3C Coatings

3C electronics like phones and laptop cases need high hardness and high gloss coatings. Winsir 3C Coatings use epoxy acrylate as the main resin. The cured film reaches 2H to 3H pencil hardness. It resists steel wool abrasion. We supply this 3C coatings resin to a coating factory in Dongguan. Their customer is a domestic phone brand. The housings coated with our EA-based UV topcoat passed sweat and abrasion tests. This product meets ISO 4624 adhesion standards. It is also suitable for bamboo flooring and metal decoration.

Winsir 3C Coatings use bisphenol A epoxy resin with an epoxy value of 0.51 to 0.53 eq/100g. This reacts with acrylic acid through ring-opening esterification. The reaction continues until the acid value drops below 3 mg KOH/g. The appearance is a pale yellow viscous liquid. At 25°C, the viscosity is 6,000 to 12,000 centipoise. Functionality is about 2. Density is 1.12 to 1.18 g/cm³. This 3C coatings resin is highly reactive. With photoinitiators like 184 or 1173, it cures fully under mercury lamps at 200 to 300 mJ/cm². To reduce viscosity for application, we recommend adding 20% to 40% reactive diluents like TMPTA or HDDA.

Winsir 3C Coatings deliver outstanding hardness. Formulated as a UV topcoat at 300 to 500 centipoise and tested to GB/T 6739, the pencil hardness is 2H to 3H. Steel wool abrasion testing (1kg load, 500 cycles) shows no scratches. It passes sweat and cosmetic resistance tests. For adhesion, cross-cut testing on PC plastic, ABS plastic, and aluminum (with primer) shows level 0 adhesion. No peeling occurs after tape pull. For gloss and fullness, the 60° gloss meter reads 95 GU or higher. The coating has good leveling and high distinctness of image (DOI), giving a mirror-like finish. Note that flexibility is lower with elongation at break below 5%. This 3C coatings resin is not suitable for soft substrates that need bending.