Paper sized with a sizing agent and a selected sizing promoter
View Patent ↗Sized paper containing an amphoteric promoter resin that is a polymerization reaction product of a quaternary diallylammonium monomer, optionally a diallylammonium monomer, and an unsaturated organic acid is described. The method of sizing paper with such amphoteric promoter resin compound and a sizing agent provides sized paper with significantly improved sizing property characteristics, and the sized paper exhibits superior retention of brightness due to added optical brighteners.
1. A method of producing sized paper in a paper making machine in which a paper pulp is entered into the wet end of the machine which comprises adding to the pulp, 1) an optical brightener, 2) sizing agent and 3) a water soluble amphoteric promoter resin that is
(a) a polymerization reaction product of a monomer comprising at least one polymerizable cationic amine monomer of formula (I)
where G is a selected from alkyl, alkenyl, allyl, aryl; heteroatom interrupted alkyl or alkenyl, wherein the heteroatoms are selected from the group N, S, and O; and J, K, and L are selected from hydrogen, alkyl akenyl, allyl, styrenyl, and aryl; heteroatom interrupted alkyl or alkenyl, wherein the heteroatoms are selected from the group N, S, and O; and X is a sizing compatible anion; and
(b) at least one polymerizable organic acid of formula (II)
where R x , R y , and R z , are hydrogen, alkyl, alkenyl, aryl heteroatom interrupted alkyl or alkenyl, wherein the heteroatoms are selected from the group N, S, and O; and E is an organic substituent selected from the group COO, SO3, HSO4, and H2PO4; and wherein the mole percent of the cationic amine units of formula I constitutes at least 25% of monomers in the amphoteric promoter resin and the mole percent of the organic acid of formula II constitutes at least 25% of monomers in the amphoteric promoter resin, wherein the additives 1), 2), and 3), become distributed throughout the interior of the resulting paper.
2. The method of claim 1 wherein the E in the monomer of formula II is COO.
3. A method of producing sized paper in a paper making machine in which a paper pulp is entered into the wet end of the machine which comprises adding to the pulp 1) a sizing agent, 2) an optical brightener and 3) a water soluble amphoteric promoter resin that is
(a) a polymerization reaction product of monomer comprising at least one cationic quatemary diallyl ammonium monomer of formula (III).
optionally, including at least 1 cationic diallylammonium monomer of formula (IV)
where R 1A , R 1B , R 1C and R 1D are hydrogen or C 1 -C 22 straight chain or branched alkyl; R 2 and R 3 are alkyl, alkenyl, aryl, heteroatom interrupted alkyl or alkenyl,
wherein the heteroatoms are selected from the group N, S, and O; R 4 is hydrogen, alkyl, alkenyl, aryl, heteroatom interrupted alkyl or alkenyl, wherein the heteroatoms are selected from the group N, S, and O; and X— is a sizing compatible anion and
(b) at least one organic acid of formula (II)
where R x , R y , and R z , are hydrogen, alkyl, alkenyl, aryl, heteroatome interrupted alkyl or alkenyl, wherein the heteroatoms are selected from the group N S and O and E is an organic substituent selected from the group N, S, and O and E is an organic substituent selected from the group COO, SO3, HSO4, and H2PO4; and wherein the sum of the mole percent of the cationic quatemary diallyl ammonium monomers of formula (III) and the mole percent of the diallyl ammonium monomers of formula (IV) constitutes at least 25% of monomers in the amphoteric promoter resin and the mole percent of the unsaturated organic acid of formula (II) constitutes at least 25% of monomers in the amphoteric promoter resin wherein the additives 1), 2), and 3), become distributed throughout the interior of the resulting paper.