Offset printing operation;
sometimes encounter the phenomenon of wrinkled paper. So why is there such a
phenomenon? See below for an analysis of:
First, offset
printing paper wrinkles, wrinkled variety of reasons
1. Pressure
feeding station pinch rollers uneven
As the role of
paper in the transfer process by axial forces, cause the paper to be designated
musters positioning the front middle part, in the nip forming folds.
2. The impression
cylinder ranging gripper force
If the impression
cylinder gripper on both sides of the force is insufficient, wrinkled paper at
the drag shoot; If one side of the force is insufficient, then the
corresponding drag tip edge wrinkling; If the middle of the force is
insufficient, then the middle part of the paper to wrinkle.
3. Paper improper
transfer
In the paper transfer
process before printing, if mismatch, resulting in its gripper edge paper
length is changed, the drag shoot parts wrinkle easily.
4. The dental pad
spiky
When the paper is
grabs, if dental pad uneven, the paper will wavy edge, gripper parts of the
local wrinkling.
5. The position
paper edge and gripper inaccurate
After positioning
the paper, if the paper is grabs a little, resulting in an uneven edge of the
paper to produce wrinkle.
6. The impression
cylinder surface adhesion of the ink is too thick
Impression
cylinder surface adhesion of the ink is too thick when the paper embossed
uneven service, will produce local short interval wrinkle deformation.
Paper Reason
1. Knock paper
traces too deep, too close
Because of
improper paper hard knock, knock on the paper to make signs too deep, too
close, and knocking at the crease the paper when printing is easy to produce
wrinkles.
2. Paper silk
thread direction
Embossing the
paper into the machine, if you are straight silk thread, silk head so easily
cause wrinkling.
3. Paper excessive
moisture
Paper excessive is
moisture, the paper's own fiber expansion in the imprinting process, the
expansion of the fiber by mast narrowing, easy to produce gripper tip toward
the direction of dendrite drag folds.
4. Effects of
temperature and humidity
Environmental
temperature and humidity changes will be resulting in uneven water content of
paper, such as water content greater than around the middle, resulting in lotus
leaf, printing paper wrinkle easily.
Second, offset
printing paper wrinkled effective solution
After wrinkled
paper fault thrown, there must be targeted to take measures, thereby ensuring
the efficiency and quality of the printing. For wrinkles caused by the above
reasons, we can take the following measures to overcome them.
First, the sheet
appropriately knocks process, in order to improve the printability of paper, to
achieve the elimination the next color printing wrinkling purposes.
Second, adjust the
gripper drum to average strength, so place the sheet in the gripper,
eliminating wrinkling failure due to disorders caused by the transfer paper.
Third, when the
imprint, to ensure paper calm and close to the impression cylinder.
In addition to the
mechanical aspects of the causes and reasons for the paper itself, the package
lining improper use can cause the paper to wrinkle. Such as packing too soft,
convex hull, the actual situation of the case, or lining is not tight, the
paper will cause wrinkling. Therefore, we should also pay attention to the
packing process, to prevent wrinkling due to loose caused false lining.
China Printing Export Co. Ltd.
has a high-end printing equipment and professional printing staff. Producing
high-quality printed products. It is strength of the china printing company. Company
has advanced printing equipment and an excellent team composed of 50
professionals as well as more than 150 skilled workers. It has passed ISO9001
and ISO14001 certifications. It is a professional manufacturer of various
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