Paper making process using binder/filler agglomerates
View Patent ↗A process for making paper, comprising contacting an anionic binder with a cationizing agent to make a cationized binder, contacting the cationized binder with an anionic pigment to form a binder/pigment agglomerate, contacting the agglomerate with an aqueous slurry of fibers, and forming a paper product from the slurry. The agglomerate may reduce the total cost of the paper product being produced while maintaining the strength of the paper at acceptable levels.
1. A process comprising
contacting an anionic binder comprising a synthetic latex with a cationizing agent under conditions sufficient to convert the anionic binder to a cationized binder, wherein the contacting of the anionic binder comprising the synthetic latex with the cationizing agent occurs in the absence of anionic pigments, further wherein the cationizing agent is a polyamidoamine-epihalohydrin polymer,
then contacting, in the substantial absence of fiber, the cationized binder with an anionic pigment to form a binder/pigment agglomerate,
contacting the agglomerate with an aqueous slurry of fibers, and
forming a paper product from the slurry.
2. The process of claim 1 wherein the cationizing agent has cross-linking functionality.
3. The process of claim 1 wherein the dry weight ratio of cationizing agent to binder is from less than about 1:1 to about 1:3.
4. The process of claim 1 wherein at least two different cationizing agents are used.
5. The process of claim 1 wherein the cationizing agent is a polyamidoamine-epichlorohydrin polymer.
6. The process of claim 1 wherein the paper product is printing paper or writing paper.
7. A process comprising
contacting an anionic latex with a polyamidoamine-epichlorohydrin polymer under conditions sufficient to convert the anionic latex to a cationized latex,
then contacting, in the substantial absence of fiber, the cationized latex with an anionic pigment to form a latex/pigment agglomerate,
contacting the agglomerate, and optionally a retention aid, with an aqueous slurry of fibers and
forming a paper product from the slurry.
8. A paper product prepared via the process of claim 1 .
9. The process of claim 1 , further comprising contacting a retention aid and/or other additives with the aqueous slurry of fibers.
10. The process of claim 1 wherein between about 2 and about 20 dry weight parts of the anionic binder are employed per 100 dry weight parts of the anionic pigment.
11. The process of claim 1 wherein the dry weight percent of the binder/pigment agglomerate in the paper product is from about 5 to about 70.
12. The process of claim 1 , further comprising adjusting a pH of the cationizing agent to at least about 8 prior to contacting the anionic binder with the cationizing agent.
13. The process of claim 1 , further comprising adjusting a pH of the contacted anionic binder and cationizing agent to less than about 5 to convert the anionic binder to the cationized binder.
14. The process of claim 1 , wherein contacting the cationized binder with the anionic pigment comprises adding the cationized binder to a slurry comprising the anionic pigment.
15. The process of claim 1 , wherein the anionic binder comprises from about 10 weight percent to about 20 weight percent solids content during contacting with the cationizing agent.