FIELD: machine building.
SUBSTANCE: metal material has film formed at least on part of its surface containing at least poly-urethane polymer and silicon oxide. Also, poly-urethane polymer has one or more of siloxane bonds, a bond formed by dehydration condensation of a silanol group with another functional group, a silanol fragment and a urea fragment wherein sum of siloxane bonds, bonds formed by dehydration condensation of silanol groups with other functional groups, total amount of silanol fragments and silicon oxide are within ranges for solid particles of film expressed with the following equation, 1.6 wt % ≤((Wa+Wb+Wc+Wd)/W)×100≤25 wt %, where W is general weight of solid particles of film, Wa is weight of silicon forming siloxane group (-Si-O-Si-), Wb is weight of silicon forming bond created with dehydration condensation (-Si-O-R-), R is any element, other, than Si, Wc is weight of silicon forming silanol fragment (-Si-OH) and Wd is weight of silicon forming silicon oxide. Notably, ratio of general amount of urea fragments and urethane fragments to general amount of polymer components is within the range expressed with the following equation, 0.1 wt %≤((Ta+Tb)/T)×100≤10 wt %, where T is weight of polymer components in solid substances of film, Ta is weight of nitrogen forming urea fragment (-NH-CO-NH) and Tb is weight of nitrogen forming urethane fragment (-NH-CO-O-).
EFFECT: super corrosion resistance, adhesion to covering layer of paint, resistance to solvents and alkali, good processability and resistance to scratching.
20 cl, 3 tbl
