Recently, Steven received feedback from some customers: your adhesive strength is not good, it is not firm, it will be curly after one night.Is the quality of adhesive not good?

At first, Steven think the factory production is not strict, the ratio is not enough.At one point, the factory was shut down for inspection.Reflect on why this is the case.

With the occurrence of this kind of problem in quick succession recently, and be limited to a few printing houses to appear,customer is to produce packing bottle.And that got me thinking.

 

First, let's analyze the culprit: adhesive

The composition of adhesive is generally divided into two kinds: A water adhesive B hot melt adhesive.

Water glue, needless to say, it is a kind of with water as solvent or dispersion medium glue, the glue initial adhesion is not so good, is what you call a sticker at first not so strong, this is due to the properties of glue, the glue is not very strong at first, but with the development of the time, the label will become more and more strong, the longer, the more viscous.

Hot melt adhesive, the old printing people should know better than I, is a kind of plastic adhesives, to a certain temperature range with the temperature change and change its physical state, used this glue labels, strong initial adhesion, attach is the beginning is very strong, but with the increase of temperature and time, viscosity slowly becomes weak, this glue is affected by temperature and time.

So, is it because I used a water-based sticker, which makes the label not sticky enough?

In fact, it is not certain, let's take a look, what is the general situation of the label viscosity is not enough, the case of the standard?

1. Plastic bottles.

Generally choose manual label customers, are manufacturers, plastic injection molding, down the production line, it is about to start labeling.

Let's take a look at a chemical that is essential in the production of injection-molded plastic bottles: Release agent.

What is the release agent?

It is a functional substance between the mold and the finished product.Release agents are chemical resistant and do not dissolve in contact with the chemical components of different resins, especially styrene and amines.Release agent also has heat resistance and stress properties, not easy to decompose or wear;

Properties: It is an interfacial coating applied to two surfaces that adhere easily to each other. It makes the surfaces easy to detach, smooth and clean.

2, the varnish

Also known as where water, resin is the main film material plus solvent composition of the paint.Because coating and besmear are transparent, also call transparent coating accordingly.Coated on the surface of the object, dry to form a smooth film, show the surface of the original texture.

Properties: A smooth protective layer on the surface of an object.

3. Others

The finished products just printed will be sprayed with talcum powder and other items, such as the factory cabinet will also be sprayed with oil protection solution.

These situations will appear adhesive paste is not strong.

The chemical composition of the glue usually contains vinyl acetate, varnish or release agent usually contains xylene and silicone oil.One of these components will break down the glue, and the other will not react with it.In addition is to be pasted on the surface of the object there are other dust or protective liquid, so that the adhesive and the object cannot be fully adhesive.

Also appeared the problem that we worry all the time: sticker not sticky

So how do we deal with this situation?

It's simple: clean the surface.