Title of Invention

A PROCESS FOR PRODUCING A SANITARY NAPKIN

Abstract

This invention relates to a process for producing a sanitary napkin comprising the steps of cutting the industrial cellulosic waste as herein described, chemical treatment of the cut waste with a mixture of alkali followed by neutralization with an acid in water, washing the waste for removal of unreacted chemicals, hydro extraction of the washed waste, drying the waste obtained in step (d), opening of dried fibers in a fiber opening machine, forming the core from the fiber of step (f) into a web followed by sealing with a sheet at top and bottom and application of a release paper on the bottom side of the napkin.

Full Text

FIELD OF INVENTION This invention relates to a process for producing a sanitary napkin In particular, this invention relates to a sanitary napkin produced from modified industrial cellulosic waste PRIOR ART It is generally known that a sanitary napkin comprises an absorbent core having an upper sheet of a pervious material and a lower sheet of an impervious material Both the upper and lower sheets are sealed to the absorbent core to form the sanitary napkin Reference is made to particular to the absorbent core The known absorbent core was produced from wood pulp For this purpose, wood pulp is introduced into a grinder for breaking the pulp into small pieces In the same grinder and subsequent to breaking the pulp into small pieces, the cut pulp is subjected to the step of air carding/fluffing for opening of the fibers The open fibers are introduced into a web forming mold for formation of the core The core in the form of a continuous length is then sealed to the upper and lower sheets in a sealing unit, and where the upper and lower sheets are also as continuous sheets The formed napkin from the sealing unit is then fed to a cutting machine to cut the continuous length into sanitary napkins of required length A disadvantage of such a process is that it was continuous in nature, and thus the machinery occupied a substantial space Yet another disadvantage is that it employed wood pulp as a starting material, which results in deforestation Still another disadvantage is that the known process employed sophisticated equipment's/ machinery's which involved high infrastructure cost leading to higher initial investment cost OBJECTS OF THE INVENTION An object of this invention is to propose a process for producing a sanitary napkin, which is cost effective Another object of this invention is to propose a process for producing a sanitary napkin and having modified industrial cellulosic wastes as a starting material Still another object of this invention is to propose a process for producing a sanitary napkin, which is a batch process, which can be adopted in the rural backyards providing a source of income to the rural population Yet another object of this invention is to propose a process for the producing a sanitary napkin which is economical and does not require sophisticated machines Another object of this invention is to propose a process for producing a sanitary napkin, which consumes low energy A further object of this invention is to propose a process for producing a sanitary napkin, which involves machines that can be operated by unskilled laborer/rural population. STATEMENT OF INVENTION According to this invention there is provided a process for producing a sanitary napkin comprising the steps of:- a) cutting the industrial cellulosic waste as herein described, b) chemical treatment of the cut waste with a mixture of alkali followed by neutralization with an acid in water, c) washing the waste for removal of unreacted chemicals, d) hydro extraction of the washed waste, e) drying the waste obtained in step (d), f) opening of dried fibers in a fiber opening machine, g) forming the core from the fiber of step (f) into a web followed by sealing with a sheet at top and bottom and application of a release paper on the bottom side of the napkin. DETAILED DESCRIPTION OF THE INVENTION In accordance with this invention, the cut fibers are treated or soaked with a mixture of alkali. The alkali mixture comprises preferably each of 50% of sodium hydroxide and 50% of sodium carbonate. The alkali mixture also comprises sodium hydroxide, sodium biocarbonate and sodium carbonate in a ratio mentioned hereinafter. The alkali mixture is 2 to 8% preferably 2 to 4% in case of first combination and 20 to 30% in case of second combination. The chemical treatment is carried out with alkali mixture for a period of 10-30 minutes. The treated fibers are transferred to another tank filled with water wherein the fibers are neutralized with acid such as acetic acid and Hydrochloric acid mixed with the water in an amount of 5 to l0% The neutralized fibers are washed with water to remove any unreacted chemicals Prior to the chemical treatment, the waste available in different lengths are cut into small size, for example, 3 to 30 mm to increase the absorbency by capillary action A tow cutting machine may be used for this purpose The fibers thus obtained are wrapped in a Markin cloth and incorporated m a hydroextractor, which is run for 5 to 10 minutes so as to remove excess water from fibres This is followed by removal of the fibers, which are dned in sun or in an oven by spreading the fibres on trays in the oven The drying is earned out in the oven at 60°-100°C for 3-8 hours The dry fibers thus obtained are incorporated in fiber opening machine for opening of fibers, which is subjected to compression moulding in a compression moulding machine to form individual shaped web In accordance with one embodiment, the top and lower sheets are cut to size in a die cutter and then sealed in a sealing unit to the individual shaped webs wherein the bottom sheet is made of polyethylene and top sheet is hydrophihc non-woven polypropylene/polyethylene In accordance with another embodiment, the open fibers are taken into a web-carding machine to form the web of continuous length The web is cut to size and then sealed to the upper and lower sheets The sample thus obtained is applied with adhesive on the bottom side so as to fix a release paper thereon followed by packaging The degree of polymerization of the modified industrial cellulosic waste of the present invention is 300 to 450 However, the absorbency are imparted by the chemical treatment Further, objects and advantages of this invention will be more apparent from the ensuing examples, but which are not intended to imply any limitation on the scope of the invention A Example No Alkali Mixture (50 50) Absorbency (S) (Sodium hydroxide and sodium carbonate) Ex-1 2 >30 Ex-2 3 6-7 Ex-3 4 5-6 B Example No Alkali Mixture (35 15 50) Absorbency (S) (Sodium hydroxide , Sodium bicarbonate and sodium carbonate) Ex-1 10 >30 Ex-2 20 >10 Ex-3 30 4-5 C Example No Alkali Mixture (35 30 35) Absorbency (S) (Sodium hydroxide , Sodium bicarbonate and sodium carbonate) Ex-1 15 >35 Ex-2 25 >15 Ex-3 35 7-8 It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims. 1. A process for producing a sanitary napkin comprising the steps of:- a) cutting the industrial cellulosic waste as herein described, b) chcmical trcatmcnt of thc cut wastc with a mixturc of alkali followed by neutralization with an acid in water, c) washing the waste for removal of unreacted chemicals, d) hydro extraction of the washed waste, c) drying thc wastc obtained in step (d), 1) opening of dried fibers in a fiber opening machine, g) forming the core from the fiber of step ( f ) into a web followed by sealing with a sheet at top and bottom and application of a release paper on the bottom side of the napkin. 2. A process as claimed in claim 1 wherein the chemical treatment is carried out with alkali mixture in the range of 2 to 8% preferably 2 to 4% when the alkali mixture comprises Sodium hydroxide and Sodium carbonate and 20 to 35% when the alkali mixture comprises Sodium hydroxide, Sodium carbonatc and Sodium biocarbonatc. 3. A process as claimed in claim 1 or 2 wherein the step of drying is carried out at a temperature of 90" - 100°C. 4. A proccss as claimed in claim 1 wherein the step of drying is carried out for 3 to 5 hours. 5. A proccss as claimed in claim 1 wherein the alkali mixture comprises 50% each of sodium hydroxide and sodium carbonate. 6. A process for producing a sanitary napkin as claimed in any one of the preceding claims wherein the hydroextractiuon of the waste is carried out for 5- 10 minutes. 7. A process for producing a sanitary napkin as claimed in any one of the preceding claims wherein the web is prepared by compression moulding machine or web carding machine. 8. A process for producing a sanitary napkin as claimed in any one of the preceding claims wherein the top sheet is non-woven polypropylene/polycthylene and bottom sheet is polyethylene. 9. A process for producing a sanitary napkin as claimed in any one of the preceding claims wherein concentration of acetic acid is 5-10% solution for neutralization.

Documents:

643-DEL-2005-Abstract-(16-03-2011).pdf

643-del-2005-abstract.pdf

643-del-2005-Claims-(13-03-2013).pdf

643-DEL-2005-Claims-(16-03-2011).pdf

643-del-2005-claims.pdf

643-DEL-2005-Correspondence Others-(16-03-2011).pdf

643-del-2005-Correspondence-Others-(13-03-2013).pdf

643-del-2005-correspondence-others.pdf

643-del-2005-correspondence-po.pdf

643-DEL-2005-Description (Complete)-(16-03-2011).pdf

643-del-2005-description (complete).pdf

643-del-2005-description (provisional).pdf

643-DEL-2005-Form-1-(16-03-2011).pdf

643-del-2005-form-1.pdf

643-del-2005-form-18.pdf

643-del-2005-form-2.pdf

643-del-2005-form-5.pdf

643-DEL-2005-GPA-(16-03-2011).pdf

643-DEL-2005-Petition 137-(16-03-2011).pdf