Characteristics and application of the hottest gCx

GCx film material: characteristics and applications

gCx film is a new self-adhesive surface material introduced by Avery Dennison company to the global label industry in 2006. Due to the special properties of the product, the material was immediately praised by printing plants and end users as soon as it entered the market. At present, among users in North America and Europe, gCx film has become one of the preferred materials for printing and processing film self-adhesive labels. The following article gives a brief introduction to gCx materials from the aspects of material structure, printing processing characteristics and applications

I. Basic Structure

gcx film is formed by mixing polyethylene (PE) and polypropylene (BOPP) resins in a certain proportion and stretching in one direction after coextrusion. It is a kind of polyolefin material. The manufacturing principle is shown in Figure 1. GCx belongs to three-layer coextrusion in structure, namely printing layer, middle layer and bottom layer

1. The printing surface of the printing layer

is foggy matte effect, and the principle of this effect is; After the film reaches a certain deformation by unidirectional stretching, tiny and uniform holes or wrinkles are formed on its surface. These holes or wrinkles have different reflectivity, so they form a fog or matte effect visually

another effect of these holes or wrinkles is to improve the wettability of the film surface to the ink. No matter what kind of ink, whether it is thin ink layer or thick ink layer, whether it is dot printing or field printing, the ink can be easily combined with the surface of the material, and can fully reflect the color characteristics of graphics and texts. If printed after online corona treatment, the printing characteristics of the film surface will be improved

the printing layer is composed of two types of components; The crystallized hard part provides the heat resistance, die cutting impact resistance and tensile strength of the material, while the other part is a soft filling part, which makes the surface suitable for various printing and processing technologies, whether UV ink or water-based ink, hot stamping, cold stamping or heat transfer printing, can achieve the best application effect

2. Middle layer

the middle layer is the supporting part of the material, with a very hard resin layer, which is used to maintain the tensile strength and hardness of the overall material, so that the material will not shrink or deform in the machine direction during printing and labeling, and remain firm. It is easy to break during die-cutting, making it easier to print positioning, die-cutting processing and labeling applications

at the same time, there is also a part of soft resin in the middle layer, which is combined with the crystallized resin as a buffer or linker. The function of buffer is to maintain a certain softness of the middle layer, and the function of linker is to make the middle layer have a good connection with the printing layer and the bottom layer, so as to make it become a whole. At the same time, the resin in the soft part can also improve the friction strength of the whole material and improve the die-cutting characteristics of the material in the direction perpendicular to the machine

3. Bottom layer

bottom layer has two functions; First, there is a good chemical connection with the adhesive, so that the adhesive can be evenly coated on its surface, without shrinkage, foaming and falling off during application. Another function is to cooperate or assist the intermediate layer to maintain the hardness and tensile strength of the overall material, so that the material has good die-cutting and labeling characteristics after printing

therefore, the composition of the bottom part of the material is also mostly composed of crystalline and hard resin

II. Material characteristics

since gCx material is formed by heating, melting and coextrusion of PE and BOPP resins, it has the dual characteristics of PE and BOPP materials at the same time

1. The visual effect before and after printing and polishing

gcx is matte fog effect in the original state of the material. As mentioned above, this is because the material strengthens the exchange and cooperation inside and outside the province, at home and abroad. After stretching and deformation, there are small holes or wrinkles. Matte foggy materials can be directly applied to the surface of matte and pearlescent bottles without glazing after silk printing. At this time, the gloss of gCx surface is almost the same as that of the bottle surface. In order to pursue this effect, some foreign products often use the method of making labels without polish on the surface of materials

however, in order to protect the ink layer, UV varnish is usually applied on the surface of the ink layer. If customers continue to want to get matte effect on the label surface, they can directly apply matte UV varnish. If the customer wants to get a bright effect, the material immediately changes in essence after using a bright varnish, that is, the surface with matte fog effect becomes a bright, almost completely transparent material

what is the reason? At this time, because the transparent glazing oil flattens the pores or wrinkles on the surface of the material, its reflectivity is consistent, forming a mirror effect. At the same time, the resin in gCx material formula is close to transparent, so the material looks almost transparent. Use a metaphor; It's like a piece of transparent frosted glass. It looks like matte fog at ordinary times, but after the surface is watered, the glass becomes fully transparent

Figure 3 shows the transparency of transparent gCx material before and after polishing or laminating with other materials. It is obvious that; Before the glazing of gCx, the degree of calendering atomization was stronger than that of transparent PE materials, while at present, the transparency of graphene used by enterprises in the textile field was higher than that of PE and close to that of BOPP materials

with this feature of gCx material, customers can get two appearance effects of the same material - bright and matte, two different styles of labels and two choices

2. Printing die-cutting characteristics

the matte atomized surface of gCx material is suitable for printing and bronzing in various printing methods. The porous surface makes the ink easy to level, whether it is silk printing with thick ink layer or lithography printing with thin ink layer. When printing, online corona treatment can greatly increase the firmness of the ink layer, so we recommend online corona treatment when printing

the gCx material after unidirectional stretching has strong tensile strength in the machine direction. Because the molecular lattice in the material has been deformed and solidified, this material structure will not cause the deformation of the material in the machine direction during the printing process, whether it is the change of speed or the change of drying temperature, so the printing overprint is accurate and high precision

as mentioned above; GCx material contains some hard BOPP resin, and according to different needs, we must speed up technological progress and scientific and technological innovation in different proportions. The cloth is in the printing layer, middle layer and bottom layer. This structure enables the die-cutting pressure to be appropriately reduced during die-cutting, and the blade can smoothly cut the section layer, pass through the hard middle layer, and finally stop after cutting the bottom layer

due to the good fracture characteristics of the material, there will be no undercut of the surface material and cracking of the bottom paper. According to the experience of CCL label printing factory in the United States, the die-cutting pressure is reduced from 55bar to 14bar after using gCx

3. Application characteristics

gcx material is very strong in the direction of the machine because of its directional stretching during production and a large amount of hard resin. Compared with other materials, it can be processed into relatively thin materials. After being processed into labels, the automatic labeling is very smooth, even when the initial adhesion of the material is large and the peeling force between the same backing paper is high. This is one of the most important characteristics of gCx material

gcx materials are mainly used in the daily chemical industry, and the packaging bottle bodies of many products in the daily chemical industry need to be extruded. Therefore, the label material is required to be able to deform with the deformation of the bottle body during extrusion without wrinkling and warping. GCx material can be deformed elastically in the other direction due to its unidirectional tensile deformation, so it can meet the requirements of bottle extrusion, such as the tensile test of woven bags, the tensile test of rubber and the experimental deformation of metal materials. This is another feature of gCx material

gcx material is compared with other thin film materials in terms of elastic deformation capacity; PE material has the best follow-up performance, while BOPP has the worst follow-up performance, and gCx is between the two

III. application scope and overall value of materials

1 Application range

gCx material has the softness and follow-up of PE material, and is superior to PE in matte atomization effect and printing processing adaptability. At the same time, it has the firmness and transparency of BOPP material, but it is stronger than BOPP in softness and follow-up in application. Therefore, gCx material is suitable for different types of bottle bodies, such as various PE bottle bodies and glass bottle bodies, especially for transparent BOPP and PET bottle bodies

2. Overall value

gcx materials have great challenges compared with other thin film materials in overall value

* the cost is lower than that of PE and BOPP, and it is competitive in price

* in terms of performance, it has the advantages of PE and BOPP at the same time, and can replace the two materials at the same time

* in appearance, two kinds of labels can be formed through glazing process; Fully transparent and matte fog label

* in terms of inventory management, reduce inventory reserve varieties and reduce the overall operating cost of the enterprise

* with good printing processing characteristics, customers can unify equipment and optimize management

gcx material is a new product launched by Allie company in the world at the same time. It has unified standardized management and technical services, and is a global brand. With the popularity of large household chemical companies in the world, gCx self-adhesive film material will be applied in China's label industry. Finally, I wish gCx materials to blossom and bear fruit in the Chinese market and contribute to the prosperity and development of the label industry