durable tampo pads, pad printer pad, pad printing rubber pad
· Excellent adhesion and detachment of the ink allowing a perfect transfer
of the image to be printed;
· Strength and resistance to solvents and inks for pad longevity;
· Hardness and form stability. Pad Print Machinery uses (Double-Aught / 00) on Shore Hardness Scale.
How to select and use pads:
Pad Selection
Selecting the right printing pad is crucial for image quality. Pad characteristics that affect imprint are: shape, size, hardness, surface finish, and material.
1. Shape
Shape is a most important factor: it is mostly the shape that determines how well the pad achieves its rolling action. HENGJIN’ advice:
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In general, the sharper the pad’s angle, the better the quality. However, if item to be printed onto has spherical surface (stress ball for instance), one should use flatter pads. Avoid pads with perfectly flat profiles, since these can trap air during ink pickup or deposition.
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Look for pad shapes that extend the profile to cover the entire image. Distortion of image edges in most cases is caused by undersized pads.
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Irregular ink pickup during the test print usually means that air is being trapped between pad and clichés’ surfaces. Watch carefully as the pad is imprinting to make sure that a rolling action is occurring.
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When possible, try to avoid using pad’s apex for ink deposit. This tends to thin the ink at that point and cause a light spot on the image.
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Always use as little pressure as possible to pick up and print the image: excessive pad pressure can cause distortion as well as poor ink transfer.
2. Size
In general, the larger the printing pad, the less image distortion. The pad should be at least 20-30% larger that the desired image size. So for the best quality use the largest pad size that is practical for the item to be printed onto. For larger items the maximum pad size will be dictated by printing machine’s parameters, namely by the distance between the image and machine’s body and its ability to compress large, hard pads.
3. Hardness
Hardness of the pad mostly depends on the amount of silicone oil that is used for pad molding. Pad hardness is measured by shore durometer tool; the same term refers to the measurement. “Shore 00” is a commonly used scale. The table below shows typical shore durometers that suit most of pad printing applications.
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Hardness
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Description
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35-40
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Soft
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50-
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Medium
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60-
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Medium hard
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70-
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Hard
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80-
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Very hard
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