Selection of Adhesives for Packaging and Analysis of Common Quality Problems (I)

Caused by "difficult to bond"

With the progress of social civilization and the demand of the market, more and more new materials and processes have been applied to the packaging industry, and bonding has become an important material that combines the complete packaging of a product and is increasingly used. In the packaging industry, during the process of domestic production and sales of various printing and packaging adhesives, we have had many contacts with many domestic printing and packaging companies. During this contact process, we have discovered that many manufacturers (Including some large-scale printing and packaging plants), they are experts in printing, but the understanding of viscose is not enough, many of them are even blind in selecting and using adhesives, and this brings them to all manufacturers. Big losses and waste. "Difficulties in bonding" has become a specter that has plagued packaging companies, causing headaches for almost every packaging and printing factory.
Our company is a professional manufacturer of printing and packaging adhesives. We believe that as long as you choose and use good adhesives, the problem of “difficult bonding” can be completely solved. Combining the experience and lessons of many manufacturers, the problems are in the "select, use" these two links, in order to allow many engaged in technical work, quality management, supply work counterparts to learn more about adhesives, so that "bonding difficult" It became “Easy Bonding”, from “Worrying Plastics” to “Resting Plastics.” We compiled this handbook to discuss the production and use of adhesives with our domestic counterparts and make our country’s packaging industry prosperous. contribution.

How to choose adhesive

Understand the use of properties Any adhesive is not a panacea, a type of adhesive can only be suitable for a certain or a certain type of sticky material. Some manufacturers use the "pick a try" mental blind glue, which wastes time and energy, but also cause great losses. Nowadays, BOPP/paper, polishing/paper, PET/paper, and high-light printing paper/paper are commonly used in various packaging factories. In fact, this kind of product only needs one kind of product from our company, that is, 810 sealing glue. Colloids can adapt to all the requirements of the above products, and 98% of all packaging companies are the above ones. In addition, there are some manufacturers such as PVC / paper, PVC / wood, UV / paper, etc. These products can be used to solve other models of our company's plastic. (such as PVC glue, 818UV special sealing glue)

2) Quality standards

As an adhesive, the most important quality standards: A, adhesive strength (adhesion); B, high temperature resistance; C, low temperature resistance; D, aging resistance; E, adhesive strength retention. Many domestic packaging plants appear to have poor adhesion or brittle products for a period of time. Degumming is basically the same as above. Therefore, some printing and packaging factory counterparts often say that “some gels degumming days, some gels degummed in cold days, and some glues do not store in cold or hot weather for a long time” This statement is actually a profound understanding of the quality standards of plastics. As a result, even some factories that manufacture viscose do not know why they are degumming, so it is not surprising that there are quality problems in the production process.

3) Performance

Our 810 sealing glue and 818 sealing glue are miscellaneous multifunctional paper-plastic adhesives with strong initial adhesion, high bonding strength, good resistance to high and low temperature, good adhesion and retention, good moisture resistance and wide range of bonding. Only one or two kinds of plastics basically meet all the bonding requirements of the current packaging factory (BOPP/paper, polishing/paper, PET/paper, UV light/paper, ink/ink), and are welcomed by many manufacturers. The disadvantage of miscibility is that the cleanability of the container utensils is somewhat poor, and the wild glue is wiped with a solvent (due to good moisture resistance). Therefore, when choosing viscose varieties, manufacturers should understand the characteristics and performance of each variety and adapt to their actual conditions. At the same time, we must also have a certain understanding of the production plants that provide viscose, such as whether the products are mature, the stability of the products, the understanding of the products, and the technical strength. Otherwise, the blind use of plastic is a great hazard, because the viscose products have hysteresis, many degumming is only a few days or even months later, so the use of plastic must be careful.

4) Price

Select adhesives, quality is certainly the first, the price second. Some manufacturers blindly believe that the higher the price is, the better the quality is, or the lower the price is, the worse the quality is. These views are very one-sided, and therefore some manufacturers have both spent money and caused great losses. In fact, viscose only occupies a small proportion of the cost of a packaged product. Therefore, we believe that firstly, under the premise of understanding product characteristics, understanding quality standards and performance, we should seek a suitable price. We think this is reasonable.

Adhesive properties and inspection methods for sealing glue

A batch of finished packaging boxes is not immediately used, and it is sometimes possible to stock a few months or even a year. Therefore, it is very important for an adhesive to have good cold and heat resistance and good aging resistance. For example, some packaging boxes work well for a short period of time, and after a period of time, degumming and film brittleness have occurred. So in the end to determine a kind of adhesive bonding performance in the end how to do the following aspects of the test.

First, tear a tear on the bonded package along the edge to see if it is torn by the adhesive substrate and apply a nail to the paper base attached to the film. If only a small piece of paper can be removed at a time The lack of paper base on the base or simply indicates that the adhesive has good adhesion on the film. Plastic/plastic sealing glue Because the two adhered surfaces are BOPP film, the film can not be destroyed due to its strong flexibility, so it can be felt that the two adhered surfaces have strong adhesive force during inspection.

Second, the bonded packaging box (at least one day has been placed) placed in a thermostatic oven at 60 °C baked for 72 hours out of the cooling after the seam or bottom does not pop open, while the hands do not degumming the packaging box, The film was not brittle, indicating no problem with the heat resistance of the adhesive.

Third, put the bonded packaging box (at least one day has been placed) in the freezer of the refrigerator and freeze it for 72 hours. After the box is dry, the box is not degummed and the film is not brittle. The adhesive has no problem with low temperature resistance.

Fourthly, the adhesive products adhered by the first three kinds of adhesives will be stored. Some samples will be tested every two weeks, one box will be tested, the hands will not be debonded, the film will not be brittle, and there will be no problem during the continuous inspection for six months. The glue can be used with confidence.