Patent ID: 7014721

Claim:
A Fe—Ni alloy material for a shadow mask having an excellent etching workability, wherein the alloy material comprises, in % by weight: Ni from 26 to 37 Si from 0.001 to 0.2 Mn from 0.01 to 0.6 Al from 0.0001 to 0.003 Mg not more than 0.001 Ca not more than 0.001, remainder Fe and inevitable impurities, the alloy material comprising at least two of the following inclusions (a) to (c) which are insoluble in an aqueous ferric chloride solution: (a) MnO—SiO 2 —Al 2 O 3 comprising, by weight, from 25% to 50% of MnO, from 40% to 60% of SiO 2 and from 5% to 30% of Al 2 O 3 , and wherein (CaO+MgO)≦30% by weight; (b) MgO—Al 2 O 3 spinel comprising, by weight, from 5% to 45% of MgO and from 55% to 95% of Al 2 O 3 ; (c) SiO 2 .