Spunlaid Fibers Comprising Coated Calcium Carbonate, Processes For Their Production, and Nonwoven Products

Abstract

Disclosed herein, in one embodiment, are spunlaid fibers comprising at least one polymeric resin and at least one filler having an average particle size of less than or equal to about 5 microns and/or having a top cut of less than about 15 microns, wherein the at least one filler is present in an amount of less than about 40% by weight, relative to the total weight of the spunlaid fibers. Also disclosed herein is a method for producing spunlaid fibers comprising adding calcium carbonate to at least one polymeric resin and extruding the resulting mixture. Further disclosed herein are nonwoven fabrics comprising such spunlaid fibers and methods for producing them.

1 . A spunlaid fiber comprising at least one polymeric resin and at least one coated filler having an average particle size of less than or equal to about 3 microns, wherein the at least one coated filler is coated calcium carbonate and is present in the fiber in an amount less than about 40 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         2 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate is present in an amount less than about 25 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         3 . The spunlaid fiber of  claim 2 , wherein the calcium carbonate is present in an amount less than about 15 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         4 . The spunlaid fiber of  claim 3 , wherein the calcium carbonate is present in an amount less than about 10 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         5 . The spunlaid fiber of  claim 1 , wherein the coating of the calcium carbonate is at least one organic material chosen from fatty acids and salts and esters thereof. 
     
     
         6 . The spunlaid fiber of  claim 5 , wherein the at least one organic material is chosen from stearic acid, stearate, ammonium stearate, and calcium stearate. 
     
     
         7 . The spunlaid fiber of  claim 1 , wherein the at least one polymeric resin is chosen from thermoplastic polymers. 
     
     
         8 . The spunlaid fiber of  claim 7 , wherein the thermoplastic polymers are chosen from at least one of polyolefins, polyamides, polyesters, copolymers thereof, and blends thereof. 
     
     
         9 . The spunlaid fiber of  claim 8 , wherein the polyolefins are chosen from polypropylene and polyethylene homopolymers and copolymers. 
     
     
         10 . The spunlaid fiber of  claim 8 , wherein the polyamide is nylon. 
     
     
         11 . The spunlaid fiber of  claim 1 , wherein the at least one polymeric resin has a melt flow rate ranging from about 20 to about 40 g/10 min. 
     
     
         12 . The spunlaid fiber of  claim 1 , further comprising at least one additive chosen from mineral fillers, inorganic compounds, waxes, optical brighteners, heat stabilizers, antioxidants, anti-static agents, anti-blocking agents, dyestuffs, pigments, luster improving agents, surfactants, natural oils, and synthetic oils. 
     
     
         13 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has an average particle size of less than or equal to about 2 microns. 
     
     
         14 . The spunlaid fiber of  claim 13 , wherein the calcium carbonate has an average particle size of less than or equal to about 1.5 microns. 
     
     
         15 . The spunlaid fiber of  claim 14 , wherein the calcium carbonate has an average particle size of less than or equal to about 1 microns. 
     
     
         16 . The spunlaid fiber of  claim 15 , wherein the calcium carbonate has an average particle size of less than or equal to about 0.5 micron. 
     
     
         17 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has an average particle size of less than or equal to about 100% of the average diameter of the spunlaid fibers. 
     
     
         18 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 3 microns. 
     
     
         19 . The spunlaid fiber of  claim 18 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 2.5 microns. 
     
     
         20 . The spunlaid fiber of  claim 19 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 2 microns. 
     
     
         21 . The spunlaid fiber of  claim 20 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 1.5 microns. 
     
     
         22 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         23 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has an average particle size of about 1.5 microns. 
     
     
         24 . A nonwoven fabric comprising at least one spunlaid fiber of  claim 1 . 
     
     
         25 . The spunlaid fiber of  claim 1 , wherein the calcium carbonate has a top cut of about 15 microns or less. 
     
     
         26 . The spunlaid fiber of  claim 25 , wherein the calcium carbonate has a top cut of about 10 microns. 
     
     
         27 . The spunlaid fiber of  claim 26 , wherein the calcium carbonate has a top cut of about 6 microns. 
     
     
         28 . The spunlaid fiber of  claim 25 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         29 . The spunlaid fiber of  claim 28 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 10 microns. 
     
     
         30 . The spunlaid fiber of  claim 29 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 6 microns. 
     
     
         31 . The spunlaid fiber of  claim 25 , wherein the calcium carbonate has a top cut of not more than about 100% of the average diameter of the spunlaid fiber. 
     
     
         32 . The spunlaid fiber of  claim 1 , wherein the spunlaid fiber is meltblown. 
     
     
         33 . The spunlaid fiber of  claim 1 , wherein the spunlaid fiber is spunbonded. 
     
     
         34 . A spunlaid fiber comprising at least one polymeric resin and coated calcium carbonate having a top cut of about 15 microns or less, wherein the coated calcium carbonate is present in the fiber in an amount less than about 40 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         35 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate is present in an amount less than about 25 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         36 . The spunlaid fiber of  claim 35 , wherein the coated calcium carbonate is present in an amount less than about 15 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         37 . The spunlaid fiber of  claim 36 , wherein the coated calcium carbonate is present in an amount less than about 10 wt %, relative to the total weight of the spunlaid fiber. 
     
     
         38 . The spunlaid fiber of  claim 34 , wherein the coating of the coated calcium carbonate is at least one organic material chosen from fatty acids and salts and esters thereof. 
     
     
         39 . The spunlaid fiber of  claim 38 , wherein the at least one organic material is chosen from stearic acid, stearate, ammonium stearate, and calcium stearate. 
     
     
         40 . The spunlaid fiber of  claim 34 , wherein the at least one polymeric resin is chosen from thermoplastic polymers. 
     
     
         41 . The spunlaid fiber of  claim 40 , wherein the thermoplastic polymers are chosen from at least one of polyolefins, polyamides, polyesters, copolymers thereof, and blends thereof. 
     
     
         42 . The spunlaid fiber of  claim 41 , wherein the polyolefins are chosen from polypropylene and polyethylene homopolymers and copolymers. 
     
     
         43 . The spunlaid fiber of  claim 41 , wherein the polyamide is nylon. 
     
     
         44 . The spunlaid fiber of  claim 34 , wherein the at least one polymeric resin has a melt flow rate ranging from about 20 to about 40 g/10 min. 
     
     
         45 . The spunlaid fiber of  claim 34 , further comprising at least one additive chosen from additional mineral fillers, inorganic compounds, waxes, optical brighteners, heat stabilizers, antioxidants, anti-static agents, anti-blocking agents, dyestuffs, pigments, luster improving agents, surfactants, natural oils, and synthetic oils. 
     
     
         46 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has a top cut of about 12 microns. 
     
     
         47 . The spunlaid fiber of  claim 46 , wherein the calcium carbonate has a top cut of about 10 microns. 
     
     
         48 . The spunlaid fiber of  claim 47 , wherein the calcium carbonate has a top cut of about 8 microns. 
     
     
         49 . The spunlaid fiber of  claim 48 , wherein the calcium carbonate has a top cut of about 6 microns. 
     
     
         50 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         51 . The spunlaid fiber of  claim 50 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 12 microns. 
     
     
         52 . The spunlaid fiber of  claim 51 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 10 microns. 
     
     
         53 . The spunlaid fiber of  claim 52 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 8 microns. 
     
     
         54 . The spunlaid fiber of  claim 53 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 6 microns. 
     
     
         55 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has a top cut of not more than about 100% of the average diameter of the spunlaid fiber. 
     
     
         56 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has an average particle size of less than or equal to about 5 microns. 
     
     
         57 . The spunlaid fiber of  claim 56 , wherein the calcium carbonate has an average particle size of less than or equal to about 3 microns. 
     
     
         58 . The spunlaid fiber of  claim 57 , wherein the calcium carbonate has an average particle size of less than or equal to about 1 micron. 
     
     
         59 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 5 microns. 
     
     
         60 . The spunlaid fiber of  claim 59 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 3 microns. 
     
     
         61 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         62 . The spunlaid fiber of  claim 34 , wherein the calcium carbonate has an average particle size of about 1.5 microns. 
     
     
         63 . The spunlaid fiber of  claim 34 , wherein the spunlaid fiber is meltblown. 
     
     
         64 . The spunlaid fiber of  claim 34 , wherein the spunlaid fiber is spunbonded. 
     
     
         65 . A process for producing spunlaid fibers comprising:
 (a) mixing at least one polymeric resin with coated calcium carbonate having an average particle size of less than or equal to about 3 microns;   (b) heating the mixture at least to the softening point of the at least one polymeric resin; and   (c) extruding the mixture to form spunlaid fibers;   wherein the coated calcium carbonate is present in the spunlaid fibers in an amount less than about 40 wt %, relative to the total weight of the spunlaid fibers.   
     
     
         66 . The process of  claim 65 , where in the calcium carbonate has a top cut of about 15 microns or less. 
     
     
         67 . The process of  claim 65 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         68 . The process of  claim 65 , wherein the calcium carbonate has a top cut of not more than about 100% of the average diameter of the spunlaid fiber. 
     
     
         69 . A process for producing a spunlaid fiber comprising:
 (a) producing a masterbatch by mixing and then extruding at least one first polymeric resin with coated calcium carbonate having an average particle size of less than or equal to about 3 microns;   (b) mixing the masterbatch with at least one second polymeric resin to form a resulting mixture, and   (c) extruding the resulting mixture to form spunlaid fibers;   wherein the coated calcium carbonate is present in the spunlaid fibers in an amount less than about 40 wt %, relative to the total weight of the fibers.   
     
     
         70 . The process of  claim 69 , wherein the masterbatch is pelletized before it is mixed with the at least one second polymeric resin. 
     
     
         71 . The process of  claim 69 , wherein the calcium carbonate is present in the masterbatch in an amount ranging from about 20 to about 75 wt %, relative to the total weight of the masterbatch. 
     
     
         72 . The process of  claim 69 , further comprising attenuating the fibers by high-speed drafting. 
     
     
         73 . The process of  claim 69 , where in the calcium carbonate has a top cut of less than about 15 microns. 
     
     
         74 . The process of  claim 69 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         75 . The process of  claim 69 , wherein the calcium carbonate has a top cut of not more than about 100% of the diameter of the spunlaid fiber. 
     
     
         76 . A process for producing a nonwoven fabric comprising:
 (a) mixing at least one polymeric resin with coated calcium carbonate having an average particle size of less than or equal to about 3 microns;   (b) heating the mixture at least to the softening point of the at least one polymeric resin;   (c) extruding the mixture to form fibers;   (d) collecting the fibers on a foraminous surface to form a spunlaid web; and   (e) bonding the spunlaid web to produce a nonwoven fabric;   wherein the calcium carbonate is present in the nonwoven fabric in an amount less than about 40 wt %, relative to the total weight of the fabric.   
     
     
         77 . The process of  claim 76 , wherein the fibers are attenuated by high-speed drafting before being collected on the foraminous surface. 
     
     
         78 . The process of  claim 76 , wherein the nonwoven fabric has a basis weight ranging from about 15 to about 30 gsm. 
     
     
         79 . The process of  claim 76 , wherein the spunlaid web is bonded by a method chosen from at least one of thermal point bonding, ultrasonic bonding, hydroentanglement, and through-air bonding methods. 
     
     
         80 . The process of  claim 76 , further comprising at least one post-treatment process chosen from direction orientation, creping, hydroentanglement, and embossing processes. 
     
     
         81 . The process of  claim 76 , where in the calcium carbonate has a top cut of about 15 microns or less. 
     
     
         82 . The process of  claim 76 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         83 . The process of  claim 76 , wherein the calcium carbonate has a top cut of not more than about 100% of the diameter of the spunlaid fiber. 
     
     
         84 . A process for producing a nonwoven fabric comprising:
 (a) producing a masterbatch by mixing and extruding at least one first polymeric resin with calcium carbonate having an average particle size of less than or equal to about 3 microns;   (b) mixing the masterbatch with at least one second polymeric resin to form a resulting mixture, and   (c) extruding the resulting mixture to form spunlaid fibers;   (d) collecting the fibers on a foraminous surface to form a spunlaid web; and   (e) bonding the spunlaid web to produce a nonwoven fabric;   wherein the calcium carbonate is present in the nonwoven fabric in an amount less than 40 wt %, relative to the total weight of the fibers.   
     
     
         85 . The process of  claim 84 , wherein the masterbatch is pelletized before it is mixed with the at least one second polymeric resin. 
     
     
         86 . The process of  claim 84 , wherein the spunlaid fibers are attenuated by high-speed drafting before being collected on the foraminous surface. 
     
     
         87 . The process of  claim 84 , where in the calcium carbonate has a top cut of about 15 microns or less. 
     
     
         88 . The process of  claim 84 , wherein the calcium carbonate has a top cut ranging from about 4 microns to about 15 microns. 
     
     
         89 . The process of  claim 84 , wherein the calcium carbonate has a top cut of not more than about 100% of the diameter of the spunlaid fiber. 
     
     
         90 . A process for producing spunlaid fibers comprising:
 (a) mixing at least one polymeric resin with coated calcium carbonate having a top cut of about 15 microns or less;   (b) heating the mixture at least to the softening point of the at least one polymeric resin; and   (c) extruding the mixture to form spunlaid fibers;   wherein the coated calcium carbonate is present in the spunlaid fibers in an amount less than about 40 wt %, relative to the total weight of the spunlaid fibers.   
     
     
         91 . The process of  claim 90 , wherein the calcium carbonate has an average particle size of less than or equal to about 5 microns. 
     
     
         92 . The process of  claim 90 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 5 microns. 
     
     
         93 . The process of  claim 90 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         94 . A process for producing a spunlaid fiber comprising:
 (a) producing a masterbatch by mixing and extruding at least one first polymeric resin with coated calcium carbonate having a top cut of about 15 microns or less;   (b) mixing the masterbatch with at least one second polymeric resin to form a resulting mixture, and   (c) extruding the resulting mixture to form spunlaid fibers;   wherein the calcium carbonate is present in the spunlaid fibers in an amount less than about 40 wt %, relative to the total weight of the fibers.   
     
     
         95 . The process of  claim 94 , wherein the masterbatch is pelletized before it is mixed with the at least one second polymeric resin. 
     
     
         96 . The process of  claim 94 , wherein the coated calcium carbonate is present in the masterbatch in an amount ranging from about 20 to about 75 wt %, relative to the total weight of the masterbatch. 
     
     
         97 . The process of  claim 94 , further comprising attenuating the fibers by high-speed drafting. 
     
     
         98 . The process of  claim 94 , wherein the calcium carbonate has an average particle size of less than or equal to about 5 microns. 
     
     
         99 . The process of  claim 94 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 5 microns. 
     
     
         100 . The process of  claim 94 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         101 . A process for producing a nonwoven fabric comprising:
 (a) mixing at least one polymeric resin with coated calcium carbonate having a top cut of about 15 microns or less;   (b) heating the mixture at least to the softening point of the at least one polymeric resin;   (c) extruding the mixture to form fibers;   (d) collecting the fibers on a foraminous surface to form a spunlaid web; and   (e) bonding the spunlaid web to produce a nonwoven fabric;   wherein the calcium carbonate is present in the nonwoven fabric in an amount less than about 40 wt %, relative to the total weight of the fabric.   
     
     
         102 . The process of  claim 101 , wherein the fibers are attenuated by high-speed drafting before being collected on the foraminous surface. 
     
     
         103 . The process of  claim 101 , wherein the nonwoven fabric has a basis weight ranging from about 15 to about 30 gsm. 
     
     
         104 . The process of  claim 101 , wherein the spunlaid web is bonded by a method chosen from at least one of thermal point bonding, ultrasonic bonding, hydroentanglement, and through-air bonding methods. 
     
     
         105 . The process of  claim 101 , further comprising at least one post-treatment process chosen from direction orientation, creping, hydroentanglement, and embossing processes. 
     
     
         106 . The process of  claim 101 , wherein the calcium carbonate has an average particle size of less than or equal to about 5 microns. 
     
     
         107 . The process of  claim 101 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 5 microns. 
     
     
         108 . The process of  claim 101 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         109 . A process for producing a nonwoven fabric comprising:
 (a) producing a masterbatch by mixing and extruding at least one first polymeric resin with coated calcium carbonate having a top cut of about 15 microns or less;   (b) mixing the masterbatch with at least one second polymeric resin to form a resulting mixture, and   (c) extruding the resulting mixture to form spunlaid fibers;   (d) collecting the fibers on a foraminous surface to form a spunlaid web; and   (e) bonding the spunlaid web to produce a nonwoven fabric;   wherein the calcium carbonate is present in the nonwoven fabric in an amount less than about 40 wt %, relative to the total weight of the fibers.   
     
     
         110 . The process of  claim 109 , wherein the masterbatch is pelletized before it is mixed with the at least one second polymeric resin. 
     
     
         111 . The process of  claim 109 , wherein the spunlaid fibers are attenuated by high-speed drafting before being collected on the foraminous surface. 
     
     
         112 . The process of  claim 109 , wherein the calcium carbonate has an average particle size of less than or equal to about 5 microns. 
     
     
         113 . The process of  claim 109 , wherein the calcium carbonate has an average particle size ranging from about 1 micron to about 5 microns. 
     
     
         114 . The process of  claim 109 , wherein the calcium carbonate has an average particle size ranging from about 0.5 microns to about 1.5 microns. 
     
     
         115 . A thermoformed spunlaid fiber comprising at least one polymeric resin and at least one coated filler having an average particle size of less than or equal to about 3 microns and having a top cut of about 15 microns or less, wherein the at least one coated filler is present in the fiber in an amount less than about 40 wt %, relative to the total weight of the thermoformed spunlaid fiber. 
     
     
         116 . A process for producing spunlaid fibers comprising:
 (a) mixing at least one polymeric resin with at least one coated filler having an average particle size of less than or equal to about 3 microns and having a top cut of about 15 microns or less;   (b) heating the mixture at least to the softening point of the at least one polymeric resin; and   (c) extruding the mixture to form spunlaid fibers;   wherein the at least one coated filler is present in the spunlaid fibers in an amount less than about 40 wt %, relative to the total weight of the spunlaid fibers.   
     
     
         117 . A spunlaid fiber comprising at least one polymeric resin and at least one coated filler having an average particle size of less than or equal to about 3 microns, wherein the at least one coated filler is coated calcium carbonate and is present in the fiber in an amount less than about 40 wt %, relative to the total weight of the spunlaid fiber, and wherein the spunlaid fiber has a charge density from about −10 to about −100 volts. 
     
     
         118 . The spunlaid fiber of  claim 117 , wherein the charge density is from about −20 to about −70 volts.