Method of Improving Re-Closure of Oxidative Hair Colorant Sachet with Foldable Re-Closure Device

Abstract

The present invention relates to a method of maintaining chemical reactivity of an oxidative hair colorant in an opened flexible sachet including a reclosure element. The quality of the re-closure will strongly influence how the hair colorant will perform when using it as intended. The method according to the present invention ensures maintaining chemical reactivity by improving the quality of the re-closure by intuitively inducing safe and tight re-closure by users of such hair colorant. This is achieved by providing the sachet to the user in a configuration already in its re-closure position, while the sachet has not been opened yet.

What is claimed is: 
     
         1 . Method of maintaining chemical reactivity of an oxidative hair dye component while being stored in an opened flexible sachet by increasing the user compliance with the re-closure step of a usage regime of said oxidative hair dye component, said regime comprising the steps of
 a. evaluating suitability to use said oxidative hair dye component for coloring the hair of a person without causing an unacceptable skin reaction by opening said flexible sachet and extracting a minor amount of said oxidative hair dye component from the opened flexible sachet for applying said minor amount of oxidative hair dye component to the skin of said person,   b. closing said sachet to prevent oxidation reaction of said oxidative hair dye component due to exposure to air oxygen through said opening,   c. allowing said oxidative hair dye component to remain on said skin of said person for a predetermined amount of exposure time and removing the oxidative hair dye component from said skin,   d. after a predetermined reaction time visually inspecting the skin of said person where said oxidative hair dye component had been applied and deciding whether said oxidative hair dye component is causing an unacceptable skin reaction or not   e. using said oxidative hair dye component to color the hair of said person, provided no unacceptable skin reaction was caused by said oxidative hair dye component.   Said method comprising the steps of
 I) providing said oxidative hair dye component in said flexible sachet, said flexible sachet having a laminate structure for storing said oxidative hair dye component and said sachet comprising:
 a reservoir with an internal volume for storing said oxidative hair dye component, having a reservoir height and a reservoir width, 
 a pouring spout being in fluid communication with the internal volume and having a dispensing end for dispensing said oxidative hair dye component, 
 the pouring spout projecting from an upper side of the reservoir and having an elongated shape with a width being smaller than the width of the reservoir, 
 a removable tear tab at the dispensing end, said tab sealing the sachet prior to opening said sachet, 
 the pouring spout comprises a re-closure element for reclosing the dispensing end once the tear tab has been removed, the re-closure element provides capability of reclosing by folding a portion of said pouring spout onto itself and said re-closure element essentially keeps said folded pouring spout in said folded position either by having a stiffness being greater than the stiffness of the laminate structure or by mechanical snap and seal means or by mechanical hook and loop means and the re-closure element thereby reducing or preventing premature oxidation of said oxidative hair dye component in said sachet after opening, 
 said pouring spout being folded onto itself into a re-closed position already as provided prior to opening said sachet, 
 
 II) unfolding said re-closure element from said folded re-closure position into an extended position for opening and extracting said amount of said oxidative hair dye component from said sachet, thereby providing experiential guidance on the re-closed position of said sachet and thereby increasing compliance with the re-closure requirement. 
   
     
     
         2 . The method according to  claim 1 , having a third subsequent step
 III) reclosing said sachet with the re-closure element by folding it onto itself into a re-closed position as it was provided prior to opening said sachet.   
     
     
         3 . The method according to  claim 1 ,
 wherein said re-closure element comprises an element selected from a metal strip, plastic strip, band, and/or an additional rigid layer, which layer is attached to or inserted in the laminate structure.   
     
     
         4 . The method according to  claim 3  wherein the re-closure element is a wire tie. 
     
     
         5 . The method according to  claim 1 ,
 wherein said exposure time is at least as long as the recommended usage time of said oxidative hair dye component.   
     
     
         6 . The method according to  claim 1  wherein said exposure time is at least 10 minutes. 
     
     
         7 . The method according to  claim 1  wherein said reaction time is at least 24 hours. 
     
     
         8 . The method according to  claim 1 ,
 wherein said minor amount of said oxidative hair colorant is less than 10% by weight of the total amount of said oxidative hair dye component in said sachet prior to opening said sachet.   
     
     
         9 . The method according to  claim 8 ,
 wherein said minor amount of said oxidative hair colorant is 5% or less by weight of the total amount of said oxidative hair dye component in said sachet prior to opening said sachet.   
     
     
         10 . The method according to  claim 1 ,
 wherein said pouring spout is integrally formed with said reservoir.   
     
     
         11 . The method according to  claim 10   wherein said tear tab is integrally formed with said pouring spout.   
     
     
         12 . The method according to  claim 1   wherein said flexible sachet comprises a pre-defined tearing line between the tear tab and the dispensing end of the pouring spout, along which the tear tab is torn when the sachet is opened.   
     
     
         13 . The method according to  claim 12   wherein said tear tab is completely torn off from said sachet.   
     
     
         14 . The method according to  claim 1 ,
 wherein said pouring spout comprises at its inner perimeter at least one flow restrictor for restricting the flow of said hair dye component when it dispenses.   
     
     
         15 . The method according to  claim 14 ,
 wherein said at least one flow restrictor is formed as a bulge projecting inside the pouring spout.   
     
     
         16 . The method according to  claim 1 ,
 wherein said reservoir width is from 47% to 53% of the reservoir height.   
     
     
         17 . The method according to  claim 1 ,
 wherein said reservoir height is between 110 and 160 mm.   
     
     
         18 . The method according to  claim 1 ,
 wherein said reservoir width is between 45 and 60 mm.   
     
     
         19 . The method according to  claim 1 ,
 wherein said width of said pouring spout is 30% or less of the width of said reservoir.   
     
     
         20 . A flexible sachet for use in the method according to  claim 1 ,
 said flexible sachet having a laminate structure for storing a hair dye component and said sachet comprising:
 a reservoir with an internal volume for storing said oxidative hair dye component, having a reservoir height and a reservoir width, 
 a pouring spout being in fluid communication with the internal volume and having a dispensing end for dispensing said oxidative hair dye component, 
 the pouring spout projecting from an upper side of the reservoir and having an elongated shape with a width being smaller than the width of the reservoir, 
 a removable tear tab at the dispensing end, said tab sealing the sachet prior to opening said sachet, 
 the pouring spout comprises a re-closure element for reclosing the dispensing end once the tear tab has been removed, the re-closure element having a stiffness being greater than the stiffness of the laminate structure and the re-closure element providing capability of reclosing by folding a portion of said pouring spout onto itself and said re-closure element essentially keeping said folded pouring spout in said folded position thereby reducing or preventing premature oxidation of said oxidative hair dye component in said sachet after opening, 
 said pouring spout being folded onto itself into a re-closed position already as provided prior to opening said sachet.