In the offset printing process due to the paper applied glue pore structure, smoothness, absorptive, viscoelasticity and other, paper filler in papermaking process, glue, pigment particles rough, poor quality of paper dust of appearance quality, spots, fibers, such as sand, often produce heap version of the fault. The main reasons are: the paper heap version of the hair removal, paper off powder, blanket paper wool, paper ash heap. Paper stack version of the reasons for different solutions are also different. 

, a paper version of the heap of hair removal 

Offset printing paper WOOL pile of version of the fault was mainly due to the paper surface fiber structure loose paper hair removal caused. This phenomenon is mainly the poor quality of printing paper, the fault surface imprinted ink surface for confetti like grey phenomenon, paper hair loss caused by a printing plate and blanket surface covered with paper wool, serious when printing every 1000 requires scrub the printing plate and rubber, causing the printing quality problem, delay the production schedule and delivery time. 

Paper positive and negative hair removal is papermaking raw material and pulp and paper in the process of technical problems, the offset is using indirect intermediate elastomer rubber roller printing, printing graphic transfer to the rubber roller, rubber drum in nano imprint lithography drum is transferred to the paper printing up a printing process, in an offset printing process paper wool will transfer from the surface of the rubber blanket to the printing plate, with the increase in the number of printing, stranded on the surface of the plate paper wool will accumulate, cause hair paper heap version of the fault, the paper wool will adhesion in printing graphics and text imprinted on the surface, thus affecting the printing quality. 

Paper fiber paper wool, paper ash is absorbent, and oil absorption, when printing graphics and text on adsorption paper wool, with the transfer of the plate cylinder, it first came across the water and moist, and water roller plates on a certain pressure, the paper wool after water and wetting and pressure, most stick tight in printing graphics and text on, followed by the ink roller. Then, after wetting the paper wool has oil resistance, although 4 root rollers on the ink and can't absorb ink, transfer to the blanket imprint will show grey phenomenon. 

Solution: 

(1) offset to master and ink balance, under the premise of cloth dirty version, reduce layout of water and reduce water roller pressure in the layout of the plate. The purpose is to make the surface of the plate paper hair wet to reduce as far as possible, in order to reduce the paper wool grease resistance and increase describes force, and try not to make it close to the layout. 

(2) increase the ink fluidity, viscosity, add a small amount of inking oil, use less ink printed products, and a corresponding increase in the rollers in a printing plate surface pressure, its purpose is paper in a printing plate on the hair after the ink roller, paper Mullah, transferred to the roller above, mainly in the string of ink roll accumulate. 

In addition, adjust the ink printability, add inking oil, auxiliary materials to repeatedly stir. Can also be appropriate to increase the amount of ink ink to solve the problem. 

, two paper shedding heap version: 

Surface of the paper off powder caused the heap version presents a honeycomb, sky full of stars, is countless filler, adhesive, pigment, auxiliary materials shedding caused by, seriously affect the quality of printing products, printing 1000 or so need to scrub a printing plate, the cause of formation and paper WOOL pile of version is similar, but the solution is different. The proportion of the paper wool and the powder is different, the gross area of the paper is light, and the powder is very thin. 

Solution: increase the ink liquidity, in printing ink in the appropriate add a thin inking oil, increased the viscosity of the ink and the ink transporting quantity, roller ink storage capacity increased to darken the imprinted ink. In addition, under the plate increase paper pad thickness to increase the printing pressure. 

Three, blanket on the stack of paper wool 

Also, paper made in grey paper oil paper process of reason in the printing process may appear paper shedding hair loss and accumulation in the blanket above, imprinted ink dot, graphic right transfer, the paper above the paper ash, paper powder will be through a rubber, printing plate cylinder, after channeling rollers, ink fountain inside the slot, thus affecting the monlchamus Road, transmission, meet the paper off powder serious paper and printing to the last fountain in full of gray paper wool, paper powder, then the amount of ink opened to the maximum, imprinted ink appear pale threadbare, printed on 1000 pieces of paper Baimang mang adhesion in the blanket, need to scrub blanket. 

Solution: 

(1) wash blanket. 

(2) before the official printing paper, printing a white oil and water, bridge the paper off powder - dropping the insufficiency (white oil is a white translucent emulsion and use it to weaken the ink, can reduce the ink viscosity, color uniform. Composed of magnesium carbonate, stearic acid, water, dry vegetable oil, mainly for the set of white oil rendering, reduce paper off powder, szlama. 

(3) in the printing ink to join a small amount of withdrawal adhesives, smooth of coated paper not to join, not too much, use no more than 3%. 

(4) increased 0.05mm thickness of the rubber drum pad of paper, or adjust the center distance to increase the printing pressure.