Post-printing BOPP adhesive tape and preparation method thereof

Abstract

The invention relates to a post-printing BOPP (biaxially-oriented polypropylene) adhesive tape and a preparation method thereof, and solves the problem that ink is easy to fall off in the conventional post-printing adhesive tape. Comprising the following steps: step 1, preparation of a release agent, step 2, coating of the release agent, and step 3, gluing: coating treatment and product structure change are emphasized, in order to guarantee printing feasibility, the compatibility and adhesion firmness of a printing layer and a release layer are solved, that is, ink is printed without falling off, a silicon-free solvent type release agent is selected, and the silicon-free solvent type release agent is used as a raw material; a molecular chain contains a non-polar functional group which has a small acting force on adhesive molecules, and the non-polar functional group can be slightly peeled from a pressure-sensitive adhesive. The release agent with good compatibility with the printing layer is selected, so that the printing ink is well attached to the release layer; a certain amount of emulsion resin is added into the release agent, and the emulsion resin can further enhance the adhesion fastness between the coating and the base material and between the coating and the printing layer. Therefore, the prepared adhesive tape ink is firm in printing, and the effect of printing before ink printing can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, and in particular to a post-printed BOPP tape and a preparation method thereof. Background Art

[0002] BOPP tape is made of biaxially stretched polyethylene film as the base material, and a pressure-sensitive adhesive is applied on one side of the base material to form a roll; it is mainly used for cargo packaging and sealing. The gluing process is the key to the production of BOPP tape, which involves environmental protection treatment. The gluing process can only be completed in factories with certain production conditions. Some sealing tapes have personalized requirements and need to be printed with specific patterns and texts on the tape; the existing production process is to complete the printing before gluing (called pre-printing). This printing method will not lose ink. See the product structure. Figure 1 , production process see Figure 2 , which are the substrate layer 11, the printing layer 12 and the adhesive layer 13. From the product structure, it can be seen that the printing layer and the adhesive layer are on the same side of the substrate, and printing must be done before gluing, which means that printing can only be done at the factory. Since the gluing at the factory is done with large-scale wide-width equipment, batch production (generally more than 10,000 square meters) is required, customers with small batch (10-1,000 square meters) printing needs cannot meet the quantity requirements required by the factory.

[0003] With current technology, if the printing process is simply changed to printing on the non-glue-coated surface of the substrate after gluing (called post-printing), the printing effect will not meet the use requirements, and the ink will easily fall off when the tape is pulled apart during use. Summary of the invention

[0004] The invention aims to solve the problem that the ink of the existing post-printing adhesive tape is easy to fall off.

[0005] The technical solution adopted to solve the technical problem proposed by the present invention is: the preparation method of the post-printed BOPP tape of the present invention comprises the following steps: Step 1: Preparation of release agent: 1.1. According to the ratio and addition order of the release agent materials in the following ratio table, add the materials into the mixing barrel and mix them evenly to obtain the release agent; Step 2: Apply release agent: 2.1. Apply release agent: adopt non-direct coating process, the release agent is first adsorbed on the anilox roller, and then the release agent is transferred and attached to the substrate BOPP film through the lamination of the anilox roller and the film; 2.2. After the release agent is applied, the release layer is cured by evaporating the solvent in a high-temperature oven; 2.3. After curing, the BOPP film is cooled by a cooling roller and rolled up for use; Step 3: Glue application: 3.1. Gluing: Pull the cured BOPP silicone film into the guide roller of the machine. The initial speed of the machine is 20-30 m / min. Pump the prepared glue into the glue tank and apply the glue with a scraper on the glued surface of the film. The amount of glue and uniformity are controlled by adjusting the gap between the scraper and the backing glue roller. The amount of glue is controlled between 18 and 28 g / ㎡ according to product requirements. The machine is not heated during the gluing section. The normal gluing speed of the machine is increased to 90-120 m / min, and the unwinding tension is controlled at 0.8-1.5 kgf. 3.2. Drying and rolling.

[0006] Step 4: Printing after slitting: Slit the tape into appropriate widths as needed and then print on the release layer.

[0007] A post-printed BOPP tape, characterized in that the tape is prepared by the preparation method of the present invention.

[0008] The technical solutions for further limiting the present invention include: In the step 2, the pre-treatment before applying the release agent is to perform corona treatment on the surface of the BOPP film on which the release agent is applied.

[0009] In the step 2, the temperature of the cooling roller is controlled between 22 and 25° C., and the winding tension is controlled between 2 and 5 kgf.

[0010] In the step 2, the BOPP film is pulled into the machine guide roller and transmitted to the corona machine, the machine speed is controlled at 80-110 m / min, and the unwinding tension is controlled at 1.5-3 kgf; the output voltage of the corona machine is adjusted to 2-3.5 KV, and the output current is 10-16 A, and the silicon-coated surface of the BOPP film is subjected to high-frequency and high-voltage electric spark impact to oxidize the film surface molecules to produce polarity.

[0011] In the step 3, the pre-coating treatment is to perform corona treatment on the coated surface of the BOPP silicone film.

[0012] In the step three, the BOPP film coated with glue enters the drying and recovery system, with a total of eight ovens. The temperatures of the first to eighth ovens are controlled at 50±5°C, 60±5°C, 70±5°C, 80±5°C, 95±5°C, 95±5°C, 90±5°C, and 80±5°C respectively. The dryness of the winding tape is controlled between 1% and 2%, and the winding tension is controlled at 20 to 25 Kgf.

[0013] In the step three, the initial speed is 20 m / min, the unwinding tension is 0.9 kgf, and the glue coating amount is 22±1 g / ㎡.

[0014] In the step 1, the substrate is a BOPP film with a thickness of 24 to 60 um.

[0015] Through the above technical scheme, the beneficial effect of the present invention is that the tape ink prepared by the preparation method of the post-printed BOPP tape of the present invention is firmly printed and can achieve the effect of pre-printing of the ink. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a schematic structural diagram of a tape according to the background technology of a method for preparing a post-printed BOPP tape.

[0017] Figure 2 The present invention is a schematic diagram of the production process flow of a post-printed BOPP tape, which is the background technology of the preparation method of the present invention.

[0018] Figure 3 The figure is a schematic structural diagram of a post-printed BOPP tape of the present invention.

[0019] Figure 4 The present invention is a schematic diagram of the production process of a post-printed BOPP tape. DETAILED DESCRIPTION

[0020] The structure of the present invention is further described below in conjunction with the accompanying drawings.

[0021] Reference Figures 1 to 4 A method for preparing a post-printed BOPP tape comprises the following steps: Step 1: Preparation of release agent: 1.1. According to the ratio and addition order of the release agent materials in the following ratio table, add the materials into the mixing barrel in turn and mix them evenly. Operate at room temperature to obtain the release agent.

[0022] In this embodiment, the stirring speed is controlled at 35 rpm, and the stirring time is 35 minutes.

[0023] The present invention uses a silicon-free solvent-type release agent, the molecular chain of which contains a non-polar functional group having a very small force on the adhesive molecule, and plays a role in lightly peeling off the pressure-sensitive adhesive.

[0024] A release agent with good compatibility with the printing layer (ink) is selected to make the ink adhere to the release layer better. In the present invention, a silicon-free solvent-type release agent (non-silicon release agent) is more suitable. The non-silicon release agent is an octadecyl polymer compound, a single component, and contains polar functional groups in the molecular chain that have good adhesion to ink materials and polyolefin materials, and has better adhesion than silicone; Adding a certain amount of emulsion resin to the release agent can further strengthen the adhesion between the coating and the substrate, and between the coating and the printed layer.

[0025] Step 2: Apply release agent: 2.1. Applying release agent: Pre-treatment before applying release agent: In order to increase the adhesion of the release agent on the film surface, the release agent-coated surface of the BOPP film is subjected to corona treatment. The substrate can be a BOPP film with a thickness of 24 to 60 um. The BOPP film is pulled into the machine guide roller and conveyed to the corona machine. The machine speed is controlled at 80 to 110 m / min, and the unwinding tension is controlled at 1.5 to 3 kgf. The output voltage of the corona machine is adjusted to 2 to 3.5 KV, and the output current is 10 to 16 A. The silicon-coated surface of the BOPP film is subjected to high-frequency and high-voltage electric spark impact to oxidize the molecules on the film surface to produce polarity, so as to facilitate better adsorption of the release agent on the film surface. When applying the release agent, a non-direct coating process is adopted. The release agent is first adsorbed on the anilox roller, and then the release agent is transferred and attached to the substrate BOPP film through the bonding of the anilox roller and the film. In this embodiment, 2.2. After the release agent is applied, the release layer is cured by evaporating the solvent in a high-temperature oven; 2.4. After curing, the BOPP film is cooled by a cooling roller and rolled up for standby use; the temperature of the cooling roller is controlled between 22 and 25°C, and the winding tension is controlled between 2 and 5 kgf.

[0026] In this embodiment, a transparent BOPP film with a thickness of 28um and a width of 1280mm is selected. The preferred corona machine output voltage is 2.5KV, the output current is 12A, the machine speed is 85m / min, the unwinding tension is 1.8±0.5Kgf, the release coating amount (wet amount) is 4-4.5g / ㎡, the cooling roller temperature is 23±1℃, and the winding tension is 2.5±0.5Kgf.

[0027] Step 3: Glue application: 3.1. Gluing: Pre-treatment of glue coating: In order to increase the adhesion of glue on the film surface, corona treatment is performed on the glue-coated surface of BOPP silicone film. When coating, the BOPP silicone film with cured coating is pulled into the guide roller of the machine. The initial speed of the machine is 20-30 m / min. The prepared glue is pumped into the glue tank and coated with a scraper. The glue is applied on the glue-coated surface of the film. The amount of glue and uniformity are controlled by adjusting the gap between the scraper and the backing glue roller. The amount of glue is controlled between 18 and 28 g / ㎡ according to product requirements. The machine is not heated during the coating section. The normal gluing speed of the machine is increased to 90-120 m / min, and the unwinding tension is controlled at 0.8-1.5 kgf. 3.2 Drying and winding. The BOPP film coated with glue enters the drying and recycling system, which has eight ovens. The temperature of the first to eighth ovens is controlled at 50±5℃, 60±5℃, 70±5℃, 80±5℃, 95±5℃, 95±5℃, 90±5℃, 80±5℃, respectively. The dryness of the winding tape is controlled between 1% and 2%, and the winding tension is controlled between 20 and 25 Kgf.

[0028] The gluing process of this embodiment is: initial speed 20 m / min, unwinding tension 0.9 Kgf, glue coating amount 22±1 g / ㎡, normal gluing speed 100 m / min, the temperatures of the first to eighth ovens are 50±2°C, 60±2°C, 70±2°C, 80±2°C, 95±2°C, 95±2°C, 90±2°C, 80±2°C respectively, the dryness of the winding tape is 1.3%, and the winding tension is 22 Kgf.

[0029] Step 4: Print after slitting. Slit the tape into appropriate widths as needed and then print on the release layer.

[0030] A post-printed BOPP tape, the tape is prepared by the preparation method of the present invention. Figure 3 , from top to bottom are a printing layer 21 , a release agent layer 22 , a substrate layer 23 and an adhesive layer 24 .

[0031] Comparison test The same ink and the same thickness of substrate were used to produce pre-printed and post-printed BOPP adhesive tapes for comparative testing of ink adhesion performance, as follows The adhesive tape prepared by the preparation method of the post-printed BOPP adhesive tape of the present invention has firm ink printing and can achieve the effect of pre-ink printing.

[0032] Although the specific embodiments of the present invention are described in detail in conjunction with the accompanying drawings, it should not be understood as limiting the scope of protection of the present invention. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still belong to the scope of protection of the present invention.

Claims

1. A method for preparing a post-printed BOPP tape, the method comprising the following steps: Step 1: Preparation of release agent: 1.

1. According to the ratio and addition order of the release agent materials in the following ratio table, add the materials into the mixing barrel and mix them evenly to obtain the release agent; Step 2: Apply release agent: 2.

1. Apply release agent: adopt non-direct coating process, the release agent is first adsorbed on the anilox roller, and then the release agent is transferred and attached to the substrate BOPP film through the lamination of the anilox roller and the film; 2.

2. After the release agent is applied, the solvent is evaporated and separated in a high-temperature oven to complete the curing of the release layer; 2.

3. After curing, the BOPP film is cooled by a cooling roller and rolled up for use; Step 3: Glue application: 3.

1. Gluing: Pull the cured BOPP silicone film into the guide roller of the machine. The initial speed of the machine is 20-30 m / min. Pump the prepared glue into the glue tank and apply the glue with a scraper on the glued surface of the film. The amount of glue and uniformity are controlled by adjusting the gap between the scraper and the backing glue roller. The amount of glue is controlled between 18 and 28 g / ㎡ according to product requirements. The machine is not heated during the gluing section. The normal gluing speed of the machine is increased to 90-120 m / min, and the unwinding tension is controlled at 0.8-1.5 kgf. 3.2, Drying and rolling; Step 4: Printing after slitting: According to the needs, slit the tape into appropriate widths and print on the release layer.

2. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step 2, the pre-treatment before applying the release agent is to perform corona treatment on the surface of the BOPP film on which the release agent is applied.

3. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step 2, the temperature of the cooling roller is controlled between 22 and 25° C., and the winding tension is controlled between 2 and 5 kgf.

4. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step 2, the BOPP film is pulled into the machine guide roller and transmitted to the corona machine, the machine speed is controlled at 80-110 m / min, and the unwinding tension is controlled at 1.5-3 kgf; the output voltage of the corona machine is adjusted to 2-3.5 KV, and the output current is 10-16 A, and the silicon-coated surface of the BOPP film is subjected to high-frequency and high-voltage electric spark impact to oxidize the film surface molecules to produce polarity.

5. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step 3, the pre-coating treatment is to perform corona treatment on the coated surface of the BOPP silicone film.

6. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step three, the BOPP film coated with glue enters the drying and recovery system, with a total of eight ovens. The temperatures of the first to eighth ovens are controlled at 50±5°C, 60±5°C, 70±5°C, 80±5°C, 95±5°C, 95±5°C, 90±5°C, and 80±5°C respectively. The dryness of the winding tape is controlled between 1% and 2%, and the winding tension is controlled at 20 to 25 Kgf.

7. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step three, the initial speed is 20 m / min, the unwinding tension is 0.9 kgf, and the glue coating amount is 22±1 g / ㎡.

8. The method for preparing a post-printed BOPP tape according to claim 1, characterized in that: In the step 1, the substrate is a BOPP film with a thickness of 24 to 60 um.

9. A post-printed BOPP tape, characterized in that: The adhesive tape is prepared by the preparation method described in any one of claims 1-8.

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