What is the matter that plastic packaging bags will be red after being printed for a long time

It should be that the ink quality is not up to standard.

Everyone knows that inks are chemicals. Chemical changes are related to temperature, humidity, catalysts, etc. If the room temperature and humidity of the printing part on the surface of the gift box are not suitable, especially under the light catalysis, because the light source of sunlight and light is yellow, and a layer of yellow is covered on the surface over time.

It looks yellow and old, and the blue me turns blue-green.

1. Is it fast or slow? Sticky? Unclear expression.

2. What is the material of the plastic suitable for printing, and the appropriate printing method should be matched with the correct ink and thinner.

3. There is also a certain proportion of ink and thinner.

4. There is also a certain relationship between printing work and weather, and the weather will affect the thinner.

There may be two reasons why the printing of opp packaging bags will fade, one is that the raw materials are not over-powered or the electricity is not enough; The second is that the ink used for printing may not be very good.

Printing: Printing, graphic arts, graphic communications is a technology that transfers the ink to the surface of paper, fabrics, leather and other materials through the processes of plate making, ink application, pressurization and other processes, and copies the content of the original manuscript in batches. In a simple sense, printing is a process technology that uses a printing plate or other means to transfer the information on the original to the substrate, and can also be understood as the reproduction process of transferring the colorant pigment (such as ink) to the substrate using an analog or digital image carrier.

OPP packaging is generally used in food packaging, and the fading of the packaging leads to excessive content of harmful solvents and heavy metals and other substances carried by the packaging contents, which affects the health of consumers. Colour fading will also lead to the loss of the content of the specific information of the product on the surface of the packaging, which will bring inconvenience to the sales of food.

The reasons for the decolorization of the ink layer caused by the quality problems of the packaging are mainly concentrated in the following points:

1) The content resistance of packaging materials is poor - such as oil resistance, acid and alkali resistance is poor, when the packaging materials are used to package such food, the ink layer is easy to migrate into the food, and the ink layer falls off and contaminates the food.

2) The fastness to the combination of packaging materials and ink is not enough - such as poor compatibility between ink and printing materials, and the surface properties of printing materials do not meet the printing requirements, etc., the ink layer is prone to fall off.

UCBAN can provide complete and professional solutions for food enterprises, starting from the quality of incoming packaging materials, effectively identifying leading suppliers for enterprises, and guiding the improvement of packaging processes, so as to avoid the problem of ink layer decolorization caused by unqualified packaging quality.

Hello, is it fading during printing, pulling ink, or fading after compounding, will it be your printing electrostatic treatment surface is wrong, or is it a problem of the time to enter the oven, note that if the printed matter is left for a long time, there will be the possibility of oxidation.

The ink used is wrong, and the same material should be used with the same ink, so that it will not fall.

Do you use domestic ink or imported ink? We've also printed it, and if we don't pick it hard, it won't fall off.

This kind of printing first picks up the table of the material to check whether the ink is good, and uses (Daying pen) to test.

Plastic printing is divided into colors, can only print the ground, suppose you print purple, then an ink roller can only run purple ground. Print gray, then you can only run gray ground. There is no screen printing, and the number of filaments refers to the thickness of the plastic bag.

It is not a few colors, but a few colors, and there are several thick and thin specifications of plastic bags according to C.

Is your company **? Let me tell you this.

First, a few colors, that is, a few colors with several plate rollers, a color is required a plate roller, the more colors you have, the higher the cost of plate making. Of course, plate making is calculated by area, and the larger your area, the higher the cost of plate making.

Second, a few threads of thickness, a trace is, the thicker the material, the higher it must be, so in the case of ensuring the strength of your plastic bag, it is more cost-effective to use a thinner one.

Third, depending on what materials you use, PE PP PET, etc., the materials are not the same, this is generally the printing house to help you determine what materials to use.

Printing is not working now! Not before! Nothing has done it! I want to change careers.

I happen to be doing plastic printing.

For your question:

Colors are based on the actual quantity. CMYK even 4 colors, white, other spot colors (such as M+Y red, paper can be superimposed, plastic printing here is a spot color, plastic printing generally does not superimpose.) Other colors and so on).

Simply remember: all physical items are 5 colors (black, blue, magenta, yellow, white) plus other spot colors.

Because it is gravure printing, it is considered a lot of plates if there are many colors.

**According to the size of the plate, it is currently an ordinary (non-gradient) yuan square centimeter, and a gradient color (line version) yuan square centimeter.

Supplementary questions for you:

Of course, the paper can be superimposed with 4 colors, or it can be a spot color!

Plastic printing is definitely a spot color. Just one edition. The royalty is also cheap.

That's right, if there is only one color, the plastic bag must be overprinted in a spot color, not like the carton, because plastic overprinting is more difficult and will increase the cost.

Right! But CMYK and spot colors are the same**.