Presswork the fluidity of printing ink reachs his to determine method (2)

2, Touch denaturation

Have the aid of rotates viscosimeter scale D - when T curve, rise what make D with certain acceleration from 0 linear ground, in achieve rate of some the biggest shear (Dm) place makes fall, determine continuously the Y of meantime, have the material that touchs denaturation to the watch, namely, when making D rises, mix when dropping, d, the position of T curve is stagger, amid produces lag loop-line. Can think, the size of this loop-line represents the touchs denaturation bulk of this material.

Green falls in certain time-interval, pass section to the land increases or be reduced, put forward to evaluate the method that touchs denaturation by earning lag curve. The lag curve that gets according to this kind of method is roughly linear. Green thinks this represents the corporeal state that answers relatively with Dm of speed of the biggest shear point-blank, gets plasticity viscosity N_P1And succumb the change that was worth F to behave corporeal status.

Above all, change Dm of highest shear speed, beg as corresponding as this plasticity viscosity N_P1When, discovery is like the relation below;

N_P1=const, MlnDm (15)

The M in type is a kind of shows pattern of corporeal status change coefficient that is based on change of wind shear rate. To rotating cylinder viscosimeter, between the area A of lag loop-line and M, the scale that holds water as follows concerns:

A=(π H R₁²Dm²One R of ／ 4)(1₁²／ R₂²) (16)

Green discovers further, succumb value F has with N_P1The tendency that changes at the same time, give out to this next type:

F=const, V N_P1 (17)

V department shows its effect.

The apparent viscosity that touching metamorphic properties is the material when flow now is reduced, and lay going from place to place material when rising, apparent viscosity rises once more. Presswork printing ink once agitate, viscosity is reduced, place rise viscosity rises afresh again, this has been told in front. But, popularly says, the speed that makes viscosity is reduced because of flow, rise than placing restore unvarnished speed to want to be gotten greatly much. Accordingly, in should present those who restore effect to drop originally on the curve, show the change of viscosity scarcely. Printing ink is transferred in what move Mo Gun to go up, also undertaking flow and be placemented repeatedly, but because of placement time extremely short, the effect that restores so is not a problem into its.
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