The so-called PP Bag is made with polypropylene as the material of plastic bags, its general use of color printing, offset printing process, bright colors, generally do more woven bags, in addition, PP bag is tensile polypropylene plastic, belongs to a thermoplastic.It is non-toxic, tasteless and transparent.Easy to burn, flame for melting dripping, yellow under blue, from the fire smoke less, continue to burn, more used for cosmetics, food, toys, clothing, stationery, electronics, hardware products and other industries packaging.The color is transparent, good quality, good toughness, because of its hard brittle material decided that it is only suitable for packaging is not suitable for load-bearing. Pp Plastic Bag,Pp Handbag,Pp Shopping Bag,Polypropylene Packaging Bags Wenzhou Shandao Electronic Commerce Co., Ltd. , https://www.reusablebaglife.com
Phenomenon: The packaging printing ink or even printing plastic ink is printed in the packaging for a period of time (especially when the temperature is high), because the surfactant-containing ink is deposited on the outside of the film or migrated to many bottom substrates. . If the ink migrates to the product after packaging, the phenomenon of migration is called. Infiltration is often due to the fact that the active agent-containing resin (too small viscosity) in the ink system accelerates the penetration of the pigment and the dye inward. Poor gloss, dullness of the ink film, which is often encountered in most inks. Sometimes the dilution is added during the printing process, or using the wrong solvent will also show this phenomenon.
Reason: 1 is the migration of resin in the ink system caused by the free, especially the thermoplastic resin binder material has a softening point is too low or the environment temperature is too high to cause the migration or deformation; 2 is the penetration often refers to the packaging printing ink system Infiltration caused by the characteristics of the dye, but also because the substrate itself is not resistant to penetration, followed by too little ink resin connection will also cause infiltration. In particular, the turbidity caused by the unbalance of the solubility between the solvent and the resin makes it impossible to perform the pigment particle tightly on the surface of the (resin liquid) coating during the competitive adsorption, and as a result, the pigment penetrates into the substrate. On the back; 3 is due to the substrate is not smooth, too rough or too thin and easy to penetrate the poor gloss, but also due to the packaging printing ink in the binder (resin) content is low or resin and solvent solubility is not good (opaque, cloudy , color is too light) and so on.
Method: 1 Add amphoteric resin or a suitable amount of hard resin (high softening point or thermosetting resin); 2 Add thickener or increase the content of resin; 3 Can add cheap salt or leveling coupling agent due to poor gloss Yes; 4 Adding film-forming lightening aids; 5 Increasing printing power; 6 Coat a coat of coating oil.
Poor migration, penetration, gloss