Jelly glue (also known as animal protein glue) is a safe and environmentally friendly glue. Because it is made of natural and environmentally friendly materials and water is added as a solvent when used, the bonding effect is better than water-based glue. It is not easy to penetrate the paper and cause deformation. Therefore, it is deeply loved by printing and packaging manufacturers such as hardcover gift boxes, packaging boxes, and hardcover book covers. Below, I will tell you how to judge the quality of jelly glue:
1.Testing the fluidity of jelly glue
To test the fluidity of jelly glue, you can put the glue on a flat transparent glass, shake the glass left and right, and observe the flow of the glue. If it flows faster, it means that the glue is too thin; if the glue flows slowly or cannot flow at all, then this glue is not convenient for bonding. Secondly, use two fingers to stick a little glue and slowly separate them. If a drawing effect can be slowly produced, it proves that the initial bonding strength of the glue is good. Therefore, a good jelly glue must have a drawing and sticky effect.
2.Testing the film-forming effect of jelly glue
To judge the film-forming effect of jelly glue, you also need to take a little glue and put it on a flat glass. If a thin layer of glue film can be formed on the surface within 1-2 minutes, it means that the quality of the glue is good. At the same time, leave the glue after film formation for a while. When the glue is completely solidified, wipe it with water. If the glue is quickly dissolved, it means that the cohesion of the product is poor; and observe whether the glue is turbid. If there is no debris inside, it means that the quality of the jelly glue is good.
3.Testing the bonding strength of jelly glue
To test the actual bonding strength of the glue, you can use the melted glue to glue two pieces of cardboard together, put them in a cool place to cure for 24 hours, and use a tensile tester to test the tensile force and material breaking effect of the glue. If the paper can be broken, it proves that there is no problem with the bonding strength of the glue.
4.Testing the water resistance of jelly glue
To test the water resistance of jelly glue, soak the bonded cardboard in water for some time and then dry it. Observe whether the seal of the paper box bounces open. If not, it means that the jelly glue has good water resistance.
5.Testing the high and low-temperature resistance of jelly glue
If you need to test the glue’s resistance to high and low temperatures, you can use the same method as above, put the paper box in the refrigerator and oven (it would be better if there is a hot and cold cycle machine) to test whether it pops open. If it does not pop open, it means that the glue has good resistance to high and low temperatures.
If all the above five methods can be successfully passed, it proves that the quality of the jelly glue you choose is very good.