The present invention refers to a paper surface sizing composition
comprising a copolymer having:
a) structural units derived from ethylenically unsaturated hydrocarbons;
structural units derived from monomers selected from esters of
ethylenically unsaturated mono-carboxylic acids, half-esters of
ethylenically unsaturated dicarboxylic acids, allylethers and vinylethers
and mixtures thereof; optionally
c) structural units derived from ethylenically unsaturated monomers
selected from monocarboxylic acids as well as salts and amides thereof,
dicarboxylic acids as well as salts, amides and half-amides thereof, and
cyclic anhydrides and imides of dicarboxylic acids and mixtures thereof;
and optionally
d) structural units derived from alkyl or amino-substituted alkyl acrylates
or methacrylates
with the proviso, that if no structural units c) are present, the
structural units b) are derived from monomers selected from half esters of
ethylenically unsaturated dicarboxylic acids.
A invenção atual consulta a uma composição de superfície de papel da cola que compreende um copolymer que tem: a) as unidades estruturais derivaram-se dos hidrocarbonetos ethylenically unsaturated; as unidades estruturais derivaram-se dos monomers selecionados dos esters de ácidos mono-carboxylic ethylenically unsaturated, metade-half-esters de ácidos dicarboxylic ethylenically unsaturated, allylethers e vinylethers e misturas disso; opcionalmente c) as unidades estruturais derivaram-se dos monomers ethylenically unsaturated selecionados dos ácidos monocarboxylic as.well.as sais e amidos disso, ácidos dicarboxylic as.well.as sais, amidos e metade-amidos disso, e anhydrides e imides cíclicos de ácidos e de misturas dicarboxylic disso; e opcionalmente d) as unidades estruturais derivaram-se do alkyl ou amino-substituíram-se acrylates alkyl ou os methacrylates com o proviso, aquele se nenhuma unidade estrutural c) estiver atual, as unidades estruturais b) são derivados dos monomers selecionados dos meios esters de ácidos dicarboxylic ethylenically unsaturated.
