Overprinting
Please bear in mind that the ink film underneather is not chemically cured when first overprinted.If the ink film is dried at room temperature 20℃,overprinting must be carried out with hardener PUH in the course of 12 hours and with hardener PEMH in the course of 8 hours at the lates.We recommend to carry out the overprinting as soon as possible,in order to guarantee good adhesion between the ink layers.
Stress resistance
After proper and thorough drying(20℃-8days),the ink film exhibits outstanding adhesion as well as rub and scratch resistance and is resistant to most usual fillers(slightly alkaline to acid),as well as to alcohol,oils,greases,finger sweat,petrol,battery acid,and other solvents.In general,the chemical resistance of PU is improved by heat forced drying,e.g 150℃ for 30 min.If hardener HT1 is used,oven drying is essential.

Application:

Marapur PU is a versatile and highly resistant two-component ink which is applicable in all cases where highest demands for chemical and mechanical resistance for indoor and outdoor use have to be met.PU is also designed for printing onto polyolefines(PE,PP),the substrate's surface has to be pre-treated as usual by flaming or Corona-discharge.This increases the surface tension,and a sufficient adhesion can be achieved with a minimum surface tension of 42-48 mN/m.PU can also be processed with a spray gun,but preliminary trials are necessary for this process.We recomment to filter the thinned ink(25 μm screen)before processing,as otherwise there could be bubbles in the ink film.