The use of water-based adhesive points of experience

Shishi Xinguang Company began to formally use Rohm and Haas's water glue two years ago. The main purpose is to reduce the transfer of aluminum film and shorten the lead time. Compared with solvent glue, the operation of water glue is relatively simple, but also pay attention to some points of the control process.

1. Since the amount of glue on the glue is very small, the glue roller must select the dense and shallow laser-engraved roller, usually 200 lines/35U. The mesh shape of the laser roller is relatively large, so that the glue can be better Transfer to film.

2. Before using the glue, be sure to slowly stir the glue in the barrel for 5-10 minutes to ensure that the additives in the glue are mixed evenly.

3. Before testing the surface tension of the film, it is better to use dyne solution instead of Dyne. The surface tension of the film should be at least 38 dyne, and the surface of the ink should also be tested. Some inks have lower surface tension.

4. As far as possible, a counter-rotating homogenizer roller was used, and it was observed in actual production that the reverse flattening stick had a great influence on the appearance, and the appearance could be optimized by adjusting the speed. The oven temperature is set to 80% - 85% - 95% (the temperature can be turned on after setting temperature).

5. The air inlet and exhaust of the oven should be maximized, and the contribution of the air volume to the water-based glue drying will be more important than the temperature. The compound hot drum temperature is set to 75~C—85~C, and the compound hot drum pressure is maximized. Note: The temperature setting, in consideration of the bearing capacity of the film and process, should try to operate according to the above recommended conditions.

6. An air diaphragm pump must be used between the glue tank and the glue tank. Clean the pump before use. Do not mix with the solvent.

7. To prevent jamming, the scraper must be released when the machine is shut down, and the rubber roller is soaked in the glue to keep it rotating.

8. If the speed is too high, air bubbles will be generated. You can put a uniform ink stick in the glue tank.

9. After use, wipe off the glue on the glue roller with water and then thoroughly wash with ethyl ester. If it has been blocked, it needs to be cleaned with butanone.

10. The storage temperature of the glue should not be lower than 5~C, it should not be exposed to the sun, and it must not be contaminated by dirt, solvents, etc.

11. If there are scratches on the surface, generally there are two points of attention: First, the scraper is not clean, resulting in scraping phenomenon, cleaning scraper; second is blocked version, clean version of the roller.

Since water glue bonds the two films together through the principle of film formation, its compounding effect is very stable, and the resulting product can be slit immediately. If the quality of the composite is not good because of the process or the substrate, the electricity can be seen in the first time after the machine is down, and the problem will not be discovered after mass production. After two years of use, our company believes that water-based adhesives have a great advantage over traditional solvent-based adhesive aluminum-plated aluminum films. Recently, we have begun to attempt to apply more two-component water adhesives to more structures.

(author/Cai Chunfeng)

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