Usually mistaken as a sticker – A decal or transfer is a plastic, cloth paper or ceramic substrate that has printed on it a pattern that can be moved to another surface upon contact, usually with the aid of heat or water.
Different variations of decals: “water-slide” / “water-dip”; and vinyl “peel-and-stick”. A water-slide decal is screen-printed on a layer of water-soluble adhesive on a water-resistant paper, which must first be dipped in water prior to its application.
Upon contact with water, the glue is loosened and the decal can be removed from its backing; overly long exposure, however, dissolves the glue completely causing the decal to fail to adhere. A “peel-and-stick” decal is actually not a decal as described above, but a vinyl sticker with adhesive backing, that can be transferred by peeling off its base.
Decals are commonly used on hot rod automobiles, plastic models and stainless steel container. The advantages of a decal:
- Easily hand operated and Zero investment on equipment
- Logo vivid in colour and not easy to peel off after burning. Great for metal product since screen-printing is not suitable for those types of products.
- The decal’s cover coat is flexible and can be stretched to better fit the product – a good way to put logo on irregular shape of plastic or metal products
The disadvantages of decal:
- Potential defects if workers are not well trained or working under bad weather conditions.
- The logo positions are not precise – placements are hand made and therefore difficult to control. What is acceptable to a factory worker might not be acceptable to marketing people of a brand. Quality control is a must on all orders – all the more so with decals.
Here are the process points of water-slide or water-dip decal:
1. Immerse decal in clean water or 50 to 100 seconds, then remove and allow setting for at least one minute. Paper will lay flat and the decal will easily slide from the backing.
2. Slide the decal off the backing paper about 1/2″. Hold the decal with your fingertips (lightly) against the ceramic or product and slide the backing paper out from under the decal with the other hand.
3. Squeeze excess air and water bubbles from under the decal with the edge of a piece of cardboard or soft damp cloth, working from center of decal to the edges. Allow 2 hours or so to dry.
4. Fire with kiln well-ventilated until after smoking stops. Then close kiln and fire on a right temperature.
Cooling generally takes 3 to 6 hours before unloading the kiln, depending on the size and type of kiln and type of product being fired.