PET electronic tag printing film and preparation method thereof

Abstract

The invention relates to the technical field of printing films, in particular to a PET electronic tag printing film and a preparation method thereof.The preparation method comprises the following steps that S1, heat-resistant low-shrinkage functional master batch A is prepared, specifically, organic-inorganic hybrid functional powder P1 with an epoxy functional group is synthesized firstly, then the functional powder P1 and polyester chips are evenly mixed and extruded through a screw extruder, and the heat-resistant low-shrinkage functional master batch A is obtained; granulating to obtain a heat-resistant low-shrinkage functional master batch A; s2, preparation of the PET electronic tag film: mixing the functional master batch A, the opening master batch B and the polyester chips, and preparing the heat-resistant low-shrinkage PET electronic tag film by using a two-way stretching process; s3, preparing a water-based functional pre-coating layer; and S4, preparation of the PET electronic tag printing film: diluting the prepared water-based functional pre-coating glue, coating the water-based functional pre-coating glue on the PET electronic tag film prepared in the step S2, and drying to obtain the PET electronic tag printing film. According to the preparation method disclosed by the invention, the PET is modified by adopting a nano silicon dioxide in-situ copolymerized acrylic resin material with an epoxy functional group to improve the heat resistance and the heat shrinkage rate at high temperature.

Description

Technical Field

[0001] The invention relates to the technical field of printing films, in particular to a PET electronic label printing film and a preparation method thereof. Background Art

[0002] PET film has good heat resistance and insulation, and is increasingly used in electronic labels. The current electronic label film has a longitudinal shrinkage rate of ≥0.1% at 180℃ / 30min, resulting in poor processability and poor dimensional stability. It is necessary to further improve the heat resistance and longitudinal shrinkage rate of existing polyester films. The digital printing industry has developed rapidly in the past 20 years. Many products have been transferred from traditional printing methods to digital printing methods, and the entire market has continued to increase. The advantage of digital printing is that it can be flexibly typeset and used as needed, which greatly improves efficiency, especially HP Indigo printing and carbon ribbon printing. With the increase in personalized needs in today's society, digital printing methods fully meet the needs of development. At this stage, the printing materials required for digital printing are uneven, and can only adapt to a single printing method. The scope of use is not wide and has great limitations. Specifically, some materials are not heat-resistant enough, resulting in deformation during the fixing process, the machine is not suitable for toner printing, and some materials are not compatible with the printing layer, and can only adapt to a single printing method. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a PET electronic label printing film and a preparation method thereof.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0005] A method for preparing a PET electronic label printing film, the preparation method comprising the following steps:

[0006] Preparation of S1 heat-resistant low-shrinkage functional masterbatch A: First, synthesize the organic-inorganic hybrid functional powder P1 with epoxy functional group, then mix the functional powder P1 and polyester chips through a screw extruder and extrude them uniformly, and granulate them to obtain the heat-resistant low-shrinkage functional masterbatch A;

[0007] S2 Preparation of PET electronic label film: The functional masterbatch A, the open masterbatch B and the polyester chips prepared in step S1 are mixed, and a heat-resistant and low-shrinkage PET electronic label film is obtained by a biaxial stretching process, drying, extruding, stretching, heat-setting, cooling and rolling;

[0008] S3 Preparation of water-based functional pre-coating;

[0009] S4 Preparation of PET electronic label printing film: dilute the water-based functional pre-coating glue prepared in step S3 and apply it on the PET electronic label film prepared in step S2, and dry it to obtain the PET electronic label printing film.

[0010] By adding heat-resistant and low-shrinkage functional masterbatch, the crystallization rate of PET can be changed, which acts as a nucleating agent during the stretching and shaping process, changing the elasticity and plastic deformation of the matrix, thereby improving the heat resistance and heat shrinkage rate of PET. The resin part with epoxy functional group can eliminate the terminal carboxyl group of PET and improve the hydrolysis resistance of PET.

[0011] By coating the surface of the film with a functional pre-coating, the water-based pre-coating contains water-based EAA, and hot-melt bonding with the upper ink is achieved, so that the printing film can be compatible with electronic ink, laser toner, and carbon ribbon printing, eliminating the inconvenience of use.

[0012] Furthermore, the functional powder P1 is an in-situ copolymer of nano-silica and propylene resin powder with epoxy functional groups. The functional powder in step S1 is prepared by in-situ emulsion polymerization of aqueous nano-silica sol and acrylic emulsion containing epoxy functional groups, and the inorganic nano-silica sol is partially connected by chemical bonds formed by acrylic silicone with double bonds and acrylic resin.

[0013] The present invention uses nano-silicon dioxide in-situ copolymerization of propylene resin material with epoxy functional groups to modify PET to improve heat resistance and heat shrinkage rate at high temperature. The addition of nano-silicon dioxide in-situ copolymerization of propylene resin powder with epoxy functional groups changes the crystallization rate of PET and plays a role of nucleating agent in the stretching and shaping process. The surface polarity of nano-silicon dioxide is large and can strongly adsorb PET macromolecular chains, playing the role of physical cross-linking points, thereby limiting the thermal movement of the macromolecular chains and changing the elasticity and plastic deformation of the matrix. The acrylic resin part with epoxy functional groups eliminates the terminal carboxyl group of PET and improves the hydrolysis resistance of PET.

[0014] Furthermore, the amount of nano-silicon dioxide added to the functional powder P1 is 1-3 wt %, and 5 wt % of glycidyl methacrylate (GMA) monomer is introduced into the acrylic resin.

[0015] 5 wt% of glycidyl methacrylate (GMA) monomer is introduced into the acrylic resin. The epoxy functional group can eliminate the terminal carboxyl group in the subsequent PET polyester chips, and reduce the degradation of PET during processing to form small molecules that affect heat resistance.

[0016] Furthermore, in the step S1, the amount of the functional powder P1 added is 5-10wt%, and the amount of the polyester chips added is 90-95wt%.

[0017] Furthermore, in step S2, the added amount of the functional masterbatch A is 10-30wt%, the added amount of the open masterbatch B is 5wt%, and the added amount of the polyester chips is 65-85wt%.

[0018] Furthermore, the percentage composition of the water-based functional pre-coating layer is as follows:

[0019]

[0020] The sum of all the above components equals 100%.

[0021] Since the drying time of thin film coating is very short, the water-based functional pre-coating glue should be designed to be able to dry and roll up quickly. When coating, the water-based glue is required to be bubble-free or low-foam and have good viscosity stability. The re-solubility of the water-based glue is also very important, otherwise it is easy to produce gel particles and coating defects during continuous production. In the present invention, high-temperature cross-linked water-based polymer resin is used to greatly improve the strength and anti-adhesion properties of the film. Precision micro-concave coating can accurately control the thickness of the glue layer to avoid inconsistent performance and rainbow patterns caused by uneven thickness of the glue layer.

[0022] Furthermore, the preparation method of the aqueous pre-functional pre-coating layer comprises the following steps:

[0023] First add water-based polymer resin and water-based EAA, then add water-based antistatic agent, water-based substrate wetting agent, filter to remove foreign particles and foam; before coating, add 2-5% water-based crosslinking agent with a mass fraction of polymer resin, and dilute 1wt% PMMA particles MX-180TA with water to a coating viscosity of 11±1s (coat 4 cups) to obtain a water-based functional pre-coating glue.

[0024] Furthermore, the aqueous crosslinking agent is a carbodiimide crosslinking agent.

[0025] Furthermore, the solid content of the diluted water-based functional pre-coating glue in step S4 is 10wt%, the thickness of the PET electronic label film is 125μm, the dry film thickness of the water-based functional pre-coating is 1-2μm, and the particle size of the PMMA particles is 1-2μm.

[0026] The EAA polymer and other types of water-based polymer resins used in the present invention have a solid content of 10wt%, dry quickly, and have good adhesion to PET. In order to prevent adhesion during the coating and drying process, 0.5wt% of PMMA spherical particles with a particle size of 1-2μm are added to improve the opening and prevent back adhesion.

[0027] The PET electronic label printing film is prepared by the above preparation method.

[0028] The beneficial effects of the technical solution of the present invention are:

[0029] The present invention uses nano-silicon dioxide in-situ copolymerization of propylene resin material with epoxy functional groups to modify PET to improve heat resistance and heat shrinkage rate at high temperature. The addition of nano-silicon dioxide in-situ copolymerization of propylene resin powder with epoxy functional groups changes the crystallization rate of PET and plays a role of nucleating agent in the stretching and shaping process. The surface polarity of nano-silicon dioxide is large and can strongly adsorb PET macromolecular chains, playing the role of physical cross-linking points, thereby limiting the thermal movement of the macromolecular chains and changing the elasticity and plastic deformation of the matrix. The acrylic resin part with epoxy functional groups eliminates the terminal carboxyl group of PET and improves the hydrolysis resistance of PET.

[0030] By coating the surface of the film with a functional pre-coating, the water-based pre-coating contains water-based EAA, and hot-melt bonding with the upper ink is achieved, so that the printing film can be compatible with electronic ink, laser toner, and carbon ribbon printing, eliminating the inconvenience of use.

[0031] The contradiction between hot bonding and anti-adhesion after winding is solved by adding spherical particles with a particle size of 2μm. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with specific implementation methods and description.

[0033] 1. Preparation of heat-resistant and low-shrinkage functional masterbatch A:

[0034] Comparative Example 1

[0035] Preparation of electronic label polyester film:

[0036] 10 wt% of the open masterbatch B and 90 wt% of the common polyester chips WK-711 were mixed, and the PET electronic label film KP1 was obtained by a biaxial stretching process, drying at 150° C., extruding, stretching, heat setting at 240° C., cooling, and winding.

[0037] Example 1

[0038] 5 wt% of organic-inorganic hybrid functional powder P1 with epoxy functional group and 95 wt% of common polyester chips WK-711 were mixed evenly by a screw extruder, extruded, and granulated to obtain functional masterbatch A.

[0039] Among them, the functional powder P1 is nano-silica in-situ copolymerized with propylene resin powder with epoxy functional groups, which is prepared by in-situ emulsion polymerization of water-based nano-silica sol and acrylic emulsion containing epoxy functional groups, and the inorganic nano-silica sol part is chemically bonded to the acrylic resin through acrylic silicone with double bonds. 5wt% of glycidyl methacrylate GMA monomer is introduced into the acrylic resin part.

[0040] Preparation of electronic label polyester film:

[0041] 10 wt% of functional masterbatch A, 5% of open masterbatch B, and 85% of common polyester chips WK-711 were mixed, and the PET electronic label film KP2 was obtained by a biaxial stretching process, drying at 150° C., extruding, stretching, heat setting at 240° C., cooling, and winding.

[0042] Example 2

[0043] 10 wt% of organic-inorganic hybrid functional powder P1 with epoxy functional group and 90 wt% of common polyester chips WK-711 were mixed evenly by a screw extruder, extruded and granulated to obtain functional masterbatch A.

[0044] Preparation of electronic label polyester film:

[0045] 20wt% of functional masterbatch A, 5wt% of open masterbatch B, and 75wt% of common polyester chips WK-711 were mixed, and the PET electronic label film KP3 was obtained by a biaxial stretching process, drying at 150°C, extruding, stretching, heat setting at 240°C, cooling, and winding.

[0046] Example 3

[0047] 10 wt% of organic-inorganic hybrid functional powder P1 with epoxy functional group and 90 wt% of common polyester chips WK-711 were mixed evenly by a screw extruder, extruded and granulated to obtain functional masterbatch A.

[0048] Preparation of electronic label polyester film:

[0049] 30wt% of functional masterbatch A, 5wt% of open masterbatch B, and 65wt% of common polyester chips WK-711 were mixed, and the PET electronic label film KP4 was obtained by a biaxial stretching process, drying at 150°C, extruding, stretching, heat setting at 240°C, cooling, and winding.

[0050] The performance parameters of the PET electronic label films prepared in Examples 1 to 3 are shown in Table 1

[0051]

[0052] Table 1

[0053] From the data in Table 1, it can be seen that with the increase in the amount of functional powder P1, the longitudinal shrinkage at 180°C gradually decreases. However, the haze increases and the film surface appearance deteriorates. The performance tends to be optimal when the addition amount of functional powder P1 is 2%.

[0054] 2. Preparation of PET electronic label printing film

[0055] Example 1

[0056]

[0057] The sum of all the above components equals 100%

[0058] Process:

[0059] First add water-based polymer resin and water-based EAA, then add water-based antistatic agent, substrate wetting agent, filter to remove impurity particles and foam. Before coating, add 2-5% water-based crosslinking agent carbodiimide with a mass fraction of water-based polymer resin, and dilute 1wt% PMMA particles MX-180TA with water to a coating viscosity of 10 (coating 4 cups), and then obtain water-based functional pre-coating glue.

[0060] Drying process:

[0061] The prepared water-based functional pre-coating glue was diluted with water to 10% solid content, and coated on a 125μm corona-treated PET film with a 10μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0062] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0063]

[0064]

[0065] Example 2

[0066]

[0067] The sum of all the above components equals 100%

[0068] Process:

[0069] First add water-based polyurethane resin R-600, water-based EAA, and then add water-based substrate wetting agent, filter to remove impurity particles and foam. Before coating, add 2-5% water-based crosslinking agent carbodiimide with a mass fraction of water-based polymer resin, and dilute 1wt% PMMA particles MX-180TA with water to the coating viscosity of 10 seconds (coat 4 cups), and you will get water-based functional pre-coating glue.

[0070] Drying process:

[0071] The prepared water-based functional pre-coating glue was diluted with water to a solid content of 10 wt%, and coated on a 125 μm corona-treated PET film with a 10 μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0072] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0073]

[0074]

[0075] Example 3

[0076]

[0077] The sum of all the above components equals 100%

[0078] Process:

[0079] First add water-based polyester modified acrylic resin 7005, water-based EAA, then add water-based antistatic agent substrate wetting agent, filter to remove impurity particles and foam. Before coating, add 2-5% water-based crosslinking agent with a mass fraction of water-based polymer resin, and dilute 1wt% PMMA particle MX-180TA with water to a coating viscosity of 11 seconds (coating 4 cups), and you will get a water-based functional pre-coating glue.

[0080] Drying process:

[0081] The prepared water-based functional pre-coating glue was diluted with water to a solid content of 10 wt%, and coated on a 125 μm corona-treated PET film with a 10 μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0082] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0083]

[0084]

[0085] Example 4

[0086]

[0087] The sum of all the above components equals 100%

[0088] Process:

[0089] First add water-based acrylic resin NeoCrylA 1127 and other types of water-based polymer resins, then add water-based antistatic agent, water-based substrate wetting agent, filter to remove foreign particles and foam. Before coating, add 2-5% water-based crosslinking agent with a mass fraction of water-based polymer resin, and dilute 1wt% PMMA particles MX-180TA with water to a coating viscosity of about 11 seconds (coating 4 cups), and then obtain water-based functional pre-coating glue.

[0090] Drying process:

[0091] The prepared water-based functional pre-coating glue was diluted with water to a solid content of 10 wt%, and coated on a 125 μm corona-treated PET film with a 10 μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0092] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0093]

[0094] Example 5

[0095]

[0096] The sum of all the above components equals 100%

[0097] Process:

[0098] First add water-based polycarbonate polyurethane and water-based EAA, then add water-based antistatic agent, water-based substrate wetting agent, filter to remove impurity particles and foam. Before coating, add 2-5% water-based crosslinking agent with a mass fraction of water-based polymer resin, and dilute 1wt% PMMA particles MX-180TA with water to a coating viscosity of 11 seconds (coating 4 cups), and then obtain water-based functional pre-coating glue.

[0099] Drying process:

[0100] The prepared water-based functional pre-coating glue was diluted with water to 2% solid content, and coated on a 125μm corona-treated PET film with a 10μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0101] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0102]

[0103] Example 6

[0104] Water-based EAA 94.5

[0105] Water-based antistatic agent HDC-359 5

[0106] Water-based substrate wetting agent WET 270 0.5

[0107] The sum of all the above components equals 100%

[0108] Process:

[0109] First add water-based EAA resin, then add water-based antistatic agent, water-based substrate wetting agent, filter to remove impurity particles and foam. Before coating, add 2-5% water-based crosslinking agent with water-based polymer resin mass fraction, 1wt% PMMA particle MX-180TA is diluted with water to the coating viscosity of 11 seconds (coating 4 cups), and then obtain water-based functional pre-coating glue.

[0110] Drying process:

[0111] The prepared water-based functional pre-coating glue was diluted with water to a solid content of 10 wt%, and coated on a 125 μm corona-treated PET film with a 10 μ wire rod, placed in an oven at 170°C for 60 seconds, and then cooled to room temperature for performance testing.

[0112] The results of the performance test of the PET pre-coated film prepared in the above example are as follows:

[0113]

[0114] From the test results of the above examples, it can be seen that under the condition of fixed resin and EAA ratio, the polyurethane system has a relatively wider adhesion of the subsequent ink. EAA has a significant effect on improving the adhesion with INDIGO ink. However, too much ratio will reduce the adhesion with PET. Polycarbonate polyurethane with too high softening point is also not conducive to the adhesion of the subsequent ink.

[0115] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary experimental examples, and that the present invention can be implemented in other specific forms without departing from the spirit and essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0116] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent claim scheme. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for preparing a PET electronic label printing film, characterized in that: The preparation method comprises the following steps: S1 Preparation of heat-resistant low-shrinkage functional masterbatch A: First, synthesize the organic-inorganic hybrid functional powder P1 with epoxy functional group, then mix the functional powder P1 and polyester chips through a screw extruder and extrude them uniformly, and granulate them to obtain the heat-resistant low-shrinkage functional masterbatch A; S2 Preparation of PET electronic label film: The functional masterbatch A, the open masterbatch B and the polyester chips prepared in step S1 are mixed, and a heat-resistant and low-shrinkage PET electronic label film is obtained by a biaxial stretching process, drying, extruding, stretching, heat-setting, cooling and rolling; S3 Preparation of water-based functional pre-coating; S4 Preparation of PET electronic label printing film: dilute the water-based functional pre-coating glue prepared in step S3 and apply it on the PET electronic label film prepared in step S2, and dry it to obtain the PET electronic label printing film.

2. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: The functional powder P1 is an propylene resin powder with epoxy functional groups obtained by in-situ copolymerization of nano-silicon dioxide; The functional powder in step S1 is prepared by in-situ emulsion polymerization of aqueous nano-silica sol and acrylic emulsion containing epoxy functional groups, and the inorganic nano-silica sol is partially connected by chemical bonds formed by acrylic silicone with double bonds and acrylic resin.

3. The method for preparing a PET electronic label printing film according to claim 2, characterized in that: The amount of nano-silicon dioxide added in the functional powder P1 is 1-3wt%, and 5wt% of glycidyl methacrylate GMA monomer is introduced into the acrylic resin part.

4. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: In the step S1, the amount of the functional powder P1 added is 5-10wt%, and the amount of the polyester chips added is 90-95wt%.

5. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: In the step S2, the added amount of the functional masterbatch A is 10-30wt%, the added amount of the open masterbatch B is 5wt%, and the added amount of the polyester chips is 65-85wt%.

6. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: The percentage composition of the water-based functional pre-coating is as follows: Waterborne polymer resin 50~65, Water-based EAA 30~35, Water-based antistatic agent 5 ~10, Water-based substrate wetting agent 0.1~0.5, The sum of all the above components equals 100%.

7. The method for preparing a PET electronic label printing film according to claim 6, characterized in that: The method for preparing the aqueous pre-functional pre-coating layer comprises the following steps: First add water-based polymer resin and water-based EAA, then add water-based antistatic agent and water-based substrate wetting agent, filter to remove foreign particles and foam; before coating, add 2-5% water-based crosslinking agent with a mass fraction of polymer resin, and dilute 1wt% PMMA particle MX-180TA with water to a coating viscosity of 11±1s (coat 4 cups) to obtain water-based functional pre-coating glue.

8. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: The aqueous crosslinking agent is a carbodiimide crosslinking agent.

9. The method for preparing a PET electronic label printing film according to claim 1, characterized in that: The solid content of the diluted water-based functional pre-coating glue in step S4 is 10wt%, the thickness of the PET electronic label film is 125μm, the dry film thickness of the water-based functional pre-coating is 1-2μm, and the particle size of the PMMA particles is 1-2μm.

10. A PET electronic label printing film prepared by the preparation method according to any one of claims 1 to 9.

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