Multi-component fibers, fiber-containing materials made from multi-component fibers and methods of making the fiber-containing materials

Abstract

Disclosed are a multi-component fiber, fiber-containing (e.g., fibrous) material made of multi-component fibers, and methods of forming the fiber-containing material. The fiber-containing material is made of a plurality of multi-component fibers of at least first and second segments. The first and second segments are respectively made of different polymer materials having a high melt temperature and a low melt temperature relative to each other, and the first and second segments are splittable from each other. The fiber-containing material is made by collecting a plurality of the multi-component fibers, splitting the first and second segments from each other, and thermally bonding the fibers by melting the lower melt temperature polymer material of the first segments or second segments. The melted polymer material encapsulates cross-over points of remaining segments, of higher melt temperature polymer material, to act as a binder for the fiber-containing material. The fiber-containing material formed can be, e.g., a yarn, web or fabric, and can have improved strength and softness. According to another aspect of the present invention, a multi-component fiber is made of at least first and second segments which can be split from each other and which are respectively made of different polymer materials having different melt temperatures, a difference in melt temperature between the polymer materials of the first and second segments being, e.g., at least 100° C.

1 . Fiber-containing material including at least first and second polymer materials, the first polymer material being fibrous and having a higher melt temperature than that of the second polymer material, wherein the fiber-containing material has cross-over points of fibers of the first polymer material with each other, where the fibers of the first polymer material cross each other, wherein the second polymer material is substantially only at the cross-over points where the fibers of the first polymer material cross each other, wherein the fiber-containing material is a web or fabric that is self-supporting, and wherein the first polymer material is selected from the group consisting of polyethylene terephthalate, polylactic acid, poly-cyclohexylene dimethylene terephthalate, and polyamides, and the second polymer material is selected from the group consisting of high density polyethylene, linear low density polyethylene, polypropylene, and polylactic acid, the first and second polymer materials being selected such that the melt temperature of the first polymer material is higher than that of the second polymer material.  
   
   
       2 . Fiber-containing material according to  claim 1 , wherein the material is a non-woven fabric.  
   
   
       3 . Fiber-containing material according to  claim 2 , wherein the non-woven fabric has a weight of 0.3 to 40 ounces per square yard.  
   
   
       4 . Fiber-containing material according to  claim 1 , wherein the second polymer material is the sole binder of the fiber-containing material.  
   
   
       5 . Fiber-containing material according to  claim 1 , wherein a difference between the melt temperature of the first polymer material and the melt temperature of the second polymer material is at least 100° C.  
   
   
       6 . Fiber-containing material according to  claim 1 , wherein the first polymer material has a melt temperature in a range of 125°-450° C., and the second polymer material has a melt temperature of 60°-300° C.  
   
   
       7 . Fiber-containing material according to  claim 1 , wherein the material is selected from the group consisting of a hydroentangled fabric, a spunbonded fabric, a wet-laid fabric, an air-laid nonwoven web, a needlepunched nonwoven web and a card web.  
   
   
       8 . Fiber-containing material according to  claim 1 , wherein the second polymer material is substantially only at the cross-over points such that strength and softness of the fiber-containing material are increased as comparied to that when the second polymer material is also located at positions other than the cross-over points.  
   
   
       9 . Fiber-containing material according to  claim 1 , wherein the first and second polymer materials are different types of polymer materials.  
   
   
       10 . A filter comprising the fiber-containing material of  claim 1 .  
   
   
       11 . A wiping cloth comprising the fiber-containing material of  claim 1 .  
   
   
       12 . Synthetic leather comprising the fiber-containing material of  claim 1 .  
   
   
       13 . Synthetic suede comprising the fiber-containing material of  claim 1 .  
   
   
       14 . Fiber-containing material made from a plurality of multi-component fibers, each multi-component fiber including at least first and second segments, the first and second segments being made respectively of a first polymer material and a second polymer material, the first polymer material having a higher melt temperature than that of the second polymer material, the first segments of the plurality of multi-component fibers having cross-over points with each other, where the first segments cross each other, wherein second polymer material, of the second segments, has been melted and is substantially only at the cross-over points where the first segments cross each other, to act as a binder of the fiber-containing material, wherein the multi-component fibers have a size of at most 1 denier per fiber (dpf), wherein the fiber-containing material is self-supporting, and wherein the first polymer material is selected from the group consisting of polyethylene terephthalate, polylactic acid, poly-cyclohexylene dimethylene terephthalate, and polyamides, and the second polymer material is selected from the group consisting of high density polyethylene, linear low density polyethylene, polypropylene, and polylactic acid, the first and second polyrmer materials being selected such that the melt temperature of the first polymer material is higher than that of the second polymer material.  
   
   
       15 . Fiber-containing material according to  claim 14 , wherein the second polymer material, of the second segments, substantially encapsulates said cross-over points and is substantially only at said cross-over points.  
   
   
       16 . Fiber-containing material according to  claim 14 , wherein the first and second segments have been at least partially split by differential shrinkage of the first and second polymer materials.  
   
   
       17 . Fiber-containing material according to  claim 14 , the second segments having been melted and the first polymer material, of the first segments, not having been melted.  
   
   
       18 . Fiber-containing material according to  claim 14 , wherein the difference in melt temperature between the first polymer material and the second polymer material is in the range of 10°-250° C.  
   
   
       19 . Fiber-containing material according to  claim 14 , wherein the second segments have been completely melted in forming the material.  
   
   
       20 . Fiber-containing material according to  claim 14 , wherein the second polymer material, forming the second segments, is the sole binder of the fiber-containing material.  
   
   
       21 . Fiber-containing material according to  claim 14 , wherein the multi-component fibers are microfibers.  
   
   
       22 . Fiber-containing material according to  claim 14 , wherein the second segments have been only partially split from the first segments.  
   
   
       23 . Fiber-containing material according to  claim 22 , wherein the first and second segments are segments that have been split due to differential shrinkage thereof, the segments being self-bulking due to the differential shrinkage.  
   
   
       24 . Fiber-containing material according to  claim 14 , wherein the second segments have been completely split from the first segments prior to melting of the second segments.  
   
   
       25 . Fiber-containing material according to  claim 24 , wherein after completely splitting the first and second segments from each other, to form post-split fibers, the post-split fibers have dpf values less than that of the multi-component fibers, and as low as 0.01 dpf.  
   
   
       26 . Fiber-containing material according to  claim 14 , wherein the fibers are staple fibers.  
   
   
       27 . Fiber-containing material, which is a web or fabric that is self-supporting, and which is made by a process comprising the steps of: 
 collecting a plurality of multi-component fibers, the multi-component fibers having at least first segments and second segments respectively made of first and second polymer materials, the first polymer material having a higher melt temperature than that of the second polymer material, the multi-component fibers having a size of at most 1 denier per fiber (dpf);    splitting the second segments at least partially from the first segments; and    after said splitting, thermally bonding the first segments, to form the fiber-containing material, by melting the second polymer material of the second segments,    wherein in the collecting step, the plurality of multi-component fibers form cross-over points with each other, and in the thermal bonding step the second polymer material of the second segments is melted so as to encapsulate the first segments at cross-over points of the first segments, the first segments crossing each other at the cross-over points of the first segments after the thermal bonding,    wherein after the thermal bonding the second polymer material of the second segments is substantially only at the cross-over points of the first segments, where the first segments cross each other, and    wherein the first polymer material is selected from the group consisting of polyethylene terephthalate, polylactic acid, poly-cyclohexylene dimethylene terephthalate, and polyamides, and the second polymer material is selected from the group consisting of high density polyethylene, linear low density polyethylene, polypropylene, and polylactic acid, the first and second polymer materials being selected such that the melt temperature of the first polymer material is higher than that of the second polymer material.    
   
   
       28 . Fiber-containing material according to  claim 27 , wherein the second polymer material is the only bonding agent thermally bonding the first segments.  
   
   
       29 . Fiber-containing material according to  claim 27 , wherein in the thermal bonding the second polymer material of the second segments is melted without melting the first polymer material of the first segments.  
   
   
       30 . Fiber-containing material according to  claim 27 , wherein the multi-component fibers each contains 4-100 segments and is in a range of 0.7-100 deniers per filament, and after splitting the segments are in a range of 0.01-20 deniers per filament.  
   
   
       31 . Fiber-containing material according to  claim 27 , wherein, in the step of thermally bonding the first segments, the second polymer material of the second segments is completely melted.  
   
   
       32 . Fiber-containing material according to  claim 27 , which is made by a process consisting essentially of said steps.  
   
   
       33 . Fiber-containing material made from a plurality of multi-component fibers, each multi-component fiber including at least first and second segments, the first and second segments being made respectively of a first polymer material and a second polymer material, the first polymer material having a higher melt temperature than that of the second polymer material, the second segments having been melted and being a binder of the fiber-containing material, the first and second segments having been at least partially split from each other prior to melting of the second segments, wherein the fiber-containing material has cross-over points of the first segments with each other, where the first segments cross each other, wherein the second polymer material, of the second segments, is substantially only at the cross-over points where the first segments cross each other, and wherein the fiber-containing material is a yarn.