisocyanate cross-linking agent containing at least three isocyanate groups on a single cross-linking agent molecule, and the molar ratio of the isocyanate groups of the polyisocyanate cross-linking agent to the total hydroxyl value of the thermosetting fluorocarbon resin, the thermosetting acrylic resin, and the ultraviolet absorber is (0.9-2):1.

[0024] The beneficial effect of the above further scheme is that by controlling the mass ratio of the thermosetting fluorocarbon resin, the thermosetting acrylic resin and the ultraviolet absorber, the cross-linked resin has a suitable fluorine content, which is beneficial to ensure the self-cleaning performance and wear resistance, too low will reduce its effect, too high may cause poor compatibility with the adhesive layer or the printing layer, resulting in poor adhesion. The suitable content of the acrylic resin is beneficial to ensure the compatibility with the adhesive layer or the printing layer. And the suitable content of the ultraviolet absorber is beneficial to the light resistance of the cross-linked resin, and the light resistance is relatively reduced, and the higher one cannot fully play a role in the resin, causing waste. The polyisocyanate cross-linking agent can promote the mutual cross-linking between the thermosetting acrylic resin, the thermosetting fluorocarbon resin and the ultraviolet absorber.

[0025] It should be noted that the polyisocyanate cross-linking agent in the present application can be an oligomer formed by isophorone diisocyanate, toluene diisocyanate and diphenyl methane diisocyanate and the like.

[0026] Further, the protective layer coating further comprises a thermoplastic resin, a free radical trapping agent; and / or

[0027] The thermoplastic resin is at least one of an acrylic resin, a chloroethylene-vinyl acetate resin, a chloroethylene-vinyl isobutyl ether resin, a polyurethane resin, and an ethylene-vinyl acetate resin; and / or

[0028] The free radical trapping agent is a hindered amine free radical trapping agent, the molecular weight of the free radical trapping agent is greater than 3000, and the content of the free radical trapping agent in the protective layer coating is 1wt%-20wt%.

[0029] The beneficial effect of the above further scheme is that the thermoplastic resin can improve the adhesion between the protective layer and the adhesive layer. The free radical trapping agent can further strengthen the ultraviolet resistance of the protective layer. The free radical trapping agent with a molecular weight greater than 3000 has better stability and can prolong its action time.

[0030] It should be noted that the thermoplastic resin in the present application can be one or more of an acrylic resin, a chloroethylene-vinyl acetate, a chloroethylene-vinyl isobutyl ether, a polyurethane, and an ethylene-vinyl acetate.

[0031] Further, the carbon tape further comprises an adhesive layer, a release layer and a back coating layer, the adhesive layer, the protective layer, the release layer, the substrate and the back coating layer are sequentially attached from top to bottom;

[0032] The substrate is any one of polypropylene, polyethylene terephthalate, polyethylene terephthalate, polyethylene, polyvinyl alcohol and polymethyl methacrylate;

[0033] The base material is any one of polypropylene, polyethylene terephthalate, polyethylene terephthalate, polyethylene, polyvinyl alcohol and polymethyl methacrylate;

[0034] The release layer is coated by a release liquid, the release liquid comprising a bonding resin and wax powder;

[0035] The adhesive layer is coated by an adhesive liquid, the adhesive liquid comprising a thermoplastic acrylic resin.

[0036] The beneficial effects of the above further solutions are that the release layer can ensure that the protective layer and the base material can better separate during heat transfer printing, and the release layer can also have a smooth effect on the surface of the protective layer after heat transfer printing, thereby improving the friction resistance of the protective layer. The adhesive layer can better adhere the protective layer to the transferred body, so as to adapt to various different base materials. The thermoplastic acrylic resin can make the adhesive layer have good aging resistance and good adhesion. The back coating layer can prevent the generation of stickiness or wrinkles on the back side of the base material (the side of the base material without the protective layer) caused by heating during heat transfer printing.

[0037] It should be noted that the bonding resin can be one or more of acrylic resin, chlorovinyl-vinyl acetate, chlorovinyl-vinyl isobutyl ether, polyurethane, ethylene-vinyl acetate, rosin resin, terpene resin and polyester resin. The wax powder can be one or more of Fischer-Tropsch wax, polyethylene wax (PE wax), polytetrafluoroethylene wax, polypropylene wax (PP wax), ethylene-vinyl acetate copolymer wax (EVA wax), oxidized polyethylene wax, carnauba wax and beeswax, or can be a substance obtained by chemical modification of the above-mentioned wax. The protective layer, the colored layer and the back coating layer of the present application can add leveling agents, defoaming agents and other auxiliary agents according to requirements.

[0038] Further, the particle size D50 of the release liquid is 0.1-0.5 μm; and / or

[0039] The mass ratio of the bonding resin and the wax powder in the release liquid is 3:(7-27); and / or

[0040] The bonding resin is ethylene-vinyl acetate resin, and the wax powder is polyethylene wax powder or polytetrafluoroethylene modified polyethylene wax powder; and / or

[0041] The drop melting point of the wax powder is 90-130℃, and the medium particle size is 3-8 μm.

[0042] The beneficial effect of the further scheme is that the particle size D50 of the release liquid is kept at 0.1-0.5 μm, which can ensure the coating film surface to be fine. The ethylene-vinyl acetate resin can ensure the release layer to have certain adhesion to the substrate and the protective layer. Controlling the mass ratio of the adhesive resin and the wax powder can make the release layer have good cold-heat peeling effect and suitable adhesion to the substrate and the protective layer.

[0043] Further, the thickness of the substrate is 4-25 μm, the thickness of the adhesive layer is 0.1-1.0 μm, the thickness of the release layer is 0.1-2.0 μm, the thickness of the protective layer is 0.5-20.0 μm, and the thickness of the back coating layer is 0.2-1.0 μm.

[0044] The beneficial effect of the further scheme is that the thickness of the substrate in this range can ensure the substrate to have suitable strength, too thin strength is not enough, and belt breakage may occur in the coating or printing process, and too thick will increase the heat required for transfer printing, which is not conducive to transfer printing. Too thin adhesive layer will affect the adhesion of the protective layer on the printing layer, and too thick will increase the heat required for transfer printing. Too thin release layer will affect the peeling of the protective layer, which may lead to insufficient peeling, and too thick will increase the heat required for transfer printing and affect the light transmittance of the protective layer. Too thin protective layer will not achieve the ideal protection effect, and too thick will increase the heat required for transfer printing. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 The layer structure of the heat transfer printing protective carbon tape with high weather resistance and self-cleaning performance according to the embodiments of the present application is shown in the figure. DETAILED DESCRIPTION

[0046] The principles and features of the present application are described below, and the examples are only used to explain the present application and not to limit the scope of the present application. If the specific technology or condition is not specified in the embodiments, it is performed according to the technology or condition described in the literature in the art or according to the product manual. If the manufacturer of the reagent or instrument is not specified, it is a conventional product that can be purchased through a regular channel.

[0047] The following describes the materials and reagents used in the experiments:

[0048] Thermosetting acrylic resin (hydroxy acrylic resin): Kunshan Castor High Polymer Material Co., Ltd.

[0049] Thermosetting fluorocarbon resin (FEVE fluorocarbon resin): Shanghai Donglu Fluorine Chemical Technology Co., Ltd.

[0050] Polyisocyanate curing agent: Asahi Kasei Corporation

[0051] Reaction type ultraviolet absorber: Tianjin Li'an Long New Material Co., Ltd.

[0052] Example 1

[0053] A thermal transfer protective carbon ribbon with high weather resistance and self-cleaning performance and a preparation method thereof (as shown in Figure 1

[0054] (1) Mix 40 parts of 2-butanone, 35 parts of toluene, 10 parts of polyurethane-modified silicone resin, 10 parts of acrylic-modified silicone resin, 3 parts of zinc stearate, and 2 parts of glycerol dioleate to obtain a back coating liquid;

[0055] (2) Mix 30 parts of 2-butanone, 60 parts of toluene, 2 parts of ethylene-vinyl acetate copolymer (Mitsui Chemical 210W), and 8 parts of PE wax powder (Angel Wax Powder PEW-0200, medium particle size: 5 μm, melting point: 110°C), and then grind them in a grinder (horizontal grinder, zirconium bead particle size: 0.6 mm) to obtain a release liquid with an average particle size D50 = 0.1-0.4 μm;

[0056] (3) Mix 100 parts of a crosslinking resin solution, 3 parts of a free radical trapping agent (polybutanedioic acid (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol) ester, UV-622, Tianjin Li'Anlong New Material Co., Ltd.), and 5 parts of a thermoplastic resin (MB-2660, Mitsubishi Chemical Corporation) to obtain a protective layer coating;

[0057] (4) Mix 45 parts of 2-butanone, 45 parts of toluene, and 10 parts of a thermoplastic acrylic resin (BR-83, Mitsubishi Chemical Corporation) to obtain an adhesive liquid;

[0058] (5) Use a polyethylene terephthalate (PET) film with a thickness of 4.5 μm as a base material, apply a 60% corona discharge on one side of the base material, and coat the back coating liquid on the side of the base material with the corona discharge by gravure coating, so that the thickness of the dried back coating layer is 0.4 μm;

[0059] Coat the release liquid on the other side of the base material, so that the thickness of the dried release layer is 0.2 μm;

[0060] Further coat the protective layer coating on the release layer by gravure coating, so that the thickness of the dried protective layer is 3 μm;

[0061] Then coat the adhesive liquid on the protective layer by gravure coating, so that the thickness of the dried adhesive layer is 0.8 μm, to obtain a thermal transfer protective carbon ribbon with high weather resistance and self-cleaning performance.

[0062] ​​The cross-linking resin solution of the protective layer is prepared by the following steps: 6 parts of thermosetting acrylic resin (hydroxyl value: 55 mgKOH / g; molecular weight: 4000) and 15 parts of thermosetting fluorocarbon resin (fluorine content: 23%; hydroxyl value: 65 mgKOH / g; molecular weight: 3000) are dissolved in 50 parts of 2-butanone and 23 parts of toluene, 3 parts of polyisocyanate curing agent (-NCO content: 19 wt%) is added, and the mixture is reacted at 60°C for 30 min with stirring at 1000 r / min, then 3 parts of reactive ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyl oxypropoxy) benzophenone) is added, and the mixture is continuously reacted at 60°C for 30 min with stirring at 1000 r / min to obtain the cross-linking resin solution.

[0063] Example 2

[0064] The difference between this example and Example 1 is that the mass parts of the raw materials of the cross-linking resin solution of the protective layer are as follows: 2-butanone 50 parts, toluene 23 parts, thermosetting acrylic resin (hydroxyl value: 65 mgKOH / g; molecular weight: 4000) 6 parts, thermosetting fluorocarbon resin (fluorine content: 23%; hydroxyl value: 55 mgKOH / g; molecular weight: 3000) 15 parts, reactive ultraviolet absorber (UV-1130, Tianjin Li'An Long New Material Co., Ltd.) 3 parts, and polyisocyanate compound (-NCO content: 19 wt%) 3 parts.

[0065] Example 3

[0066] The difference between this example and Example 1 is that the mass parts of the raw materials of the cross-linking resin solution of the protective layer are as follows: 2-butanone 50 parts, toluene 23 parts, thermosetting acrylic resin (hydroxyl value: 73 mgKOH / g; molecular weight: 8000) 6 parts, thermosetting fluorocarbon resin (fluorine content: 28%; hydroxyl value: 58 mgKOH / g; molecular weight: 6000) 15 parts, reactive ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyl oxypropoxy) benzophenone) 3 parts, and polyisocyanate compound (-NCO content: 19 wt%) 3 parts.

[0067] Example 4

[0068] ​The difference between this embodiment and Example 1 is that the mass fractions of the crosslinking resin solution raw materials for the protective layer are as follows: 50 parts of 2-butanone, 23 parts of toluene, 8 parts of thermosetting acrylic resin (hydroxyl value: 65 mg KOH / g; molecular weight: 4000), 13 parts of thermosetting fluorocarbon resin (fluorine content: 33%; hydroxyl value: 65 mg KOH / g; molecular weight: 3000), 3 parts of reactive ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyloxypropoxy)benzophenone), and 3 parts of polyisocyanate compound (-NCO content: 19%).

[0069] Example 5

[0070] The difference between this embodiment and Example 1 is that the mass fractions of the crosslinking resin solution raw materials for the protective layer are as follows: 50 parts of 2-butanone, 23 parts of toluene, 4 parts of thermosetting acrylic resin (hydroxyl value: 65 mg KOH / g; molecular weight: 4000), 18 parts of thermosetting fluorocarbon resin (fluorine content: 33%; hydroxyl value: 65 mg KOH / g; molecular weight: 3000), 3 parts of reactive ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyloxypropoxy)benzophenone), and 3 parts of polyisocyanate compound (-NCO content: 19%).

[0071] Example 6

[0072] The difference between this embodiment and Example 1 is that the mass fractions of the crosslinking resin solution raw materials for the protective layer are as follows: 50 parts of 2-butanone, 23 parts of toluene, 4 parts of thermosetting acrylic resin (hydroxyl value: 65 mg KOH / g; molecular weight: 4000), 12 parts of thermosetting fluorocarbon resin (fluorine content: 33%; hydroxyl value: 65 mg KOH / g; molecular weight: 3000), 6 parts of reactive ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyloxypropoxy)benzophenone), and 4 parts of polyisocyanate compound (-NCO content: 19%).

[0073] Example 7

[0074] The difference between this embodiment and Embodiment 1 is that the mass fractions of the protective layer raw materials are as follows: 100 parts of crosslinking resin solution, free radical scavenger ( 3 copies of UV-622 (Tianjin Lianlong New Material Co., Ltd.).

[0075] Example 8

[0076] The difference between this embodiment and Embodiment 1 is that the mass fractions of the protective layer raw materials are as follows: 100 parts of crosslinking resin solution, free radical scavenger ( 1 part of UV-622 (Tianjin Lianlong New Material Co., Ltd.) and 5 parts of thermoplastic resin (MB-2660 Mitsubishi Chemical Corporation).

[0077] Comparative Example 1

[0078] The difference between this comparative example and Example 1 is that the protective layer is not coated.

[0079] Comparative Example 2

[0080] The difference between this comparative example and Example 1 is that the preparation process of the cross-linking resin solution of the protective layer is as follows: 6 parts of thermosetting acrylic resin (hydroxyl value: 55 mgKOH / g; molecular weight: 4000) and 15 parts of thermosetting fluorocarbon resin (hydroxyl value: 65 mgKOH / g; molecular weight: 3000) are dissolved in 50 parts of 2-butanone and 24 parts of toluene, 2.5 parts of polyisocyanate curing agent (-NCO content of 19 wt%) is added, and the reaction is carried out at 60°C with a stirring speed of 1000 r / min for 1 h, 3 parts of ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyl oxypropoxy) benzophenone) is added after ensuring that the isocyanate groups are consumed, and the cross-linking resin solution is obtained.

[0081] Comparative Example 3

[0082] The difference between this comparative example and Example 1 is that the preparation process of the cross-linking resin solution of the protective layer is as follows: 20 parts of thermosetting fluorocarbon resin (hydroxyl value: 65 mgKOH / g; molecular weight: 3000) is dissolved in 50 parts of 2-butanone and 23.5 parts of toluene, 2.5 parts of polyisocyanate curing agent (-NCO content of 19 wt%) is added, and the reaction is carried out at 60°C with a stirring speed of 1000 r / min for 30 min, then 3 parts of ultraviolet absorber (2-hydroxy-4-(2-hydroxy-3-decyl oxypropoxy) benzophenone) is added, and the reaction is continued at 60°C with a stirring speed of 1000 r / min for 30 min, and the cross-linking resin solution is obtained.

[0083] Comparative Example 4

[0084] The difference between this comparative example and Example 1 is that the protective layer is prepared from the following raw materials in parts by weight: 100 parts of cross-linking resin solution, 5 parts of thermoplastic resin (MB-2660, Mitsubishi Chemical Corporation).

[0085] The performance tests of the printed samples of Examples 1-8 and Comparative Examples 1-4 are as follows, and the results are shown in Tables 1-3.

[0086] Printed sample preparation: the self-developed high-weather-resistant yellow ribbon of the company is transferred to the 3M Class V reflective film by using the self-developed traffic printer DTP-1500 of the company, and the protective layer carbon ribbon is simultaneously transferred to the ink layer.

[0087] The light transmittance of the protective layer was tested by the inverse reflection test system before and after the transfer of the protective layer (observation angle 0.2°, incident angle -4°), and the light transmittance was calculated by the following formula:

[0088]

[0089] The ultraviolet transmittance test method refers to GB / T 17032-1997 Test method for ultraviolet transmittance of textiles and fabrics.

[0090] The solvent resistance test refers to the national standard GB-T 23989-2009 Determination of solvent resistance of coatings by wiping.

[0091] The stain resistance test refers to the national standard GB-T 9780-2013 Test method for stain resistance of architectural coatings.

[0092] The adhesion test refers to the national standard GB / T 9286-2021 Crosshatch test for pigmented and clear coatings.

[0093] The weather resistance of the sample was evaluated by the following method:

[0094] The xenon lamp aging condition in the national standard GB / T 18833-2012 Road traffic retroreflective sheeting was used to age the sample in a xenon lamp aging test box for 1800 hours, and the surface was observed for wrinkles, bubbles, cracking and other phenomena. The color difference before and after accelerated aging was measured.

[0095] Table 1 Performance test results of printed samples of Examples 1-4

[0096]

[0097] Table 2 Performance test results of printed samples of Examples 5-8

[0098]

[0099] Table 3 Performance test results of printed samples of Comparative Examples 1-4

[0100]

[0101]

[0102] From the above performance tests, it can be found that the use of thermosetting fluorocarbon resin and thermosetting acrylic resin for crosslinking reaction, and the introduction of alcohol hydroxyl-containing reactive ultraviolet absorber therein, to prepare a crosslinked resin, and the protective layer prepared by the crosslinked resin in combination with thermoplastic acrylic resin and free radical scavenger has excellent weather resistance, solvent resistance and stain resistance.

[0103] Comparative Example 1 The rest of the protective layer formula, the ultraviolet transmittance is much higher than the presence of protective layer formula. From Example 5 and Comparative Example 3 can be seen, reducing the content of thermosetting acrylic resin, the adhesion of protective layer carbon tape and the printing layer is decreased. Comparative Example 1 and Example 4 can be seen, reducing the proportion of thermosetting fluorocarbon resin, its stain resistance performance appears to decline. Comparison of Example 1-7 and Example 8 can be seen, the right amount of free radical scavenger in the protective layer can better improve the weather resistance. Example 1 and Comparative Example 2 can be found that the present application by introducing the reactive ultraviolet absorber into the resin molecules by chemical bonding, compared with the protective layer of directly adding ultraviolet absorber, the protective layer of the present application limits the migration of ultraviolet absorber, so as to have better weather resistance.

[0104] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms is not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, the different embodiments or examples described in the present specification and the features of the different embodiments or examples can be combined and combined by those skilled in the art without contradiction.

[0105] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A thermal transfer protective carbon ribbon having high weather resistance and self-cleaning properties, characterized by, The carbon tape is provided with a protective layer on the substrate; The protective layer is coated by a protective layer coating, and the protective layer coating comprises a crosslinked resin crosslinked by a thermosetting fluorocarbon resin, a thermosetting acrylic resin and an ultraviolet absorber under the action of a crosslinking agent; The thermosetting fluorocarbon resin is FEVE fluorocarbon resin; and / or The thermosetting acrylic resin is a hydroxyl acrylic resin; and / or The ultraviolet absorber is an ultraviolet absorber containing alcoholic hydroxyl groups; The preparation method of the crosslinked resin comprises: reacting the thermosetting fluorocarbon resin and the thermosetting acrylic resin through the crosslinking agent at 50-90°C to form a prepolymer, and then adding the ultraviolet absorber to react at 50-90°C to obtain the crosslinked resin; The mass ratio of the thermosetting fluorocarbon resin, the thermosetting acrylic resin and the ultraviolet absorber is (50-80):(10-40):(10-30); and / or The crosslinking agent is a polyisocyanate crosslinking agent containing at least 3 isocyanate groups on a single crosslinking agent molecule, and the molar ratio of the isocyanate groups of the polyisocyanate crosslinking agent to the total hydroxyl value of the thermosetting fluorocarbon resin, the thermosetting acrylic resin and the ultraviolet absorber is (0.9-2):

1.

2. The thermal transfer protective carbon ribbon having high weather resistance and self-cleaning properties according to claim 1, characterized by, The fluorine content in the thermosetting fluorocarbon resin is 10-45%, the molecular weight of the thermosetting fluorocarbon resin is 1000-20000, and the hydroxyl value is 10-100 mgKOH / g; and / or The molecular weight of the thermosetting acrylic resin is 1000-30000, and the hydroxyl value is 10-100 mgKOH / g.

3. The thermal transfer protective carbon ribbon having high weather resistance and self-cleaning properties according to claim 1, characterized by, The protective layer coating further comprises a thermoplastic resin and a free radical capturing agent; and / or The thermoplastic resin is at least one of an acrylic resin, a chloroethylene-vinyl acetate resin, a chloroethylene-vinyl isobutyl ether resin, a polyurethane resin and an ethylene-vinyl acetate resin; and / or The free radical capturing agent is a hindered amine free radical capturing agent, the molecular weight of the free radical capturing agent is greater than 3000, and the content of the free radical capturing agent in the protective layer coating is 1wt%-20wt%.

4. The thermal transfer ribbon having high weather resistance and self-cleaning properties according to claim 1, wherein, The carbon tape further comprises an adhesive layer, a release layer and a back coating layer, and the adhesive layer, the protective layer, the release layer, the substrate and the back coating layer are sequentially arranged from top to bottom; The substrate is any one of polypropylene, polyethylene terephthalate, polyethylene terephthalate, polyethylene, polyvinyl alcohol and polymethyl methacrylate; The release layer is coated by a release liquid, and the release liquid comprises a bonding resin and wax powder; The adhesive layer is coated by an adhesive liquid, and the adhesive liquid comprises a thermoplastic acrylic resin.

5. The thermal transfer ribbon having high weather resistance and self-cleaning properties according to claim 4, wherein, The particle size D50 of the release liquid is 0.1-0.5μm; and / or The mass ratio of the bonding resin and the wax powder in the release liquid is 3:(7-27); and / or The bonding resin is an ethylene-vinyl acetate resin, and the wax powder is polyethylene wax powder or polytetrafluoroethylene modified polyethylene wax powder; and / or The drop melting point of the wax powder is 90-130°C, and the medium particle size is 3-8μm.

6. The thermal transfer protective carbon ribbon having high weather resistance and self-cleaning properties according to claim 4 or 5, characterized in that, The thickness of the base is 4 to 25 μm, the thickness of the adhesive layer is 0.1 to 1.0 μm, the thickness of the release layer is 0.1 to 2.0 μm, the thickness of the protective layer is 0.5 to 20.0 μm, and the thickness of the back coating layer is 0.2 to 1.0 μm. The thickness of the base is 4 to 25 μm, the thickness of the adhesive layer is 0.1 to 1.0 μm, the thickness of the release layer is 0.1 to 2.0 μm, the thickness of the protective layer is 0.5 to 20.0 μm, and the thickness of the back coating layer is 0.2 to 1.

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