Drawn Cans

25 августа, 2015

Malyar

Internal lacquers for deep drawn or draw and redrawn (DRD) food cans are not based on acrylics resins, although the external basecoat may be for shallow drawn cans. Inks are distortion printed. The drawing process places high demands on the coating system. From a flat sheet, a can of up to five cm. in height may be drawn. In many cases the height of the can may exceed 5 cm. In addition to adhesion, flexibility and tooling resistance are required during the manufacture of the can, while resistance to the processing conditions is also necessary. Cooking food in the can demands steam and temperature resistance. If food leaks into the retorts, staining of the basecoat may occur. So stain resistance is also a necessary characteristic.

A starting point formulation for a drawn can basecoat may be:

FORMULATION 4-20: WHITE BASECOAT FOR SHEET FED DRAW APPLICATIONS

Rutile titanium dioxide	33.3
Flexible acrylamide acrylic
(50% in high BPt aromatic/butanol 4:1)	50.0
Epikote 1001 (75% solution)	3.7
Shellsol 150	8.6
Dowanol PM Acetate	4.4
Total	100.0