First, the clean ink fountain small experience: the width of a wiper with a similar width on the transparent tape to clean up the ink, pull out the tape to throw away. When printing short-run jobs with an offset press, especially a small offset press, the ink fountain can be quickly and conveniently cleaned by this method.

Second, a method of printing on the ground

One has undertaken a number of spot color printing products in the field, using 80g/m2 coated paper. According to the conventional practice, we should print a PS printing on the field, but we used the old PS plate to print good quality, full field printing products without any flowers, which was well received by customers. The specific approach is to use an old PS version that is flat and smooth without any lens bumps and breakages. When printing, the reverse side of the plate faces the front, faces up, does not reach the water, and is only inked.

When printing coated paper, it is best to use quick-drying ink in order to prevent the back surface from being dirty. The 8% viscose is very effective for preventing stickiness. The addition of a tackifier to the ink not only prevents tackiness, but also does not affect the color saturation, and the ink layer appears brighter, clearer and more convenient for postpress processing such as calendering, laminating, bronzing, and the like.

Here, the viscose can replace dry oil and other anti-sticking dirty materials.

Third, plastic printing version, paste version troubleshooting

Flower version and paste version are one of the most common failures of offset printing. Finding and resolving problems in a timely manner is an inevitable way to improve the quality of printed products and reduce the scrap rate. The following is a summary of the common causes of pattern and paste, and the corresponding solutions are provided for your reference.

Flower version

(1) The water supply is too large;

This can be solved by reducing the bucket roll angle or reducing the bucket roll speed.

(2) Too much water in water glue

The water roller is operated in a state of suspending the upper water to consume excessive moisture absorbed by the water sac, or to scrape excess moisture in the water sizing with a squeegee.

(3) Ink emulsification serious

Replaceable ink try.

(4) Excessive pressure between the water roller and the plate

Reduce the pressure of the water roller.

(5) The pressure between the ink roller and the plate is too small

Increase the pressure on the ink roller.

(6) Long printing time

Problems from the plate must be completely resolved by replacing the plate.

2. paste version

(1) Insufficient water

You can increase the amount of water by increasing the angle of the fountain roller or increasing the speed.

(2) There is less water in the bucket, resulting in insufficient water supply

This type of failure is most likely to occur when water is added manually. The solution is: add water to the bucket to ensure adequate water supply.

(3) The water roller or the water roller is seriously worn out, resulting in a poor appearance of Sheung Shui.

(4) Adhesion of ink and other oily impurities to the surface of the fountain roller due to the repulsion of the ink

Scrub the bucket roller.

(5) There are too many inks on the surface of the water velvet or string water roller, causing the water to pass. After the water velvet or water roller is cleaned, the problem will be solved.

(6) The pressure between the water rollers or the pressure between the water roller and the plate is insufficient to try to adjust the pressure.

(7) The pressure between the ink roller and the printing plate is adjusted excessively.

(8) Too much ink needs to reduce the ink supply.

(9) When the ink roller is closed too early, it should be filled with water and ink.

(10) Exposure of the surface of the plate, resulting in poor hydrophilicity, must be replaced.

In addition to the printing version and the paste version, the printing ink and the paste version are related to the printed version. In the final analysis, the ink and wash ink is not balanced. Practice has proved that: The best state of offset ink and ink balance is to use as little water as possible on the basis of not dirty, except for waterless offset printing. Only by properly understanding the ink-and-wash balance can you print a good product.

Fourth, CPC has a large amount of ink, but the actual amount of ink is relatively small

1. Cause of failure: The ink fountain film is used for a long time. The ink that has leaked is agglomerated under the ink fountain film, causing the ink volume to drop.

Remedy: Clean the ink on the column eccentric (a total of 32) and replace the dirty sponge strip with a new one (the life of the ink film is 36 hours).

2, the cause of the malfunction: the amount of ink on the motor thread to control the amount of ink, so that the thread rotation is insufficient or even stuck, causing no ink or ink out of uniform.

Remedy: Disassemble the 32 baffles under the ink fountain (note: do not lose the hollow sleeve on the fastening thread), remove the ink on the thread with the needle, and remove all the ink from the clean ink, move the CPC to make each motor It can flexibly run from the lowest ink volume to the highest ink volume, and fill the tank with full butter to keep the ink effect for a long time. The use effect is very good.

Fifth, the causes of blanket aging and ways to overcome

The cause of the aging of the blanket

1. In the daily production of the blanket, due to prolonged contact with the fountain solution, ink, gasoline, and kerosene, the elasticity will decrease, and the surface will age and glow.

2. It is fixed for a long time and tightened on the drum. After being rolled by the drum, the blanket is stiff and loses its balance and high elasticity.

3. The influence of external environmental conditions, such as the effects of air, light, and heat, destroys the chemical structure of the blanket and changes its physical properties. Its mechanical properties are degraded, hardened, brittle, and cracks or hair may occur when severe. Soft sticky.

How to Prevent Blanket Aging

1. Each time when the machine is shut down for a long time, the ink of the blanket should be washed away and dried to leave no residue, to prevent the surface rubber from being too smooth and hardened and to improve the aging. When there is a lot of paper wool, silt and fillers and other impurities accumulated on the surface of the cloth, it is necessary to insist on washing the blanket, keep the surface of the rubber cloth clean, prevent the impurities from being accumulated too thick, harden into a solid, and press the blanket to make Partial loss of elasticity of rubber.

2. After washing the blanket, take some talcum powder on the blanket to restore the elasticity of the blanket.

3. When the printer is not printing for a long time, the blanket should be relaxed to restore its original elasticity. Replace the blanket, should be cleaned, take some talcum powder, and wrapped in opaque paper in a cool place.

4. Use organic solvents with fast evaporation and strong solubility as the detergent for blankets. Light oil is commonly used as a detergent in our factory, while slow evaporation of kerosene can make the blanket swell. In addition, when printing, it is necessary to pay attention to the printing pressure. The overprinted paper should be kept well. It should not contain sand and other sundries. Do not use paper with folds, adhesions or incompleteness. At the same time, blankets should be kept away from high temperatures or low temperatures, away from electromagnetic, intense light, and chemicals.