摘要 |
<p>This invention relates to the electrodeposition of tin-lead alloys; tin-lead alloy plating compositions; tin-lead alloy plating baths; and to processes for the electrodeposition of tin-lead alloys in the presence of: (a) at least 1 g./l. of at least one polyether of formula Q-(CH2CH2O)n-X wherein: n represents an integer of from 4 to 100; Q is chosen from the group consisting of: (i) an alkoxy group RO of from 4 to 18 carbon atoms; (ii) an alkyl phenoxy group of formula , wherin R' represents an aliphatic radical of from 8 to 20 carbon atoms; (iii) an amide group of formula R''CONH-, wherein R'' represents a branched or straight chain aliphatic group of 8 to 18 carbon atoms; and (iv) an amino group of formula , wherein R1 R2 and R3 each represent a straight or branched alkyl group of from 8 to 18 carbon atoms; and X is selected from the group consisting of hydrogen, SO3M and PO4M2, wherein M is hydrogen or a bath-compatiable cation comprising sodium, potassium, ammonium, magnesium, lead, tin, calcium, caesium, or rubidium; and(b) 0.1 g./l. to 1.0 g./l. of at least one aromatic aldehyde exhibiting at least one chloro substituent, or at least one compound producing an aromatic aldehyde exhibiting at least one chloro substituent; and, optionally, (c) from 0.25 to 5.0 g/l of at least one aliphatic amine, or a compound producing an aliphatic amine.</p> |