1.The release paper is easy to tear off when pasting, but it is difficult to peel off after one cycle (24 hours), and it can't be pulled off after three cycles.

Such release paper is mainly unstable. The paper density is poor, the coating is uneven, and its anti permeability is poor. Therefore, when pasting for one cycle, the glue can penetrate into the release paper, so it can't be peeled off! Therefore, the paper with better density, better paper, uniform silicon coating and more stable paper must be replaced as the base paper.

2.Poor peeling of imported double-sided adhesive tape

Many tapes have this phenomenon, because the physical properties of imported double-sided tapes are different. There are substrates with or without substrates. Many manufacturers use a base paper for die cutting for convenience, resulting in poor peeling. Therefore, we must judge the viscosity of the tape and use the backing paper separately when the viscosity difference of the tape is relatively large.

3. Usually used to paste this tape can be, but it is difficult to discharge waste after die-cutting, or because the product is too small to peel off.

We should pay attention to this situation. Some products are easy to bring up in the waste discharge process, which shows that the stripping force is too light. You can choose a slightly heavier one to try. If it is impossible to peel or poor peeling, it is also normal (especially those without substrate). Because the product area is too small, it is easy to cause deformation when the peeling force is not light enough, so lighter release paper must be used.

Many users now reflect this phenomenon. In fact, release paper cannot judge the essence of release paper completely by the release force at the beginning, because different coating methods and different base paper will have different release force cycles, as well as the impermeability of release paper. There is another kind of grasin on the market, which is coated with wax silicone oil, and the surface is very beautiful, And at the beginning of fitting, the release force is very light, but it can't be torn off after a few days.

Therefore, it is recommended to use genuine glasin instead of those disorderly codes. The adhesive property of 3m9460 is relatively sticky, and the release paper must be evenly coated and light release paper. It is recommended to use solvent-free silicon release paper. When selecting release materials, we should do three cycles of test, and we should do 15 days of high temperature and high humidity test. Only through such strict requirements of release paper, it is a truly reliable release paper.

The quality of release paper is the key to the quality of die cutting

The thickness, flatness, fiber structure and strength of release paper directly affect the die-cutting quality. At present, the commonly used release paper is divided into two categories:

1. Opaque release paper and translucent release paper;

2. The quantity of opaque release paper pressure-sensitive adhesive is generally more than 90g / ㎡ and has a certain stiffness. It is suitable for single sheet printing and web printing. Finished labels are mostly used for manual labeling.

The quantitative content of transparent release paper pressure-sensitive adhesive is generally 60-70g / ㎡. The release paper fiber has a certain density or tightness, which is mainly used for web printing, not suitable for single sheet printing, and the finished product label is used for automatic labeling.

Pressure sensitive adhesive materials require release paper with good flatness, uniform thickness, consistent overall light transmittance, and the greater the density, the better, so as to facilitate the complete die-cutting of the substrate.

1. Opaque release paper

The commonly used opaque release paper is distinguished by color: it can be divided into yellow and white; According to the structure, it can be divided into pre coated PE coating and non PE coating.

PE coating has two purposes:

A. It is to seal the pores on the surface of the paper to make it smooth and flat, and apply silicone oil on it to reduce the coating amount and reduce the cost;

B. Another function is to improve the die-cutting characteristics, because the PE coating is equivalent to a layer of buffer pad, which has certain toughness and elasticity and can reduce the fracture of release paper. The practice shows that the fracture resistance of release paper with PE coating is much lower than that without PE coating.

Because the thick release paper label is mainly used for manual labeling, the unqualified die-cutting quality has a certain impact on the manual labeling. If the die-cutting continues, it will be removed together with the label when manual waste discharge; If the release paper is cut through or cut through half, it is also very difficult for the operator to uncover the label.

When the opaque release paper is die cut on the flat press die-cutting machine, the common fault is that the release paper is broken. Therefore, on the basis of ensuring the accuracy of the die-cutting knife and the flatness of the pad, release paper with good flatness, large fiber tension and uniform thickness should be selected as far as possible to improve the die-cutting quality.

2. Translucent release paper

Translucent release paper is also called thin release paper. At present, grasin release paper (glass release paper) is commonly used for die-cutting pressure-sensitive adhesive materials.

Grasin release paper has two indicators that will affect the die-cutting quality: one is the thickness uniformity, the other is the fiber structure. Among them, the thickness uniformity of release paper is the most important, especially in circular die cutting, because the size of die-cutting knife roller is determined by the thickness of release paper. If the thickness of release paper is uneven, the blade will cut through or can not cut the release paper, which will bring trouble to the waste discharge process.

The fiber structure of grasin release paper mainly affects the die-cutting speed for circular die-cutting, because the fiber strength directly affects the waste discharge fracture speed. The faster the speed and the greater the tensile force, the easier the waste discharge is. If the strength of the material itself is large, the die-cutting speed can be improved. However, for the slow flat die-cutting, the fiber structure has little effect on the die-cutting quality. In addition, the toughness and fracture resistance of the fiber have a great impact on the die-cutting quality. For release paper with good fiber toughness, there may be no problem in die-cutting on equipment with low precision. However, if the fiber of release paper is brittle and poor toughness, die-cutting can only be carried out on equipment with high equipment precision and good die-cutting quality, which shows that, Equipment accuracy is also one of the factors affecting die-cutting quality.

There are two pressure-sensitive adhesive materials with the same substrate and different release paper, which are processed on two label equipment at the same time. As a result, the die-cutting quality of the two materials is normal on the equipment with high precision; In the low precision equipment, the materials with poor fiber toughness of release paper often have problems and cannot be produced normally. This case shows that the die-cutting quality is related to the pressure-sensitive adhesive material itself and the accuracy of the equipment.