STENCIL FOR HOLE DRILLING Russian patent published in 2014 - IPC B26F1/16 H05K3/00 

FIELD: chemistry.

SUBSTANCE: layer of a water-soluble polymer composition, including a water-soluble polymer, a water-soluble lubricating material and 2,7-naphthalenedisulphonate-3-hydroxy-4-[(4-sulpho-1-naphthalene)azo]trisodium salt, is formed on the surface of a metal foil. A layer of the water-soluble polymer composition is obtained by cooling for 60 seconds from the initial cooling temperature, constituting from 120°C to 160°C, to the final cooling temperature, constituting from 25°C to 40°C, at the cooling rate, constituting not less than 1.5°C/s. A degree of crystallinity of the water-soluble polymer composition constitutes not less than 1.2, with the surface hardness of a layer of the water-soluble polymer composition constituting from 8.5 N/mm² to 20 N/mm² with the standard deviation of σ value of the surface hardness not higher than 2.

EFFECT: high accuracy of holes location.

8 cl, 4 dwg, 10 tbl, 29 ex