Fadable Multifunctional Monofilament Having a Core-Shell Structure

Abstract

The present invention relates to a fadable multifunctional monofilament. More particularly, the present invention relates to a fadable multifunctional monofilament having a core-shell structure comprising an active substance(s) or a functional filler(s). The present invention also relates to a method for preparing the monofilament material, and a use of the monofilament material in a brush material such as a toothbrush.

1 . A fadable multifunctional monofilament having a core-shell structure, wherein the core layer of the multifunctional monofilament comprises an active substance(s) or a functional filler(s), and the multifunctional monofilament as a whole comprises a dye(s), and a fadable effect is realized by means of gradual release of the dye during use of the multifunctional monofilament; wherein the thickness of the shell layer of the multifunctional monofilament is greater than or equal to 10 μm, preferably greater than or equal to 20 μm. 
     
     
         2 . The multifunctional monofilament according to  claim 1 , wherein the diameter of the multifunctional monofilament is from 100 μm to 254 μm, and the thickness of the shell layer is from 20 μm to 100 μm. 
     
     
         3 . The multifunctional monofilament according to  claim 1 , wherein the active substance(s) contained in the multifunctional monofilament comprise(s) one or more of the followings: NaF, tea polyphenol, Azadirachta indica saponin, and clove oil. 
     
     
         4 . The multifunctional monofilament according to  claim 1 , wherein the functional filler(s) contained in the multifunctional monofilament comprise(s) one or more of the followings: aluminum flakes and mica flakes. 
     
     
         5 . The multifunctional monofilament according to  claim 1 , wherein the proportion of the active substance or the functional filler contained in the multifunctional monofilament is from 0.2 wt % to 10 wt %, based on the total weight of the multifunctional monofilament. 
     
     
         6 . The multifunctional monofilament according to  claim 1 , wherein the shell layer and the core layer of the multifunctional monofilament are composed of a material selected from the group consisting of nylon, polyester, or a combination thereof. 
     
     
         7 . The multifunctional monofilament according to  claim 1 , wherein the dye(s) is/are food grade dye(s). 
     
     
         8 . The multifunctional monofilament according to  claim 7 , wherein the food grade dye(s) comprise(s) an acidic water soluble/disperse dyes, and the water soluble/disperse dyes comprise: indigoid dyes, plant-based natural dyes, methylene blues, anthraquinone dyes. 
     
     
         9 . The multifunctional monofilament according to  claim 8 , wherein the indigoid dyes comprise indigo blue, indigo red, indigo violet, or a combination thereof in any ratio. 
     
     
         10 . The multifunctional monofilament according to  claim 8 , wherein the disperse dyes comprise disperse orange, disperse blue, disperse yellow, disperse red; or disperse black, disperse green or disperse violet obtained by any ratio combination of disperse orange, disperse blue, disperse yellow, and disperse red thereof. 
     
     
         11 . The multifunctional monofilament according to  claim 8 , wherein the plant-based natural dyes comprise curcumin, anthocyanin, shikonin, alizarin red, betalain, and the like. 
     
     
         12 . The multifunctional monofilament according to  claim 1 , wherein the shell layer and/or the core layer in the multifunctional monofilament further comprises an additive(s) selected from the group consisting of antioxidants, light stabilizers, antistatic agents, lubricants, plasticizers, conventional fillers, and antibacterial agents. 
     
     
         13 . A process for preparing the multifunctional monofilament according to  claim 1 , comprising the steps of:
 1) adding a base resin, an active substance(s) or a functional filler(s), and optionally other additives to extruder A to provide a melt for forming a core layer of a monofilament having a core-shell structure; and adding the same or different base resin and optionally other additives to extruder B to provide a melt for forming a shell layer of a monofilament having a core-shell structure;   2) converging the above two melts in a co-extrusion spinning pack, after extruding from a spinneret hole(s), cooling and solidifying the converged melt and then performing heat drawing and heat setting to obtain a multifunctional monofilament containing an active substance(s) or a functional filler(s) and having the core-shell structure;   3) dyeing the multifunctional monofilament with the core-shell structure by a dyeing process;   4) optionally performing post-treatment after the dyeing treatment to obtain a final fadable multifunctional monofilament having a core-shell structure.   
     
     
         14 . A brush made of the multifunctional monofilament according to  claim 1 . 
     
     
         15 . The brush of  claim 14 , wherein the brush is a toothbrush.