WO2020012492A1

WO2020012492A1 - Paper mosquito coil and process of preparing the same

Info

Publication number: WO2020012492A1
Application number: PCT/IN2018/050470
Authority: WO
Inventors: Sameer GOKHALE
Original assignee: Bombay Chemicals Pvt. Ltd.
Priority date: 2018-07-13
Filing date: 2018-07-19
Publication date: 2020-01-16

Abstract

The present invention relates to a paper substrate for manufacturing a mosquito repellent coil. More particularly, the present invention relates to a paper coil comprising two more layers of the paper substrate incorporating insecticide or fragrance which can be used as mosquito repellent coil or air freshener coil respectively. The present invention also relates to a process for preparation of the said substrate and multilayer paper coil.

Description

PAPER MOSQUITO COIL AND PROCESS OF PREPARING THE SAME

FIELD OF INVENTION

BACKGROUND OF INVENTION

Conventionally the mosquito repellent coil is made from wood dust, coconut shell powder, tamarind kernel powder, charcoal powder and other chemicals and do not contain waste paper , or plant fiber; which when burnt give out toxic fumes especially carbon monoxide and carbon dioxide. Carbon powder is also toxic when burnt. The commercially available paper fiber based mosquito coils contain massive amount of synthetic perfumes which have high inhalation toxic effects. The plant fiber coils lack strength and are very wobbly and difficult to separate. Because of its wobbly nature it is difficult to place on the stand. Also the raw material consumption is large, the anti-breaking force is small, and they are easily broken.

Considering the safety hazard issue the existing mosquito coils are troublesome and inconvenient when ignited and burned.

The available paper mosquito coils are not actually made of paper but made from plant fiber, carbon powder, and felt fiber. They lack strength and are wobbly. Moreover, when burnt they give out quintessential paper burning smell which is acrid and also produce smoke as thick in volume as a conventional coil.

Further the thickness of coil is normally 2 mm and weighs around 26 gram meaning more material is used to manufacture the coil. These coils need to be dried in ovens (not good environmentally) which require fuels such as diesel to generate heat. The finish is rough, and colour is grey black, hence lacks visual appeal. The manufacturing process is also very tedious and consumes huge

SUBSTITUTE SHEETS (RULE 26) amounts of water, electricity, heat and lot of wastages take place. The punched sheets cannot be recycled and have to be discarded which is ecologically a disaster.

IPA 237/CHE/2010 discloses an aromatic paper mosquito repellent made of paper, paste of charcoal, binders like jigget, nitrates, perfumes etc. the same formulations of conventional mosquito coils. The said patent discloses about making a paste of conventional mosquito coil and just sticking it on paper in the shape of coil.

Other paper mosquito repellent available is Fast Card. Fast card is manufactured from saturating base paper of 85-180 GSM and is more like a blotting paper. The Fast Card burns for 20 seconds only with effectiveness for half hour to 45 minutes. It is extremely inconvenient from the physical usage point of view meaning that consumers do not like to keep tearing and burning time and again. Secondly one needs to put a plate under the burning fast card to prevent the ash from falling on the ground or any surface. The consumers do not like this idea. The ash is very light and tends to fly away and stick to any surfaces which is very difficult to clean later. There have been instances of houses catching fire, where burning Fast Card was carried away by wind draft due to its landing on curtains and bed sheets. This product produces huge smoke and the transfluthrin content being high, people have complained of breathing problems, nausea, vomiting, burning eyes etc. Fast card manufacturing requires ovens to dry the paper because of its high absorbent tendency. Hence usage of power is high.

Hence, conventional mosquito coils and their manufacturing process and usage are not only environmental friendly but also a big health hazard (carcinogenic & respitorial diseases) for production workers and end consumers.

Therefore, there is a need to develop a paper substrate for mosquito repellent coil that will overcome the drawbacks of the conventional mosquito repellent coils.

The present invention provides a paper substrate with specific properties for making a paper coil which can be used as mosquito repellent coil or as an air freshener. More particularly the present invention relates to a paper coil comprising two or more layers of the paper substrate comprising fiber cellulosic material incorporating insecticidal agent or suitable fragrance for its use as mosquito coil or as an air freshener. The present invention also relates to a simple, economical and industrially viable process for preparation of the said paper substrate and multilayer paper coil to be used as mosquito coil or air freshener coil.

SUMMARY OF THE INVENTION

In an aspect of the present invention, the present invention provides a paper substrate comprising fiber cellulose of poplar wood pulp, potassium nitrate and at least one insecticidal agent or fragrance agent.

In an aspect of the present invention, the present invention provides a paper coil comprising two or more layers of the said paper substrate incorporating insecticidal agent or suitable fragrance.

In another aspect, the present invention provides a process for preparation of the said paper substrate.

In yet another aspect, the present invention provides a process for preparation of a paper coil comprising two or more layers of said paper substrate.

In yet another aspect, the present invention provides a process for preparation of multilayer paper mosquito repellent coil.

In yet another aspect, the present invention provides a process for preparation of multilayer paper air freshener coil.

DESCRIPTION OF THE INVENTION

For the purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification are to be understood as being modified in all instances by the term "about". It is noted that, unless otherwise stated, all percentages given in this specification and appended claims refer to percentages by weight of the total composition. Thus, before describing the present invention in detail, it is to be understood that this invention is not limited to particularly exemplified systems or process parameters that may of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to limit the scope of the invention in any manner.

The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and in no way limits the scope and meaning of the invention or of any exemplified term. Likewise, the invention is not limited to various embodiments given in this specification.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the case of conflict, the present document, including definitions will control.

It must be noted that, as used in this specification and the appended claims, the singular forms“a,”“an” and“the” include plural referents unless the content clearly dictates otherwise.

The terms“preferred” and“preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances.

Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

As used herein, the terms“comprising”“including,”“having,”“containing,” “involving,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

As used herein the term“retention aid” means very high mass, water soluble polymers that are added to cellulosic fiber slurries before formation of paper in order to improve the efficiency with which fine particles are retained in the paper product. As used herein the term“substantially smoke free” means low volume of smoke.

In an aspect the present invention provides a paper substrate comprising fiber cellulosic material having 50 to 60 % by weight of fiber cellulose, 20-40% by weight of vessel element 10-15% by weight of ray cells, 1.5 to 4 % by weight of starch.

In an embodiment substrate further comprising at least one insecticidal agent or fragrant agent.

In another aspect the present invention provides a paper substrate comprising fiber cellulosic material having 50 to 60 % by weight of fiber cellulose, 20-40% by weight of vessel element 10-15% by weight of ray cells, 1.5 to 4 % by weight of starch;

1 to 1.5 % by weight of potassium nitrate and;

1 to 1.5 % by weight of potassium nitrate and

at least one insecticidal agent or fragrant agent.

In an embodiment the fiber cellulosic material is prepared from Poplar wood pulp. In an embodiment the length of the fibers is 3 -4mm long.

In an embodiment the paper substrate is having

- a retention aid in the range of 0.05 to 0.15 wt% or

- moisture content in the range of 5 to 9 wt% or

- rosin in the range of 0.5 to 1.5 wt% and

- ash content of less than 0.5%.

In another embodiment the paper substrate further comprises deodorized kerosene (DOK). The fragrant agent is natural essence selected from Rose oil, Lavender, Sandalwood oil, Patchouli oil, Geranium, Jasmine, Chafa or Champa, Kevra , Prajakta flower oil, Ananta flower oil and the like.

In an embodiment, the insecticidal agent is selected from the group consisting of transfluthrin, meperfluthrin, natural pyrethrum and azadirachtin (Neem extract).

In an embodiment the paper substrate is coated with suitable colour.

In another embodiment the colour is food colour selected from natural or synthetic colors. The natural colors of Strawberries (pink), Turmeric (yellow), Beet, Kathha (Red), Jamun (purple) can be used. Synthetic colors which are approved by Europe and United States FDA for example E 104 (Yellow Quinolline), E 122 Carmoisine, E 124 Ponceau 4R, E131 Patent Blue V, E 142 Green S, FD and C Erythrosine E 127 can also be used.

In an embodiment the present invention provides a multilayer paper coil the paper substrate is used for preparing used as mosquito repellant coil or air freshener coil. In an aspect the present invention a paper mosquito coil comprising

two or more paper sheets of fiber cellulosic material having 50 to 60 % of fiber and 1.5 to 4 % of starch

at least one insecticidal agent or fragrance agent.

wherein said sheets are bonded using natural gum and incorporating at least one selected from insecticidal agent, fragrance agent, potassium nitrate, essential oil and colour.

In an embodiment the present invention provides a multilayer paper coil without any filler.

In an embodiment the multilayer paper coil comprising three layers bonded to each other where the upper and bottom layer is smooth paper and middle layer is fiber paper.

In another embodiment the paper sheet for making coil is multilayer sheet. The outer layer of the paper sheet is optionally coated with a colorant. In an embodiment the multilayer coil comprising 80-95 % by weight of paper based substrate comprising fiber cellulosic material having 50 to 60 % of fiber and 1.5 to 4 % of starch.

In an embodiment the paper coil comprising mosquito repellent agent selected from Transfluthrin, Meperfluthrin, Natural Pyrethrum and Azadirachtin and is used in an amount of 0.01-0.03 % by weight.

In an embodiment the papers coil comprising Transfluthrin.

In an embodiment the papers coil comprising Transfluthrin in an amount of 0.03% by weight.

In an embodiment the papers coil comprising 1 to 1.5 % by weight of potassium nitrate and 1-2% by weight of essential oil.

In an embodiment the multilayer paper coil is substantially smoke free.

The paper coil in accordance with the present invention is made from fiber cellulose substrate. There are no conventional mosquito coil materials involved in the process. Because the paper coil eliminates all the conventional mosquito coil ingredients, e.g. carbon powder, solvent such as Isopropyl Myristate and Denatonium benzoate which is bitter agent. It is thus far safer to use and is substantially smoke free.

In an aspect the present invention provides a process for preparing the paper substrate comprising:

a) mashing and segregating poplar wood to obtain fibers;

b) washing the fibers with alkaline solution;

c) pressing said washed fibers and drying to form paper sheet;

d) treating the paper sheets with solution comprising potassium nitrate and/or deodorized kerosene to obtain the paper substrate.

The alkaline solution comprises hydrogen peroxide and at least one of magnesium salt, sodium silicate. Optionally sodium dithionite is added to brighten up the pulp. improve the whiteness of paper. In an embodiment the process for preparation of the paper substrate is carried out at room temperature.

The paper substrate as produced is cut into a desired shape, dried at room temperature and packed.

Thus the process of preparing the paper substrate and multilayer paper coil involves less labour cost, no generation of heat. As the process does not use of any carcinogenic materials or solvents for the preparation of substrate or multilayer paper coil; therefore it does not cause any respitorial diseases to the workers or end users.

Further, the process of manufacturing the multilayer paper coil for mosquito repellant of the present invention is simple, cost effective, environment friendly over the conventional mosquito coils as there is no depletion of natural materials. Moreover, the multilayer paper coils are light, easy to carry and can be used without breakage and are smoke-free.

In an aspect, the present invention provides a process for preparing the multilayer paper coil comprising:

a. preparing the sheet of the paper substrate,

b. cutting said sheet to the desired size to obtain cut sheets;

c. bonding at least two or more cut sheets to form a multilayer sheet;

d. optionally coating the exterior sides of the multilayer sheet with colorant; e. drying the multilayer sheet and moulding to obtain multilayer paper coil.

In an embodiment the paper substrate is treated either with insecticidal agent to prepare mosquito repellant paper coil or with fragrant agent to prepare air freshener.

In another embodiment the paper coil is having thickness in the range of about 0.1-0.5 mm. Alternatively, in another embodiment, the paper based substrate is made from waste paper materials recovered from the waste packing materials after use in the industries or wood based material for example Poplar tree wood pulp which is soft wood, cotton like feel or waste material which made from Poplar tree wood pulp for example containers of food and beverages, packages of medicines etc., Poplar wood is also commonly used for the manufacture of pulp and paper products such as tissues, napkins, towels, fine paper, paper board for packaging, insulation boards, ceiling tiles, hardboards and the like.

Typically the waste wood material is collected from Industries using Poplar wood and from factories using pulp and paper products; the material is mashed and segregated into fibers; the fibers are washed with alkaline hydrogen peroxide solution to remove impurities; the fibers are then pressed mixed with gums to form long sheets of desired thickness e.g.O.lmm and dried to obtain paper substrate.

Paper sheets/substrate made from poplar wood are white to off-white in colour having high fiber contents, strength and stiffness. The paper substrate is bonded on both sides with thinner paper substrates using gum. The bonded sheet thus formed has a thickness of about 0.5mm.

The sheets are dried in the sun and then cut by stainless steel moulds or can be cut by lazor machines in the shape of spiral coil.

In another embodiment present invention provides a paper mosquito coil comprising

at least one insecticidal agent or fragrance agent

wherein said sheets are bonded using natural gum and incorporating at least one selected from insecticidal agent, fragrance agent, potassium nitrate, essential oil and colour. In another embodiment the multilayer paper coil comprising at least three paper sheets layered over each other to from a multilayer structure. The outer layer(s) of the paper sheet is optionally coated with a colorant.

In another embodiment the multilayer sheet comprising 80-95 % by weight of paper based substrate comprising fiber cellulosic material having 50 to 60 % of fiber and 1.5 to 4 % of starch.

In another embodiment the paper coil comprising 1 to 1.5 % by weight of potassium nitrate, 1-2% by weight of essential oil and 0.01-0.03 % by weight of at least one mosquito repellent agent.

In another embodiment the present invention provides a process for preparing the paper mosquito coil comprising:

a) mashing poplar wood pulp and segregating the fiber cellulosic material b) washing fiber cellulosic material with alkaline solution and drying to obtain paper substrate sheet

c) cutting said sheet to the desired size to obtain cut sheets

d) bonding at least two or more cut sheets using natural gum

e) optionally coating the bonded sheet with colour;

f) dipping the layered paper sheet in a solution containing at least one selected from insecticidal agent, fragrance agent, potassium nitrate, essential oil and colour.

g) drying paper sheet and moulding to obtain paper coil.

In another embodiment the paper substrate is treated either with insecticidal agent to prepare mosquito repellant paper coil or with fragrant agent to prepare air freshner coil.

In another embodiment the paper based substrate for mosquito repellent coil transformed into a desired shape. Examples of the shape include a circular spiral shape, a polygonal spiral shape, a rod shape, a cylindrical shape, a tubular shape, a flat plate shape, a lump shape, and the like. For molding, an extrusion molding machine or the like may be used. After molding, in order to remove moisture, it is sufficiently dried by conventional methods to obtain the mosquito coil of the present disclosure.

In an embodiment the paper substrate is ECF (Elemental Chlorine Free) and TCF (Total Chlorine Free) pulp. As Chlorine is toxic when burnt, the chlorine free paper substrate is non-toxic when burnt.

In another embodiment the paper substrate is recyclable.

In accordance with the embodiments of the present invention, the multilayer paper coil is about 0.5 mm thick, and weighs just 4 grams in dry form. Hence, less material and more number of coils can be produced with the same tonnage of material as plant fiber materials.

In accordance with the embodiments of the present invention, the dipped and dried paper coil weighs 6.4 to 7 grams.

In accordance with the embodiments of the present invention about 0.5mm coils require less packaging materials which is eco-friendly and since thickness of the paper coil is about 0.5mm thereby it produces less amount of smoke.

In accordance with further embodiments of the present invention, the paper coil having 0.5mm thickness burns for 5 hours under no draft conditions, with another 4 hours of residual effect.

The multilayer paper coil is easy to separate and place on the cross sectional stand due to better strength and better stiffness.

In an embodiment, the multilayer paper coils can be packed in recyclable paper bags. Bags will be made from waste paper and do not require plastic.

In another embodiment, the multilayer paper coils can be packed in aluminum foil lined zip bags.

Paper coils prepared according to the present invention are economical and cheaper than the conventional coils and plant fiber coils and other mosquito repellents or air freshener products commercially available in the markets. The multilayer paper coil of the present invention does not use carbon powder, plant fiber in its production. The multilayer paper coil is strong, durable, and stiff and can last for years together due to its high absorbing and retaining capacity.

The advantages of present invention:

1. The paper substrate or sheet is non-toxic, non-hazardous, recyclable, food grade materials.

2. The paper coil has pure 100% paper and no filler material is added or used.

3. Any wastage generated in the factory and any returns from the markets, the entire product is recyclable.

4. The multilayer paper coil minimizes the quantity of the ingredients used.

5. The absorption rate of the paper substrate is high, especially when adding natural essential oils.

6. Requires very less labour and the entire process can be automized.

7. The process is very simple and it does not require artificially generated heat, thus no wastages.

8. The multilayer paper coil 0.5mm thick and weighs just 4 grams in dry form. Considering the light weight less material and more number of coils can be produced with the same tonnage of material as plant fiber materials and requires less packaging materials which is eco-friendly.

9. As the multilayer paper coil is only 0.5mm thick it produces negligible amount of smoke and burns for 5 hours under no draft conditions, with another 4 hours of residual effect.

10. The multilayer paper coils are easy to separate and place on the stand due to better strength and better stiffness.

11. The multilayer paper coil is strong, durable, stiff and can last for years together due to its high absorbing and retaining capacity.

The following examples are provided to better illustrate the claimed invention and are not to be interpreted in any way as limiting the scope of the invention. One skilled in the art may develop equivalent materials, and methods without the exercise of inventive capacity and without departing from the scope of the invention. It is the intention of the inventors that such variations are included within the scope of the invention.

EXAMPLES:

Example 1: Preparation of multilayer paper based mosquito repellent coil

A poplar wood material was crushed to make powder and passed through mesh sieve of size 150-200 microns and segregated into fiber. The paper pulp is washed with solution of hydrogen peroxide and at least one of magnesium salt, sodium silicate and sodium dithionite. The bleached fiber material is then pressed with gum and rolled to obtain thin fiber sheets. Three sheets thus formed are bonded to each other on the inner side with natural gum obtained from rice or tapioca paste to obtain a board. The board is then dipped in a solution comprising 1.44 wt% of potassium nitrate and at least one insecticide selected from Transfluthrin (0.03%), Meperfluthrin (0.01%), Natural Pyrethrum (0.2% ) and Azadirachtin (Neem Based, 4-5%) for 5 minutes. Essential oils and colours are added not more than 4- 5% and as per strength of each material. Certain essential oils are strong, hence less amount is requires, the same applies to colours. The board was then dried using conventional drying method or by exposing to sunlight and moulded into desired size or cut in the shape of spiral coil to obtain a multilayer mosquito repellent coil.

The coil produces substantially less smoke. Therefore it is tolerant to even sensitive people suffering from respitorial diseases, asthma or allergies. The manufacturing of coil product is industrially viable and very economical. The coil of the present invention is very light, weighing maximum if 6.4 g. After burning, the coil leave very little of ash. The coil thus produced is absolutely in flat form, very smooth finish, high in strength and do no break while separating the multiple coils.

Claims

WE CLAIM:

1. A paper substrate comprising a fiber cellulosic material having 50 to 60 % by weight fiber content, 20-40% by weight vessel element, 10-15% by weight ray cells, 1.5 to 4 % by weight starch and 1 to 1.5 % by weight of potassium nitrate.

2. The substrate as claimed in claim 1, wherein the fiber cellulosic material is obtained from poplar wood pulp.

3. The substrate as claimed in claim 1, wherein the length of the fibers is 3 -4mm long.

4. The substrate as claimed in claim 1 wherein said substrate further comprising at least one insecticidal agent or fragrant agent.

5. The substrate as claimed in claim 1 wherein said substrate further comprises deodorized kerosene.

6. The paper substrate as claimed in claim 1 having

- a retention aid in the range of 0.05 to 0.15 wt % or

- moisture content in the range of 5 to 9 wt % or

- rosin in the range of 0.5 to 1.5 wt % and

- ash content of less than 0.5%.

7. The paper substrate as claimed in claim 1, wherein said insecticide is selected from the group consisting of transfluthrin, meperfluthrin, natural pyrethrum and azadirachtin .

8. The paper substrate as claimed in claim 1, wherein said fragrant agent is natural essence selected from Rose oil, Lavender, Sandalwood oil, Patchouli oil, Geranium, Jasmine, Chafa or Champa, Kevra , Prajakta flower oil, Ananta flower oil and the like.

9. The paper substrate as claimed in claim 1, wherein the colorant is natural or synthetic color selected from Strawberries (pink), Turmeric (yellow), Beet, Kathha (Red), Jamun (purple) E 104 (Yellow Quinolline), E 122 Carmoisine, E 124 Ponceau 4R, E131 Patent Blue V, E 142 Green S, FD and C Erythrosine E 127.

10. A process for preparing the paper substrate as claimed in claim 1 comprising: a) mashing and segregating poplar wood to obtain fibers;

b) washing the fibers with alkaline solution;

c) pressing said washed fibers and drying to form paper sheet;

11. The process as claimed in claim 8, wherein said process is carried out at room temperature.

12. The process as claimed in claim 8, wherein the alkaline solution comprises hydrogen peroxide and at least one of magnesium salt, sodium silicate and sodium dithionite.

13. A paper mosquito coil comprising

at least one insecticidal agent or fragrance agent

wherein said sheets are bonded using natural gum and incorporating at least one ingredient selected from insecticidal agent, fragrance agent, potassium nitrate, essential oil and colour.

14. The paper coil as claimed in claim 13 is multilayer coil comprising at least three paper sheets layered over each other to from a multilayer structure.

15. The paper coil as claimed in claim 13 wherein said multilayer sheet comprising 80-95 % by weight of paper based substrate comprising fiber cellulosic material having 50 to 60 % of fiber and 1.5 to 4 % of starch.

16. The paper coil as claimed in claim 14 wherein outer layer of the paper sheet is optionally coated with a colorant.

17. The paper coil as claimed in claim 13 wherein said coil comprising 1 to 1.5 % by weight of potassium nitrate and 1-2% by weight of essential oil.

18. The paper coil as claimed in claim 13 wherein said insecticidal agent is mosquito repellent agent.

19. The paper coil as claimed in claim 18 wherein said mosquito repellent agent is selected from Transfluthrin, Meperfluthrin, Natural Pyrethrum and Azadirachtin and is used in an amount of 0.01-0.03 % by weight.

20. The paper coil as claimed in claim 13 is substantially smoke free.

21. The paper coil as claimed in claim 13 is having thickness in the range of 0.1- 0.5 mm.

22. A process for preparing the paper mosquito coil comprising:

c) cutting said sheet to the desired size to obtain cut sheets

d) bonding at least two or more cut sheets using natural gum

e) optionally coating the bonded sheet with colour;

g) drying paper sheet and moulding to obtain paper coil.

23. The process for preparing the multilayer paper coil as claimed in claim 11, wherein the paper substrate is treated either with insecticidal agent to prepare mosquito repellant paper coil or with fragrant agent to prepare air freshener coil.