Self-adhesive label materials are divided into two types: paper self-adhesive labels and film self-adhesive labels according to the surface materials. With the acceleration of industrialization and the enhancement of people's awareness of environmental protection, film self-adhesive materials have risen. The choice of film surface materials is related to many factors such as the application environment, adhesives, substrate characteristics, etc.

The in-mold label materials are divided into four types according to the material characteristics: BOPP, PP+PE, PE, and paper. Due to the different processing characteristics of materials, the application effect is also different.

1. BOPP: Biaxially stretched, with special coating on the surface, good printability. The disadvantage is that it is easy to deform on a large area of ​​the container. If the material of the barrel is PE and the label material in the mold is PP, because the shrinkage ratio of the two is different, the orange peel phenomenon will appear on the surface of the barrel after the application of the label.

2. PE: Without stretching, corona treatment is required on the surface of the material, poor printing adaptability, and large deformation after hot stamping. Since it is a PE material, no deformation occurs after being applied to a PE bottle body.

3. PP+PE: Uniaxial tensile deformation, corona treatment on the surface of the material, good printability, and stable tension. Since the material contains a PE component, a low-temperature hot stamping foil is required in the label hot stamping process. The biggest advantage is that the label has a smooth surface, no distortion, and good visual effect after application.

4. Paper: Applied to low-grade packaging products, suitable for non-deformation or small deformation of the barrel. The commonly used materials are high-grade coated papers, and the printability of paper materials is better.

In-mold label material has two appearances depending on the application range

1. Smooth surface material: Suitable for curved bottle shape, because the curved bottle body can naturally exhaust when contacting with the label during the blowing process, without bubbles or wrinkles.

2. Rough surface material: It is a regular pattern that is manually printed or rolled out and is suitable for a flat bottle body. When the flat bottle body is in contact with the label during the blowing process, the air can be naturally exhausted through the small pattern that passes through, and bubbles and wrinkles do not occur.

Japan YUPO Synthetic Paper

(1) Characteristics of YUPO Synthetic Paper In-mold Labels

A. Polypropylene PP is a raw material, and is made of biaxially-stretched inorganic fillers. It has the characteristics of paper and plastic films. Compared with ordinary paper, it is more resistant to acids, alkalis, water, oil, mold, and friction.

B. Fully adhering to the container, even if the edge of the special shape paper is not raised, it is not easy to fall off.

C. No coating process, no problem of coating stripping, easy exhaust stripe on the back layer, short molding time and high efficiency.

D. Excellent weather resistance, no discoloration or cracking in the harsh outdoor environment such as ultraviolet rays, use or preservation for a long time.

E. The smoothness, flatness, and thickness of the surface height are excellent with the adhesive.

F. With a smooth surface and high whiteness, it faithfully reflects the printing effect. Suitable for web offset and flexo printing.

G. Has different grades of self-adhesive products that can be used for permanent adhesives, removability adhesives.

H. For offset printing, small and medium-sized batch label products, if the bulk printing recommended gravure; if the ink requires high recommended UV printing.

(2) Use of YUPO Synthetic Paper In-mold Labels

A. Use of life products

● Food use: frozen food label (ice-cream box)

● Medical use for life: shampoo, hair conditioner label, medicine label

● Use of clothing: Advertising labels, size labels

B. Industrial use

● Car use: battery label, wire label, tire label

● Use of electronic home appliances: description labels, warning labels

● Container labels: iron drum labels, chemical container labels, oil barrel labels

(3) Printing of YUPO "IML"

A. YUPO "IML" In-mold labels are generally offset, flexo, and gravure. Japan mostly uses UV offset printing, UV rotary printing and gravure printing; China mainly adopts ordinary offset printing, flexo printing, and gravure printing, and then prints and polishes.

B. It is recommended to keep the humidity between 50% and 60%, or use a static eliminator to remove static electricity.

C. When printing YUPO in-mold labels, they must be last glazed, and the surface varnish can improve the smoothness so that the labels do not stick to each other.

Avery Dennison Film Labels

The patented film products Primax, FasClear, are transparent and white polyolefin multi-layer composite mold inner label films, functionally divided into print layer, core layer and adhesive layer. The printing layer surface can provide excellent printability, the core layer determines the stiffness and transparency of the label, and the adhesive layer ensures excellent composite properties between the label and the bottle body.

(1) Characteristics of Avery Film Labels

A. The label and bottle body are on the same surface, and the color pattern is printed directly on the surface of the bottle body.

B. Film materials, especially Primax, FasClear, can be used for stretching and shrinkage. It can be used on plastic bottles to deform with the deformation of the bottle without wrinkling.

C. The surface of the film material does not absorb ink. The printed label has a bright color and a strong three-dimensional effect. The color effect is better than paper.

D. The in-mold label of the film has good environmental protection, and the label and bottle body can be melted at the same time and suitable for recycling.

E. Corona treatment is suitable for printing, suitable for various printing processes, and is suitable for labels on cosmetics and cosmetic products.

(2) Manufacturing Processes for Primax and FasClear from Avery Film Materials

A. The plastic pellets of BOPP and PE were placed in an extruder and melted and squeezed separately into a casting device.

B. The solution was mixed in a casting device and the mixed solution was passed through the gap of the casting device by compressed air.

C. Cool and thin the film with a chill roll.

D. After the machine direction of the film is elongated by the orientation drawing device, the film is formed into a longitudinally deformable film.

E. Increase the surface tension of the film by the corona device.

F. Rolled into a printable or coated film material. Matte, pearlescent, plain synthetic paper

(1) Features of matte, pearlescent, plain synthetic paper

A. The matte label surface has a matt effect, and the matte texture has a non-slip effect, which effectively prevents the bottle body from slipping; the plain label is an ordinary paper effect; the pearlescent label surface has a natural pearl color and has a strong anti-counterfeiting function.

B. Use universal offset printing, gravure printing, flexo printing, etc. for surface printing. Only need to be coated with glazing oil after printing to achieve a certain degree of solidity, eliminating the need for the coating process after the printing of traditional polymer substrates and reducing The label production cost.

C. The advantage lies in the superior surface performance, which is more suitable for offset printing. It has a wide range of products, a variety of products, and is made in China with high cost performance.

D. Inadequacies are poor stiffness, which is limited by the application of high-end products.

(2) Main application of products

A. Washing, cosmetics. Such as: shampoo, hair conditioner, bath liquid, washing liquid, kitchen cleaning agent and so on.

B. Trademarks and instructions for large-capacity blow barrels and injection containers for chemical raw materials, pesticides, paints, and lubricants.

C. Labels and instructions for food containers such as salad oil, ice cream, condiments, soy sauce, vinegar, and other plastic buckets, bottles, and boxes.