Title of Invention	"AN IMPROVED PROCESS FOR THE PREPARATION OF DEGUMMED RAMIE (BOEHMERIA NIVEA GAUD) FIBRES"
Abstract	The present invention reports an improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres which comprises treating decorticated fibres free from adsorbed impurities with a bath comprising of hydrolysing agent and hydrolysis controlling agents and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres.

Title of Invention

"AN IMPROVED PROCESS FOR THE PREPARATION OF DEGUMMED RAMIE (BOEHMERIA NIVEA GAUD) FIBRES"

Abstract

The present invention reports an improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres which comprises treating decorticated fibres free from adsorbed impurities with a bath comprising of hydrolysing agent and hydrolysis controlling agents and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres.

Full Text	This invention relates to an improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres. Ramie plant produces an exceptionally strong fibre, which is stronger than any known fibre. It is seven (7) to eight (8) times stronger than cotton fibre. This Ramie fibre can be used for variety of purposes. It (fibre) can be used for making rope, twine, fish net, dress goods, yarn and also as a raw material for cellulose derivatives, pulpfibre for blending with wool and synthetic yarn for making varieties of items and cloth. The term degumming describes herein indicates the process whereby fibre present in the ramie plant mixed with a variety of other ingredients are let free by disolving the binding materials. Ramie plant contains about 20-30% gum which must therefore, be removed or to bring, a certain level by conventional degumming technique in order to utilize its fibre. Ramie fibre is usually extracted by retting-an ancient practice of degumming. But it is an unsuitable cumbersome and labour intensive affair and therefore, less economical. The product obtained is non uniform as well as imperfect too. This discourages cultivators and producers. In this system, Ramie leaves are removed from the stems after harvesting and prior to retting. These are then arranged in small bundles. Sometimes, woody portion is broken down before this arrangement. After this operation bundles of Ramie are exposed for wetting for 3 to 4 weeks in open field. When bust portion soften, it is then removed, cleaned washed to free the fibres and then allowed to dry. In an another practice, the bust portion is manually removed through peeling by braking the woody portion in the middle just after harvesting and cleaning of leaves. These are then bundled and kept in saline or in muddy water for fungal attack. After 2 to 4 weeks, depending on temperature, humidity and light bust portion soften due to releasing of adhearing substances. It is then washed throughly, combed, cleaned and allowed to dry. Chemical degumming on the other hand is free from all these defects and therefore prefered than retting process. In chemical process, gums are removed by hydrolysis and then desolving in water to free the fibres. By the process more uniform and strong fibres can be obtained. Of course, in chemical degumming process, usually a pretreatment is given in the decorticated fibre before degumming. Literatures indicate the use of enzymes such as aspergillus versicolor-a cell wall degrading enzyme, pactinase produce by bacil- lus sp No 5, pectinolytic Clostridium corallium etc. for this work. Generally surface active chemicals are utilised for this purpose and some times both are used making a biological and chemical method intermixed for softening and degumming.One such information is, the use of bacillus subtiles mutant T66 ( Lin Zhen Chi, Luo Caian et al peop. Rep. of China, Fangzhi Xuebao, 1991, 12(10), 458-60, 467(Ch) followed by Na-triphosphate treatment as a method of degumming. For softening priorto degumming in China, patassium sulfate or aluminium sulfate is used where decorticated fibres are kept for 12 hours before degumming with sodium hydroxide (NaoH) at boiling temperature for 2 to 6 hours. It is furthere treated thereafter with sodium perborate. In USA sodium hydroxide (NaoH) alone or in combination with sodium sulfate to enhance hydrolysis under temperature is the general pratice of degumming ramie by chemical method. Some of the patents literature cited and referred such chemicals and techniques as given under: UK Patent appl. No.GB 2085 500 (Sen,Swapan Kumar)- ^>r'J 28 April, 1982. Wherein described degumming of leaves, fibres carried out by giving initial treatment with non-ionic, detergent (1- 10%), 0.2-2% H SO at 1-5 atm. at 80- 2 4 o 100 C and thereafter treated with a bleaching chemical using 6% available chlorine. After which the material further treated with antichlor compound and then with NaOH, KOH, NA SO (1-17.5%) and softner at boiling 2 4 temperature. US Patent Appl. No. 554256-Jaskowshi Michaele (Helmie Inc) - 22nd November, 1983. Here degumming is carried out by appliction of biological and chemical method stepwise. Here decorticated fibre is washed with surface active agent and water initially. Then it is treated with pactinasewan enzyme, for 15 minutes at acidic PH(PH 2.5-4). It is then washed, treated further with chlorine. Indian Patent Appl. No. 72/2,05004- (Indian Council of Agricultural Research) - December 1972. Where degumming is done under pressure and high temperature using 1-2% NaOH at 115-125 C at 10-19 PSI for 2 hrs. Subsequent to this operation, the material is washed with cold water and there after with acetic acid Solution (1%) under bath ratio 1:5 (fibre:bath) and then further treated with surfactant. The present invention, differs from the above cited patents is that no pretreament in order to soften the material with softener then sulphuric acid treatment, bleaching with chlorine prior to cooking at boiling temperature with NaOH, KOH, Na SO with as high concentration as 1-17.5% is used in degumming as given in UK Patent application No. GB 2085500. Neither the present invention contains biological and chemical intermixed degumming method applied as mentioned in US Patent Appl. No. 554256 nor high temperaturte and high pressure cooking system using NaOH and acid and thereafter surfactant treatment for degumming is used as in the Indian patent appl. no. 72/205004. The main object of the present invention is to provide a simple process without high temperature and application of pressure and with cheaper chemicals to obviate the drawback as detailed above. Another objective is to avoid biological and chemical method intermixed for degumming which is labourious and require high skill and supervision. Still anoher object of the present invention is to reduce steps as mentioned in cited patents such as softening, partial degumming using of bleaching chemicals prior to full degumming under pressure and temperature and the use of surfactant washing as different steps in degumming. Accordingly , the present invention provides an improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres which comprises treating decorticated fibres free from adsorbed impurities with a bath comprising of 0.25 to 20 gm of hydrolysing agent selected from carbonate of sodium, potassium or ammonium and hydrolysis controlling agents such as 0.1 to 12 gm of ammonium or potassium persulfate 0.03 to 15 gm of sodium or hydrogen peroxide, 0.1 to 6 gm of polyoxyemylene sorbitan mono oleate 0.25 to 20 gm of sodium sulfite or mixture there of per hundred gm of fibres and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres. The fibres are then washed with water or if desired with hydrochloric acid water mixed (0.5 to 4%) or with any surface cleaning compound to remove the chemicals adhering to degummed fibre. The fibres can be bleached if desired with bleaching compound more preferably with calcium hypochlorite or sodium hypochlorite in a single step or with more than one step to get the desired whiteness using 3 to 10% avaitable chlorine per 100 gms of degummed fibre preferably at a temperature 30 to 75 C for 1 to 8 hrs. There after the material be washed free of bleached chemical and then dried. Drying of the degummed fibre can be done by passing hot air in closed chamber or in an oven or by any suitable heating device. The most preferable range is 40 to 85 C. If desired it can be sun dried. The final product yield is 68 to 92% and degumming rate is 55 to 96%. The percentage of degumming can be determined by Xray method or by any known chemical method using acidic softwater. The marked novelty of the present invention is that the process steps are very simple to follow. No costly chemicals or equipments are needed for degumming. If desired the bleaching system can be included in the degumming stage avoiding as distinct separate step after complete degumming of the material. The following examples are given by way of illustration of the present invention and should not be constured to limit the scope of the present invention. Example - 1 100 gm of decorticated ramie fibre of 6" length is taken in a 2 litre capacity flat bottom flask made of glass or stainless steel. The flask is kept on a heating mantle with necessary device to adjust the temperature. To the flask 500 ml. iron free water is added. Then another 300 ml. water containing 11 gm sodium carbonate 3 gm. Sodium sulfite, 1 gm. potassium persul-fate, 0.3 gm. polyoxyethylene sorbitan mono oleate added therein are mixed properly. Then the entire solution is added in the vessel making the bath ratio o 1:8. It is then heated to 50-75 C for 3 hrs. with occassional strring. After the completion of the said period the temperature is brought to room temperature. o Thereafter it is thoroughly washed and dried at 50-80 C for 6 hrs. The dried material has an yield of 87% with a degumming rate of 86%. Example - 2 In another experiment 100 gm. of decorticated fibre of stated length is kept in a flat bottom stail- ness steel vessel containing 1000 ml. iron free water, 10 gm. potassium carbonate, 1.5 gm. potassium persul- fate, 10 gm. sodium peroxide. 0.4 gm. polyoxy ethylene sorbitan mono oleate in it. It is then heated in a o o water bath at 90-100 C for 2 and 1/2 hrs. at 100-120 C with occasional stirring, keeping the ratio 1:10 as constant. After the completion of the said period the material is removed from the container and washed with tap water and then neutralised with 0.5% acid water and o twisted to remove water. It is then dried at 60-80 C for 5 hrs. The yield of the product is 78% with a degumming rate of 94%. The whiteness of the fibre is 65%. Example - 3 150 gm. of decorticated 6" size ramie fibre is kept in a chemical bath containing 15 gm. ammonium carbonate, 1.5 gm polyoxyethylene sorbitan mono oleate, 15 gm. hydrogen peroxide (HO) taken in a 4 litre 2 2 capacity flat bottom container with 800 ml. of iron o free water at room temperature (20-30 C) for 16 hrs. After the said period the material is removed and with a mild wasing transferred to an another similar container with 500 ml. iron free water, 7.5 gm sodium o sulfite, 10 gm sodium carbonate and heated to 50-60 C for 1 hr and then 95-108 C for another 1 hour more. After the said period the material is washed repeatedly with tap water to remove the chemicals. Then it is sun o dried for 16 - 20 hrs. or kept in an oven at 70-90 C for 5 hrs. after removing water as much as possible by pressing and squezing which remove 34-36% water present after degummed and washed fibre. The yield of the dried fibre was 78% and with 93% gummed removed. Example 4 500 gm. of decorticated ramie fibre (6") is taken in a suitable stainless steel container, 25 gm of sodium carbonate, 20 gm sodium sulfate, 3 gm potassium persulfate are mixed thoroughly with 3750 ml of iron free water. Thereafter the entire solution is added in the container containing 300 gm. decorticated fibre and kept for 24 hrs. After the said period the material is washed with water to free the chemicals. Thereafter it o is bleached with 6% hypochlorite for 3 hrs. at 40-50 C 9pH 10.5). It is then washed with water and finally with 0.5% acid solution. The yield of dried bleached fibre is 85% and percentage of degumming was found to be 89%. Example - 5 100 gm of hand peeled ramie fibre (10"-16") is taken in stainless steel container and placed in an orderly manner. In an separate glass vessel of 2 litre capacity, 11 gm sodium carbonate, 5 gm ammonium persul- fate, 6 gm hydrogen peroxide ;and 2 gm polyoxyethylene sorbitan mono oleate are desolved with 500 ml of iron free water and mixed throughly. Then another 1000 ml water is added therein making the total added water to 1,5000 ml. Thereafter the whole amount containing the chemicals is poured in the container containing the fibre. The entire system is allowed to stand for 90 o hrs. at room temperature (22-27 C). Thereafter the material is removed and washed in running tap water to remove the chemicals. The degummed fibres then dried in an oven at 50-80 for 4 hrs. The yield was found to be 79% and percentage of degumming is 91%. The main advantages of the present invention are: 1. The process is simple to follow and no costly chemi cals are used in degumming. 2. The process can be utilised to achieve any desired degumming i.e. the rate of degumming of constituent binding material can be kept at any desired level without any change of constituent chemicals used for the degumming. 3. No intermediate steps such as softening, part degumming, bleaching before actual degumming of fibre is necessary in the process. 4. The degumming can be done without pressure application or by eliminating high temperature system. We Claim : 1. An improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres which characteriset they decorticated fibres free from adsorbed impurities with in a bath comprising of 0.25 to 20 gm of hydrolysing agent selected from carbonate of sodium, potassium or ammonium and hydrolysis controlling agents such as 0.1 to 12 gm of ammonium or potassium persulfate 0.03 to 15 gm of sodium or hydrogen peroxide, 0.1 to 6 gm of polyoxyethylene sorbitan mono oleate 0.25 to 20 gm of sodium sulfite or mixture there of per hundred gm of fibres and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres. 2. An improved process as claimed in claim 1, where in the treatment is effected at 40 to 100° C for 1 to 8 hrs., at room temperature for 20 to 300 hrs, at 50 to 75° C for 2 to 6 hrs or at 110 to 140°C for 1 to 5 hrs. 3. An improved process as claimed in claim 1 and 2, where in the washing may be carried out using water or acidic water (0.5 to 4% acid) or any surface cleaning compound . 4. An improved process as claimed in claim 1 to 3 , where in the bleaching is effected by calcium or sodium hypochlorite having 3 to 10% available chlorine per 100 gm of fibres. 5. An improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres substantially as herein described with reference to examples.

Full Text

This invention relates to an improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres.
Ramie plant produces an exceptionally strong fibre, which is stronger than any known fibre. It is seven (7) to eight (8) times stronger than cotton fibre. This Ramie fibre can be used for variety of purposes. It (fibre) can be used for making rope, twine, fish net, dress goods, yarn and also as a raw material for cellulose derivatives, pulpfibre for blending with wool and synthetic yarn for making varieties of items and cloth.
The term degumming describes herein indicates the process whereby fibre present in the ramie plant mixed with a variety of other ingredients are let free by disolving the binding materials. Ramie plant contains about 20-30% gum which must therefore, be removed or to bring, a certain level by conventional degumming technique in order to utilize its fibre.
Ramie fibre is usually extracted by retting-an ancient practice of degumming. But it is an unsuitable cumbersome and labour intensive affair and therefore, less economical. The product obtained is non uniform as well as imperfect too. This discourages cultivators and producers.
In this system, Ramie leaves are removed from the stems after harvesting and prior to retting. These are then arranged in small bundles. Sometimes, woody portion is broken down before this arrangement. After this operation bundles of Ramie are exposed for wetting for 3 to 4 weeks in open field. When bust portion soften, it is then removed, cleaned washed to free the fibres and then allowed to dry. In an another practice, the bust portion is manually removed through peeling by braking the woody portion in the middle just after harvesting and cleaning of leaves. These are then bundled and kept in saline or in muddy water for fungal attack. After 2 to 4 weeks, depending on temperature, humidity and light bust portion soften due to releasing of adhearing substances. It is then washed throughly, combed, cleaned and allowed to dry.
Chemical degumming on the other hand is free from all these defects and therefore prefered than retting process. In chemical process, gums are removed by hydrolysis and then desolving in water to free the fibres. By the process more uniform and strong fibres can be obtained. Of course, in chemical degumming process, usually a pretreatment is given in the decorticated fibre before degumming. Literatures indicate the use of enzymes such as aspergillus versicolor-a cell wall degrading enzyme, pactinase produce by bacil-
lus sp No 5, pectinolytic Clostridium corallium etc. for this work. Generally surface active chemicals are utilised for this purpose and some times both are used making a biological and chemical method intermixed for softening and degumming.One such information is, the use of bacillus subtiles mutant T66 ( Lin Zhen Chi, Luo Caian et al peop. Rep. of China, Fangzhi Xuebao, 1991, 12(10), 458-60, 467(Ch) followed by Na-triphosphate treatment as a method of degumming. For softening priorto degumming in China, patassium sulfate or aluminium sulfate is used where decorticated fibres are kept for 12 hours before degumming with sodium hydroxide (NaoH) at boiling temperature for 2 to 6 hours. It is furthere treated thereafter with sodium perborate. In USA sodium hydroxide (NaoH) alone or in combination with sodium sulfate to enhance hydrolysis under temperature is the general pratice of degumming ramie by chemical method. Some of the patents literature cited and referred such chemicals and techniques as given under:
UK Patent appl. No.GB 2085 500 (Sen,Swapan Kumar)- ^>r'J 28 April, 1982.
Wherein described degumming of leaves, fibres
carried out by giving initial treatment with non-ionic,
detergent (1- 10%), 0.2-2% H SO at 1-5 atm. at 80-
2 4 o 100 C and thereafter treated with a bleaching chemical
using 6% available chlorine. After which the material
further treated with antichlor compound and then with
NaOH, KOH, NA SO (1-17.5%) and softner at boiling 2 4
temperature.
US Patent Appl. No. 554256-Jaskowshi Michaele (Helmie Inc) - 22nd November, 1983.
Here degumming is carried out by appliction of biological and chemical method stepwise. Here decorticated fibre is washed with surface active agent and water initially. Then it is treated with pactinasewan enzyme, for 15 minutes at acidic PH(PH 2.5-4). It is then washed, treated further with chlorine.
Indian Patent Appl. No. 72/2,05004- (Indian Council of Agricultural Research) - December 1972.
Where degumming is done under pressure and high
temperature using 1-2% NaOH at 115-125 C at 10-19 PSI
for 2 hrs. Subsequent to this operation, the material is washed with cold water and there after with acetic acid Solution (1%) under bath ratio 1:5 (fibre:bath) and then further treated with surfactant.
The present invention, differs from the above cited patents is that no pretreament in order to soften the material with softener then sulphuric acid treatment, bleaching with chlorine prior to cooking at
boiling temperature with NaOH, KOH, Na SO with as high
concentration as 1-17.5% is used in degumming as given
in UK Patent application No. GB 2085500. Neither the present invention contains biological and chemical intermixed degumming method applied as mentioned in US Patent Appl. No. 554256 nor high temperaturte and high pressure cooking system using NaOH and acid and thereafter surfactant treatment for degumming is used as in the Indian patent appl. no. 72/205004.
The main object of the present invention is to provide a simple process without high temperature and application of pressure and with cheaper chemicals to obviate the drawback as detailed above.
Another objective is to avoid biological and chemical method intermixed for degumming which is labourious and require high skill and supervision.
Still anoher object of the present invention is to reduce steps as mentioned in cited patents such as softening, partial degumming using of bleaching chemicals prior to full degumming under pressure and temperature and the use of surfactant washing as different steps in degumming.
Accordingly , the present invention provides an improved process for the preparation
of degummed Ramie (Boehmeria nivea GAUD) fibres which comprises treating
decorticated fibres free from adsorbed impurities with a bath comprising of 0.25 to 20
gm of hydrolysing agent selected from carbonate of sodium, potassium or
ammonium and
hydrolysis controlling agents such as 0.1 to 12 gm of ammonium or potassium persulfate 0.03 to 15 gm of sodium or hydrogen peroxide, 0.1 to 6 gm of polyoxyemylene sorbitan mono oleate 0.25 to 20 gm of sodium sulfite or mixture there of per hundred gm of fibres and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres.
The fibres are then washed with water or if desired with hydrochloric acid water mixed (0.5 to 4%) or with any surface cleaning compound to remove the chemicals adhering to degummed fibre. The fibres can be bleached if desired with bleaching compound more preferably with calcium hypochlorite or sodium hypochlorite in a single step or with more than one step to get the desired whiteness using 3 to 10% avaitable chlorine per
100 gms of degummed fibre preferably at a temperature
30 to 75 C for 1 to 8 hrs. There after the material be
washed free of bleached chemical and then dried. Drying
of the degummed fibre can be done by passing hot air in
closed chamber or in an oven or by any suitable heating
device. The most preferable range is 40 to 85 C. If
desired it can be sun dried.
The final product yield is 68 to 92% and degumming rate is 55 to 96%. The percentage of degumming can be determined by Xray method or by any known chemical method using acidic softwater. The marked novelty of the present invention is that the process steps are very simple to follow. No costly chemicals or equipments are needed for degumming. If desired the bleaching system can be included in the degumming stage avoiding as distinct separate step after complete degumming of the material.
The following examples are given by way of illustration of the present invention and should not be constured to limit the scope of the present invention.
Example - 1 100 gm of decorticated ramie fibre of 6" length is taken in a 2 litre capacity flat bottom flask made of glass or stainless steel. The flask is kept on a heating mantle with necessary device to adjust the temperature. To the flask 500 ml. iron free water is added. Then another 300 ml. water containing 11 gm sodium carbonate 3 gm. Sodium sulfite, 1 gm. potassium persul-fate, 0.3 gm. polyoxyethylene sorbitan mono oleate added therein are mixed properly. Then the entire
solution is added in the vessel making the bath ratio
o 1:8. It is then heated to 50-75 C for 3 hrs. with
occassional strring. After the completion of the said
period the temperature is brought to room temperature.
o Thereafter it is thoroughly washed and dried at 50-80 C
for 6 hrs. The dried material has an yield of 87% with
a degumming rate of 86%.
Example - 2
In another experiment 100 gm. of decorticated
fibre of stated length is kept in a flat bottom stail-
ness steel vessel containing 1000 ml. iron free water,
10 gm. potassium carbonate, 1.5 gm. potassium persul-
fate, 10 gm. sodium peroxide. 0.4 gm. polyoxy ethylene
sorbitan mono oleate in it. It is then heated in a
o o
water bath at 90-100 C for 2 and 1/2 hrs. at 100-120 C
with occasional stirring, keeping the ratio 1:10 as
constant. After the completion of the said period the
material is removed from the container and washed with
tap water and then neutralised with 0.5% acid water and
o twisted to remove water. It is then dried at 60-80 C
for 5 hrs. The yield of the product is 78% with a degumming rate of 94%. The whiteness of the fibre is 65%.
Example - 3 150 gm. of decorticated 6" size ramie fibre is kept in a chemical bath containing 15 gm. ammonium carbonate, 1.5 gm polyoxyethylene sorbitan mono oleate,
15 gm. hydrogen peroxide (HO) taken in a 4 litre
2 2
capacity flat bottom container with 800 ml. of iron
o free water at room temperature (20-30 C) for 16 hrs.
After the said period the material is removed and with a mild wasing transferred to an another similar container with 500 ml. iron free water, 7.5 gm sodium
o sulfite, 10 gm sodium carbonate and heated to 50-60 C
for 1 hr and then 95-108 C for another 1 hour more.
After the said period the material is washed repeatedly
with tap water to remove the chemicals. Then it is sun
o dried for 16 - 20 hrs. or kept in an oven at 70-90 C
for 5 hrs. after removing water as much as possible by
pressing and squezing which remove 34-36% water present
after degummed and washed fibre. The yield of the dried
fibre was 78% and with 93% gummed removed.
Example 4
500 gm. of decorticated ramie fibre (6") is taken
in a suitable stainless steel container, 25 gm of
sodium carbonate, 20 gm sodium sulfate, 3 gm potassium
persulfate are mixed thoroughly with 3750 ml of iron
free water. Thereafter the entire solution is added in
the container containing 300 gm. decorticated fibre and
kept for 24 hrs. After the said period the material is
washed with water to free the chemicals. Thereafter it
o is bleached with 6% hypochlorite for 3 hrs. at 40-50 C
9pH 10.5). It is then washed with water and finally
with 0.5% acid solution. The yield of dried bleached
fibre is 85% and percentage of degumming was found to
be 89%.
Example - 5
100 gm of hand peeled ramie fibre (10"-16") is
taken in stainless steel container and placed in an
orderly manner. In an separate glass vessel of 2 litre
capacity, 11 gm sodium carbonate, 5 gm ammonium persul-
fate, 6 gm hydrogen peroxide ;and 2 gm polyoxyethylene
sorbitan mono oleate are desolved with 500 ml of iron
free water and mixed throughly. Then another 1000 ml
water is added therein making the total added water to
1,5000 ml. Thereafter the whole amount containing the
chemicals is poured in the container containing the
fibre. The entire system is allowed to stand for 90
o hrs. at room temperature (22-27 C). Thereafter the
material is removed and washed in running tap water to
remove the chemicals. The degummed fibres then dried
in an oven at 50-80 for 4 hrs. The yield was found to
be 79% and percentage of degumming is 91%.
The main advantages of the present invention are:
1. The process is simple to follow and no costly chemi
cals are used in degumming.
2. The process can be utilised to achieve any desired
degumming i.e. the rate of degumming of constituent
binding material can be kept at any desired level
without any change of constituent chemicals used for
the degumming.
3. No intermediate steps such as softening, part degumming, bleaching before actual degumming of fibre is necessary in the process.
4. The degumming can be done without pressure application or by eliminating high temperature system.

We Claim :
1. An improved process for the preparation of degummed Ramie (Boehmeria

nivea GAUD) fibres which characteriset they decorticated fibres free from

adsorbed impurities with in a bath comprising of 0.25 to 20 gm of hydrolysing agent selected from carbonate of sodium, potassium or ammonium and hydrolysis controlling agents such as 0.1 to 12 gm of ammonium or potassium persulfate 0.03 to 15 gm of sodium or hydrogen peroxide, 0.1 to 6 gm of polyoxyethylene sorbitan mono oleate 0.25 to 20 gm of sodium sulfite or mixture there of per hundred gm of fibres and the ratio of fibre to bath being kept in the range from 1:5 to 1.15 at a temperature ranging from room temperature to 140° C for a period of 1 hr to 300 hrs, removing the fibres, washing, bleaching by known methods if desired, and drying to get degummed fibres.
2. An improved process as claimed in claim 1, where in the treatment is effected
at 40 to 100° C for 1 to 8 hrs., at room temperature for 20 to 300 hrs, at 50 to
75° C for 2 to 6 hrs or at 110 to 140°C for 1 to 5 hrs.
3. An improved process as claimed in claim 1 and 2, where in the washing may
be carried out using water or acidic water (0.5 to 4% acid) or any surface
cleaning compound .
4. An improved process as claimed in claim 1 to 3 , where in the bleaching is
effected by calcium or sodium hypochlorite having 3 to 10% available
chlorine per 100 gm of fibres.
5. An improved process for the preparation of degummed Ramie (Boehmeria nivea GAUD) fibres substantially as herein described with reference to examples.

Documents:

58-del-1999-abstract.pdf

58-del-1999-claims.pdf

58-del-1999-complete specification (granded).pdf

58-del-1999-correspondence-others.pdf

58-del-1999-correspondence-po.pdf

58-del-1999-description (complete).pdf

58-del-1999-form-1.pdf

58-del-1999-form-19.pdf

58-del-1999-form-2.pdf

« Previous Patent

Next Patent »

Patent Number

226572

Indian Patent Application Number

58/DEL/1999

PG Journal Number

01/2009

Publication Date

02-Jan-2009

Grant Date

19-Dec-2008

Date of Filing

12-Jan-1999

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI-110 001, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	PRAFULLA PRAN BARUAH	REGIONAL RESEARCH LABORATORY, JORHAT 785006, ASSAM
2	AJIT KUMAR BORDOLOI	REGIONAL RESEARCH LABORATORY, JORHAT 785006, ASSAM
3	AZIZUR RAHMAN	REGIONAL RESEARCH LABORATORY, JORHAT 785006, ASSAM

PCT International Classification Number

D06M 10/6

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA