Common materials used for anti-counterfeiting scratch cards include coated paper (specifications such as 157g, 200g, 250g, etc.), white cardboard, self-adhesive paper, and PVC. The most commonly used are 250g coated paper and self-adhesive paper. Coated paper has a glossy surface suitable for double-sided printing, while white cardboard is glossy on the front but only suitable for printing simple content on the back. PVC is less commonly used due to its higher cost.

 

Coating materials and usage methods for scratch cards

Ink colors: silver, silver-gray, green, black. Ink removal: Scratch card ink can be easily scraped off with a hard object or fingernail. Usage instructions: It can be printed using the offset lithography method, but opaque substrates should be selected to enhance security. Water-absorbent substrates should be avoided. Applying UV varnish on the substrate surface before using scratch card ink can improve the scraping effect. If printed on high-quality coated paper, ideal results can also be achieved. Base layer printing: When printing patterns or numbers such as lottery tickets using the offset lithography method, excessive use of spray powder may cause a raised effect. If the scratch card ink cannot completely cover the winning pattern or number after overprinting, the spray powder should be wiped off with a cloth before printing or avoided altogether. Before printing scratch card ink, the offset ink layer must be completely hardened; otherwise, it may be softened by the solvent of the scratch card ink, leading to leakage of the lottery pattern or password. The base layer (pattern or winning number) must be completely dry before applying the coating. Screen printing materials: If the scratch card ink has a certain thickness, the ink layer can be easily scraped off. Screen printing scratch card ink is best printed using a 150-200 mesh screen. Both polyurethane and rubber squeegees can be used. Dilution: Generally, no dilution is needed; if necessary, no more than 8% diluent can be used. Slow-drying agents are generally not required. Coverage: Maximum coverage can reach 36 square meters per kilogram. Drying time: Scratch card ink is fast-drying. Normal ink layer thickness dries in about 20 seconds. Main components: 1. Resin, oil-friendly; 2. Pigment, mainly aluminum material with titanium white and gray, and a small amount of calcium carbonate; 3. A small amount of additives. Scratch card ink has the following characteristics: 1. High covering power, providing excellent confidentiality; 2. Good wear resistance; 3. Easy to scrape off; 4. The ink automatically curls when scraped, making it less likely to fall off as powder and more environmentally friendly; 5. The difficulty of scraping does not increase with storage time after printing; 6. Hot air drying. Printing method: Scratch card ink is only suitable for screen printing.