Carbon tape assembly for improved transfer adaptability and clarity and methods of making and transferring same

Abstract

The present application relates to the carbon tape combination of improving the transfer adaptability and the definition and its preparation and transfer method, relate to the thermal transfer printing technical field.The carbon tape combination of the present application includes: first transfer carbon tape, second transfer carbon tape;The first transfer carbon tape includes from bottom to top sequentially arranged back coating, substrate, release layer, dye receiving layer, white light shielding layer, bonding layer;The second transfer carbon tape includes from bottom to top sequentially arranged back coating, substrate, release layer, dye receiving layer.The carbon tape combination prepared by the present application and the matched transfer process can improve the reflectivity of light, thereby improving the color density after sublimation transfer, so that it can have good adhesion and scratch resistance on the surface of various materials, and can greatly improve the transfer definition.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal transfer printing, and in particular to a carbon ribbon combination for improving transfer adaptability and clarity, and a preparation method and transfer method thereof. Background Art

[0002] Sublimation transfer imaging refers to dye sublimation transfer, while resin coating does not transfer. The printed image is very delicate, close to the salt silver effect, but the surface of the substrate must have a special dye-receiving coating, otherwise the dye transfer rate is very low and the image is extremely uneven, which greatly limits the application scenarios of sublimation transfer.

[0003] A common approach is to add a retransfer film, first transferring the dye to it, and then using it and an adhesion-enhancing carbon ribbon to increase the substrate compatibility of sublimation transfer technology. However, this approach significantly increases costs, and multiple thermal transfers can cause dye diffusion, increased color variation, and unclear transferred images. Another approach is to apply a dye-receiving coating to the target substrate. This method increases costs and is only effective for substrates with a dye-receiving coating, and it does not effectively improve the transfer adaptability of the ribbon. Summary of the Invention

[0004] To address the aforementioned technical issues, the present invention provides a carbon ribbon assembly with improved transfer adaptability and clarity, as well as a preparation and transfer method. Thermal transfer of the substrate using the present carbon ribbon assembly and transfer method improves light reflectivity, thereby increasing color density after sublimation transfer. This improves adhesion and scratch resistance on a variety of surfaces, while significantly enhancing transfer clarity.

[0005] The technical solution of the present invention to solve the above technical problems is as follows:

[0006] A first object of the present invention is to provide a carbon ribbon combination that improves transfer adaptability and clarity, the carbon ribbon combination comprising a first transfer carbon ribbon and a second transfer carbon ribbon;

[0007] The first transfer carbon ribbon comprises a first back coating layer, a first substrate, a first release layer, a first dye receiving layer, a white light shielding layer, and an adhesive layer arranged in sequence from bottom to top;

[0008] The second transfer carbon ribbon comprises a second back coating layer, a second substrate, a second release layer, and a second dye receiving layer which are sequentially arranged from bottom to top.

[0009] The beneficial effects of the present invention are as follows: the first carbon ribbon provided can effectively prevent the dye from diffusing into the interior of the paper through the design of the white light-shielding layer, and improve the reflectivity of light, thereby improving the color density after sublimation transfer; through the design of the adhesive layer for materials such as paper, plastic and metal, it can have good adhesion and scratch resistance on the surfaces of various materials.

[0010] The design of cross-printing the first transfer ribbon, the second transfer ribbon and the sublimation ribbon can effectively isolate the three primary color dyes in the image, avoiding the diffusion of the first and second color sequence dyes caused by the heat transfer and the extrusion of the molten resin when printing the second and third color sequences, thereby making the boundary of the transferred image clearer and improving the clarity of the printed image.

[0011] Preferably, the first substrate and the second substrate used in the present invention are both transparent flexible plastic films, including at least one of polypropylene (PP), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyethylene (PE), polyvinyl alcohol (PVA), and polymethyl methacrylate (PMMA).

[0012] Preferably, the substrate is one of PET and PEN.

[0013] Preferably, the thickness of the substrate is 3-12 μm, preferably 4-6 μm.

[0014] Preferably, when the substrate is a PET film, it may be pretreated before coating. Treatment methods include corona discharge, plasma treatment, ozone treatment, flame treatment, primer coating treatment, preheating treatment, dust removal treatment, vapor deposition treatment, alkali treatment, antistatic coating, and other adhesion-promoting treatments. Corona treatment is generally used in the present invention.

[0015] Furthermore, the first back coating layer and the second back coating layer respectively comprise the following raw materials in parts by weight: 9-11 parts of a first resin, 2-4 parts of a polyisocyanate curing agent, 0-1 part of an inorganic filler, and 1-2 parts of a release agent;

[0016] The first release layer and the second release layer respectively comprise the following raw materials in parts by weight: 20-22 parts of the second resin, 1-2 parts of the organic silicone oil, and 1-3 parts of the solid anti-sticking agent;

[0017] The first dye receiving layer and the second dye receiving layer respectively comprise the following raw materials in parts by weight: 20-22 parts of the third resin, 0.3-0.6 parts of the anti-sticking agent, 0.5-5 parts of the curing aid, and 0.5-1 parts of the cross-linking agent;

[0018] The white light-shielding layer comprises the following raw materials in parts by weight: 24-26 parts of a fourth resin, 24-26 parts of a pigment, 0-1 parts of a fluorescent whitening agent, 2-5 parts of a dispersant, 0-2 parts of an antioxidant, and 0.5-2 parts of a light stabilizer;

[0019] The adhesive layer comprises the following raw materials in parts by weight: 18-22 parts of the fifth resin, 0.5-1 part of the crystalline polyester resin, and 0.5-1 part of the polyurethane resin.

[0020] Furthermore, the first resin includes at least one of a thermoplastic resin and a silicone modified thermoplastic resin;

[0021] The inorganic filler includes at least one of talc, kaolin, calcium carbonate, aluminum hydroxide, silicon dioxide, graphite, and boron nitride;

[0022] The release agent includes at least one of phosphate ester, metal soap, silicone oil and surfactant.

[0023] The beneficial effects of adopting the above further scheme are: the function of the back coating layer is to prevent adverse effects such as stickiness or wrinkles caused by heating of the thermal heating head during printing; in order to improve the heat resistance of the back coating layer during the printing process, isocyanate compounds can be added to the resin; in order to maintain the excellent sliding properties of the carbon ribbon during high-speed printing, a release agent needs to be added to the back coating layer; and isocyanate compounds can be further added to improve the heat resistance of the back coating layer during the printing process.

[0024] Preferably, the thermoplastic resin includes polyester resin, polyacrylate resin, polyvinyl acetate resin, styrene acrylate resin, polyurethane resin, polyethylene resin, polypropylene resin and other polyolefin resins, polystyrene resin, polyvinyl chloride resin, polyether resin, polyamide resin, polyimide resin, polyamideimide resin, polycarbonate resin, polyacrylamide resin, polyvinyl chloride resin, polyvinyl butyral resin, polyvinyl acetal resin and other polyvinyl acetal resins and other thermoplastic resins, their silicone modified products, etc.

[0025] More preferred is polyvinyl butyral resin.

[0026] The isocyanate compound is preferably an aromatic isocyanate compound. Examples of the aromatic isocyanate compound include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, toluidine diisocyanate, and p-phenylene diisocyanate.

[0027] Preferably, the inorganic filler is talc or kaolin.

[0028] Preferably, the release agent is a phosphate ester.

[0029] Further, the second resin includes at least one of acrylic resin, polyurethane, vinyl chloride-vinyl acetate, styrene acrylic resin, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, phenolic resin and cellulose acetate;

[0030] The silicone oil includes at least one of epoxy-modified silicone oil, polyester-modified silicone oil, acrylic-modified silicone oil, aromatic-modified silicone oil and phenol-modified silicone oil;

[0031] The solid anti-sticking agent includes at least one of oleamide, erucamide, stearamide, behenamide, ethylenebisoleamide, octadecyl erucamide, and pentaerythritol stearate.

[0032] The beneficial effect of adopting the above further scheme is: the main function of the release layer is to enable the front coating to be normally separated from the substrate without any coating residue during thermal transfer. At the same time, during sublimation transfer, the surface of this layer has good demoulding properties with the ribbon dye receiving layer, avoiding discoloration defects in the dye receiving layer.

[0033] The resin selected for the release layer of the present invention can ensure that the release layer has good demolding properties; the addition of silicone oil can further improve the demolding properties; in addition, the present invention also limits the amount of silicone oil added. Too little silicone oil will lead to insufficient anti-sticking properties, thereby failing to achieve the enhancement effect; too much silicone oil will cause a decrease in dye acceptance; in order to improve the transfer uniformity of the dye and the demolding properties of the coating, a solid anti-sticking agent is also added to the release layer of the present invention.

[0034] Furthermore, the third resin includes at least one of a halogenated resin, a vinyl chloride-vinyl acetate copolymer, a vinyl chloride-modified acrylic resin, and an chloroether resin;

[0035] The anti-sticking agent is a non-reactive silicone oil, and the non-reactive silicone oil is at least one of a benzene ring modified polyether silicone oil and a polyether modified silicone oil;

[0036] The curing aid includes at least one of polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 800, polyethylene glycol 2000, polyethylene glycol 8000, polyethylene glycol 20000 and polypropylene glycol 2000, hydroxy acrylic resin, and trichloroacetic acid;

[0037] The cross-linking agent includes at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

[0038] The beneficial effect of adopting the above further solution is that the present invention provides a dye receiving layer to adhere to the thermal sublimation dye.

[0039] The dye receiving layer of the present invention needs to be coated during preparation. To accelerate the curing of the coating, a certain amount of a hydroxyl-containing curing aid is added to the raw materials, and a cross-linking agent is added to cross-link and cure the coating to a certain extent, so as to further adapt to the high heat resistance required for thermal sublimation high-speed printing. A certain amount of an anti-sticking agent is also added to the dye receiving layer of the present invention to prevent adhesion between the printing layer and the ribbon due to resin melting caused by heating during the printing process. A certain amount of non-reactive silicone oil can provide good smoothness at a high temperature of about 200°C.

[0040] Furthermore, the fourth resin includes at least one of vinyl chloride-vinyl acetate copolymer, chloroether resin, polyester resin, and thermoplastic acrylic resin;

[0041] The pigment includes at least one of rutile titanium dioxide and anatase titanium dioxide;

[0042] The fluorescent whitening agent includes at least one of a stilbene type fluorescent whitening agent, a coumarin type fluorescent whitening agent, a pyrazoline type fluorescent whitening agent, a benzoxazine type fluorescent whitening agent, and a benzimide type fluorescent whitening agent;

[0043] The antioxidant includes at least one of hindered phenol antioxidants, phosphite antioxidants, thio antioxidants, composite antioxidants, and hindered amine antioxidants;

[0044] The light stabilizer includes at least one of salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, triazine ultraviolet absorbers, and hindered amine light stabilizers.

[0045] The beneficial effects of adopting this further embodiment are as follows: the white light-shielding layer provided in the carbon ribbon of the present invention provides a good white base color and excellent interlayer adhesion with the dye-receiving layer. The primary pigment used in the white light-shielding layer of the present invention is at least one of rutile titanium dioxide and anatase titanium dioxide. To enhance the whiteness of the white light-shielding layer, a certain amount of fluorescent brightener is added. Fluorescent brighteners convert ultraviolet light into blue, bluish-violet, or red visible light, producing an optical whitening effect. However, the product will yellow during transfer and use, so additives such as antioxidants, light stabilizers, and ultraviolet absorbers are also required in the coating.

[0046] Furthermore, rutile titanium dioxide with a higher refractive index and better stability is preferred (its refractive index is 2.71, and the higher the refractive index, the better the hiding power). The factory particle size D50 of titanium dioxide is not higher than 0.5μm. After dispersion and grinding, the proportion of titanium dioxide particle size distribution in the range of 0.2-0.4μm is required to be not less than 80% (when the particle size of titanium dioxide is half the wavelength of visible light, its hiding power is best, and the wavelength of visible light is 380nm-780nm).

[0047] Furthermore, the ratio of resin to titanium dioxide is 1:0.5-4, preferably 1:1-2.

[0048] The beneficial effect of adopting the above further solution is: in order to ensure hiding power, the titanium dioxide content should theoretically be as high as possible, but the connectivity of the coating must also be guaranteed. By adding resin and titanium dioxide within the above limited range, the hiding power and coating connectivity are optimized.

[0049] Preferably, during transfer printing, hollow glass microspheres with a D50 of 1-5 μm can be added to the paper substrate in an amount of 2-10 phr of the fourth resin, which can serve to isolate heat and buffer pressure during printing.

[0050] Furthermore, non-crystalline polyester resin may be added to the white light-shielding layer to ensure interlayer adhesion between the white light-shielding layer and the adhesive layer and the dye-receiving layer.

[0051] Furthermore, the non-crystalline polyester resin preferably has a glass transition temperature (Tg) of 50° C. or higher and 80° C. or lower, and a molecular weight of 3,000 or higher and 25,000 or lower.

[0052] Furthermore, the fifth resin includes at least one of polyester resin, polyurethane resin (TPU), chloroether resin, and acrylic resin.

[0053] Preferably, a promoter may be added to the adhesive layer, and the promoter includes at least one of a silane coupling agent, a titanate coupling agent, a zirconate coupling agent, a zirconium-aluminate organic compound, a chlorinated polyolefin, a chromium complex, and a phosphorus-containing compound.

[0054] The beneficial effect of adopting this further solution is that the adhesive layer primarily serves to provide adhesion between the entire coating layer and the target substrate during transfer. Therefore, to improve adhesion between the adhesive layer and the target substrate and interlayer adhesion with the white barrier layer, a fifth resin may be added to the adhesive layer.

[0055] Furthermore, a crystalline polyester resin may be added to the adhesive layer to enhance the fluidity of the coating resin when the retransfer film is transferred to the surface of the target substrate, especially a paper substrate, so that the resin can penetrate into the pores on the surface of the substrate. The softening point of the crystalline polyester resin is -70~10°C, the melting point is lower than 110°C, and the melt viscosity is not higher than 1000dPa.s.

[0056] Preferably, the fifth resin is a combination of a chloroether resin and a polyester resin having a softening point of 40-80° C. Since chloroether resins are relatively brittle and have poor curling resistance, polyurethane resin (TPU) is generally added to ensure good toughness of the base coat.

[0057] Preferably, in order to improve the adhesion of the carbon ribbon to the metal, a certain amount of adhesion promoter may be added, preferably a combination of a silane coupling agent and a titanate coupling agent, and an epoxy silane coupling agent is preferably used as the silane coupling agent.

[0058] Furthermore, the thickness of the first back coating layer is 0.4μm-1.2μm; the thickness of the second back coating layer is 0.4μm-1.2μm; the thickness of the first substrate is 3-12μm; the thickness of the second substrate is 3-12μm; the thickness of the first release layer is 0.05-0.5μm; the thickness of the second release layer is 0.05-0.5μm; the thickness of the first dye receiving layer is 1-10μm; the thickness of the second dye receiving layer is 1-10μm; the thickness of the white shading layer is 1-5μm; and the thickness of the adhesive layer is 0.8-1.2μm.

[0059] A second object of the present invention is to provide a method for preparing a carbon ribbon assembly that improves transfer adaptability and clarity. The method for preparing a first transfer carbon ribbon is as follows:

[0060] S1: liquid preparation: first demoulding liquid: dissolve the second resin in a solvent, then add silicone oil and a solid anti-sticking agent and mix and dissolve them together to prepare a first demoulding liquid for standby use; first dye receiving liquid: dissolve the third resin in a solvent, then add an anti-sticking agent, a curing aid, and a cross-linking agent and mix and dissolve them together to prepare a first dye receiving liquid for standby use; white light-shielding liquid: dissolve the fourth resin in a solvent, then add a dispersant and a pigment and grind them, and after the grinding is completed, add an antioxidant, a light stabilizer, and a fluorescent whitening agent and mix and dissolve them together to prepare a white light-shielding liquid for standby use; bonding liquid: dissolve the fifth resin in a solvent, then add a crystalline polyester resin and a polyurethane resin and mix and dissolve them together to prepare a bonding liquid for standby use; first back coating liquid: dissolve the first resin in a solvent, then add a polyisocyanate curing agent, an inorganic filler, and a demoulding agent and mix and dissolve them together to prepare a first back coating liquid for standby use;

[0061] S2: applying corona to both sides of the first substrate;

[0062] S3: Coating: Apply a first back coating liquid to one side of the first substrate subjected to corona discharge, and then dry to form a first back coating layer for standby use; then apply a first release liquid to the side of the first substrate away from the first back coating layer, and then dry to form a first release layer; then apply a first dye receiving liquid to the side of the first release layer away from the first substrate, and then dry to form a first dye receiving layer; apply a white light-shielding liquid to the side of the first dye receiving layer away from the first substrate, and then dry to form a white light-shielding layer; apply a bonding liquid to the side of the white light-shielding layer away from the first substrate, and then dry to form a bonding layer; thus, a first transfer carbon ribbon is obtained;

[0063] The preparation method of the second transfer carbon ribbon is as follows: S1: preparing a liquid: a second release liquid: dissolving the second resin in a solvent, then adding silicone oil and a solid anti-sticking agent, mixing and dissolving them together to prepare a second release liquid, which is set aside; a second dye receiving liquid: dissolving the third resin in a solvent, then adding an anti-sticking agent, a curing aid, and a cross-linking agent, mixing and dissolving them together to prepare a second dye receiving liquid, which is set aside; a second back coating liquid: dissolving the first resin in a solvent, then adding a polyisocyanate curing agent, an inorganic filler, and a release agent, mixing and dissolving them together to prepare a second back coating liquid, which is set aside;

[0064] S2: applying corona to both sides of the second substrate;

[0065] S3: Coating: Coat the second back coating liquid on one of the corona-charged sides of the second substrate, and then dry it to form a second back coating layer for standby use; then coat the second release liquid on the side of the second substrate away from the second back coating layer, and then dry it to form a second release layer; then coat the second dye-receiving liquid on the side of the second release layer away from the second substrate, and then dry it to form a second dye-receiving layer, thereby obtaining a second transfer carbon ribbon.

[0066] A third object of the present invention is to provide a transfer method for a carbon ribbon assembly that improves transfer adaptability and clarity, wherein the transfer method comprises:

[0067] Before the sublimation transfer, a first transfer carbon ribbon is provided, and the dye receiving layer and the white light shielding coating of the first transfer carbon ribbon are simultaneously transferred to the surface of the substrate by thermal transfer to form a first transfer coating;

[0068] Then print the yellow thermal sublimation ribbon, then transfer the coating of the second transfer carbon ribbon to the first transfer coating surface to obtain the second transfer coating surface A, then print the magenta thermal sublimation ribbon, then transfer the coating of the second transfer carbon ribbon to the second transfer coating surface A again to obtain the second transfer coating surface B, and finally print the cyan thermal sublimation ribbon to form the final image.

[0069] The beneficial effect of the present invention is that: through the design of cross-printing of the first transfer carbon ribbon, the second transfer carbon and the sublimation carbon ribbon, the present invention can effectively isolate the three primary color dyes in the image, avoiding the diffusion of the dyes of the first and second color sequences caused by the transfer of heat and the extrusion of the molten resin when the second and third color sequences are printed, thereby making the boundary of the image after transfer clearer, thereby improving the clarity of the printed image. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 A structural diagram of a first transfer carbon ribbon according to an embodiment of the present invention;

[0071] Figure 2 A structural diagram of a second transfer carbon ribbon according to an embodiment of the present invention;

[0072] Figure 3 This is a diagram of the transfer process of Example 4 of the present invention.

[0073] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0074] 1-adhesive layer, 2-white light-shielding layer, 3-first dye-receiving layer, 4-first release layer, 5-first substrate, 6-first back coating layer, 7-second dye-receiving layer, 8-second release layer, 9-second substrate, 10-second back coating layer. DETAILED DESCRIPTION

[0075] The principles and features of the present invention are described below. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in this field or the product instructions are used. Where the manufacturers of the reagents or instruments used are not specified, they are all conventional products that can be purchased through regular channels.

[0076] Example 1: Preparation of carbon ribbon assembly

[0077] (1) Preparation of the first transfer ribbon:

[0078] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0079] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0080] White shading liquid: dissolve 15 parts of polyester resin (220, Tg: 53, Mn: 3000, Toyobo) and 10 parts of thermoplastic acrylic resin (BR-83, Tg: 105℃, Mn: 40000, Mitsubishi) in 32.6 parts of 2-butanone and 32.6 parts of toluene, then add 3 parts of dispersant (710S Euka), and after uniform dispersion, add 25 parts of titanium dioxide (R706 DuPont) and grind to a particle size of about 0.2-0.4 μm. After grinding, add 0.5 parts of antioxidant (1010 BASF), 0.5 parts of antioxidant (168 BASF), 0.5 parts of ultraviolet light absorber (Tinuvin 1130 BASF), 0.5 parts of hindered amine light stabilizer (Tinuvin 123 BASF), and 0.3 parts of fluorescent brightener (OB-1 Lingrui Chemical) and mix and dissolve them together to make a white shading liquid for later use;

[0081] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000, Mitsubishi) and 10 parts of chloroether resin (MP-25, BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene. Then add 1 part of crystalline polyester resin (GM920, Tg: -60°C, Mn: 30,000, Toyobo) and 1 part of polyurethane resin (TPU-5778, Tg: 31.1, Lubrizol) and mix and dissolve them to make an adhesive solution for later use.

[0082] First back coating liquid: dissolve 10 parts of polyvinyl butyral resin (S-LEC Second H-6 Japan Sekisui Chemical) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80 Second Japan Asahi Chemical), 0.5 parts of silicone oil (KF-965-100cs Shin-Etsu Silicone), 0.6 parts of phosphate ester (MO First-3PK-70 Jiangsu Hai'an Petrochemical Plant), 0.6 parts of talc (HY-T First 05 Haiyang Powder) and mix and dissolve them to make the first back coating liquid for later use;

[0083] S2: Using a 4.5 μm PET film as the first substrate 5, corona discharge is applied to both sides of the first substrate 5;

[0084] S3: Coating: Coat the first back coating liquid on the corona-charged side of the first substrate 5 with a coating thickness of 0.4 μm, and then dry to form a first back coating layer 6 for standby use; then coat the first release liquid on the side of the first substrate 5 away from the first back coating layer 6 with a coating thickness of 0.5 μm, and then dry to form a first release layer 4; then coat the first dye receiving liquid on the side of the first release layer 4 away from the first substrate 5 with a coating thickness of 1.5 μm, and then dry to form a first dye receiving layer 3; coat the white shading liquid on the side of the first dye receiving layer 3 away from the first substrate 5 with a coating thickness of 1.5 μm, and then dry to form a white shading layer 2; coat the adhesive liquid on the side of the white shading layer 2 away from the first substrate 5 with a coating thickness of 1 μm, and then dry to form an adhesive layer 1; that is, the first transfer carbon ribbon is obtained.

[0085] Preparation of the second carbon ribbon:

[0086] Compared with the preparation of the first transfer carbon ribbon, the only missing parts are the preparation of the white light-shielding layer 2 and the adhesive layer 1 .

[0087] S1: Prepare the second mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the second mold release liquid, and set aside;

[0088] Second dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve them together to prepare the second dye-receiving solution for later use.

[0089] Second back coating liquid: Dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05 Haiyang Powder) and mix and dissolve them to prepare the second back coating liquid for later use;

[0090] S3: Coating: Coat the second back coating liquid on the corona-charged side of the second substrate 9 with a coating thickness of 0.4 μm, and then dry to form a second back coating layer 10 for standby use; then coat the second release liquid on the side of the second substrate 9 away from the second back coating layer 10 with a coating thickness of 0.5 μm, and then dry to form a second release layer 8; then coat the second dye-receiving liquid on the side of the second release layer 8 away from the second substrate 9 with a coating thickness of 1.5 μm, and then dry to form a second dye-receiving layer 7; that is, the second transfer carbon ribbon is obtained.

[0091] Example 2: Preparation of carbon ribbon assembly

[0092] Preparation of the first transfer ribbon:

[0093] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0094] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0095] White shading liquid: Dissolve 15 parts of polyester resin (220, Tg: 53, Mn: 3000, Toyobo) and 10 parts of acrylic resin (BR-83, Tg: 105℃, Mn: 40000, Mitsubishi) in 32.6 parts of 2-butanone and 32.6 parts of toluene, then add 3 parts of dispersant (710S Euka), and after uniform dispersion, add 25 parts of titanium dioxide (R706 DuPont) and grind to a particle size of about 0.2-0.4 μm. After grinding, add 0.5 parts of antioxidant (1010 BASF), 0.5 parts of antioxidant (168 BASF), 0.5 parts of ultraviolet light absorber (Tinuvin 1130 BASF), 0.5 parts of hindered amine light stabilizer (Tinuvin 123 BASF), and 0.3 parts of fluorescent brightener (OB-1 Lingrui Chemical) and mix and dissolve them together to make a white shading liquid for later use;

[0096] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000, Mitsubishi) and 10 parts of chloroether resin (VC-40, BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene. Then add 1 part of crystalline polyester resin (GA6400, Tg: -20°C, Mn: 30,000, Toyobo), 1 part of polyurethane resin (901H, Wanhua Chemical), 1 part of silane coupling agent (KBM-403 Shin-Etsu Silicone), and 1 part of titanate coupling agent (LA Hi-4, Kaishida Chemical), mix and dissolve together to make an adhesive solution for later use.

[0097] First back coating liquid: Dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs, Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05, Haiyang Powder) and mix and dissolve them to prepare the first back coating liquid for later use;

[0098] S2: Same as Example 1;

[0099] S3: Same as Example 1.

[0100] Preparation of the second transfer carbon ribbon: the same as in Example 1.

[0101] Example 3: Preparation of carbon ribbon assembly

[0102] Preparation of the first transfer ribbon:

[0103] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0104] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0105] White light-shielding liquid: 5 parts of hydroxy-modified acrylic resin (SGR-016A, Tg: 50, Mn: 80000 Changhao) and 15 parts of polyester resin (220, Tg: 53, Mn: 3000 Toyobo) were dissolved in 32.6 parts of 2-butanone and 32.6 parts of toluene, and then 3 parts of dispersant (710S Youka) were added. After uniform dispersion, 0.6 parts of hollow glass microspheres (D50 = 2μm, Zhongke Huaxing New Materials) and 15 parts of titanium dioxide (R706 DuPont) with a particle size of 3μm were added and ground to a particle size of about 0.2-0.4um. After grinding, 0.5 parts of antioxidant (B900 BASF), 0.5 parts of ultraviolet light absorber (Tinuvin 1130 BASF), and 0.5 parts of hindered amine light stabilizer (Tinuvin 123 BASF), 0.3 parts of fluorescent brightener (OB-1 Lingrui Chemical) were mixed and dissolved together to make a white light-shielding liquid for later use;

[0106] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000, Mitsubishi) and 10 parts of chloroether resin (MP-25, BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene. Then add 1 part of crystalline polyester resin (GM920, Tg: -60°C, Mn: 30,000, Toyobo) and 1 part of polyurethane resin (TPU-5778, Tg: 31.1, Lubrizol) and mix and dissolve them to make an adhesive solution for later use.

[0107] First back coating liquid: Dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs, Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05, Haiyang Powder) and mix and dissolve them to prepare the first back coating liquid for later use;

[0108] S2: Same as Example 1;

[0109] S3: Same as Example 1.

[0110] Preparation of the second transfer carbon ribbon: the same as in Example 1.

[0111] Comparative Example 1: Preparation of carbon ribbon combination

[0112] Compared with Example 1, the carbon ribbon combination prepared in this comparative example lacks the preparation of the second transfer carbon ribbon, and the first transfer carbon ribbon is consistent with that in Example 1.

[0113] Comparative Example 2: Preparation of carbon ribbon combination

[0114] Compared with Example 1, the first transfer carbon ribbon in this comparative example does not have a white light-shielding layer. The remaining raw materials, preparation method, and second transfer carbon ribbon are the same as those in Example 1. The preparation steps S1 and S3 of the first transfer carbon ribbon are as follows:

[0115] Preparation of the first transfer ribbon:

[0116] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0117] Dye receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the dye receiving solution for later use.

[0118] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000, Mitsubishi) and 10 parts of chloroether resin (MP-25, BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene. Then add 1 part of crystalline polyester resin (GM920, Tg: -60°C, Mn: 30,000, Toyobo) and 1 part of polyurethane resin (TPU-5778, Tg: 31.1, Lubrizol) and mix and dissolve them to make an adhesive solution for later use.

[0119] First back coating liquid: Dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs, Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-T05, Haiyang Powder) and mix and dissolve them to prepare the first back coating liquid for later use;

[0120] S3: Coating: Coat the first back coating liquid on the corona-charged side of the first substrate 5 with a coating thickness of 0.4 μm, and then dry to form a first back coating layer 6 for use; then coat the first release liquid on the side of the first substrate 5 away from the first back coating layer 6 with a coating thickness of 0.5 μm, and then dry to form a first release layer 4; then coat the first dye-receiving liquid on the side of the first release layer 4 away from the first substrate 5 with a coating thickness of 1.5 μm, and then dry to form a first dye-receiving layer 3; coat the adhesive liquid on the side of the first dye-receiving layer 3 away from the first substrate 5 with a coating thickness of 1 μm, and then dry to form an adhesive layer 1; that is, the first transfer carbon ribbon is obtained.

[0121] Comparative Example 3: Preparation of carbon ribbon combination

[0122] Compared with Example 1, the first transfer carbon ribbon in this comparative example does not have the adhesive layer 1. The remaining raw materials, preparation method, and second transfer carbon ribbon are the same as those in Example 1. The preparation steps S1 and S3 of the first transfer carbon ribbon are as follows:

[0123] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0124] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0125] White shading liquid: Dissolve 15 parts of polyester resin (220, Tg: 53, Mn: 3000, Toyobo) and 10 parts of acrylic resin (BR-83, Tg: 105℃, Mn: 40000, Mitsubishi) in 32.6 parts of 2-butanone and 32.6 parts of toluene, then add 3 parts of dispersant (710S Euka), and after uniform dispersion, add 25 parts of titanium dioxide (R706 DuPont) and grind to a particle size of about 0.2-0.4 μm. After grinding, add 0.5 parts of antioxidant (1010 BASF), 0.5 parts of antioxidant (168 BASF), 0.5 parts of ultraviolet light absorber (Tinuvin 1130 BASF), 0.5 parts of hindered amine light stabilizer (Tinuvin 123 BASF), and 0.3 parts of fluorescent brightener (OB-1 Lingrui Chemical) and mix and dissolve them together to make a white shading liquid for later use;

[0126] Back coating liquid: Dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene. Then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05 Haiyang Powder) and mix and dissolve them to make a back coating liquid for later use.

[0127] S3: Coating: Coat the first back coating liquid on the corona-charged side of the first substrate 5 with a coating thickness of 0.4 μm, and then dry to form a first back coating layer 6 for standby use; then coat the first release liquid on the side of the first substrate 5 away from the first back coating layer 6 with a coating thickness of 0.5 μm, and then dry to form a first release layer 4; then coat the first dye receiving liquid on the side of the first release layer 4 away from the first substrate 5 with a coating thickness of 1.5 μm, and then dry to form a first dye receiving layer 3; coat the white shading liquid on the side of the first dye receiving layer 3 away from the first substrate 5 with a coating thickness of 1.5 μm, and then dry to form a white shading layer 2, thereby obtaining the first transfer carbon ribbon.

[0128] Comparative Example 4: Preparation of carbon ribbon combination

[0129] Compared with Example 1, in this comparative example, no antioxidant, ultraviolet light absorber, hindered amine light stabilizer, or fluorescent brightener was added to the white light-shielding layer 2 of the first transfer carbon ribbon. The remaining raw materials, preparation method, and second transfer carbon ribbon were the same as those in Example 1. The preparation step S1 of the first transfer carbon ribbon is as follows:

[0130] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0131] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0132] White light-shielding liquid: Dissolve 15 parts of polyester resin (220, Tg: 53, Mn: 3000, Toyobo) and 10 parts of acrylic resin (BR-83, Tg: 105℃, Mn: 40000, Mitsubishi) in 32.6 parts of 2-butanone and 32.6 parts of toluene. Then add 3 parts of dispersant (710S Euka). After uniform dispersion, add 25 parts of titanium dioxide (R706 DuPont) and grind to a particle size of about 0.2-0.4 μm to make a white light-shielding liquid for later use.

[0133] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000, Mitsubishi) and 10 parts of chloroether resin (MP-25, BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene. Then add 1 part of crystalline polyester resin (GM920, Tg: -60°C, Mn: 30,000, Toyobo) and 1 part of polyurethane resin (TPU-5778, Tg: 31.1, Lubrizol) and mix and dissolve them to make an adhesive solution for later use.

[0134] First back coating liquid: dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05 Haiyang Powder) and mix and dissolve them together to make the first back coating liquid for later use.

[0135] Comparative Example 5: Preparation of carbon ribbon combination

[0136] Compared with Example 1, in this comparative example, no crystalline polyester resin or polyurethane resin was added to the adhesive layer 1 of the first transfer carbon ribbon. The remaining raw materials, preparation method, and second transfer carbon ribbon were the same as those in Example 1. The preparation step S1 of the first transfer carbon ribbon is as follows:

[0137] S1: Prepare the first mold release liquid: dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical) and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene, then add 0.5 parts of aromatic modified silicone oil (BYK-323 BYK Chemical), 0.5 parts of octadecyl erucamide, and 0.5 parts of pentaerythritol stearate, mix and dissolve together to prepare the first mold release liquid, and set aside;

[0138] First dye-receiving solution: Dissolve 20 parts of vinyl chloride-vinyl acetate copolymer (CP-450 Hanwha Chemical), 0.5 parts of aromatic modified silicone resin (KF-1005 Shin-Etsu Silicone), 1 part of phenolic resin (240L Yoshida Chemical), and 1 part of ethylene-vinyl acetate copolymer (40W Mitsui Chemicals) in 38 parts of 2-butanone and 38 parts of toluene. Then add 0.5 parts of diphenylmethane diisocyanate (WANNATE® MDI-50F Wanhua Chemical) and 1 part of polyethylene glycol-600, mix and dissolve, and prepare the first dye-receiving solution for later use.

[0139] White shading liquid: dissolve 15 parts of polyester resin (220, Tg: 53, Mn: 3000, Toyobo) and 10 parts of acrylic resin (BR-83, Tg: 105℃, Mn: 40000, Mitsubishi) in 32.6 parts of 2-butanone and 32.6 parts of toluene, then add 3 parts of dispersant (710S Euka), and after uniform dispersion, add 25 parts of titanium dioxide (R706 DuPont) and grind to a particle size of about 0.2-0.4um. After grinding, add 0.5 parts of antioxidant (1010 BASF), 0.5 parts of antioxidant (168 BASF), 0.5 parts of ultraviolet light absorber (Tinuvin 1130 BASF), 0.5 parts of hindered amine light stabilizer (Tinuvin 123 BASF), and 0.3 parts of fluorescent brightener (OB-1 Lingrui Chemical) and mix and dissolve them together to make a white shading liquid for later use;

[0140] Adhesive solution: Dissolve 10 parts of acrylic resin (BR-80, Tg: 104°C, Mn: 100,000 Mitsubishi) and 10 parts of chloroether resin (MP-25 BASF) in 39.5 parts of 2-butanone and 39.5 parts of toluene to prepare an adhesive solution for later use.

[0141] First back coating liquid: dissolve 10 parts of polyvinyl butyral resin (S-LEC BH-6, Sekisui Chemical, Japan) in 42.65 parts of 2-butanone and 42.65 parts of toluene, then add 3 parts of polyisocyanate curing agent (TMHG-80B, Asahi Chemical, Japan), 0.5 parts of silicone oil (KF-965-100cs Shin-Etsu Silicone), 0.6 parts of phosphate ester (MOA-3PK-70, Jiangsu Hai'an Petrochemical Plant), and 0.6 parts of talc (HY-TA05 Haiyang Powder) and mix and dissolve them together to make the first back coating liquid for later use.

[0142] Example 4: Transfer process

[0143] Before the sublimation transfer, a first transfer carbon ribbon is provided, and the dye receiving layer and the white light shielding coating of the first transfer carbon ribbon are simultaneously transferred to the surface of the substrate by thermal transfer to form a first transfer coating;

[0144] Then print the yellow thermal sublimation ribbon, then transfer the coating of the second transfer carbon ribbon to the first transfer coating surface to obtain the second transfer coating surface A, then print the magenta thermal sublimation ribbon, then transfer the coating of the second transfer carbon ribbon to the second transfer coating surface A again to obtain the second transfer coating surface B, and finally print the cyan thermal sublimation ribbon to form the final image.

[0145] Performance testing:

[0146] The carbon ribbon combinations prepared in Examples 1-3 and Comparative Examples 1-5 were tested for color density, first transfer carbon ribbon transfer adaptability, substrate adhesion, and clarity. Figure 1 As shown, the second transfer ribbon is as Figure 2 As shown, the test method is as follows:

[0147] (1) Color density test

[0148] A printer (DNP DS620, Dai Nippon Printing) was used to print the ribbons prepared in Examples 1-3 and Comparative Examples 1-5, respectively. The transfer method of Example 4 (e.g. Figure 3 (As shown), print a 256-grayscale pattern on a white sticker in linear mode. After printing, use an X-Rite i1-PRO3 colorimeter to measure the pattern's color density. The judging criteria are as follows:

[0149] (2) First transfer ribbon transfer adaptability test:

[0150] A printer (DNP DS620, Dai Nippon Printing) was used to print a 256-grayscale image on coated paper using the ribbon combinations prepared in Examples 1-3 and Comparative Examples 1-5, respectively, using the transfer method described in Example 4. The print mode was linear. After printing, the transfer degree was measured.

[0151] (3) Substrate adhesion test

[0152] A printer (DNP DS620, Dai Nippon Printing) was used with the ribbon combinations prepared in Examples 1-3 and Comparative Examples 1-5, respectively, using the transfer method described in Example 4 to print 256 grayscale images on PP synthetic paper, steel plate paper, rice paper, silk paper, white cardboard, aluminum alloy plate, and matte silver paper, respectively. The printing mode was set to linear. After printing, the adhesion was tested using 3M tape.

[0153] (4) Clarity test

[0154] A printer (DNP DS620, Dai Nippon Printing) was used to print a 1-pixel black line on white cardboard using the carbon ribbon combinations prepared in Examples 1-3 and Comparative Examples 1-5, respectively, and the transfer method of Example 4. After printing, the transfer clarity was tested.

[0155] The evaluation criteria are shown in Table 1:

[0156] Table 1: Evaluation criteria

[0157]

[0158] The results are shown in Table 2:

[0159] Table 2: Evaluation results

[0160]

[0161] From Table 1, we can get:

[0162] (1) The comprehensive performance of the carbon ribbon combinations of Examples 1-3 is better than that of the carbon ribbon combinations of Comparative Examples 1-5 in the thermal transfer process. Except for the relatively poor color density and adhesion of the substrates on silk cloth and aluminum alloy plate, the other performances of the carbon ribbon combinations of Examples 1-3, such as clarity, transfer adaptability, and adhesion of the substrates (rice paper, PP synthetic paper, steel plate paper, silk paper, white cardboard, and sub-silver paper), are all A.

[0163] (2) The thermal transfer clarity of the ribbon combinations of Comparative Examples 1-5 was poor. Comparative Example 1, which lacked the second transfer ribbon, received a C rating for clarity. Compared to Example 1, the lack of the second transfer ribbon resulted in decreased color density and clarity. The present invention significantly improves transfer clarity in the thermal transfer process through the ribbon combination and the accompanying transfer process.

[0164] (3) Compared with Example 1, the first transfer carbon ribbon of Comparative Example 2 lacks a white light-shielding layer, and its clarity is reduced from A to B, and its color density is also reduced to C; while the white light-shielding layer of Comparative Example 4 does not contain antioxidants, ultraviolet light absorbers, hindered amine light stabilizers, and fluorescent whitening agents, and its color density is poor and its clarity is also reduced. It can be seen that the white light-shielding layer in the embodiment of the present invention is added with antioxidants, ultraviolet light absorbers, hindered amine light stabilizers, fluorescent whitening agents and other raw materials, which can better achieve optical whitening effect, reduce the yellowing of the product during transfer and use, and thus improve the clarity and color density in thermal transfer.

[0165] (4) In Comparative Example 3, the adhesive layer of the first transfer carbon ribbon was removed, and all properties were reduced. In Comparative Example 5, although the adhesive layer was not removed, the crystalline polyester resin and polyurethane resin were not added to the adhesive layer, and its various properties were even worse than those of Comparative Example 3. In the embodiments of the present invention, crystalline polyester resin and polyurethane resin were added to enhance the fluidity of the coating resin when the retransfer film was transferred to the surface of the target substrate (especially paper substrate), allowing the resin to penetrate into the pores on the substrate surface, improving the adhesion between the adhesive layer and the target substrate and the interlayer adhesion with the white barrier layer, thereby improving the adhesion performance of the entire coating layer to the target substrate when transferred to the target substrate.

[0166] In summary, the first transfer ribbon provided by the present invention, through the design of a white light-shielding layer, effectively blocks dye diffusion into the paper, improves light reflectivity, and thus enhances color density after sublimation transfer. The design of the adhesive layer, tailored to materials such as paper, plastic, and metal, ensures excellent adhesion and scratch resistance on a variety of surfaces. The cross-printing design of the first transfer ribbon, the second transfer ribbon, and the sublimation ribbon effectively isolates the three primary colors within the image, preventing the diffusion of the first and second color sequence dyes caused by heat transfer and extrusion of molten resin during the printing of the second and third color sequences. This results in a clearer boundary between the transferred image and improves the clarity of the printed image.

[0167] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A carbon ribbon combination that improves transfer adaptability and clarity, characterized in that: The carbon ribbon combination includes a first transfer carbon ribbon and a second transfer carbon ribbon; The first transfer carbon ribbon comprises a first back coating layer, a first substrate, a first release layer, a first dye receiving layer, a white light shielding layer, and an adhesive layer arranged in sequence from bottom to top; The second transfer carbon ribbon comprises a second back coating layer, a second substrate, a second release layer, and a second dye receiving layer arranged in sequence from bottom to top; The first back coating layer and the second back coating layer respectively comprise the following raw materials in parts by weight: 9-11 parts of a first resin, 2-4 parts of a polyisocyanate curing agent, 0-1 part of an inorganic filler, and 1-2 parts of a release agent; The first release layer and the second release layer respectively comprise the following raw materials in parts by weight: 20-22 parts of the second resin, 1-2 parts of the organic silicone oil, and 1-3 parts of the solid anti-sticking agent; The first dye receiving layer and the second dye receiving layer respectively comprise the following raw materials in parts by weight: 20-22 parts of the third resin, 0.3-0.6 parts of the anti-sticking agent, 0.5-5 parts of the curing aid, and 0.5-1 parts of the cross-linking agent; The white light-shielding layer comprises the following raw materials in parts by weight: 24-26 parts of a fourth resin, 24-26 parts of a pigment, 0-1 parts of a fluorescent whitening agent, 2-5 parts of a dispersant, 0-2 parts of an antioxidant, and 0.5-2 parts of a light stabilizer; The adhesive layer comprises the following raw materials in parts by weight: 18-22 parts of the fifth resin, 0.5-1 part of the crystalline polyester resin, and 0.5-1 part of the polyurethane resin; The transfer method of the carbon ribbon combination for improving transfer adaptability and clarity is specifically as follows: Before the sublimation transfer, a first transfer carbon ribbon is provided, and a first dye receiving layer and a white light shielding layer of the first transfer carbon ribbon are simultaneously transferred to the surface of the substrate by thermal transfer to form a first transfer coating; Then print the yellow thermal sublimation ribbon, transfer the coating of the second transfer carbon ribbon to the first transfer coating surface to obtain the second transfer coating surface A, then print the magenta thermal sublimation ribbon, and then transfer the coating of the second transfer carbon ribbon to the second transfer coating surface A again to obtain the second transfer coating surface B, and finally print the cyan thermal sublimation ribbon to form the final image.

2. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The first resin includes at least one of a thermoplastic resin and a silicone modified thermoplastic resin; The inorganic filler includes at least one of talc, kaolin, calcium carbonate, aluminum hydroxide, silicon dioxide, graphite, and boron nitride; The release agent includes at least one of phosphate ester, metal soap, silicone oil and surfactant.

3. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The second resin comprises at least one of acrylic resin, polyurethane, vinyl chloride-vinyl acetate, styrene acrylic resin, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, phenolic resin and cellulose acetate; The silicone oil includes at least one of epoxy-modified silicone oil, polyester-modified silicone oil, acrylic-modified silicone oil, aromatic-modified silicone oil and phenol-modified silicone oil; The solid anti-sticking agent includes at least one of oleamide, erucamide, stearamide, behenamide, ethylenebisoleamide, octadecyl erucamide, and pentaerythritol stearate.

4. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The third resin includes at least one of a halogenated resin, a vinyl chloride-vinyl acetate copolymer, a vinyl chloride-modified acrylic resin, and an chloroether resin; The anti-sticking agent is non-reactive silicone oil, and the non-reactive silicone oil is at least one of aromatic modified silicone oil and polyether modified silicone oil; The curing aid includes at least one of polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 800, polyethylene glycol 2000, polyethylene glycol 8000, polyethylene glycol 20000 and polypropylene glycol 2000, hydroxy acrylic resin, and trichloroacetic acid; The cross-linking agent includes at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

5. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The fourth resin includes at least one of vinyl chloride-vinyl acetate copolymer, chloroether resin, polyester resin, and thermoplastic acrylic resin; The pigment includes at least one of rutile titanium dioxide and anatase titanium dioxide; The fluorescent whitening agent includes at least one of a stilbene type fluorescent whitening agent, a coumarin type fluorescent whitening agent, a pyrazoline type fluorescent whitening agent, a benzoxazine type fluorescent whitening agent, and a benzimide type fluorescent whitening agent; The antioxidant includes at least one of hindered phenol antioxidants, phosphite antioxidants, thio antioxidants, composite antioxidants, and hindered amine antioxidants; The light stabilizer includes at least one of salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, triazine ultraviolet absorbers, and hindered amine light stabilizers.

6. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The fifth resin includes at least one of polyester resin, polyurethane resin, chloroether resin, and acrylic resin.

7. The carbon ribbon assembly for improving transfer adaptability and clarity according to claim 1, characterized in that: The thickness of the first back coating layer is 0.4μm-1.2μm; the thickness of the second back coating layer is 0.4μm-1.2μm; the thickness of the first substrate is 3-12μm; the thickness of the second substrate is 3-12μm; the thickness of the first release layer is 0.05-0.5μm; the thickness of the second release layer is 0.05-0.5μm; the thickness of the first dye receiving layer is 1-10μm; the thickness of the second dye receiving layer is 1-10μm; the thickness of the white shading layer is 1-5μm; and the thickness of the bonding layer is 0.8-1.2μm.

8. A method for preparing a carbon ribbon assembly with improved transfer adaptability and clarity according to any one of claims 1 to 7, characterized in that: The preparation method of the first transfer carbon ribbon is as follows: S1: liquid preparation: first demoulding liquid: dissolve the second resin in a solvent, then add silicone oil and a solid anti-sticking agent and mix and dissolve them together to prepare a first demoulding liquid for standby use; first dye receiving liquid: dissolve the third resin in a solvent, then add an anti-sticking agent, a curing aid, and a cross-linking agent and mix and dissolve them together to prepare a first dye receiving liquid for standby use; white light-shielding liquid: dissolve the fourth resin in a solvent, then add a dispersant and a pigment and grind them, and after the grinding is completed, add an antioxidant, a light stabilizer, and a fluorescent whitening agent and mix and dissolve them together to prepare a white light-shielding liquid for standby use; bonding liquid: dissolve the fifth resin in a solvent, then add a crystalline polyester resin and a polyurethane resin and mix and dissolve them together to prepare a bonding liquid for standby use; first back coating liquid: dissolve the first resin in a solvent, then add a polyisocyanate curing agent, an inorganic filler, and a demoulding agent and mix and dissolve them together to prepare a first back coating liquid for standby use; S2: applying corona to both sides of the first substrate; S3: Coating: Apply a first back coating liquid to one side of the first substrate subjected to corona discharge, and then dry to form a first back coating layer for standby use; then apply a first release liquid to the side of the first substrate away from the first back coating layer, and then dry to form a first release layer; then apply a first dye receiving liquid to the side of the first release layer away from the first substrate, and then dry to form a first dye receiving layer; apply a white light-shielding liquid to the side of the first dye receiving layer away from the first substrate, and then dry to form a white light-shielding layer; apply a bonding liquid to the side of the white light-shielding layer away from the first substrate, and then dry to form a bonding layer; thus, a first transfer carbon ribbon is obtained; The preparation method of the second transfer carbon ribbon is as follows: S1: preparing a liquid: a second release liquid: dissolving the second resin in a solvent, then adding silicone oil and a solid anti-sticking agent, mixing and dissolving them together to prepare a second release liquid, which is set aside; a second dye receiving liquid: dissolving the third resin in a solvent, then adding an anti-sticking agent, a curing aid, and a cross-linking agent, mixing and dissolving them together to prepare a second dye receiving liquid, which is set aside; a second back coating liquid: dissolving the first resin in a solvent, then adding a polyisocyanate curing agent, an inorganic filler, and a release agent, mixing and dissolving them together to prepare a second back coating liquid, which is set aside; S2: applying corona to both sides of the second substrate; S3: Coating: Coat the second back coating liquid on one of the corona-charged sides of the second substrate, and then dry it to form a second back coating layer for standby use; then coat the second release liquid on the side of the second substrate away from the second back coating layer, and then dry it to form a second release layer; then coat the second dye-receiving liquid on the side of the second release layer away from the second substrate, and then dry it to form a second dye-receiving layer, thereby obtaining a second transfer carbon ribbon.

Images