Abstract: This paper introduces a new two-component water-based polyurethane adhesive, which has obvious cost advantages over solvent-based adhesives, and has better initial adhesion and low temperature resistance (freezing resistance) when composite products are used. .
Two-component water-based polyurethane adhesive is a new type of solvent-based two-component polyurethane adhesive product newly launched in 2013. Is a truly green type (VOC emissions are zero), production environment-friendly (completely eliminates the solvent pollution to the production environment and the harm to production workers) and product safety (the residual solvent in the composite process is truly Zero) products.
The successful development of the two-component water-based polyurethane adhesive is a breakthrough change to the traditional solvent-based composite process.
I. Comparison of water-based polyurethane adhesives and solvent-based polyurethane adhesives
1. Compared with water-based polyurethane adhesives and solvent-based adhesives: under the condition that the composite equipment is unchanged and the process conditions are basically the same, there is no solvent residue in the flexible packaging composite products, and the workshop production environment is completely improved.
2. Because its solid material part is polyurethane series, it has the properties of solvent-based polyurethane adhesive. Water-based polyurethane adhesives can provide the properties of solvent-based two-component polyurethane adhesives on flexible packaging ordinary materials, composite materials such as boiling and freezing.
3. Compared with solvent-based adhesives, it has obvious cost advantages.
4. Compared with solvent-based adhesives, composite products have better initial adhesion and low temperature resistance (freezing resistance).
Comparison of water-based polyurethane adhesives and water-based acrylic adhesives
1. Water-based polyurethane adhesives have the advantages of safety, environmental protection and no solvent residues of water-based acrylic adhesives currently on the market.
2. Water-based polyurethane adhesive is different from water-based acrylic adhesive. Because it is different from the acrylic material system, it makes up for the limitations of the water-based acrylic adhesive that can only be used for light packaging and rolls and bag making, and the poor high and low temperature resistance.
3. Compared with water-based acrylic adhesives, water-based polyurethane adhesives do not suffer from post-complex strength attenuation (generally there will be an increase).
4. Compared with water-based acrylic and alcohol-soluble adhesives, water-based polyurethane adhesives have better adaptability to inks and substrates, and the compound effect on some substrates is higher than that of solvent-based adhesives.
Comparison of cost between water-based polyurethane adhesive and solvent-based adhesive
1.The current price per ton of water-based polyurethane adhesives ≈ the price per ton of ordinary solvent-based adhesives
2. The coating areas of the two are roughly equivalent: the dry coating amount of water-based polyurethane adhesive is 0.8 ~ 1.2g / ㎡, so the coating area per kilogram is about 375 ~ 250㎡; solvent-based polyurethane adhesive dry coating The amount of cloth is 2 ~ 2.5g / ㎡, so the coating area per kilogram is about 375 ~ 300㎡;
The use of solvent-based adhesives requires an additional 1 to 1.5 kg of ethyl acetate per kilogram of adhesive; and water-based polyurethane adhesives can be directly coated using only an anilox roller with 180 to 200 lines.
Note: The above are only theoretical comparisons. There will be errors in actual production, so the actual use results shall prevail.