Phenomenon of suitable wool produces a reason to reach in offset print answer sk
From;    Author:Stand originally

Presswork when on-the-spot, line or character, in the graph the brim of article can produce burr, this is the suitable wool that often says. Burr weighs wool to what bite buccal direction, burr says to arrange wool to what pull tip way. It is mixed in forme, mackintosh imprint taste the direction that go up to have consistency, it is the phenomenon that jam a store likely otherwise, also be double image phenomenon likely.

One, influencing factor

Following the ability when 3 elements exist at the same time can produce suitable hair: ① forme platen and line of rubber platen bag are incorrect, make the radius of the radius of forme platen and rubber platen unequal, and differ bigger. ② paper surface has more paper wool, opaque, sand to wait fall off to go up in mackintosh. Matrix of metal of material of ③ forme edition is not quite hard. Above 3 elements did not concern with embossing platen.

2, breakdown analysis and means of settlement

1, pour wool: Pour the generation of wool, below the case that has 3 afore-mentioned factors, imprint when R when > R oak, the linear velocity of forme surface is more than the linear velocity of mackintosh surface, close in pressing both generation sliding friction, the ink marks that makes go up with mackintosh on forme each other jam a store to opposite way. Because R imprints > R oak, the linear velocity of forme surface is fast, the ink marks of its surface spins to direction pulling an end; And the linear velocity of mackintosh surface is slow, the ink marks of its surface spins to direction gnawing a mouth.

The ink marks that spins on forme, the except the action collecting handwriting or painting of feeling fat action and Mo Gun eliminate that fights liquid medicine as a result of water roller, water. Although spin ink marks arises ceaselessly, but however by ceaseless eliminate. So the ink marks on forme spins is instantaneous, reason does not become the source that generates wool. And on mackintosh spin ink marks, cannot all move arrives on paper. As a result of the action sticking force of printing ink print, in print location accumulative paper falls off content is compared somewhere else much. These desquamation oily deposit becomes after content is the same as mix up of printing ink print. When producing sliding friction through forme and mackintosh embossing, it produces the way of active force down forme, slippage accumulation is on mackintosh. Because the oily deposit on mackintosh spins to print,direction adds much thickening ceaselessly, the plate arenaceous item that causes osculatory the place wears away destroy. Get again oily erode, feel gradually fat is lipophilic, produce burr phenomenon finally, and burr will be longer and longer. This is when generation pours wool, the reason that place of the burr on forme shines.

Handle way: Reduce forme gasket, smoke the gasket number that go to increase inside mackintosh, increase the center between rubber platen and embossing platen to be apart from appropriately at the same time. If the number filling up line of mackintosh accords with standard data, criterion forme is smoked go after gasket, want to narrow the center between forme platen and rubber platen is apart from.
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