阅读说明：本技术 一种用于彩色打印ttr双向拉伸聚酯基膜及其制备方法 (TTR (thermal transfer ribbon) biaxially oriented polyester base film for color printing and preparation method thereof ) 是由 胡爱华 于 2019-10-09 设计创作，主要内容包括：本发明公开了一种用于彩色打印TTR双向拉伸聚酯基膜,由上表层、芯层及下表层构成,所述芯层为PET聚酯切片；所述上表层和下表层的原料按重量份均由40-80份PET聚酯母料和20-60份PET聚酯切片组成；所述PET聚酯母料为含有0.45-0.55wt％二氧化硅的PET聚酯切片。本发明还公开了上述用于彩色打印TTR双向拉伸聚酯基膜的制备方法。本发明打印图案清晰、色彩还原度高,风景和人物图像效果优良,充分满足了目前彩色打印需求。(The invention discloses a TTR (thermal transfer ribbon) biaxially oriented polyester base film for color printing, which consists of an upper surface layer, a core layer and a lower surface layer, wherein the core layer is a PET (polyethylene terephthalate) polyester slice; the raw materials of the upper surface layer and the lower surface layer consist of 40-80 parts of PET polyester master batch and 20-60 parts of PET polyester chips in parts by weight; the PET polyester master batch is PET polyester chips containing 0.45-0.55 wt% of silicon dioxide. The invention also discloses a preparation method of the TTR biaxially oriented polyester base film for color printing. The invention has clear printing pattern, high color reduction degree and excellent landscape and figure image effect, and fully meets the current color printing requirement.)

1. A TTR biaxial stretching polyester basal lamina used for color printing is composed of an upper surface layer, a core layer and a lower surface layer, and is characterized in that the core layer is a PET polyester slice; the raw materials of the upper surface layer and the lower surface layer consist of 40-80 parts of PET polyester master batch and 20-60 parts of PET polyester chips in parts by weight; the PET polyester master batch is PET polyester chips containing 0.45-0.55 wt% of silicon dioxide.

2. TTR biaxially oriented polyester based film for color printing according to claim 1, wherein the particle size of silica is 0.8-1.5 μm; preferably, in the PET polyester chip, the iron is less than or equal to 2mg/kg, the powder is less than or equal to 100mg/kg, and more than 10u of agglutinated particles are less than or equal to 0.8 per mg; preferably, in the PET polyester master batch, the iron is less than or equal to 2mg/kg, the powder is less than or equal to 100mg/kg, and more than 10u of agglutinated particles are less than or equal to 0.8 per mg; preferably, the thickness of the TTR biaxially oriented polyester base film for color printing is 4.4 to 4.6 μm.

3. A method for preparing TTR biaxially oriented polyester film for color printing according to claim 1 or 2, comprising the steps of:

s1, drying the core layer by using PET (polyethylene terephthalate) chips, heating for melting, and filtering to obtain a core layer melt;

s2, uniformly mixing the raw materials of the upper surface layer and the lower surface layer according to the parts by weight, heating for melting, vacuumizing, and filtering to respectively obtain an upper surface layer melt and a lower surface layer melt; converging and extruding the core layer melt, the upper surface layer melt and the lower surface layer melt in a three-layer die head to prepare a mixed melt; the mixed melt is subjected to cold roll and electrostatic attachment to obtain a cast sheet;

and S3, longitudinally stretching the cast sheet to obtain a thick sheet, transversely stretching, performing heat setting to obtain a film, and performing traction rolling to remove floating dust and impurities on the surface of the film in a traction rolling link to obtain the TTR biaxially oriented polyester base film for color printing.

4. The method of claim 3, wherein the preheating temperature for longitudinal stretching is 45-98 ℃, the stretching temperature is 101-103 ℃, and the stretching ratio is 4.3-4.5 times in S3.

5. The method of claim 3 or 4 for preparing TTR biaxially oriented polyester film for color printing, wherein in S3, the preheating temperature for transverse stretching is 90-98 ℃, the stretching temperature is 99-105 ℃, and the stretching ratio is 3.8-4.1.

6. The method for preparing TTR biaxially oriented polyester film for color printing as claimed in any of claims 3-5, wherein the heat setting temperature is 232-238 ℃ in S3.

7. A method of preparing TTR biaxially oriented polyester based film according to any of claims 3 to 6 wherein in S1, S2 the filtration pore size is 5 to 10 μm.

8. The method of any one of claims 3-7 for making TTR biaxially oriented polyester film for color printing, wherein in S3, platinum is added as a catalyst during heat setting.

9. The method for preparing TTR biaxially oriented polyester film for color printing as claimed in any one of claims 3 to 8, wherein the drying temperature is 140 ℃ and 160 ℃ and the drying time is 8 to 10 hours in S1.

10. The method for preparing TTR biaxially oriented polyester base film for color printing as claimed in any one of claims 3 to 9, wherein the extrusion temperature is 275-285 ℃ in S2; preferably, in S3, in the pulling and rolling step, after removing floating dust and impurities on the surface of the film, cooling to room temperature, flattening, performing thickness measurement and rolling, then performing aging treatment for 8 hours at 22-28 ℃ in an environment with humidity of 50-60%, and slitting to obtain the TTR biaxially oriented polyester base film for color printing.

Technical Field

The invention relates to the technical field of polyester base films, in particular to a TTR (transparent temperature-dependent) biaxially oriented polyester base film for color printing and a preparation method thereof.

Background

The film used for TTR printing is a special carbon tape that prints bar codes and text information on labels. With the further pursuit of the market for the printing effect, the demand of printing the color pattern on the label is more and more, and the common TTR carbon ribbon can only print simple bar codes and character information on the label, and cannot meet the demand for color. The TTR film for color printing is based on the principle that three primary colors of 'red, yellow and blue' are coated on a special TTR base film, and the effect of color printing of landscape and portrait patterns is achieved through special printing equipment. In order to ensure that the color pattern is real and fine and put high requirements on the surface structure and cleanliness of the TTR base film, the common TTR biaxially-oriented polyester base filmThe surface roughness Ra is 0.09-0.12 μm, the film surface has no obvious defect and foreign matter, the color printing TTR base film requires the surface roughness Ra less than 0.08 μm, and the film surface cleanliness requires the defect and foreign matter less than or equal to 10/m²Ordinary TTR films are difficult to meet requirements.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides a TTR (transparent transfer ribbon) biaxially oriented polyester base film for color printing and a preparation method thereof.

The invention provides a TTR (thermal transfer ribbon) biaxially oriented polyester base film for color printing, which consists of an upper surface layer, a core layer and a lower surface layer, wherein the core layer is a PET (polyethylene terephthalate) polyester slice; the raw materials of the upper surface layer and the lower surface layer consist of 40-80 parts of PET polyester master batch and 20-60 parts of PET polyester chips in parts by weight; the PET polyester master batch is PET polyester chips containing 0.45-0.55 wt% of silicon dioxide.

Preferably, the particle size of the silica is 0.8-1.5 μm.

Preferably, the particle size of the silica is 1.2 μm.

Preferably, in the PET polyester chip, the iron is less than or equal to 2mg/kg, the powder is less than or equal to 100mg/kg, and more than 10u of agglutinated particles are less than or equal to 0.8 per mg.

Preferably, in the PET polyester master batch, the iron is less than or equal to 2mg/kg, the powder is less than or equal to 100mg/kg, and more than 10u of agglutinated particles are less than or equal to 0.8 per mg.

Preferably, the thickness of the TTR biaxially oriented polyester base film for color printing is 4.4 to 4.6 μm.

The invention also provides a preparation method of the TTR biaxially oriented polyester base film for color printing, which comprises the following steps:

s1, drying the core layer by using PET (polyethylene terephthalate) chips, heating for melting, and filtering to obtain a core layer melt;

s2, uniformly mixing the raw materials of the upper surface layer and the lower surface layer according to the parts by weight, heating for melting, vacuumizing, and filtering to respectively obtain an upper surface layer melt and a lower surface layer melt; converging and extruding the core layer melt, the upper surface layer melt and the lower surface layer melt in a three-layer die head to prepare a mixed melt; the mixed melt is subjected to cold roll and electrostatic attachment to obtain a cast sheet;

and S3, longitudinally stretching the cast sheet to obtain a thick sheet, transversely stretching, performing heat setting to obtain a film, and performing traction rolling to remove floating dust and impurities on the surface of the film in a traction rolling link to obtain the TTR biaxially oriented polyester base film for color printing.

Preferably, in S3, the preheating temperature for longitudinal stretching is 45-98 ℃, the stretching temperature is 101-103 ℃, and the stretching ratio is 4.3-4.5 times.

Preferably, in S3, the preheating temperature for transverse stretching is 90 to 98 ℃, the stretching temperature is 99 to 105 ℃, and the stretching ratio is 3.8 to 4.1 times.

Preferably, in S3, the heat-setting temperature is 232-238 ℃.

Preferably, in S1, S2, the filtration pore size is 5-10 μm.

Preferably, in S3, platinum is added as a catalyst during heat setting.

Preferably, in S1, the drying temperature is 140-160 ℃, and the drying time is 8-10 h.

Preferably, in S2, the extrusion temperature is 275-285 ℃.

Preferably, in S3, in the pulling and rolling step, after removing floating dust and impurities on the surface of the film, cooling to room temperature, flattening, performing thickness measurement and rolling, then performing aging treatment for 8 hours at 22-28 ℃ in an environment with humidity of 50-60%, and slitting to obtain the TTR biaxially oriented polyester base film for color printing.

The invention optimizes and improves the film formula and the production process, the PET polyester master batch is PET polyester slices containing a proper amount of silicon dioxide, and the particle size of the silicon dioxide is smaller; the PET polyester chip and the PET polyester master batch have the characteristics of cleanness and less impurities, so that the cleanliness of the polyester base film can be improved, and the surface structure of the polyester base film can be improved; in the production process, the aperture of melt filtration is 5-10 μm, impurities in the melt are filtered, and dust removal equipment is used in a traction winding link to remove floating dust and impurities on the surface of the film, so that the cleanliness of the polyester base film is further improved; and the prepared TTR biaxially oriented polyester film for color printing has the advantages of excellent physical and mechanical properties, low surface roughness, clean film surface and good ink adhesion by matching with proper processes such as extrusion, stretching, heat setting and the like, and the prepared color TTR printing carbon ribbon has clear and vivid printed patterns and fully meets the current color printing requirements.

Detailed Description

The technical solution of the present invention will be described in detail below with reference to specific examples.