The Quality Of The Release Paper Is The Key To Affect The Quality Of Die Cutting

The thickness, flatness, fiber structure and strength of the release paper directly affect the quality of die cutting. 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 material is generally above 90g/㎡, with a certain stiffness, suitable for sheet paper printing, but also suitable for web printing, and the finished product label is mostly used for manual labeling.
Transparent release paper pressure sensitive adhesive material quantity is generally 60-70g/㎡, release paper fiber has a certain density or tightness, mainly used for web printing, not suitable for sheet paper printing, finished product label for automatic labeling.
The pressure sensitive adhesive material requires the release paper to have good flatness, uniform thickness, consistent overall transmittance, and the greater the density, the better, in order 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 is divided into two kinds: pre-coated PE coating and without 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, coated with silicone oil, reduce the amount of coating, can reduce the cost;
B, another role is to improve the die-cutting characteristics, because the PE coating is equivalent to a layer of buffer cushion, has a certain toughness and elasticity, can reduce the break of the release paper. Practice shows that the fracture resistance of release paper with PE coating is much lower than that of release paper 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, such as continuous die-cutting, manual waste will be uncovered together with the label; If the release paper is cut through or cut through half, the operator is also very difficult to uncover the label. When the opaque release paper is die-cutting on the flat die-cutting machine, the common fault is that the release paper is broken, so on the basis of ensuring the accuracy of the die-cutting tool and the flat liner, the 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, die-cutting pressure-sensitive adhesive materials commonly used Glasin release paper (glass release paper).
Glasin release paper has two indicators that will affect the quality of die cutting: one is the uniformity of thickness and the other is the fiber structure. Among them, the uniform thickness of the release paper is the most important, especially when the die cutting is circular pressing, because the size of the die cutter roll is determined by the thickness of the release paper, if the thickness of the release paper is not uniform, the blade will cut through or not cut the release paper, which brings trouble to the waste discharge process. The fiber structure of Glasin release paper mainly affects the die cutting speed for circular die cutting, because the fiber strength directly affects the breaking speed of waste discharge, and the faster the speed and the greater the tension, the easier the waste discharge. If the strength of the material itself is large, the die-cutting speed can be increased. 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 has a very large impact on the quality of die-cutting, and the release paper with good fiber toughness may not be a problem on the equipment with low precision, but if the fiber of the release paper is brittle and poor toughness, it can only be die-cutting on the equipment with high precision and good die-cutting quality, which shows that the equipment accuracy is also one of the factors affecting the quality of die-cutting.
There are two pressure-sensitive adhesive materials with the same substrate and different release paper, which are processed at the same time on two label equipment, and the result is die-cutting on the equipment with high precision, and the die-cutting quality of the two materials is normal; In the equipment with low precision die-cutting, the materials with poor toughness of the release paper fiber often have problems and cannot be produced normally. This case shows that the quality of die cutting is related to the pressure-sensitive adhesive material itself, and is also related to the accuracy of the equipment.