Antistatic back coating, thermal transfer ribbon and preparation method thereof

Abstract

The invention relates to an antistatic back coating, a thermal transfer ribbon and a preparation method thereof, and relates to the technical field of thermal transfer ribbons, the antistatic back coating comprises the following components by weight: 10-15 parts of heat resistant resin, 2-4 parts of an adhesive, 0.5-1.5 parts of a metal oxide and 0.5-1.5 parts of conductive carbon black. The metal oxide and the conductive carbon black are added into the back coating, and the conductive substances can form a conductive path on the surface of the thermal transfer ribbon, so that generated static electricity can be conducted and dissipated in time, static electricity accumulation is avoided, static electricity existing during printing is remarkably improved, normal printing quality is ensured, and the service life of a printing head is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of thermal transfer carbon ribbons, and in particular to an antistatic back coating, a thermal transfer carbon ribbon and a preparation method thereof. Background Art

[0002] In thermal transfer technology, a thermal transfer carbon ribbon usually includes a front layer and a back layer. Among them, the thermal transfer front layer achieves high-quality printing effects, and the back coating layer provides appropriate slip and stability. Most thermal transfer carbon ribbons on the market currently have the problem of too high static electricity values ​​when printing. The presence of static electricity will cause the carbon ribbon to adsorb impurities such as dust and paper scraps. These impurities will adhere to the print head or the carbon ribbon, affecting the transfer and adhesion of ink, resulting in quality problems such as white spots, blur or missing on the printed material, and will further increase the friction between the print head and the carbon ribbon, aggravating the wear of the print head, greatly reducing the service life of the print head. In order to solve the above problems, most manufacturers choose to add an appropriate amount of antistatic agent to the back coating layer. However, using an infrared static detector in the actual printing process can find that this method does not effectively reduce the static electricity value. In view of this, the present invention provides an antistatic back coating layer, a thermal transfer carbon ribbon and a preparation method thereof. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an antistatic back coating, a thermal transfer carbon ribbon and a preparation method thereof. The purpose is to provide a back coating with antistatic function, which can significantly improve the static electricity existing during printing, thereby ensuring high-quality printing effects and extending the service life of the print head.

[0004] The technical solution of the present invention to solve the above technical problems is as follows:

[0005] In a first aspect, an antistatic back coating layer comprises the following components in parts by weight:

[0006] 10-15 parts of heat-resistant resin, 2-4 parts of binder, 0.5-1.5 parts of metal oxide and 0.5-1.5 parts of conductive carbon black.

[0007] The beneficial effects of the present invention are as follows: by adding metal oxides and conductive carbon black to the back coating, these conductive substances can form a conductive path on the surface of the carbon ribbon, so that the generated static electricity can be conducted and dissipated in time, thereby avoiding the accumulation of static electricity, significantly improving the static electricity existing during printing, ensuring normal printing quality and extending the service life of the print head.

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

[0009] Further, the heat-resistant resin includes at least one of polyvinyl butyral resin, polyvinyl acetal resin, polyester resin, vinyl chloride-vinyl acetate copolymer polyether resin, polybutadiene resin, styrene-pentadiene copolymer acrylic polyol, polyurethane acrylate, polyester acrylate polyether acrylate, epoxy acrylate, polyurethane epoxy prepolymer, nitrocellulose resin, cellulose acetate propionate resin, cellulose acetate butyrate resin, cellulose acetate butyrate hydrogen diphthalate resin, cellulose acetate resin, aromatic polyamide resin, polyimide resin, polyamideimide resin, polycarbonate resin, chlorinated polyolefin resin, and acrylic modified silicone resin;

[0010] The adhesive includes cellulose acetate, polyvinyl acetal, acrylic resin and isocyanate resin; based on the appropriate bonding properties and considering the heat resistance and stability of the coating, polyisocyanate compounds are further preferred as the adhesive;

[0011] The metal oxide includes at least one of zinc oxide and titanium oxide.

[0012] Furthermore, the antistatic back coating layer further comprises at least one of an auxiliary agent and a filler;

[0013] The auxiliary agent includes at least one of silicone oil, polyethylene wax (PE wax), paraffin, higher fatty acid ester, higher fatty amide, higher fatty alcohol, anionic surfactant, cationic surfactant, nonionic surfactant, organic carboxylic acid, organic carboxylic acid derivative and metal soap;

[0014] The filler includes at least one of spherical silicone resin, silicon dioxide, and melamine formaldehyde resin.

[0015] The beneficial effect of the above further solution is that the additives and fillers of the present invention ensure the smoothness and heat resistance of the print head and the substrate, and avoid the undesirable phenomena such as stickiness or wrinkles caused by heating of the temperature-sensitive heating head during thermal transfer.

[0016] Furthermore, the back coating layer has a thickness of 0.5 μm-1.2 μm, and more preferably 0.2-0.6 μm.

[0017] In a second aspect, a method for preparing an antistatic back coating comprises the following steps:

[0018] Dissolve the components in the antistatic back coating layer in 2-butanone and toluene to obtain a back coating liquid; use a 200-250 line ceramic anilox roller to coat the back coating liquid on the substrate layer through a gravure coater at a coating speed of 60m / min-100m / min, and dry at a temperature of 60℃-100℃ to obtain an antistatic back coating layer on the substrate layer. In the preparation process, corona needs to be applied on both sides of the substrate layer.

[0019] Furthermore, the thickness of the substrate layer is 0.5μm-50μm, and the material of the substrate layer can be one of polyethylene terephthalate (PET) film, 1,4-polycyclohexylene dimethylene terephthalate film, polyethylene naphthalate (PEN) film, polyphenylene sulfide film, polystyrene (PS) film, polypropylene (PP) film, polyethylene (PE) film, polyvinyl chloride film, nylon film, polyimide film, etc., and the preferred thickness is 1-10μm.

[0020] In a third aspect, a thermal transfer carbon ribbon comprises the antistatic back coating.

[0021] Furthermore, it also includes a release layer and an ink layer; the release layer is arranged on a side of the substrate layer away from the back coating layer, and the release layer is arranged on the ink layer;

[0022] The release layer comprises polyester resin A and polyethylene glycol, and the mass ratio of the polyester resin A to the polyethylene glycol is 8-15:2-8;

[0023] The ink layer comprises polyester resin B, pigment and solid particles; the mass ratio of the polyester resin B, the pigment and the solid particles is 8-15:4-8:0.05-2.

[0024] Furthermore, in the release layer, the molecular weight of the polyester resin A is between 3000 and 15000, and the Tg value is between 50° C. and 100° C.; the molecular weight of the polyethylene glycol is between 6000 and 25000;

[0025] In the ink layer, the molecular weight of the polyester resin B is 3000-20000, preferably 5000-15000, the hydroxyl value is >10 mg / g, and the Tg value is 50°C-90°C; the pigment includes an inorganic pigment or an organic pigment, such as carbon black, titanium dioxide, iron oxide, etc.; the solid particles include at least one of silicon dioxide, zinc stearate, and thermosetting acrylic particles.

[0026] Furthermore, the release layer has a thickness of 0.2um-0.6um, preferably 0.3um-0.5um, and the ink layer has a thickness of 0.3um-0.8μm, preferably 0.5um-0.7um.

[0027] In a fourth aspect, a method for preparing a thermal transfer ribbon comprises the following steps: dissolving each component in a release layer in 2-butanone and toluene to obtain a release layer liquid; dissolving each component in an ink layer in 2-butanone and toluene to obtain an ink layer coating liquid;

[0028] A 230-250-line ceramic anilox roller is used to sequentially coat the release layer liquid and the ink layer coating liquid on the side of the substrate layer away from the back coating layer through a gravure coater, with a coating speed of 60m / min-100m / min, and the film is dried at a temperature of 60°C-100°C to obtain a thermal transfer carbon ribbon. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the present invention;

[0030] Figure 2 This is the printing test chart of the present invention.

[0031] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0032] 1-substrate layer, 2-release layer, 3-ink layer, 4-back coating layer. DETAILED DESCRIPTION

[0033] The principles and features of the present invention are described below, and the examples are only used to explain the present invention and are not used to limit the scope of the present invention. If no specific technology or conditions are specified in the embodiments, the technology or conditions described in the literature in this field or the product instructions are used. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased through regular channels.

[0034] Embodiment 1:

[0035] The present embodiment relates to a thermal transfer ribbon, comprising an antistatic back coating 4, a release layer 2 and an ink layer 3; the release layer 2 is arranged on a side of a substrate layer 1 away from the back coating 4, and the release layer 2 is arranged on the ink layer 3 ( Figure 1 );

[0036] The release layer 2 coating liquid: weigh the following raw materials polyethylene glycol (PEG-2000, Jiangsu Haian Petrochemical) 2 parts, polyester resin (CL150, Hanhai New Materials) 8 parts, 2-butanone 45 parts, toluene 45 parts;

[0037] The ink layer 3 coating liquid: weigh the raw material polyester resin (AH651, Hanhai New Materials) 12 parts, carbon black 7 parts, solid particles (silicon dioxide) 1 part, toluene 40 parts, 2-butanone 40 parts according to the following proportions; the back coating layer 4 coating: 2-butanone 40 parts, toluene 40 parts, acrylic modified silicone resin, WSA1070, DIC) 10 parts, polyvinyl butyral resin (B17TX, Changchun Chemical) 3 parts, polyisocyanate 3 parts, silicone resin filler (KMP590, Shin-Etsu) 1 part, leveling agent 1 part, metal oxides and conductive carbon black as shown in Table 1.

[0038] A 200-line ceramic anilox roller was used to coat the back coating layer 4 liquid on the substrate layer 1 through a gravure coater at a coating speed of 70 m / min, and the coating was dried at a temperature of 60°C-100°C to obtain an antistatic back coating layer 4 on the substrate layer 1; a 250-line ceramic anilox roller was used to sequentially coat the release layer 2 liquid and the ink layer 3 coating liquid on the side of the substrate layer 1 away from the back coating layer 4 through a gravure coater at a coating speed of 100 m / min, and the coating was dried at a temperature of 60°C-100°C to obtain a thermal transfer carbon ribbon.

[0039] Embodiments 2 to 8:

[0040] Compared with Example 1, except for the metal oxide and the conductive carbon black, the rest are the same as Example 1.

[0041] Table 1

[0042]

[0043] Comparative Examples 1 to 3:

[0044] Compared with Example 1, conventional antistatic agents are used instead of metal oxides and conductive carbon black, and the rest are the same as Example 1.

[0045] Table 2

[0046] Antistatic Agents Comparative Example 1 Comparative Example 2 Comparative Example 3 DuPont 450 antistatic agent 1 1 0 Heda 129 antistatic agent 1 0 1 Heda 163 antistatic agent 0 1 1

[0047] Test example:

[0048] (1) Print test

[0049] The resin ribbon prepared in this embodiment was placed in a constant temperature box for ring testing using a label printer (manufactured by Zebra, model 105SLPlus) and placed in an environment with temperature / humidity conditions of -20°C / 20%, 60°C / 20%, and 60°C / 90% for 12 hours respectively, and the ring testing lasted for 36 hours. Figure 2 Lines shown (0.6pt thick); print speed set to 12.7cm / s, print density set to 25.

[0050] (2) Electrostatic detection:

[0051] The static electricity value generated during printing was tested using a handheld infrared static detector SIMCO FMX-004. The results are shown in Tables 3 and 4.

[0052] Table 3 Static values ​​of Examples 1 to 8

[0053]

[0054] Table 4 Electrostatic Values ​​of Comparative Examples 1 to 3

[0055] Comparative Example 1 2 3 Static value 0.7kv 0.9kv 0.4kv

[0056] In summary, the present invention adds metal oxides and conductive carbon black to the back coating 4. These conductive substances can form a conductive path on the surface of the carbon ribbon, so that the generated static electricity can be conducted and dissipated in time, thereby avoiding the accumulation of static electricity, significantly improving the static electricity existing during printing, ensuring normal printing quality and extending the service life of the print head.

[0057] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An antistatic back coating, characterized in that: The antistatic back coating layer comprises the following components in parts by weight: 10-15 parts of heat-resistant resin, 2-4 parts of adhesive, 0.5-1.5 parts of metal oxide and 0.5-1.5 parts of conductive carbon black.

2. An antistatic back coating according to claim 1, characterized in that: The heat-resistant resin includes at least one of polyvinyl butyral resin, polyvinyl acetal resin, polyester resin, vinyl chloride-vinyl acetate copolymer polyether resin, polybutadiene resin, styrene-pentadiene copolymer acrylic polyol, polyurethane acrylate, polyester acrylate polyether acrylate, epoxy acrylate, polyurethane epoxy prepolymer, nitrocellulose resin, cellulose acetate propionate resin, cellulose acetate butyrate resin, cellulose acetate butyrate hydrogen diphthalate resin, cellulose acetate resin, aromatic polyamide resin, polyimide resin, polyamideimide resin, polycarbonate resin, chlorinated polyolefin resin, and acrylic modified silicone resin; The adhesive comprises at least one of cellulose acetate, polyvinyl acetal, acrylic resin and isocyanate resin; The metal oxide includes at least one of zinc oxide and titanium oxide.

3. The antistatic back coating according to claim 1, characterized in that: The antistatic back coating layer further comprises at least one of an auxiliary agent and a filler; The auxiliary agent includes at least one of silicone oil, polyethylene wax, paraffin, higher fatty acid ester, higher fatty amide, higher fatty alcohol, anionic surfactant, cationic surfactant, nonionic surfactant, organic carboxylic acid, organic carboxylic acid derivative and metal soap; The filler includes at least one of spherical silicone resin, silicon dioxide, and melamine formaldehyde resin.

4. An antistatic back coating according to claim 3, characterized in that: The back coating layer has a thickness of 0.5 μm-1.2 μm.

5. A method for preparing an antistatic back coating according to claims 1 to 4, characterized in that: The steps include: The components in the antistatic back coating layer are dissolved in 2-butanone and toluene to obtain a back coating liquid; a ceramic anilox roller with 200-250 lines is used to coat the back coating liquid on the substrate layer through a gravure coater at a coating speed of 60m / min-100m / min, and the back coating liquid is dried at a temperature of 60°C-100°C to obtain an antistatic back coating layer on the substrate layer.

6. A thermal transfer ribbon, characterized in that: The invention comprises the antistatic back coating layer according to any one of claims 1 to 5.

7. A thermal transfer ribbon according to claim 6, characterized in that: It also includes a release layer and an ink layer; the release layer is arranged on a side of the substrate layer away from the back coating layer, and the release layer is arranged on the ink layer; The release layer comprises polyester resin A and polyethylene glycol, and the mass ratio of the polyester resin A to the polyethylene glycol is 8-15:2-8; The ink layer comprises polyester resin B, pigment and solid particles; the mass ratio of the polyester resin B, the pigment and the solid particles is 8-15:4-8:0.05-2.

8. A thermal transfer ribbon according to claim 7, characterized in that: In the release layer, the molecular weight of the polyester resin A is between 3000 and 15000, and the Tg value is between 50° C. and 100° C.; the molecular weight of the polyethylene glycol is between 6000 and 25000; In the ink layer, the molecular weight of the polyester resin B is 3000-20000, the hydroxyl value is >10 mg / g, and the Tg value is 50°C-90°C; the pigment includes an inorganic pigment or an organic pigment; and the solid particles include at least one of silicon dioxide, zinc stearate, and thermosetting acrylic particles.

9. A thermal transfer ribbon according to claim 7, characterized in that: The thickness of the release layer is 0.2um-0.6um, and the thickness of the ink layer is 0.3um-0.8μm.

10. A method for preparing a thermal transfer carbon ribbon according to any one of claims 6 to 9, characterized in that: The method comprises the following steps: dissolving each component in the release layer in 2-butanone and toluene to obtain a release layer liquid; dissolving each component in the ink layer in 2-butanone and toluene to obtain an ink layer coating liquid; A 230-250-line ceramic anilox roller is used to sequentially coat the release layer liquid and the ink layer coating liquid on the side of the substrate layer away from the back coating layer through a gravure coater, with a coating speed of 60m / min-100m / min, and the film is dried at a temperature of 60°C-100°C to obtain a thermal transfer carbon ribbon.

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