CN115742374A - Polyester antistatic release film and production method thereof - Google Patents

Abstract

The invention discloses a polyester antistatic release film and a production method thereof, belonging to the technical field of antistatic release films.

Description

A kind of polyester antistatic release film and production method thereof

technical field

The invention belongs to the technical field of antistatic release film, and in particular relates to a polyester antistatic release film and a production method thereof.

Background technique

PET release film is a material commonly used in thermal transfer printing. The substrate is PET, which is coated with silicone oil, so it is also called silicone oil film. PET release film has been widely used in packaging, printing, screen printing, pad printing, nameplate, membrane switch, flexible circuit, insulation products, circuit board, laser anti-counterfeiting, lamination, electronics, sealing material film, reflective material, waterproof Materials, medicine, sanitary paper, adhesive products, die-cutting and other industries. There is a sound when peeling off, one is that the release force is too large, and the other is the result of uneven coating. It cannot be peeled off after being pasted with the tape, which is generally the reason for uneven coating. Some release films have serious leakage, which will make a certain part have no release effect, resulting in the tape being unable to peel off. The greasy release surface is mainly caused by the release agent system. It is not that greasy things are necessarily bad. In fact, the surface coating of some greasy release films is relatively uniform, and the residual adhesion rate is better. But some simply have poor adhesion, and the silicone oil is easy to fall off. The release film will generate static electricity during the unwinding and winding process and absorb dust. Condensed silicone release agent was first industrialized in 1954. The addition-type silicone release agent was first industrialized in 1975, mainly through the hydrosilylation reaction of dimethyl polysiloxane with vinyl groups with a cross-linking agent containing silicon-hydrogen bonds under the catalysis of metal platinum compounds. And cross-linked solidification. The curing method of fluorine release agent is thermal curing. Oven length is long. All the fluorine release agents currently on the market are low viscosity and poor leveling. Fluorine release agent needs to add a large amount of solvent to assist leveling. Problems such as rainbow lines and crystal points are all improved and adjusted with solvents. In addition, the tank life of the release agent and the curing efficiency of the film can also be properly adjusted through the solvent. Some fluorine-based release agents on the market must be diluted with fluorine-containing solvents. A single solvent is not acceptable and must be a mixed solvent. Use a strong solvent to completely dissolve the fluorine release agent, and then add some solvents with good wettability to the substrate to assist leveling and adjust the volatilization rate. There is a solvent hazard during production, and the production price is high. As those skilled in the art, it is urgent to develop a novel polyester antistatic release film and a production method thereof.

Contents of the invention

The purpose of the present invention is to provide a kind of polyester antistatic release film and its production method for existing problems, and the present invention does not coat release agent on the surface of the film.

The present invention is realized through the following technical solutions:

A polyester antistatic release film, comprising a polyester composite film, the surface of the polyester composite film is not provided with a release agent, and the polyester composite film includes an inner layer, an adhesive release layer, an outer layer, The inner layer is an antistatic PET film, the outer layer is a porous PET film, and the polyester composite film is a three-layer structure prepared by coating and compounding an adhesive release layer, with a thickness of 25 to 150 microns; The production method of the polyester composite film includes the following steps: (1) corona on the surface of the inner PET film; (2) coating the adhesive release layer: the antistatic PET film is unwound at a tension of 40~60N, and the coating pressure is 2.5~ 3kg/cm ² , coating weight 2.5-3.5g/m ² , pressure roller temperature 70~75℃, to get glue-coated antistatic PET film; (3) drying; (4) composite: the dried glue-coated antistatic PET film PET film, coated with adhesive release layer; (5) Rewinding and aging: Rewinding speed 130~150m/min, rewinding tension 140~170N, after rewinding, the temperature is 40~50℃, relative humidity Mature at 50~75% for 36~48h.

Further, the adhesive release layer is uniformly mixed with 25-30% alcohol-soluble polyurethane, 2-3% polytrifluoropropylmethylsiloxane, 5-7% wax emulsion and denatured alcohol. Finally, add 1~2% methyl silicate, and finally add a crosslinking agent, mix well to obtain an adhesive release layer with a solid content of 20%~35%, where the crosslinking agent is organotin and water-based polyurethane curing agent According to the mixture of 1:1 by mass, the organotin is dibutyltin dilaurate or dibutyltin dilaurate, the water-based polyurethane curing agent is Aquolin270 or Aquolin278, and the wax emulsion is hydrogenated castor oil heated to 90~95℃, then Add 4-6% sodium dodecyl sulfonate of hydrogenated castor oil, and fully mechanically stir at 3000rpm to disperse and emulsify it to obtain a wax emulsion with a solid content of 10-12%.

Further, the drying temperature in the step (3) is 95-120° C., and the drying time is 2-3 seconds.

Further, the PET porous film has a pore diameter of 2-5 μm and a film thickness of 25-40 μm.

Further, in the step (4), the composite pressure is 0.1~0.2MPa, the composite speed is 130~150m/min, the traction pressure is 3~5kg/cm2, the preheating temperature is 40~50°C, the composite temperature is 60~70°C, and the cooling The temperature is 15°C, and the unwinding tension of PET porous film is 80~110N.

Further, in the step (1), the corona treatment voltage is 10-20kV, the frequency is 10-25kHz, the electrode spacing is 1-2mm, and the surface tension of the inner PET film reaches 45-50mN/m after corona treatment.

Beneficial effects of the present invention:

The production method of the polyester antistatic release film disclosed by the invention does not coat the release agent on the surface of the film, but adopts an adhesive release layer with dual functions, one of which is in the PET porous film of the outer layer and the inner layer The antistatic PET film, the adhesive release layer is used as an adhesive, so that the two are coated and compounded, and after curing, the release component of the adhesive release layer as the middle layer of the release film enters the PET porous film In the hole, a release effect is formed, and the size of the release force can be obtained by adjusting the PET porous film with different pore sizes. The preparation method is simple, and the polytrifluoropropylmethylsiloxane and tetraethyl orthosilicate can dealcoholize. , the molecular structure of tetraethyl orthosilicate can make polytrifluoropropylmethylsiloxane form a network cross-linked structure, and the curing agent can make polyurethane resin cross-linked and cured, and further improve the release ability, resulting in excellent mechanical strength The low surface energy substance, the adhesive release layer contains polytrifluoropropylmethylsiloxane, wax emulsion, and is compatible with the adhesive release layer in the presence of alcohol, at a temperature of 40~50°C and a relative humidity After curing at 50~75% for 36~48h, the volatilization of ethanol makes the polytrifluoropropylmethylsiloxane, castor wax and polyurethane resin not completely compatible, and slowly migrates to the porous PET film through the polyurethane adhesive. Inside, a uniformly dispersed release layer in the hole is formed, thereby reducing the force with the adhesive adhesive, so that the release film is not sticky or slightly sticky after contacting with specific materials under limited conditions, achieving the release effect .

Compared with the prior art, the present invention has the following advantages:

The polyester antistatic release film disclosed by the invention has a stable release effect, is environmentally friendly, has the characteristics of high tensile strength and tearing degree, small shrinkage rate, high anti-sticking force and the like. The surface is clean, no scratches, uniform coating, no transfer, small shrinkage, which has improved the problem of silicone oil residue pollution and solvent pollution of fluorine coating in the past. Polyester antistatic release film has high stiffness and smooth surface, especially When used as a film substrate, it has good heat resistance, is suitable for high-temperature gluing and dipping to remove dust, has good flatness, high cleanliness, high light transmittance, and stable release effect.

Description of drawings

Figure 1 is a schematic diagram of the structure of the polyester antistatic release film disclosed in the present invention, wherein 1 is the inner layer, 2 is the adhesive release layer, 2 is 3 outer layers, and 301-holes.

Detailed ways

The present invention is illustrated below with specific examples, but not limitation of the present invention.

Example 1

A kind of production method of polyester antistatic release film:

The polyester antistatic release film comprises a polyester composite film, the surface of the polyester composite film is not provided with a release agent, and the polyester composite film includes an inner layer, an adhesive release layer, an outer layer, and the inner layer The layer is an antistatic PET film, the outer layer is a PET porous film with an average pore size of 5 μm, a porosity of 45%, and a film thickness of 25 μm. The polyester composite film is a three-layer structure, which is prepared by coating and compounding; the production method specifically includes the following Steps: (1) Corona on the surface of the inner PET film: Corona treatment voltage is 20kV, frequency is 25kHz, electrode spacing is 2mm, surface tension reaches 50mN/m; (2) Coating adhesive release layer: DLFHG1400C high-speed The inner layer PET film is unwound on the first unwinding device of the gluing compound machine, the unwinding tension is 60N, the coating pressure is 3kg/cm ² , the coating amount is 3.5g/m ² , the pressure roller temperature is 75°C, and the scraper adopts a pneumatic back Pressing scraper; (3) Drying: Drying temperature is 120°C; (4) Outer layer on-line compounding: compounding pressure 0.2MPa, compounding speed 150m/min, traction pressure 5kg/cm ² ; composite heat roller Φ320mm, hard chrome oil plated on the surface Medium heat conduction, control composite temperature 70℃, Φ320mm preheating roller oil medium heat conduction, constant temperature control 50℃, cooling roller Φ320mm, 15℃ water circulation cooling, composite pressure roller is Φ150mm Shore hardness 90A rubber roller, second unwinding device Put a PET porous film on top, unwinding tension 110N; (5) Curling curing: winding speed tension 170N, 16100 (L) × 4000 (W) × 5000 (H) mm drying path length of 12 meters Tongpeiqi composite film The curing temperature in the curing room is 50°C, the humidity is 75%, and the curing time is 48 hours.

The adhesive release layer is composed of 30% alcohol-soluble polyurethane by mass percentage, 3% polytrifluoropropylmethylsiloxane _Mw 2400, 7% wax emulsion and industrial alcohol, and then add 2 % methyl silicate, finally add a cross-linking agent, mix evenly to obtain an adhesive release layer with a solid content of 35%, in which the cross-linking agent is organotin-dibutyltin dilaurate and Wanhua water-based polyurethane curing agent Aquolin278 is a mixture of 1:1 by mass, and the wax emulsion is heated to 95°C with hydrogenated castor oil wax, and then added sodium dodecylsulfonate with 6% quality of high-grade hydrogenated castor oil wax from Heiner Chemical Company, fully prepared at 3000rpm The wax emulsion with a solid content of 12% was obtained by mechanically stirring for 30 minutes to disperse and emulsify it. For the preparation method of the porous PET film, please refer to "Xipeng, Wang Yan. Effective regulation and pore-forming process of the surface porous structure of PET film [J]. Tianjin Industrial Co., Ltd. University Journal, 2021, 40(03):10-14".

Put PET resin slices and Juli anti-static agent WT4-4, which accounts for 1% of the mass of PET resin slices, into the CHD-75 twin-screw extruder. ℃, 220°C, 230°C, 240°C, 250°C, 260°C, 280°C, the speed of the main machine is 600r/min, and then mixed and extruded through a hanger-type die to form a cast sheet, and then stretched longitudinally, the temperature is 80°C , the stretch ratio is 9; transverse stretching, the temperature is 125 ° C, the stretch ratio is 8, and finally an antistatic PET film with a thickness of 40 μm is prepared.

Example 2

A kind of production method of polyester antistatic release film:

The polyester antistatic release film comprises a polyester composite film, the surface of the polyester composite film is not provided with a release agent, and the polyester composite film includes an inner layer, an adhesive release layer, an outer layer, and the outer layer The layer is a PET porous film with an average pore size of 2 μm, a porosity of 50%, and a film thickness of 40 μm. The polyester composite film has a three-layer structure and is prepared by coating and compounding; specifically, it includes the following steps: (1) corona on the surface of the inner PET film : The corona treatment voltage is 10kV, the frequency is 10kHz, the electrode spacing is 1mm, and the surface tension reaches 45mN/m; (2) Coating adhesive release layer: the first unwinding device of the DLFHG1400C high-speed gluing compound machine Layer PET film unwinding, unwinding tension 40N, coating pressure 2.5kg/cm ² , coating weight 2.5g/m ² , pressure roller temperature 75°C, scraper with pneumatic back pressure scraper; (3) drying: drying temperature is 95°C, 2s blowing time; (4) Outer layer online lamination: lamination pressure 0.1MPa, lamination speed 150m/min, traction pressure 3kg/cm2; lamination hot roller Φ320mm, hard chrome oil medium heat conduction on the surface, control lamination temperature 60 ℃, Φ320mm preheating roller oil medium heat conduction, constant temperature control 40℃, cooling roller Φ320mm, 15℃ water circulation cooling, composite pressure roller Φ150mm Shore hardness 90A rubber roller, PET porous film is placed on the second unwinding device, unwinding Tension 80N; (5) Curling curing: winding speed tension 140N, 16100L×4000W×5000Hmm drying tunnel length 12 meters Tangpei composite film curing room curing temperature 40 ℃, humidity 50%, curing 36h.

The adhesive release layer is composed of 25% alcohol-soluble polyurethane, 2% polytrifluoropropylmethylsiloxane (QF-1) M _w 4600, 5% wax emulsion and industrial alcohol in percentage. , then add 1% methyl silicate, and finally add a cross-linking agent, mix evenly to obtain an adhesive release layer with a solid content of 20%, wherein the cross-linking agent is organic tin-dibutyltin dilaurate and Aquolin270 water-based polyurethane curing The wax emulsion is made by heating the high-grade hydrogenated castor oil wax of Haina Chemical Company to 90°C, then adding sodium dodecyl sulfonate with 6% hydrogenated castor oil quality, and fully mechanically Stir for 20 minutes to disperse and emulsify the obtained wax emulsion with a solid content of 10%.

Among them, the antistatic PET resin chip CZ302 and Juli antistatic WT4-4 antistatic agent accounting for 1% of the mass of the PET resin chip are put into the CHD-75 twin-screw extruder. The barrel temperature is controlled in 9 sections, and the temperature is controlled at 180 ° C 195°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 280°C, the speed of the main machine is 500r/min, mixed and extruded through a hanger die to form a cast sheet, and then stretched longitudinally, the temperature The temperature is 85°C, the stretching ratio is 7; the transverse stretching temperature is 130°C, the stretching ratio is 6, and finally a sample is prepared with a thickness of 50 μm.

The polyester antistatic release film of Examples 1-2 was subjected to a performance test, and the test results are shown in Table 1.

The performance test result of the polyester antistatic release film of table 1 embodiment 1～2

project unit Example 1 Example 2 heat shrink MD % 15.8 14.3 Haze % 4.8 4.6 Transmittance % 68.6 69.3 Section flatness mm 3 3 breaking strength latitudinal) N 48.7 49.8 Elongation at break latitude % 12.5 13.4 breakdown voltage V 3242 3358 Peel force g/25.4mm 11.3g/25.4mm 10.6g/25.4mm Surface resistivity Ω 5.2×10⁷ 4.9×10⁷

Note: The heat shrinkage rate is measured according to the test method specified in GB/T12027-2004, and the light transmittance and haze are measured according to the test method specified in GB/T2410-2008; the width and end surface uniformity are measured by the corresponding precision vernier; Elongation rate; measured according to the test method specified in GB/T3923.1; the breakdown voltage is measured according to the test method specified in GB1408.1-2006; the appearance quality first visually inspects the quality of the film roll, and then takes a sample of 500mm from the full width of the end of the shaft diaphragm. The appearance quality of the film surface of the sample was visually inspected under the viewing lamp. Thickness and extreme difference in thickness Sampling at the end of the large-axis film, starting from 30mm from the edge of the film, grinding the film laterally to 3mm from the other side, measuring and recording the thickness of all points measured equidistantly with a thickness gauge with an accuracy of 1um, of which Take the average value as the thickness of the axis, and take the difference between the maximum thickness and the minimum thickness as the extreme difference of the axis thickness; paste TESA7475 pressure-sensitive tape on the silicon-coated surface of the silicon-coated polyester film sample to be tested along the MD direction, cut according to the size of the tape For a long sample with length×width=175mm×25.4mm, roll the sample 3 times with a 2kg roller. Use FPT-F1 peel tester, peel at 180°peel angle and 300mm/min speed, and read the peel force data; the test method of heat shrinkage rate is in accordance with GB/T16958-2008.

Claims (6)

1. a polyester antistatic release film, comprising a polyester composite film, is characterized in that the surface of the polyester composite film is not provided with a release agent, and the polyester composite film includes an inner layer, an adhesive release Type layer, outer layer, the inner layer is an antistatic PET film, the outer layer is a PET porous film, and the polyester composite film is a three-layer structure prepared by coating and compounding an adhesive release layer, with a thickness of 25 ~150 microns; the production method of the polyester composite film comprises the following steps: (1) corona on the surface of the inner layer PET film; (2) coating the adhesive release layer: the antistatic PET film is at an unwinding tension of 40 ~ 60N , coating pressure 2.5~3kg/cm ² , coating weight 2.5-3.5g/m ² , pressure roller temperature 70~75℃, to obtain glue-coated antistatic PET film; (3) drying; (4) composite: dry The final adhesive-coated antistatic PET film is coated and compounded with an adhesive release layer; (5) Rewinding and aging: Rewinding speed 130~150m/min, rewinding tension 140~170N, after rewinding, the temperature is 40 Mature for 36~48h at ~50℃, relative humidity 50~75%. 2. a kind of polyester antistatic release film as claimed in claim 1, is characterized in that, described adhesive release layer is made of 25 ~ 30% alcohol-soluble polyurethane, 2 ~ 3% polystyrene by percentage. Fluoropropyl methyl siloxane, 5~7% wax emulsion and industrial alcohol are mixed evenly, then add 1~2% methyl silicate, and finally add cross-linking agent, mix evenly to obtain a solid content of 20%~35 % adhesive release layer, wherein the cross-linking agent is a mixture of organotin and water-based polyurethane curing agent in a mass ratio of 1:1, and the organotin is dibutyltin dilaurate or dibutyltin dilaurate, water-based polyurethane curing agent It is Aquolin270 or Aquolin278. The wax emulsion is the solid content obtained by heating hydrogenated castor oil to 90~95℃, then adding sodium dodecylsulfonate with 4~6% hydrogenated castor oil quality, and fully mechanically stirring at 3000rpm for 20~30min. 10~12% wax emulsion. 3. The polyester antistatic release film according to claim 1, characterized in that the drying temperature in the step (3) is 95-120°C, and the drying time is 2-3s. 4. The polyester antistatic release film according to claim 1, wherein the PET porous film has an average pore diameter of 2 to 5 μm, a film thickness of 25 to 40 μm, and a porosity of 40 to 50%. 5. The polyester antistatic release film according to claim 1, characterized in that, the composite pressure of the step (4) is 0.1~0.2MPa, the composite speed is 130~150m/min, and the traction pressure is 3~5kg/min. cm ² , preheating temperature 40~50°C, lamination temperature 60~70°C, cooling temperature 15°C, PET porous film unwinding tension 80~110N. 6. The polyester antistatic release film according to claim 1, characterized in that, the step (1) corona treatment voltage is 10~20kV, the frequency is 10~25kHz, the electrode spacing is 1~2mm, and the voltage is 1~20kV. After dizziness, the surface tension of the inner PET film reaches 45~50mN/m.

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