Patent Publication Number: US-2018044824-A1

Title: Laminated filler and preparation method thereof

Description:
This application claims the priority of Chinese Patent Application No. 201610052601.6, filed with the Chinese Patent Office on Jan. 26, 2016, titled “LAMINATED FILLER AND PREPARATION METHOD THEREOF”, the contents of which are incorporated herein by reference in its entirety. 
     FIELD OF THE INVENTION 
     The present invention relates to the technical field of fillers, particularly to a laminated filler and preparation method thereof. 
     BACKGROUND OF THE INVENTION 
     The traditional production process of batting material is material feeding and mixing-preopening-main opening-carding-lapping-drying-rolling. The above preparation process of batting material can only form a filler in single-layer block structure from a variety of fibers by single carding and lapping, but cannot layer different fibers, and there are defects in the bulkiness and warmness of the product and in the independent delamination of different fibers. 
     SUMMARY OF THE INVENTION 
     In view of the above, the technical problem to be solved by the present invention is to provide a laminated filler and preparation method thereof. The laminated filler provided by the invention has good bulkiness and warmness, and can achieve flexible delamination and diversified combination of different component fibers. 
     The present invention provides a laminated filler, comprising: a first fiber batt ( 1 ) and a second fiber batt ( 2 ) compounded to the first fiber batt. 
     Preferably, it further comprises a third fiber batt ( 3 ) compounded to the second fiber batt. 
     Preferably, the first fiber batt is a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber; and 
     the second fiber batt is selected from a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber. 
     Preferably, the third fiber batt is selected from a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber. 
     Preferably, the natural fiber batt is selected from a TENCEL batt, a wool fiber batt or a bamboo fiber batt; 
     the artificial fiber batt is selected from an artificial fiber batt formed by polyester fiber, coolmax fiber, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber or low melting point fiber; and 
     the mixed fiber batt formed by one or more of natural fiber and artificial fiber is selected from a mixed fiber batt obtained by mixing one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     Preferably, the first fiber batt comprises: 
     5 wt % to 20 wt % of low melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber; 
     0 wt % to 75 wt % of polyester fiber; and 
     20 wt % to 90 wt % of other fibers which are selected from one or more of wool fiber, bamboo fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber and INVISTA fiber; 
     the second fiber batt comprises: 
     5 wt % to 95 wt % of low-melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber, and 
     5 wt % to 95 wt % of polyester fiber or coarse polyester fiber; and 
     the third fiber batt comprises: 
     5 wt % to 20 wt % of low melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber, 
     0 wt % to 75 wt % of polyester fiber; and 
     20 wt % to 90 wt % of other fibers which are selected from one or more of wool fiber, bamboo fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber and INVISTA fiber. 
     Preferably, the fibers of the first fiber batt, the second fiber batt and the third fiber batt have a thickness of 0.7 D to 15 D and a length of 20 to 76 mm. 
     The invention also provides a method for preparing a laminated filler, comprising the following steps: 
     A) mixing by stirring and pre-opening fibers to obtain a first fiber mixture; and 
     mixing by stirring and pre-opening fibers to obtain a second fiber mixture; 
     B) sequentially subjecting the first fiber mixture to main opening, carding and lapping to obtain a first fiber batt precursor; and 
     sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor to obtain a laminated filler precursor; and 
     C) sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain the laminated filler. 
     The invention also provides a method for preparing a laminated filler, which comprises the following steps: 
     A) mixing by stirring and pre-opening fibers to obtain a first fiber mixture; 
     mixing by stirring and pre-opening fibers to obtain a second fiber mixture; and 
     mixing by stirring and pre-opening fibers to obtain a third fiber mixture; 
     B) sequentially subjecting the first fiber mixture to main opening, carding and lapping to obtain a first fiber batt precursor; 
     sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor; and 
     sequentially subjecting the third fiber mixture to main opening, carding and lapping to obtain a third fiber batt precursor laid on the second fiber batt precursor, to obtain a laminated filler precursor; and 
     C) sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain the laminated filler. 
     Preferably, the first fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber; 
     the second fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber; and 
     the third fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     As compared to the prior art, the present invention provides a laminated filler comprising a first fiber batt ( 1 ) and a second fiber batt ( 2 ) compounded to the first fiber batt. In the present invention, by providing the fiber batts in layers, the resulted filler is allowed to have good bulkiness and warmness, and an independent and flexible delamination and diversified combination of different component fibers can be achieved. 
     The results show that the laminated filler provided by the invention has a thickness of 1 to 10 cm and a do value ≧5.0. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic structural view of the laminated filler according to the present invention; 
         FIG. 2  is a schematic structural view of the laminated filler according to the present invention; 
         FIG. 3  is a process flow diagram for preparing the laminated filler according to the present invention; 
         FIG. 4  is a process flow diagram for preparing the laminated filler according to the present invention. 
     
    
    
     DETAILED EMBODIMENTS OF THE INVENTION 
     The present invention provides a laminated filler comprising: a first fiber batt ( 1 ) and a second fiber batt ( 2 ) compounded to the first fiber batt. 
     Referring to  FIG. 1 ,  FIG. 1  is a schematic structural view of the laminated filler according to the present invention. In  FIG. 1, 1  denotes the first fiber batt, and  2  denotes the second fiber batt. 
     In the present invention, the laminated filler comprises a first fiber batt, which is a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber. 
     The natural fiber batt is selected from a TENCEL batt, a wool fiber batt or a bamboo fiber batt. 
     The artificial fiber batt is selected from an artificial fiber batt formed by one or more of polyester fiber, coolmax fiber, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber or low melting point fiber. 
     The mixed fiber batt formed by one or more of natural fiber and artificial fiber is selected from a mixed fiber batt obtained by mixing one or more of the wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     In the present invention, the first fiber batt is preferably a mixed fiber batt formed by one or more of natural fiber and artificial fiber. More preferably, the first fiber batt comprises: 
     5 wt % to 20 wt % of low melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber; 
     0 wt % to 75 wt % of polyester fiber; and 
     20 wt % to 95 wt % of other fibers which are selected from one or more of wool fiber, bamboo fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber and INVISTA fiber. 
     In some embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of (5 to 20):(:(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the first fiber batt is polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and superfine polyester fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and superfine polyester fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the first fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and superfine polyester fiber in a mass ratio of 10:70:20. 
     The laminated filler provided by the present invention further comprises a second fiber batt ( 2 ) compounded to the first fiber batt. 
     In the present invention, the second fiber batt is selected from a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber. 
     The natural fiber batt is selected from a TENCEL batt, a wool fiber batt or a bamboo fiber batt. 
     The artificial fiber batt is selected from an artificial fiber batt formed by polyester fiber, coolmax fiber, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber or low melting point fiber. 
     The mixed fiber batt formed by one or more of natural fiber and artificial fiber is selected from a mixed fiber batt obtained by mixing one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     Preferably, the second fiber batt is selected from a mixed fiber batt formed by one or more of natural fiber and artificial fiber. More preferably, the second fiber batt comprises: 
     5 wt % to 95 wt % of low melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber; and 
     5 wt % to 95 wt % of polyester fiber or coarse polyester fiber. 
     In some particular embodiments of the present invention, the second fiber batt is a mixed fiber batt formed by polyester fiber and low melting point fiber in a mass ratio of 95:5. In other particular embodiments of the present invention, the second fiber batt is a mixed fiber batt formed by polyester fiber and low melting point fiber in a mass ratio of 90:10. In other particular embodiments of the present invention, the second fiber batt is a mixed fiber batt formed by polyester fiber and low melting point fiber in a mass ratio of 85:15. In other particular embodiments of the present invention, the second fiber batt is a mixed fiber batt formed by coarse polyester fiber and low melting point fiber in a mass ratio of 10:90. 
     In the laminated filler having a two-layer structure of the present invention, the thickness of the first fiber batt is preferably 1.0 to 5.0 cm, more preferably 1.1 to 4.5 cm, and the grammage of the first batt is preferably 50 to 200 g/m 2 , and more preferably 50 to 150 g/m 2 . 
     The thickness of the second fiber batt is preferably 1.0 to 5.0 cm, more preferably 1.5 to 4.5 cm, and the grammage of the second batt is preferably 50 to 200 g/m 2 , and more preferably 50 to 150 g/m 2 . 
     The thickness of the laminated filler is preferably 1.0 to 10.0 cm, more preferably 6.0 to 8.0 cm, and the grammage of the laminated filler is preferably 40 to 600 g/m 2 , and more preferably 50 to 450 g/m 2 . 
     In the present invention, the laminated filler may also have a three-layer structure, that is, further comprises a third fiber batt ( 3 ) compounded to the second fiber batt. 
     Referring to  FIG. 2 ,  FIG. 2  is a schematic structural view of the laminated filler according to the present invention. In  FIG. 2, 1  denotes the first fiber batt,  2  denotes the second fiber batt, and  3  denotes the third fiber batt. 
     In the present invention, the third fiber batt is a natural fiber batt, an artificial fiber batt, or a mixed fiber batt formed by one or more of natural fiber and artificial fiber. 
     The natural fiber batt is selected from a TENCEL batt, a wool fiber batt or a bamboo fiber batt. 
     The artificial fiber batt is selected from an artificial fiber batt formed by one or more of polyester fiber, coolmax fiber, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber or low melting point fiber. 
     The mixed fiber batt formed by one or more of natural fiber and artificial fiber is selected from a mixed fiber batt obtained by mixing one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     In the present invention, the third fiber batt is preferably a mixed fiber batt formed by one or more of natural fiber and artificial fiber. More preferably, the third fiber batt comprises: 
     5 wt % to 20 wt % of low melting point fiber, which is polypropylene/polyethylene core-sheath type composite fiber; 
     0 wt % to 75 wt % of polyester fiber; and 
     20 wt % to 90 wt % of other fibers which are selected from one or more of wool fiber, bamboo fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber and INVISTA fiber. 
     In some embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and coolmax fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and TENCEL in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and viscose fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and wool fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and bamboo fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and acrylic fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and milk protein fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and AMICOR fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 5:75:20. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 10:40:50. In other particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and INVISTA fiber in a mass ratio of 15:5:80. 
     In other embodiments of the invention, the third fiber batt is polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and superfine polyester fiber in a mass ratio of (5 to 20):(10 to 75):(20 to 80). In some particular embodiments of the present invention, the third fiber batt is a mixed fiber batt formed by polypropylene/polyethylene core-sheath type composite fiber, polyester fiber and superfine polyester fiber in a mass ratio of 10:70:20. 
     In the laminated filler having a three-layer structure of the present invention, the thickness of the first fiber batt is preferably 1.0 to 5.0 cm, more preferably 1.1 to 4.5 cm, and the grammage of the first fiber batt is preferably 50 to 200 g/m 2 , more preferably 50 to 150 g/m 2 ; 
     the thickness of the second fiber batt is preferably 1.0 to 5.0 cm, more preferably 1.5 to 4.5 cm, and the grammage of the second fiber batt is preferably 50 to 200 g/m 2 , more preferably 50 to 150 g/m 2 ; 
     the thickness of the third fiber batt is preferably 1.0 to 5.0 cm, more preferably 1.5 to 4.5 cm, and the grammage of the third fiber batt is preferably 50 to 200 g/m 2 , more preferably 50 to 150 g/m 2 ; and 
     the thickness of the laminated filler having a three-layer structure is preferably 5.0 to 9.0 cm, more preferably 6.0 to 8.0 cm, and the grammage of the laminated filler is preferably 40 to 600 g/m 2 , more preferably 50 to 450 g/m 2 . 
     All the fiber raw materials used in the laminated filler provided by the present invention preferably have a fiber length of 20 to 76 mm. The fiber raw materials may be a long fiber or a short fiber, or may be a mixed fiber of long fiber and short fiber, wherein the length of the long fiber is more than 30 mm, preferably 32 to 76 mm. The length of the short fiber is less than 30 mm, preferably 20 to 28 mm. 
     The thickness of all the fiber raw materials used in the laminated filler provided by the present invention is preferably 0.7 D to 15 D, and more preferably 1 D to 12 D. 
     The present invention also provides a method for preparing the above laminated filler, comprising the steps of: 
     A) mixing by stirring and pre-opening fibers to obtain a first fiber mixture; and 
     mixing by stirring and pre-opening fibers to obtain a second fiber mixture; 
     B) sequentially subjecting the first fiber mixture to main opening, carding and lapping to obtain a first fiber batt precursor; and 
     sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor to obtain a laminated filler precursor; and 
     C) sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain the laminated filler. 
     Referring to  FIG. 3 ,  FIG. 3  is a process flow diagram for preparing the laminated filler according to the present invention. Specifically, the present method comprises firstly mixing by stirring and pre-opening fibers to obtain a first fiber mixture. 
     In the present invention, the mixing by stirring is preferably carried out in a material feeding and mixing hopper in which various bundled fibers of different specifications in set proportion are uniformly mixed, to obtain a mixed raw material. 
     The pre-opening is carried out in an opener, which preliminary decomposes the mixed raw material to obtain a first fiber mixture. After pre-opening, the first fiber mixture is in a fluffy state, no longer agglomerate, and then is transported by a cotton fan to the next process. 
     The present method also comprises mixing by stirring and pre-opening fibers to obtain a second fiber mixture. 
     In the present, the mixing by stirring is preferably carried out in a material feeding and mixing hopper in which various bundled fibers of different specifications in set proportion are uniformly mixed, to obtain a mixed raw material. 
     The pre-opening is carried out in the opener, which preliminary decomposes the mixed raw material to obtain the second fiber mixture. After pre-opening, the second fiber mixture is in a fluffy state, no longer agglomerate, and then is transported by a cotton fan to the next process. 
     In the present invention, the order of the preparation of the first fiber mixture and the preparation of the second fiber mixture is not particularly limited. 
     After obtaining the first fiber mixture, the first fiber mixture is sequentially subjected to main opening, carding and lapping to obtain a first fiber batt precursor. 
     Specifically, the first fiber batt precursor is prepared as follows: 
     the first fiber mixture is further opened in the opener for main opening, so that the first fiber mixture is completely opened and the raw material is in a fluffy state. 
     After the main opening, the first fiber mixture forms a compact first sheet cotton in a material storage cabinet and the raw material is accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the first sheet cotton is fed through a cotton feeder into a carding machine for carding into web, in which the first sheet cotton is straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. In the present invention, the carding machine is preferably a double-cylinder carding machine. 
     Then, a lapping operation is performed to obtain a first fiber batt precursor. Specifically, according to customer requirements, the width and grammage are adjusted according to process requirements, and the fiber web exported from the carding machine is evenly folded, and then laid to the required width and thickness. 
     The present method further comprises sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor to obtain a laminated filler precursor. 
     Specifically, the laminated filler precursor is prepared as follows: 
     the second fiber mixture is further opened in the opener for the main opening, so that the second fiber mixture is completely opened and the decomposition of raw material is clearer and more uniform, and then are transported to a cotton storage bin of a cotton feeder by a cotton fan. 
     After the main opening, the second fiber mixture forms a compact second sheet cotton in a material storage cabinet and the raw material is accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the second sheet cotton is fed by a cotton feeder into a carding machine for carding into web, in which the second sheet cotton is straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. In the present invention, the carding machine is preferably a double-cylinder carding machine. 
     Then, a lapping operation is performed to obtain a second fiber batt precursor. Specifically, when lapping the second fiber batt precursor, the second fiber batt precursor is laid on the first fiber batt precursor. Meantime, according to customer requirements, the width and grammage are adjusted according to process requirements, and the fiber wet exported from the carding machine is evenly folded, and then laid to the required width and thickness. A laminated filler precursor in which the first fiber batt precursor/second fiber batt precursor are compounded is obtained. 
     The present method comprises sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain a laminated filler. 
     In the present invention, the drawing is preferably performed with a five-roll traction machine to ensure smoothness of the product. In the present invention, the rate of the drawing is preferably 1200 to 1300 rpm. 
     The drying is to vaporize the moisture in the product which has been laid, to ensure the drying of the product, and to dissolve and solidify the viscid thread in the product to ensure the pulling force and shape of the product. The drying is preferably conducted at a temperature of 170 to 180° C. 
     After the completion of drying, the product is ironed to increase the adhesion and fastness of the product, to ensure that there is no separation and loss of fibers during hand washing. In the present invention, the temperature for the ironing is preferably 180 to 200° C., and the rotational speed of the ironing machine is 40 to 50 Hz. 
     After ironing, cooling the ironed laminated filler precursor to obtain a laminated filler. In the present invention, the cooling is preferably performed by using an air cooling machine. 
     Preferably, the laminated filler obtained is rolled and cut, and each product is quantified on demand to facilitate stacking and handling. 
     The present invention also provides a method for preparing a laminated filler, comprising the steps of: 
     A) mixing by stirring and pre-opening fibers to obtain a first fiber mixture; 
     mixing by stirring and pre-opening fibers to obtain a second fiber mixture; and 
     mixing by stirring and pre-opening fibers to obtain a third fiber mixture; 
     B) sequentially subjecting the first fiber mixture to main opening, carding and lapping to obtain a first fiber batt precursor; 
     sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor; and 
     sequentially subjecting the third fiber mixture to main opening, carding and lapping to obtain a third fiber batt precursor laid on the second fiber batt precursor to obtain a laminated filler precursor; and 
     C) sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain the laminated filler. 
     Referring to  FIG. 4 ,  FIG. 4  is a process flow diagram for preparing the laminated filler according to the present invention. A filler having a three-layer structure is prepared by using the above-mentioned preparation method. 
     Specifically, the present method comprises firstly mixing by stirring and pre-opening fibers to obtain a first fiber mixture. 
     In the present method, the mixing by stirring is preferably carried out in a material feeding and mixing hopper in which various bundled fibers of different specifications in set proportion are uniformly mixed, to obtain a mixed raw material. 
     The pre-opening is carried out in the opener, which preliminary decomposes the mixed raw material to obtain a first fiber mixture. After pre-opening, the first fiber mixture is in a fluffy state, no longer agglomerate, and then is transported by a cotton fan to the next process. 
     The present method also comprises mixing by stirring and pre-opening fibers to obtain a second fiber mixture. 
     In the present method, the mixing by stirring is preferably carried out in a material feeding and mixing hopper in which various bundled fibers of different specifications in set proportion are uniformly mixed, to obtain a mixed raw material. 
     The pre-opening is carried out in the opener, which preliminary decomposes the mixed raw material to obtain the second fiber mixture. After pre-opening, the second fiber mixture is in a fluffy state, no longer agglomerate, and then is transported by a cotton fan to the next process. 
     The present method also comprises firstly mixing by stirring and pre-opening fibers to obtain a third fiber mixture. 
     In the present invention, the mixing by stirring is preferably carried out in a material feeding and mixing hopper in which various bundled fibers of different specifications in set proportion are uniformly mixed, to obtain a mixed raw material. 
     The pre-opening is carried out in the opener, which preliminary decomposes the mixed raw material to obtain the third fiber mixture. After pre-opening, the third fiber mixture is in a fluffy state, no longer agglomerate, and then is transported by a cotton fan to the next process. 
     In the present invention, the order of the preparation of the first fiber mixture, the preparation of the second fiber mixture and the preparation of the third fiber mixture is not particularly limited. 
     After obtaining the first fiber mixture, the first fiber mixture is sequentially subjected to main opening, carding and lapping to obtain a first fiber batt precursor. 
     Specifically, the first fiber batt precursor is prepared as follows: 
     the first fiber mixture is further opened in the opener for the main opening, so that the first fiber mixture is completely opened and the raw material is in a fluffy state. 
     After the main opening, the first fiber mixture forms a compact first sheet cotton in a collector and the raw material is accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the first sheet cotton is fed through a cotton feeder into a carding machine for carding into web, in which the first sheet cotton is straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. In the present invention, the carding machine is preferably a double-cylinder carding machine. 
     Then, a lapping operation is performed to obtain a first fiber batt precursor. Specifically, according to customer requirements, the width and grammage are adjusted according to process requirements, and the fiber wet exported from the carding machine is evenly folded, and then laid to the required width and thickness. 
     The present method further comprises sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a second fiber batt precursor laid on the first fiber batt precursor. 
     Specifically, the second fiber mixture is further opened in the opener for main opening so that the second fiber mixture is completely opened and the decomposition of raw material is clearer and more uniform, and then are transported to a cotton storage bin of a cotton feeder by a cotton fan. 
     After the main opening, the second fiber mixture forms a compact second sheet cotton in a material storage cabinet and the raw material is accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the second sheet cotton is fed through a cotton feeder into a carding machine for carding into web, in which the second sheet cotton is straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. In the present invention, the carding machine is preferably a double-cylinder carding machine. 
     Then, a lapping operation is performed to obtain a second fiber batt precursor. Specifically, when lapping the second fiber batt precursor, the second fiber batt precursor is laid on the first fiber batt precursor. Meantime, according to customer requirements, the width and grammage are adjusted according to process requirements, and the fiber wet exported from the carding machine is evenly folded, and then laid to the required width and thickness. 
     The present method further comprises sequentially subjecting the second fiber mixture to main opening, carding and lapping to obtain a third fiber batt precursor laid on the second fiber batt precursor to obtain a laminated filler precursor. 
     Specifically, the laminated filler precursor is prepared as follows: 
     the third fiber mixture is further opened in the opener for main opening, so that the third fiber mixture is completely opened and the decomposition of raw material is clearer and more uniform, and then are transported to a cotton storage bin of a cotton feeder by a cotton fan. 
     After the main opening, the third fiber mixture forms a compact third sheet cotton in a material storage cabinet and the raw material is accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the third sheet cotton is fed through a cotton feeder into a carding machine for carding into web, in which the third sheet cotton is straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. In the present invention, the carding machine is preferably a double-cylinder carding machine. 
     Then, a lapping operation is performed to obtain a third fiber batt precursor. Specifically, when lapping the third fiber batt precursor, the third fiber batt precursor is laid on the second fiber batt precursor. Meantime, according to customer requirements, the width and grammage are adjusted according to process requirements, and the fiber wet exported from the carding machine is evenly folded, and then laid to the required width and thickness, to obtain a laminated filler precursor in which the first fiber batt precursor/second fiber batt precursor/the third fiber batt precursor are compounded. 
     The present method comprises sequentially subjecting the laminated filler precursor to drawing, drying, ironing and cooling to obtain a laminated filler. 
     In the present invention, the drawing is preferably performed with a five-roll traction machine to ensure smoothness of the product. In the present invention, the rate of the drawing is preferably 1200 to 1300 rpm. 
     The drying is to vaporize the moisture of the product which has been laid, to ensure the drying of the product, and to dissolve and solidify the viscid thread in the product to ensure the pulling force and shape of the product. The drying is preferably conducted at a temperature of 170 to 180° C. 
     After drying, the product is ironed to increase the adhesion and fastness of the product, to ensure that there is no separation and loss of fibers during hand washing. In the present invention, the temperature of the ironing is preferably 180 to 200° C., and the rotational speed of the ironing machine is 40 to 50 Hz. 
     After ironing, cooling the ironed laminated filler precursor to obtain a laminated filler. In the present invention, the cooling is preferably performed by using an air cooling machine. 
     Preferably, the laminated filler obtained is rolled and cut, and each product is quantified on demand to facilitate stacking and handling. 
     In the preparation methods described above, the first fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber; 
     The second fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL fiber, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber; and 
     The third fiber mixture comprises one or more of wool fiber, bamboo fiber, polyester fiber, coolmax fiber, TENCEL, superfine polyester fiber, coarse polyester fiber, viscose fiber, acrylic fiber, milk protein fiber, AMICOR fiber, INVISTA fiber and low melting point fiber. 
     The filler according to the present invention can be used in apparel, beddings, ornaments, car trims and the like in which it can be filled. 
     In the present invention, by arranging the fiber batts in layers, the obtained filler has good bulkiness and warmness 
     The results show that the laminated filler provided by the invention has a thickness of 6.5 to 9 cm and a do value ≧5.15. 
     In order to further understand the present invention, the laminated filler and the preparation method thereof according to the present invention will be described with reference to the following examples. The scope of the present invention is not limited by the following examples. 
     In the following examples, the raw material specifications are as follows: 
     Polyester fiber includes: 3D*64 MM three-dimensional hollow siliceous small chemical fiber, 7D*64 MM three-dimensional hollow siliceous small chemical fiber, and polyester fiber 6D*64 MM two-dimensional hollow small chemical fiber; 
     low melting point fiber: 4D*51 MM polypropylene/polyethylene core-sheath type composite fiber; 
     coolmax fiber: 1.6D*38 MM coolmax fiber; 
     TENCEL fiber: 6.7D*60 MM siliceous TENCEL fiber; 
     viscose fiber: 1.67D*38 MM viscose fiber; 
     wool fiber: 60*30 MM wool fiber; 
     bamboo fiber: 1.2D*38 MM bamboo fiber; 
     acrylic fiber: 3D*60 MM acrylic fiber; 
     milk protein fiber: 1.5D*51 MM milk protein fiber; 
     AMICOR fiber: 6D*64 MM AMICOR fiber; 
     INVISTA fiber: 4.2D*76 MM Siliceous DS4 INVISTA fiber; 
     polyester ultra-fine fibers include: polyester fine denier fiber 1.2D*51 MM two-dimensional siliceous small chemical fiber; 
     coarse polyester fiber: 12D*64 MM two-dimensional hollow siliceous small chemical fiber. 
     Examples 1-28 
     Examples 1-28 are methods for preparing fillers having a two-layer structure, specifically: 
     According to the formulations of raw materials in Table 1, various bundled fibers of different specifications which were used for preparation of the first fiber batt were uniformly mixed in set proportion in a material feeding and mixing hopper, to obtain a mixed raw material. 
     The obtained mixed raw material was preliminarily decomposed in an opener, making the mixed raw material in a fluffy state, no longer agglomerate, to form a first fiber mixture, which was then transported by a cotton fan to the next process. 
     Meantime, according to the formulations of raw materials in Table 1, various bundled fibers of different specifications which were used for preparation of the second fiber batt were uniformly mixed in set proportion in a material feeding and mixing hopper, to obtain a mixed raw material. 
     The obtained mixed raw material were preliminarily decomposed in an opener with a rotational speed of 1440 Y/min, making the mixed raw material in a fluffy state, no longer agglomerate, to form a second fiber mixture, which was then transported by a cotton fan to the next process. 
     The obtained first fiber mixture and second fiber mixture were separately transported to two openers for main opening, which made the mixed fibers completely opened. The rotational speed of the opener was 1440 Y/min. 
     After the main opening, the first fiber mixture formed a compact first sheet cotton in a material storage cabinet (the size of the material storage cabinet was 200 cm*280 cm*170 cm) and the raw material was accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the first sheet cotton was fed through a cotton feeder in a speed of 750 rpm into a double-cylinder carding machine for carding into web, particularly, the opened raw material was fed into a cylinder having a rotational speed of 1200 r/min and a doffer of 48 Hz for carding molding, in which the first sheet cotton was straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. 
     Then, a lapping operation was performed to obtain a first fiber batt precursor. Specifically, the width and grammage were adjusted according to process requirements to ensure the product quality, and the fiber wet exported from the carding machine was evenly folded, and then laid to the required width and thickness. In which, the slant curtain of the lapping machine was 38.25 Hz, the ring curtain was 23.9 Hz, the bottom curtain was 27 Hz, and the reciprocating curtain was 40 Hz. 
     After the main opening, the second fiber mixture formed a compact second sheet cotton in a material storage cabinet (the size of the material storage cabinet was 200 cm*280 cm*170 cm) and the raw material was accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the second sheet cotton was fed through a cotton feeder in a speed of 750 rpm into a double-cylinder carding machine for carding, specifically, the opened raw material was fed into a cylinder having a speed of 1200 r/min and a doffer of 48 Hz for carding molding, in which the second sheet cotton was straightened by fine decomposition and was processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. 
     Then, a lapping operation was performed to lay the second fiber batt precursor on the first fiber batt precursor to obtain a laminated filler precursor in which the first fiber batt precursor/second fiber batt precursor were compounded. Specifically, the width and grammage were adjusted according to process requirements to ensure the product quality, and the fiber wet exported from the carding machine was evenly folded, and then laid to the required width and thickness. In which, the slant curtain of the lapping machine is 38.25 Hz, the ring curtain was 23.9 Hz, the bottom curtain was 27 Hz, and the reciprocating curtain was 40 Hz. 
     The laminated filler precursor was pulled in a five-roll traction machine with rate of the drawing of 1250 rpm to ensure smoothness of the product. 
     After drawing, the moisture of the product which had been laid was evaporated to ensure the drying of the product, and to dissolve and solidify the viscid thread in the product to ensure the pulling force and shape of the product. The drying is preferably conducted at a temperature of 170° C. 
     After the completion of drying, the product was ironed to increase the adhesion and fastness of the product, to ensure that there was no separation and loss of fibers during hand washing. Wherein, the temperature of the ironing was 200° C., and the rotational speed of the ironing machine was 45 Hz. 
     After ironing, the ironed laminated filler precursor was cooled and fixed by blowing the inner ring using a fan with a rotational speed of 1430 Y/min, to obtain a laminated filler precursor. 
     Finally, the product was obtained by rolling with a determined amount of one meter per 22 laps and a speed of 1200 rpm. The product performance was measured, with the results shown in Table 2. Table 2 shows the measurement results of the performances of the filler having a two-layer structure as prepared in Examples 1-28. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Raw material formulations for the laminated filler having a two-layer structure 
               
            
           
           
               
               
               
            
               
                   
                 The raw materials of the first fiber batt and 
                 The raw materials of the second fiber 
               
               
                 Examples 
                 the weight ratios thereof 
                 batt and the weight ratios thereof 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 Example 1 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 2 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 3 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 4 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 5 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 6 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 7 
                 superfine polyester fiber, low melting point fiber 
                 95%, 5% 
                 low melting point fiber, coarse polyester fiber 
                 90%, 10% 
               
               
                 Example 8 
                 viscose fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 9 
                 viscose fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 10 
                 viscose fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 11 
                 wool fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 12 
                 wool fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 13 
                 wool fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 14 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 15 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 16 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 17 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 18 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 19 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 20 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 21 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 22 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 23 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 24 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 25 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 26 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 27 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 28 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                   
               
            
           
         
       
     
     In Table 1, 6D*64 MM type two-dimensional hollow small chemical fiber was selected for the polyester fiber of the first fiber batt in Examples 2, 5, 6, 9, 10, 15, 16, 21, 22, 24 and 25, 7D*64 MM type three-dimensional hollow siliceous small chemical fiber was selected for the polyester fiber of the first fiber batt in Example 3, and 3D*64 MM type three-dimensional hollow siliceous small chemical fiber was selected for the polyester fiber in the first fiber batt of Examples other than the above Examples. 
     7D*64 MM type three-dimensional hollow siliceous small chemical fiber was selected for the polyester fiber of the second fiber batt in Examples 1, 4, 8, 11, 14, 17, 20, 23 and 26, and 6D*64 MM type two-dimensional hollow small chemical fiber was selected for the polyester fiber in the second fiber batt of Examples other than the above Examples. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Performances of the filler in two-layer structure prepared in Examples 1-28 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                 The thickness of 
                 The grammage of 
                 The thickness of 
                 The grammage of 
                 The grammage of 
                   
                 Clo value 
               
               
                   
                 the first fiber 
                 the first fiber 
                 the second fiber 
                 the second fiber 
                 the laminated 
                 The thickness of 
                 (warmness 
               
               
                 Examples 
                 batt/cm 
                 batt/g/m 2   
                 batt/cm 
                 bat/g/m 2   
                 filler/g/m 2   
                 the filler/cm 
                 value TOG) 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Example 1 
                 3.2 
                 140 
                 3.5 
                 130 
                 270 
                 6.7 
                 5.21 
               
               
                 Example 2 
                 3.1 
                 140 
                 3.5 
                 130 
                 270 
                 6.6 
                 5.35 
               
               
                 Example 3 
                 2.9 
                 140 
                 3.5 
                 130 
                 270 
                 6.4 
                 5.50 
               
               
                 Example 4 
                 3.9 
                 150 
                 3.8 
                 190 
                 340 
                 7.7 
                 5.42 
               
               
                 Example 5 
                 4.1 
                 150 
                 3.8 
                 190 
                 340 
                 7.9 
                 5.75 
               
               
                 Example 6 
                 4.3 
                 150 
                 3.8 
                 190 
                 340 
                 8.1 
                 6.15 
               
               
                 Example 7 
                 3.2 
                 140 
                 3.7 
                 130 
                 270 
                 6.9 
                 5.30 
               
               
                 Example 8 
                 2.8 
                 100 
                 3.1 
                 100 
                 200 
                 5.9 
                 5.28 
               
               
                 Example 9 
                 2.7 
                 100 
                 3.1 
                 100 
                 200 
                 5.8 
                 5.39 
               
               
                 Example 10 
                 2.5 
                 100 
                 3.1 
                 100 
                 200 
                 5.6 
                 5.61 
               
               
                 Example 11 
                 3.8 
                 140 
                 3.6 
                 160 
                 300 
                 7.4 
                 7.42 
               
               
                 Example 12 
                 4.0 
                 140 
                 3.6 
                 160 
                 300 
                 7.6 
                 7.80 
               
               
                 Example 13 
                 4.2 
                 140 
                 3.6 
                 160 
                 300 
                 7.8 
                 8.22 
               
               
                 Example 14 
                 2.6 
                 70 
                 3.1 
                 100 
                 170 
                 5.7 
                 5.25 
               
               
                 Example 15 
                 2.5 
                 70 
                 3.1 
                 100 
                 170 
                 5.6 
                 5.41 
               
               
                 Example 16 
                 2.4 
                 70 
                 3.1 
                 100 
                 170 
                 5.5 
                 5.75 
               
               
                 Example 17 
                 3.0 
                 120 
                 3.2 
                 120 
                 240 
                 6.2 
                 5.38 
               
               
                 Example 18 
                 2.8 
                 120 
                 3.2 
                 120 
                 240 
                 6.0 
                 5.70 
               
               
                 Example 19 
                 2.6 
                 120 
                 3.2 
                 120 
                 240 
                 5.8 
                 6.06 
               
               
                 Example 20 
                 3.2 
                 140 
                 3.5 
                 130 
                 270 
                 6.7 
                 5.28 
               
               
                 Example 21 
                 3.1 
                 140 
                 3.5 
                 130 
                 270 
                 6.6 
                 5.45 
               
               
                 Example 22 
                 2.9 
                 140 
                 3.5 
                 130 
                 270 
                 6.4 
                 5.80 
               
               
                 Example 23 
                 4.0 
                 170 
                 4.1 
                 170 
                 340 
                 8.1 
                 5.85 
               
               
                 Example 24 
                 4.1 
                 170 
                 4.1 
                 170 
                 340 
                 8.2 
                 6.13 
               
               
                 Example 25 
                 4.3 
                 170 
                 4.1 
                 170 
                 340 
                 8.4 
                 6.58 
               
               
                 Example 26 
                 4.0 
                 170 
                 4.1 
                 170 
                 340 
                 8.1 
                 6.35 
               
               
                 Example 27 
                 4.1 
                 170 
                 4.1 
                 170 
                 340 
                 8.2 
                 6.77 
               
               
                 Example 28 
                 4.3 
                 170 
                 4.1 
                 170 
                 340 
                 8.4 
                 7.92 
               
               
                   
               
            
           
         
       
     
     Examples 29-56 
     Examples 29-56 are methods for preparing the filler having a two-layer structure, specifically: 
     According to the formulations of raw materials in Table 3, various bundled fibers of different specifications which were used for preparation of the first fiber batt were uniformly mixed in set proportion in a material feeding and mixing hopper, to obtain a mixed raw material. 
     The obtained mixed raw material were preliminarily decomposed in an opener, making the mixed raw material in a fluffy state, no longer agglomerate, to form a first fiber mixture, which was then transported by a cotton fan to the next process. 
     Meantime, according to the formulations of raw materials in Table 3, various bundled fibers of different specifications which were used for preparation of the second fiber batt were uniformly mixed in set proportion in a material feeding and mixing hopper, to obtain a mixed raw material. 
     The obtained mixed raw material were preliminarily decomposed in an opener with a rotational speed of 1440 Y/min, making the mixed raw material in a fluffy state, no longer agglomerate, to form a second fiber mixture, which was then transported by a cotton fan to the next process. 
     Meantime, according to the formulations of raw materials in Table 3, various bundled fibers of different specifications which were used for preparation of the third fiber batt were uniformly mixed in set proportion in a material feeding and mixing hopper, to obtain a mixed raw material. 
     The obtained mixed raw material were preliminarily decomposed in an opener with a rotational speed of 1440 Y/min, making the mixed raw material in a fluffy state, no longer agglomerate, to form a third fiber mixture, which was then transported by a cotton fan to the next process. 
     The obtained first fiber mixture, second fiber mixture and third fiber mixture were separately transported to three openers for main opening, which made the mixed fiber completely opened. The rotational speed of the openers was 1440 Y/min. 
     After the main opening, the first fiber mixture formed a compact first sheet cotton in a material storage cabinet (the size of the material storage cabinet was 200 cm*280 cm*170 cm) and the raw material was accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the first sheet cotton was fed through a cotton feeder in a speed of 750 rpm into a double-cylinder carding machine for carding into web, particularly, the opened raw material was fed into a cylinder having a rotational speed of 1200 r/min and a doffer of 48 Hz for carding molding, in which the first sheet cotton was straightened by fine decomposition and is processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. 
     Then, a lapping operation was performed to obtain a first fiber batt precursor. Specifically, the width and grammage were adjusted according to process requirements to ensure product quality, and the fiber wet exported from the carding machine was evenly folded, and then laid to the required width and thickness. In which, the slant curtain of the lapping machine was 38.25 Hz, the ring curtain was 23.9 Hz, the bottom curtain was 27 Hz, and the reciprocating curtain was 40 Hz. 
     After the main opening, the second fiber mixture formed a compact second sheet cotton in a material storage cabinet (the size of the material storage cabinet was 200 cm*280 cm*170 cm) and the raw material was accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the second sheet cotton was fed through a cotton feeder in a speed of 750 rpm into a double-cylinder carding machine for carding into web, particularly, the opened raw material was fed into a cylinder having a speed of 1200 r/min and a doffer of 48 Hz for carding molding, in which the second sheet cotton was straightened by fine decomposition and was processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. 
     Then, a lapping operation was performed to obtain a second fiber batt precursor. Specifically, the width and grammage were adjusted according to process requirements to ensure product quality, and the fiber wet exported from the carding machine was evenly folded, and then laid to the required width and thickness. In which, the slant curtain of the lapping machine was 38.25 Hz, the ring curtain was 23.9 Hz, the bottom curtain was 27 Hz, and the reciprocating curtain was 40 Hz. 
     After the main opening, the third fiber mixture formed a compact third sheet cotton in a material storage cabinet (the size of the material storage cabinet was 200 cm*280 cm*170 cm) and the raw material was accumulated to ensure uniform supply during carding and the stability of grammage. 
     Then, the third sheet cotton was fed through a cotton feeder in a speed of 750 rpm into a double-cylinder carding machine for carding into web, particularly, the opened raw material was fed into a cylinder having a speed of 1200 r/min and a doffer of 48 Hz for carding molding, in which the third sheet cotton was straightened by fine decomposition and was processed into a quantitative fiber web consisting essentially of single fibers and then fed to the subsequent step. 
     Then, a lapping operation was performed to lay the third fiber batt precursor on the second fiber batt precursor to obtain a laminated filler precursor in which the first fiber batt precursor/second fiber batt precursor/third fiber batt precursor were compounded. Specifically, the width and grammage were adjusted according to process requirements to ensure product quality, and the fiber wet exported from the carding machine was evenly folded, and then laid to the required width and thickness. In which, the slant curtain of the lapping machine was 38.25 Hz, the ring curtain was 23.9 Hz, the bottom curtain was 27 Hz, and the reciprocating curtain was 40 Hz. 
     The laminated filler precursor was pulled in a five-roll traction machine with a drawing speed of 1250 rpm to ensure smoothness of the product. 
     After drawing, the moisture of the product which had been laid was evaporated to ensure the drying of the product, and to dissolve and solidify the viscid thread in the product to ensure the pulling force and shape of the product. The drying is preferably conducted at a temperature of 170° C. 
     After the completion of drying, the product was ironed to increase the adhesion and fastness of the product, to ensure that there was no separation and loss of fibers during hand washing. Wherein, the temperature of the ironing was 200° C., and the rotational speed of the ironing machine was 45 Hz. 
     After ironing, the ironed laminated filler precursor was cooled and fixed by blowing the inner ring using a fan with a rotational speed of 1430 Y/min, to obtain a laminated filler. 
     Finally, the product was obtained by rolling with a determined amount of one meter per 22 laps and a speed of 1200 rpm. The product performance was measured, with the results shown in Table 4. Table 4 shows the measurement results of the performances of the filler having a three-layer structure as prepared in Examples 29-56. 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Raw material formulations for the laminated filler having a three-layer structure 
               
            
           
           
               
               
               
            
               
                   
                 The raw materials of the first and third fiber 
                 The raw materials of the second fiber 
               
               
                 Examples 
                 batts and the weight ratios thereof 
                 batt and the weight ratios thereof 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 Example 29 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 30 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 31 
                 coolmax fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 32 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 33 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 34 
                 TENCEL fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 35 
                 superfine polyester fiber, low melting point fiber 
                 90%, 10% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 36 
                 viscose fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 37 
                 viscose fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 38 
                 viscose fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 39 
                 wool fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 40 
                 wool fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 41 
                 wool fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 42 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 43 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 44 
                 bamboo fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 45 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 46 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 47 
                 acrylic fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 48 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 49 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 50 
                 milk protein fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 51 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 52 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 53 
                 AMICOR fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                 Example 54 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 20%, 75%, 5% 
                 low melting point fiber, polyester fiber 
                 5%, 95% 
               
               
                 Example 55 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 50%, 40%, 10% 
                 low melting point fiber, polyester fiber 
                 10%, 90% 
               
               
                 Example 56 
                 INVISTA fiber, polyester fiber, low melting point fiber 
                 80%, 5%, 15% 
                 low melting point fiber, polyester fiber 
                 15%, 85% 
               
               
                   
               
            
           
         
       
     
     In Table 3, the first fiber batts and the third fiber batts in Examples 29-56 used raw materials at the same mass ratio, wherein 3D*64 MM type three-dimensional hollow siliceous small chemical fiber was selected for the polyester fibers; 6D*64 MM type two-dimensional hollow small chemical fiber was selected for the polyester fibers of the second fiber batts in Examples 8-10 and 14-19, and 7D*64 MM type three-dimensional hollow siliceous small chemical fiber was selected for the polyester fibers of the second fiber batts in Examples 1-7, 11-13 and 20-28. 
     
       
         
           
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                 Performances of the filler in two-layer structure prepared in Examples 29-56 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                   
                   
                 The 
                   
                 The 
                   
                 The 
                 The 
                   
                   
               
               
                   
                 The 
                 grammage 
                 The 
                 grammage 
                 The 
                 grammage 
                 grammage 
                 The 
               
               
                   
                 thickness of 
                 of the first 
                 thickness of 
                 of the 
                 thickness of 
                 of the third 
                 of the 
                 thickness 
                 Clo value 
               
               
                   
                 the first 
                 fiber 
                 the second 
                 second fiber 
                 the third 
                 fiber 
                 laminated 
                 of the 
                 (warmness 
               
               
                 Examples 
                 fiber batt/cm 
                 batt/g/m 2   
                 fiber batt/cm 
                 bat/g/m 2   
                 fiber batt/cm 
                 batt/g/m 2   
                 filler/g/m 
                 filler/cm 
                 value TOG) 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 Example 29 
                 1.1 
                 50 
                 3.7 
                 140 
                 1.1 
                 50 
                 240 
                 6.0 
                 5.23 
               
               
                 Example 30 
                 1.1 
                 50 
                 3.7 
                 140 
                 1.1 
                 50 
                 240 
                 5.9 
                 5.37 
               
               
                 Example 31 
                 1.0 
                 50 
                 3.7 
                 140 
                 1.0 
                 50 
                 240 
                 5.8 
                 5.52 
               
               
                 Example 32 
                 2.1 
                 115 
                 3.2 
                 110 
                 2.1 
                 115 
                 340 
                 7.4 
                 5.62 
               
               
                 Example 33 
                 2.2 
                 115 
                 3.2 
                 110 
                 2.2 
                 115 
                 340 
                 7.7 
                 5.95 
               
               
                 Example 34 
                 2.3 
                 115 
                 3.2 
                 110 
                 2.3 
                 115 
                 340 
                 7.9 
                 6.35 
               
               
                 Example 35 
                 2.3 
                 100 
                 2.0 
                 70 
                 2.3 
                 100 
                 270 
                 6.6 
                 5.56 
               
               
                 Example 36 
                 1.1 
                 50 
                 4.0 
                 170 
                 1.1 
                 50 
                 270 
                 6.3 
                 5.30 
               
               
                 Example 37 
                 1.1 
                 50 
                 4.0 
                 170 
                 1.1 
                 50 
                 270 
                 6.2 
                 5.41 
               
               
                 Example 38 
                 1.0 
                 50 
                 4.0 
                 170 
                 1.0 
                 50 
                 270 
                 6.1 
                 5.63 
               
               
                 Example 39 
                 2.1 
                 115 
                 4.0 
                 170 
                 2.1 
                 115 
                 400 
                 8.2 
                 7.44 
               
               
                 Example 40 
                 2.2 
                 115 
                 4.0 
                 170 
                 2.2 
                 115 
                 400 
                 8.5 
                 7.82 
               
               
                 Example 41 
                 2.3 
                 115 
                 4.0 
                 170 
                 2.3 
                 115 
                 400 
                 8.7 
                 8.24 
               
               
                 Example 42 
                 1.1 
                 50 
                 3.7 
                 140 
                 1.1 
                 50 
                 240 
                 6.0 
                 5.27 
               
               
                 Example 43 
                 1.1 
                 50 
                 3.7 
                 140 
                 1.1 
                 50 
                 240 
                 5.9 
                 5.43 
               
               
                 Example 44 
                 1.0 
                 50 
                 3.7 
                 140 
                 1.0 
                 50 
                 240 
                 5.8 
                 5.77 
               
               
                 Example 45 
                 1.2 
                 50 
                 4.0 
                 170 
                 1.2 
                 50 
                 270 
                 6.4 
                 5.40 
               
               
                 Example 46 
                 1.1 
                 50 
                 4.0 
                 170 
                 1.1 
                 50 
                 270 
                 6.3 
                 5.72 
               
               
                 Example 47 
                 1.1 
                 50 
                 4.0 
                 170 
                 1.1 
                 50 
                 270 
                 6.1 
                 6.08 
               
               
                 Example 48 
                 2.0 
                 115 
                 3.2 
                 110 
                 2.0 
                 115 
                 340 
                 7.2 
                 5.30 
               
               
                 Example 49 
                 2.1 
                 115 
                 3.2 
                 110 
                 2.1 
                 115 
                 340 
                 7.4 
                 5.47 
               
               
                 Example 50 
                 2.2 
                 115 
                 3.2 
                 110 
                 2.2 
                 115 
                 340 
                 7.6 
                 5.82 
               
               
                 Example 51 
                 2.1 
                 115 
                 4.0 
                 170 
                 2.1 
                 115 
                 400 
                 8.2 
                 5.87 
               
               
                 Example 52 
                 2.2 
                 115 
                 4.0 
                 170 
                 2.2 
                 115 
                 400 
                 8.5 
                 6.15 
               
               
                 Example 53 
                 2.3 
                 115 
                 4.0 
                 170 
                 2.3 
                 115 
                 400 
                 8.7 
                 6.60 
               
               
                 Example 54 
                 2.1 
                 115 
                 4.0 
                 170 
                 2.1 
                 115 
                 340 
                 8.2 
                 6.37 
               
               
                 Example 55 
                 2.2 
                 115 
                 4.0 
                 170 
                 2.2 
                 115 
                 340 
                 8.5 
                 6.79 
               
               
                 Example 56 
                 2.3 
                 115 
                 4.0 
                 170 
                 2.3 
                 115 
                 340 
                 8.7 
                 7.94 
               
               
                   
               
            
           
         
       
     
     The above descriptions are only preferred embodiments of the present invention. It should be noted that a number of improvements and modifications can be made by those skilled in the art without departing from the principles of the present invention, and these improvements and modifications should also be considered to be within the protection scope of the present invention.