Polymeric binders having specific peel and cure properties and useful in making creped webs
This invention is directed to APE-free polymer binders formed by emulsion polymerization and having specific peel and cure properties. The APE-free polymeric binders have a peel value, when adhered to a heated metal surface, of 35% to 200% of the peel value shown by a standard APE-based polymer binder control (i.e., AIRFLEX® 105 vinyl acetate-ethylene polymer emulsion) and exhibit a cure profile such that at least 55% cure is achieved within 30 seconds at a temperature required for cure. Wet tensile strength is used as a measure of cure. The peel value is determined by a modified release and adhesion test. Binders having the peel and cure properties described herein can be considered for use in crepe processes, especially DRC processes.
1 . An alkylphenol ethoxylate-free polymer binder, said polymer binder formed by emulsion polymerization and having a peel value of 35% to 200% of a standard alkylphenol ethoxylate-based vinyl acetate-ethylene polymer emulsion control and a cure profile in which 55% cure is achieved within 30 seconds of being exposed to a temperature required for cure, said polymer binder effective as a binder in a crepe process; wherein the peel value is measured according to the following procedure:
(a) attaching a 2-inch×6-inch×{fraction (1/32)}-inch stainless steel plate to a movable heated (350° F.; 177° C.) inclined (45°) metal platform;
(b) allowing the stainless steel plate to equilibrate to the temperature of the platform (2 minutes;
(c) applying approximately 0.42 g of the alkylphenol ethoxylate-free polymer binder to a 1½-inch×6-inch piece of bleached, mercerized cotton poplin;
(d) attaching the jaws of a Testing Machine, Inc. gram tensile measuring apparatus to one of the long ends of the cotton poplin;
(e) pressing the coated side of the coated cotton poplin onto the heated stainless steel plate with a 3-pound lab roller by rolling the lab roller back and forth over the substrate for 10 seconds;
(f) after 30 seconds, moving the stainless steel plate away from the tensile measuring device (to which the cotton poplin is attached) at a rate of 12 inches/minute (30.48 cm/minute);
(g) recording the amount of force needed to remove the cotton from the stainless steel plate; and
(h) comparing the force in (g) to the force needed to remove cotton poplin using an AIRFLEX 105 VAE emulsion control.
2 . The polymer binder of claim 1 wherein said crepe process is a double recrepe process.
3 . The polymer binder of claim 2 wherein the peel value is 50 to 125% of control binder.
4 . An alkylphenol ethoxylate-free polymer binder, said polymer binder formed by emulsion polymerization and having a peel value of 35% to 200% of a standard alkylphenol ethoxylate-based vinyl acetate-ethylene polymer emulsion control and a cure profile in which 55% cure is achieved within 30 seconds of being exposed to a temperature required for cure, said polymer binder effective as a binder in a double recrepe process, wherein the peel value is measured according to the following procedure:
(a) attaching a 2-inch×6-inch×{fraction (1/32)}-inch stainless steel plate to a movable heated (350° F.; 177° C.) inclined (45°) metal platform;
(b) allowing the stainless steel plate to equilibrate to the temperature of the platform (2 minutes;
(c) applying approximately 0.42 g of the alkylphenol ethoxylate-free polymer binder to a 1½-inch×6-inch piece of bleached, mercerized cotton poplin;
(d) attaching the jaws of a Testing Machine, Inc. gram tensile measuring apparatus to one of the long ends of the cotton poplin;
(e) pressing the coated side of the coated cotton poplin onto the heated stainless steel plate with a 3-pound lab roller by rolling the lab roller back and forth over the substrate for 10 seconds;
(f) after 30 seconds, moving the stainless steel plate away from the tensile measuring device (to which the cotton poplin is attached) at a rate of 12 inches/minute (30.48 cm/minute);
(g) recording the amount of force needed to remove the cotton from the stainless steel plate; and
(h) comparing the force in (g) to the force needed to remove cotton poplin using an AIRFLEX 105 VAE emulsion control.