WO2022264070A1

WO2022264070A1 - Disposable absorbent product and a process for its preparation

Info

Publication number: WO2022264070A1
Application number: PCT/IB2022/055561
Authority: WO
Inventors: Sarika Onkar Pathak
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-06-16
Filing date: 2022-06-16
Publication date: 2022-12-22
Anticipated expiration: 2023-12-16

Abstract

The present disclosure relates to disposable absorbent product and a process for its preparation. The disposable absorbent product comprises at least one liquid permeable top layer of a first predetermined thickness, at least one absorbent layer of a second predetermined thickness, and at least one liquid non-permeable bottom layer of a third predetermined thickness. The absorbent layer is disposed and bonded between the liquid permeable top layer and the liquid non-permeable bottom layer. The top layer and the bottom layer are at least partially soluble in water and the absorbent layer is at least partially dispersible in water. The disposable absorbent product of the present disclosure is plastic free, bleach free, chlorine free, biodegradable, compostable, and hence safer and environment friendly.

Description

DISPOSABLE ABSORBENT PRODUCT AND A PROCESS FOR ITS PREPARATION

FIELD

The present disclosure relates to a disposable absorbent product and a process for its preparation.

DEFINITIONS

As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicates otherwise. Absorbent disposable product: The term “absorbent disposable product” refers to the products designed to absorb excreted body fluids at various stages of a consumer's life and is popularly known as baby diaper, adult diaper, napkin, sanitary pad, tampon, panty liner and the like.

Flexing resistance: The term “flexing resistance” also known as “flex resistance” and “flex durability” refers to a measure of toughness of a plastic film, specifically the resistance of the plastic film to pin holing when subjected to flexing abuse.

BACKGROUND

The background information herein below relates to the present disclosure but is not necessarily prior art. Conventionally available disposable diapers, tampons, sanitary napkins and the like are made of synthetic disposable materials and are not environment friendly. The plastic used in these products is non-biodegradable. Conventional disposable diapers and sanitary napkins are not flushable and they end up in landfill or incinerated in some cases causing land pollution and some end up in water bodies causing water pollution. Decomposition of the diapers release methane gas into the air. High concentrations of the methane gas can be explosive and flammable· Methane is also dangerous to breathe in as it replaces oxygen.

A single sanitary pad or diaper takes 500 to 800 years to decompose and can lead to health and environmental hazards. The millions of ton of untreated waste added to landfills each year through plastic diapers, sanitary napkins, tampons and the like contaminates the soil and the groundwater.

Further, the conventional materials used for the diapers and the sanitary napkins are bleached with chlorine for getting white color and the absorbent powder used in it is petroleum based super absorbent polymer (sodium poly acrylate). The bleaching process used on diapers and sanitary napkins creates dioxins as a by-product. Dioxins are highly toxic, carcinogenic and linked to long-term health problems.

Still further, “flush ability” of the diapers, sanitary napkins, tampons and the like have become a critical issue for wastewater treatment facilities as the disposed diapers and sanitary napkins choke the piping and pumps at the treatment plants. As the conventional disposable diapers and sanitary napkins are not flushable, they mean to end up in landfill causing the land pollution and some end up in water bodies causing the water pollution.

Another option for the disposal of sanitary napkins is incineration. Incinerator reduces the sanitary waste to sterile ash that can be used as manure or can be flushed down the toilet. However, this method also leads to serious health hazards since it produces harmful gaseous emissions such as dioxin, furan and the like in significant amounts. These gases may cause serious health problems such as cancer, immune system damage, reproductive health related diseases and the like. The ash produced during incineration process is also a potential health hazard since it contains high concentration of heavy metals such as lead, cadmium, copper and the like. Other pollutants of concern from incinerators include halogenated hydrocarbons, acid gases that are precursors of acid rain, particulates responsible for lung infections and the like. Incinerators also had demerits like smell issue, high recurring, and setup cost. In addition, incinerators consume very high energy.

The environmental and health hazards caused by discarding such disposable materials, and increasing consumer demand for greener or more eco-friendly products has necessitated developing biodegradable products with minimal environmental footprint through various levels of the supply chain, including raw materials, packaging and the like.

Therefore, there is felt a need to provide an alternative disposable absorbent product which obviates the drawbacks mentioned herein above or at least provides an alternative solution. OBJECTS

Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.

An object of the present disclosure is to ameliorate one or more problems of the prior art or to at least provide a useful alternative.

Another object of the present disclosure is to provide a disposable absorbent product.

Yet another object of the present disclosure is to provide a disposable absorbent product which is soluble in hot water.

Still another object of the present disclosure is to provide a disposable absorbent product that is biodegraded with the micro-organisms present in water and thus, eliminating all environmental footprints.

Still another object of the present disclosure is to provide a disposable absorbent product that is plastic free and chemical free.

Yet another object of the present disclosure is to provide a disposable absorbent product that is safe and skin friendly.

Still another object of the present disclosure is to provide a simple and an efficient process for the preparation of a disposable absorbent product.

Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure. SUMMARY

The present disclosure relates to a disposable absorbent product. The disposable absorbent product comprises at least one liquid permeable top layer of a first predetermined thickness, at least one absorbent layer of a second predetermined thickness, and at least one liquid non- permeable bottom layer of a third predetermined thickness. The absorbent layer is disposed and bonded between the liquid permeable top layer and the liquid non-permeable bottom layer. The top layer and the bottom layer are at least partially soluble in water and the absorbent layer is at least partially dispersible in water. The present disclosure also relates to a process for the preparation of a disposable absorbent product. The process comprises the steps of: (i) disposing at least one absorbent layer of a first predetermined thickness between at least one liquid permeable top layer of a second predetermined thickness and at least one liquid non-permeable bottom layer of a third predetermined thickness to obtain a stack; and (ii) bonding the stack together by using at least one of method selected from hot water soluble stitching, water soluble gum, cold water soluble polyvinyl alcohol liquid gel, hot melting and ultrasonic welding to obtain the disposable absorbent product.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING The present disclosure will now be described with the help of the accompanying drawing, in which:

Figure 1 illustrates the analysis of disposable absorbent product (sanitary napkin) of the present disclosure; and

Figure 2 illustrates the dry mass of insoluble part of the disposable absorbent product (sanitary napkin) of the present disclosure after dissolving in hot water.

DETAILED DESCRIPTION

Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.

Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed. Conventional diapers, sanitary napkins, tampons and the like are not environment friendly. The plastic used in these products is non-biodegradable. Conventional disposable diapers and sanitary napkins are not flushable and they end up in landfill or incinerated in some cases causing land pollution and some end up in water bodies causing water pollution. Decomposition of the diapers release methane gas into the air. High concentrations of the gas can be explosive and flammable. Methane is also dangerous to breathe in as it replaces oxygen.

Considering environmental and health hazards and increasing consumer demand for greener and more eco-friendly products, it has become necessary to develop hot water soluble disposable and biodegradable products. The present disclosure relates to a disposable absorbent product and a process for its preparation.

In an aspect, the present disclosure provides a disposable absorbent product. The disposable absorbent product comprises at least one liquid permeable top layer of a first predetermined thickness, at least one absorbent layer of a second predetermined thickness, and at least one liquid non-permeable bottom layer of a third predetermined thickness. The absorbent layer is disposed and bonded between the liquid permeable top layer and the liquid non-permeable bottom layer.

The top layer and the bottom layer are at least partially soluble in water and the absorbent layer is at least partially dispersible in water. In one embodiment, the top layer and the bottom layer are at least partially soluble in water below its boiling point and the absorbent layer is at least partially dispersible in water below its boiling point.

In accordance with the embodiment of the present disclosure, the top layer and the bottom layer are at least partially soluble in water at a temperature in the range of 40 °C to 100 °C and the absorbent layer is at least partially dispersible in water at a temperature in the range of 40 °C to 100 °C.

In another embodiment, the top layer and the bottom layer start solubilizing in water above the normal body temperature i.e. above 40 °C and does not disintegrate in water below room temperature.

Some portion of the absorbent layer is soluble in water at a temperature in the range of 40 °C to 100 °C.

In a preferred embodiment, the top layer and the bottom layer are completely soluble in water at 90 °C and the absorbent layer is completely dispersible in water at 90 °C. In accordance with the present disclosure, the liquid permeable top layer is a sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

In accordance with an embodiment of the present disclosure, the liquid permeable top layer is made up of non-woven fibers of polyvinyl alcohol. In accordance with the present disclosure, the first predetermined thickness is in the range of 20 micron to 60 micron. In an exemplary embodiment, the first predetermined thickness is 30 micron.

In accordance with the present disclosure, the absorbent layer is a super-absorbent polymer layer made up of a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid; wherein the material is layered and sandwiched between the biodegradable tissue paper layers.

The tissue paper is easily disintegrable in hot water and normal water as well. In an embodiment of the present disclosure, the super-absorbent polymer layer (SAP sheet) combined with tissue paper layer is used in an ultra-thin foldable sanitary napkin.

In accordance with an embodiment of the present disclosure, the hot water soluble fibers are mixed with biodegradable absorbent polymer which is chemical free and toxic free. In accordance with the present disclosure, the hot water soluble fibers are selected from polyvinyl alcohol and polyvinyl pyrrolidone.

In accordance with the present disclosure, the plant based biodegradable absorbent powder is selected from the group consisting of starch, polysaccharide, sodium alginate, carboxymethyl cellulose, xanthan gel powder, gelatin powder, corn starch, karaya gum powder, guar gum powder, dry aloe vera powder, tamarind seed powder and mango seed powder.

In accordance with the present disclosure, the biodegradable pulp is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse. The biodegradable pulp used is in the form of adsorbent powder and is prepared from banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

The biodegradable pulp of the present disclosure provide good absorption, softness, comfort and has anti-bacterial properties.

In accordance with the present disclosure, the biodegradable air-laid is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

In accordance with an embodiment of the present disclosure, the absorbent layer is a mixture of biodegradable pulp, plant based biodegradable absorbent powder and biodegradable air- laid sheet. In accordance with another embodiment of the present disclosure, hot water soluble fibers are mixed with a biodegradable absorbent polymer. The hot water soluble fibers are used along with the biodegradable pulp to add more absorption and equal spread of liquid across the absorbent layer of the disposable absorbent product. In accordance with the present disclosure, the second predetermined thickness is in the range of 4 m to 8 mm (120 gsm to 250 gsm). In an exemplary embodiment, the second predetermined thickness is 5 mm (150 gsm).

In accordance with the present disclosure, the non-permeable bottom layer is a non- permeable sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone .

In accordance with the present disclosure, the third predetermined thickness is in the range of 20 micron to 60 micron. In an exemplary embodiment, the third predetermined thickness is 35 micron. In accordance with the present disclosure, at least one of the layers can comprise natural and synthetic antimicrobial agents.

The disposable absorbent product of the present disclosure is packaged with a polyvinyl alcohol film having a thickness in the range of 20 micron to 60 micron.

In an embodiment, a single sanitary napkin (disposable absorbent product) is packaged with the polyvinyl alcohol film having a thickness in the range of 20 micron to 60 micron.

In another embodiment, a stack of sanitary napkins (disposable absorbent products) is packaged with the polyvinyl alcohol film having a thickness in the range of 20 micron to 60 micron.

In accordance with an embodiment of the present disclosure, the disposable absorbent product is majorly made up of polyvinyl alcohol and the materials made therefrom. Polyvinyl alcohol is a water soluble synthetic polymer. Polyvinyl alcohol is colorless and odorless and can be easily degraded by microorganisms as well as enzymes. In soil, the polyvinyl alcohol is easily decomposed by microorganisms and eventually degrades into water and carbon dioxide (1¾0 and C(¾). At the same time, it can decompose in a compost site under composting conditions. Polyvinyl alcohol is used in a variety of medical applications because of its biocompatibility, low tendency for protein adhesion and low toxicity. PVA has high tensile strength and flexibility, as well as high oxygen and aroma barrier properties. The polyvinyl alcohol has a property to be soluble at a temperature in the range of 20 °C to 100 °C. Polyvinyl alcohol film has good tenacity, biaxial tension-strength and anti-tearing strength that ranks high among all kinds of films, flexing resistance is 10 times to other films. It has excellent strength, weathering resistance and long service life.

Polyvinyl alcohol film has an excellent gas barrier to oxygen, nitrogen, hydrogen, helium, argon, carbonic acid gas and the like, when the humidity is low. However, the polyvinyl alcohol permits penetration of moisture and N¾. Moreover, it has an excellent fragrance preservation of the contents and can keep the disposable absorbent products moist and fresh as well.

The disposable absorbent product has good heat sealability and adhesiveness to hold all layers together along with fluid.

In accordance with the present disclosure, the disposable absorbent product is selected from baby diaper, adult diaper, sanitary napkin, panty liner, tampon, absorbent bed for patients and the like.

In an embodiment of the present disclosure, the disposable absorbent product is a sanitary napkin that is soluble in hot water.

In another embodiment of the present disclosure, the disposable absorbent product is the diaper that is soluble in hot water.

In accordance with the second embodiment of the present disclosure, the diaper comprises another layer of soft hot water soluble non-woven sheet to get a soft pant like feeling. In an embodiment of the present disclosure, the diaper is a flat/tape diaper or a pant diaper.

The pant diaper is made of soft and porous material (allowing air to pass through), so as not to restrict air flow to baby’s bottoms. The stretchable part of the pant diaper is made of water soluble polyvinyl alcohol stretchable flexible lace.

In accordance with the present disclosure, the diapers have wetness indicator lines to know when the diaper is wet. The diapers further comprise a reusable sensor based wetness indicator which sends a signal to parent’s mobile app when the diaper is wet.

The disposable absorbent product of the present disclosure needs to be stored at a room temperature and dry area (moisture free area) without being handy to babies. After using the disposable absorbent product of the present disclosure, the disposable absorbent product can be dissolved in hot water having a temperature in the range of 40 °C to 100 °C and discarded. The hot water soluble material along with the natural degradable cellulose can be then carried away through bathroom pipes to sewage and biodegraded in a conventional landfill as well as marine conditions such as fresh, brackish or salt water. The hot water insoluble material is biodegradable.

Menstruation and menstrual practices still face many social, cultural, and religious restrictions which are a big barrier in the path of menstrual hygiene management. In many parts of the country, especially in rural areas, girls are not prepared and aware about menstruation and hence, they face many difficulties and challenges at home, schools, and work places. Girls and women have very less or no knowledge about reproductive tract infections caused due to ignorance of personal hygiene during menstruation time. Women dispose of menstrual products in domestic wastes and in public toilets and they flush them in the toilets without knowing the consequences of choking. So, there should be a need to educate and make them aware about the environmental pollution.

Apart from environmental impact, the non-biodegradable sanitary napkins are also linked to health issues in women. Most of the non-biodegradable sanitary napkins contain volatile organic compounds (VOCs), phthalates, and other harmful compounds which can cause conditions ranging from nausea, fatigue and even cancer. Short term exposure to VOCs can lead to irritation of the eyes and respiratory tract, visual disorders and memory problems. Long term exposure can induce nausea, fatigue, loss of coordination, damage to the liver, kidneys and central nervous system and can also cause cancer.

The disposable absorbent products of the present disclosure are not required to be thrown away in garbage or landfills after use. Hence, it does not affect the health and hygiene of the waste pickers.

The present disclosure provides the disposable absorbent product that is eco-friendly since it is plastic free, biodegradable and compostable.

The disposable absorbent product of the present disclosure are bleach free, chlorine free and chemical free. The sanitary napkins (disposable absorbent product) of the present disclosure has the following advantages over the conventional sanitary napkins:

^■ as the sanitary napkin of the present disclosure is soluble in hot water, it can be disposed of in the washroom itself and hence, the women would have no worry of disposing the sanitary napkins (wrapping, looking for dispose bin, carrying paper to wrap and the like);

^■ the environment would have a huge impact in terms of reducing time of waste (sanitary napkin waste) staying in the environment from 800 years to few seconds, in terms of reducing plastic pollution i.e., no carcinogenic pollution by burning the pads;

^■ the waste pickers would no more have to carry out the segregation of menstrual waste manually, thus, improving health and dignity;

^■ the corporates/ Institutes would not require to pay huge amounts every month just to get rid of the waste from their campuses; and

^■ there will be no clogging in the drainage system due to plastic/polymer in sanitary napkins.

In another aspect, the present disclosure provides a process for the preparation of a disposable absorbent product.

Initially, at least one absorbent layer of a first predetermined thickness is disposed between at least one liquid permeable top layer of a second predetermined thickness and at least one liquid non-permeable bottom layer of a third predetermined thickness to obtain a stack.

In accordance with the present disclosure, the liquid permeable top layer is a sheet made up of a material selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone.

In accordance with the present disclosure, the first predetermined thickness is in the range of 20 micron to 60 micron.

In accordance with the present disclosure, the absorbent layer is a super-absorbent polymer layer made up of a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid.

In accordance with an embodiment of the present disclosure, a hot water soluble fiber is mixed with a non-biodegradable absorbent polymer. In accordance with the present disclosure, the hot water soluble fiber is selected from polyvinyl alcohol and polyvinyl pyrrolidone.

In accordance with the present disclosure, the biodegradable pulp is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse In accordance with the present disclosure, the biodegradable air-laid is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

In accordance with the present disclosure, the second predetermined thickness is in the range of 4 mm to 8 mm (120 gsm to 250 gsm). In accordance with the present disclosure, the non-permeable bottom layer is a non- permeable sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

In accordance with the present disclosure, the third predetermined thickness is in the range of 20 micron to 60 micron. The stack is bonded together by using at least one of method selected from hot water soluble stitching, water soluble gum, cold water soluble polyvinyl alcohol liquid gel, hot melting and ultrasonic welding to obtain the disposable absorbent product.

In accordance with the present disclosure, the absorbent layer is prepared by pressing or rolling a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid followed by sandwiching between biodegradable tissue paper layers.

In accordance with an embodiment of the present disclosure, the absorbent layer is prepared by manually pressing the pulp layer in the form of a cake. In accordance with another embodiment of the present disclosure, the absorbent layer is prepared by machine pressing to form a roll or a sheet. In accordance with still another embodiment of the present disclosure, the absorbent layer is prepared in the form of a rill for easy and fast production.

The top layer and the bottom layer are at least partially soluble in water and the absorbent layer is at least partially dispersible in water. The top layer and the bottom layer are completely soluble in water at 90 °C and the absorbent layer is completely dispersible in water at 90 °C. This property helps to keep the product intact till its storage and application at a normal temperature.

In accordance with the present disclosure, the disposable absorbent product is at least partially dissolved in hot water at a temperature in the range of 40 °C to 100 °C in a time period in the range of 30 seconds to 120 seconds.

In an embodiment of the present disclosure, the disposable absorbent product is at least partially dissolved in hot water within a time period in the range of 30 seconds to 40 seconds when the temperature of hot water is in the range of 80 °C to 100 °C. In another embodiment of the present disclosure, the disposable absorbent product is at least partially dissolved in hot water within a time period in the range of 40 seconds to 60 seconds when the temperature of hot water is in the range of 50 °C to 80 °C.

The time required for the dissolution of the absorbent product is directly proportional to the thickness of the permeable top layer and the non-permeable bottom layer of the disposable absorbent product and temperature of water.

The disposable absorbent product of the present disclosure is free of artificial fragrance and odour neutralizer. These artificial fragrance and odour neutralizer may cause skin irritation and allergy, and these may enters the blood stream causing the side effects. In accordance with an embodiment of the present disclosure, natural fragrances such as herbal or chemical fragrances can be used in the disposable absorbent product.

The disposable absorbent product of the present disclosure does not utilize rayon, which is cheaper than cotton and help enhancing the absorption capacity of the absorbent products. However, the rayon based absorbent products contain dioxin from the bleaching process. The disposable adsorbent product of the present disclosure has good anti-static property. The layers of disposable adsorbent product has lots of hydroxyl group and it does not take charges. The disposable adsorbent product is different from the film that is made from the other synthetic resins and it has the same antistatic properties of cellophane. The packing of the disposable adsorbent product with polyvinyl alcohol film keeps the product dust-free.

The disposable absorbent product of the present disclosure has polyvinyl alcohol film that has good tenacity, biaxial tension-strength, anti-tearing strength, flexing resistance, and ranks high among all the films. The disposable absorbent product has excellent weathering resistance and long service life. In still another aspect, the present disclosure provides a composition for making the disposable product. The composition comprises: a. at least one liquid permeable top layer having a thickness in the range of 20 micron to 60 micron, wherein the top layer is a sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone; b. at least one absorbent layer having a thickness in the range of 4 mm to 8 mm, wherein the absorbent layer is a super-absorbent polymer layer made up of a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid; and c. at least one liquid non-permeable bottom layer having a thickness in the range of 20 micron to 60 micron, wherein the bottom layer is a non-permeable film made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

The hot water soluble fiber is selected from polyvinyl alcohol and polyvinyl pyrrolidone. The plant based biodegradable absorbent powder is selected from the group consisting of starch, polysaccharide, sodium alginate, carboxymethyl cellulose, xanthan gel powder, gelatin powder, corn starch, karaya gum powder, guar gum powder, dry aloe vera powder, tamarind seed powder and mango seed powder. The biodegradable pulp is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

The biodegradable air-laid is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

In an embodiment of the present disclosure, the material selected from hot water soluble fiber, the plant based biodegradable absorbent powder, the biodegradable pulp and the biodegradable air-laid are layered and sandwiched between biodegradable tissue paper layers. The disposable product is selected from baby diaper, adult diaper, sanitary napkin, panty liner, tampon and absorbent bed.

The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.

The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to the industrial scale.

Experimental details:

Experiment 1: Process for the preparation of disposable absorbent product

Example 1: Process for the preparation of sanitary napkin in accordance with the present disclosure

A liquid permeable top layer was prepared by laying two layers made up of non- woven fibers of polyvinyl alcohol having thickness of 30 micron. Pine wood pulp was laid and manually pressed on layers of tissue paper (wrap) to obtain the absorbent layer having thickness of 150 gsm (5 mm).

A liquid non-permeable bottom layer of 35 micron was prepared by laying two non- permeable films of polyvinyl alcohol. The absorbent layer was disposed between the liquid permeable top layer and non-permeable bottom layer to obtain a stack. The stack was then bonded together by using a combination of water soluble gum hot melting and ultrasonic welding method.

Example 2 to 10: Sanitary napkins were prepared by following the same process as in Example 1 by using different absorbent materials with varying thickness of the absorbent layer as given in Table 1 below.

Table 1: Various absorbent materials with varying thickness of the absorbent layer and the absorbance capacity of the Sanitary napkins prepared in Examples 2 to 10

Experiment 2: Dissolution of sanitary napkin of example 1 in hot water

A sanitary napkin was prepared as per the process of example 1, and allowed to dissolve in water at 90 °C. Table 2 discloses the analysis of the sanitary napkin. Table 2: Analysis of sanitary napkin of example 1 (see figure 1)

It was observed that sanitary napkin was disintegrated, dispersed in water and some portion of it also dissolved in water in 1 minute and a flushable slurry was formed which could be discarded to sewage (Figure 2). Further, at any temperature above 60 °C, the disposable absorbent product gets dissolved and disintegrated into small pieces to form a slurry and the slurry can be flushed away.

Experiment 3: Microbial testing of the sanitary napkin prepared in accordance with the present disclosure

The microbial testing was performed on 7 units of the sanitary napkins before exposing to the UV light. Table 3 shows the microbial analysis of sanitary napkin before exposure to UV light.

Table 3: Microbial analysis of sanitary napkin before exposure to UV light

No pathogens were detected on the sanitary napkin before exposure to UV light, and were considered to be safe for use.

The microbial testing was performed on the sanitary napkins after exposing to the UV light (254 nm for 30 min). Table 4 shows the microbial analysis of sanitary napkin after exposure to UV light.

Table 4: Microbial analysis of sanitary napkin after exposure to UV light

No pathogens were detected on the sanitary napkin after exposure to UV light, and were considered to be safe for use.

Experiment 4: Anecdotal study The effectiveness of the sanitary napkins of the present disclosure was demonstrated by the following anecdotal study.

5 women/girls (participants A to E) between the ages of 20 to 30 years were included in the study. In order to assess the effectiveness of the sanitary napkins of the present disclosure, a specific assessment questionnaire was developed to collect information from the participants on: a. the absorption capacity of the sanitary napkins of the present disclosure as compared to the commercially available sanitary napkins; b. the comfortness (feel, fitting, odour, and the like) of the sanitary napkins of the present disclosure as compared to the commercially available sanitary napkins; c. the disposal issue of the sanitary napkins of the present disclosure as compared to the commercially available sanitary napkins; and d. any side effect (rashes or irritation) of the sanitary napkins of the present disclosure as compared to the commercially available sanitary napkins.

5 The participants A to E were asked to provide answers to the above questionnaire in terms of rating as given below:

Not as good as commercial sanitary napkin- 1 ;

Same as commercial sanitary napkin- 2;

Better than commercial sanitary napkin- 3; and 10 Best- 4.

The results are summarized in table 5.

Table 5:

It is evident from the above study that the sanitary napkin of the present disclosure had good absorption capacity (same as commercial sanitary napkins) as well as good comfortness. 15 Further, the disposal issue was solved as the sanitary napkin of the present disclosure is hot water soluble and can be disposed in the washroom itself. In addition, there were no side effects (rashes or irritation) reported by any participant.

Experiment 4: IS 5405 (1980) certification results

The sanitary napkins of the present disclosure was tested for various test parameters for IS 20 5405 certification. The test parameters and test results are summarized in Table 6 below.

Table 6: Test parameters and test results for IS 5405 certification

From the Table 5, it is evident that the sanitary napkin of the present disclosure has passed all the test parameters for the IS 5405 certification.

TECHNICAL ADVANCEMENTS AND ECONOMICAL SIGNIFICANCE

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of; a disposable absorbent product that: • is plastic free, biodegradable and compostable;

• is soluble in hot water and hence eco-friendly; and

• is bleach free and chlorine free, and hence safe;

- a process for the preparation of a disposable absorbent product that is:

• easy, environment friendly and economical.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.

Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for various physical parameters, dimensions, and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.

While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

One of the objects of the Patent Law is to provide protection to new technologies in all fields and domain of technologies. The new technologies shall or may contribute in the country economy growth by way of involvement of new efficient and quality method or product manufacturing in India.

To provide the protection of new technologies by patenting the product or process will contribute significant for innovation development in the country. Further by granting patent the patentee can contribute in manufacturing the new product or new process of manufacturing by him or by technology collaboration or through the licensing.

The applicant submits that the present disclosure will contribute in country economy, which is one of the purposes to enact the Patents Act, 1970. The product in accordance with present invention will be in great demand in country and worldwide due to novel technical features of a present invention is a technical advancement in the hygiene industry. The technology in accordance with present disclosure will provide product cheaper, saving in time of total process of manufacturing. The saving in production time will improve the productivity, and cost cutting of the product, which will directly contribute to economy of the country.

The product will contribute new concept in the hygiene industry, wherein patented process and product will be used. The present disclosure will replace the whole concept of absorbent products being used in the world from several decades. The product is developed in the national interest and will contribute to country economy. The economy significance details requirement may be called during the examination. Only after filing of this Patent application, the applicant can work publically related to present disclosure product/process/method. The applicant will disclose all the details related to the economic significance contribution after the protection of invention.

Claims

CLAIMS:

1. A disposable absorbent product comprising: a. at least one liquid permeable top layer of a first predetermined thickness; b. at least one absorbent layer of a second predetermined thickness; and c. at least one liquid non-permeable bottom layer of a third predetermined thickness; wherein said absorbent layer is disposed and bonded between the liquid permeable top layer and the liquid non-permeable bottom layer; and wherein said top layer and said bottom layer are at least partially soluble in water and said absorbent layer is at least partially dispersible in water.

2. The disposable absorbent product as claimed in claim 1, wherein said top layer and said bottom layer are at least partially soluble in water below its boiling point and said absorbent layer is at least partially dispersible in water below its boiling point.

3. The disposable absorbent product as claimed in claim 1, wherein said top layer and said bottom layer are at least partially soluble in water at a temperature in the range of 40 °C to 100 °C and said absorbent layer is at least partially dispersible in water at a temperature in the range of 40 °C to 100 °C.

4. The disposable absorbent product as claimed in claim 1, wherein said top layer and said bottom layer are completely soluble in water at 90 °C and said absorbent layer is completely dispersible in water at 90 °C.

5. The disposable absorbent product as claimed in claim 1, wherein said first predetermined thickness is in the range of 20 micron to 60 micron; said second predetermined thickness is in the range of 4 mm to 8 mm; and said third predetermined thickness is in the range of 20 micron to 60 micron.

6. The disposable absorbent product as claimed in any of the preceding claims is biodegradable.

7. The disposable absorbent product as claimed in claim 6, wherein said liquid permeable top layer is a sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

8. The disposable absorbent product as claimed in claim 6, wherein said absorbent layer is a super-absorbent polymer layer made up of a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid; wherein said material is layered and sandwiched between biodegradable tissue paper layers.

9. The disposable absorbent product as claimed in claim 8, wherein said hot water soluble fiber is selected from polyvinyl alcohol and polyvinyl pyrrolidone.

10. The disposable absorbent product as claimed in claim 8, wherein said plant based biodegradable absorbent powder is selected from the group consisting of starch, polysaccharide, sodium alginate, carboxymethyl cellulose, xanthan gel powder, gelatin powder, corn starch, karaya gum powder, guar gum powder, dry aloe vera powder, tamarind seed powder and mango seed powder.

11. The disposable absorbent product as claimed in claim 8, wherein said biodegradable pulp is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

12. The disposable absorbent product as claimed in claim 8, wherein said biodegradable air- laid is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

13. The disposable absorbent product as claimed in claim 6, wherein said non-permeable bottom layer is a non-permeable sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

14. The disposable absorbent product as claimed in any of the preceding claims is selected from baby diaper, adult diaper, sanitary napkin, panty liner, tampon and absorbent bed.

15. The disposable absorbent product as claimed in claim 1, wherein said product is packaged with a polyvinyl alcohol film having a thickness in the range of 20 micron to 60 micron.

16. A process for the preparation of a disposable absorbent product, said process comprising the steps of: a. disposing at least one absorbent layer of a first predetermined thickness between at least one liquid permeable top layer of a second predetermined thickness and at least one liquid non-permeable bottom layer of a third predetermined thickness to obtain a stack; and b. bonding said stack together by using at least one of method selected from hot water soluble stitching, water soluble gum, cold water soluble polyvinyl alcohol liquid gel, hot melting and ultrasonic welding to obtain the disposable absorbent product; wherein said top layer and said bottom layer are at least partially soluble in water and said absorbent layer is at least partially dispersible in water.

17. The process as claimed in claim 16, wherein said at least one absorbent layer is prepared by pressing or rolling a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid followed by sandwiching between biodegradable tissue paper layers.

18. A composition for making the disposable product, said composition comprising: a. at least one liquid permeable top layer having a thickness in the range of 20 micron to 60 micron, wherein said top layer is a sheet made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone; b. at least one absorbent layer having a thickness in the range of 4 mm to 8 mm, wherein said absorbent layer is a super-absorbent polymer layer made up of a material selected from hot water soluble fiber, plant based biodegradable absorbent powder, biodegradable pulp and biodegradable air-laid; and c. at least one liquid non-permeable bottom layer having a thickness in the range of 20 micron to 60 micron, wherein said bottom layer is a non-permeable film made up of a material selected from the group consisting of polyvinyl alcohol and polyvinyl pyrrolidone.

19. The composition as claimed in claim 18, wherein said hot water soluble fiber is selected from polyvinyl alcohol and polyvinyl pyrrolidone; and wherein said plant based biodegradable absorbent powder is selected from the group consisting of starch, polysaccharide, sodium alginate, carboxymethyl cellulose, xanthan gel powder, gelatin powder, corn starch, karaya gum powder, guar gum powder, dry aloe vera powder, tamarind seed powder and mango seed powder.

20. The composition as claimed in claim 18, wherein said biodegradable pulp is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

21. The composition as claimed in claim 18, wherein said biodegradable air-laid is selected from the group consisting of banana fiber pulp, bamboo fiber pulp, pine wood pulp, teak wood pulp, tamarind wood pulp, neem wood pulp and sugarcane bagasse.

22. The composition as claimed in claim 18, wherein said material selected from said hot water soluble fiber, said plant based biodegradable absorbent powder, said biodegradable pulp and said biodegradable air-laid are layered and sandwiched between biodegradable tissue paper layers.

23. The composition as claimed in claim 18, wherein said disposable product is selected from baby diaper, adult diaper, sanitary napkin, panty liner, tampon and absorbent bed.