Title of Invention	"A PROCESS FOR THE PREPARATION OF OXYGEN SCRUBBER"
Abstract	This invention relates to a process for the preparation of oxygen scrubber comprising in the steps of 40 to 60 gms of iron powder is dry mixed with 0.1 gm to 2.0 gm of metal halide, characterized in that is; spreading of mixed iron powder and metal halide with adhesive onto the base; drying the base at a temperature between 25 to 36°C, under vacuum.

Full Text

FIELD OF INVENTION The present invention relates to the process for preparation of oxygen scrubber. PRIOR ART It is known that the preservation of food and foodstuffs and like is necessary, because such products cor tain food or micro-organisms etc. or the reductive substances. The microorganisms, bacteria, eumycetes etc cause deterioration of the food and foodstuffs etc and hence disturb the preservation of food and foodstuffs etc. Such microorganisms. eumycetes, mold, insects, bacteria etc. grow in the presence of oxygen. Their growth takes place at the cost of quality of food and foodstuffs etc. The reductive substances, generally, cause discoloration of malfunction due to their oxidation which also takes place in (he-presence of oxygen. The oxygen is absorbed from the atmospheric air. The atmospheric air, and hence the atmospheric oxygen plays an important role in metabolic activity of respiring bodies like fresh fruits and vegetables. The fruits on exposure to air, and hence oxygen get overripe for a short period by their respiration activity and this over-ripening decreases their value as a commodity. Similarly, the vegetable, fishes etc. get moldy or rotten, on exposure to air, and hence their -value as commodity is reduced. The food and processed foodstuffs containing oil, such as peanuts, cakes, potatoes, potato chips etc. get oxidised due ' to oxidation of their oil, on exposure to atmospheric air. This oxidation of oil, results in formation of oxidised and peroxides, which inturn deteriorate the tasti of the food and foodstuffs and even sometimes results in toxic products, hence resulting in total rejection of food and foodstuffs, which is highly undesirable in today'p populated world. Reduction in oxygen concentration has been observed to extend the . shelf life of fruits, vegetables, food, foodstuffs and like, as it results in reduced respirators levels, thereby restricting the metabolic activity leading towards ripening/ageing of the fruits and vegetables etc. In cases of oxidation susceptible processed foods, oxidative deterioration leads towards discolouration and off-flavour development which are not desirable from aesthetic and nutritional point of view. The reduced concentration of oxygen can restrict or prevent these deteriorative changes, such as oxidation of oils of food and food stuffs, proliferation of fungi, bacteria and insects etc., over-ripenning of fruits and vegetables etc. and extend the shelf life of fruits i vegetables, fishes, foods and processed food stuffs and like. Therefore, various means, such as, cold storage, freest1 storage, refrigeration, v ace urn packaging, inert qaas purging methods and/or use of insect ic. idais, ftingic idals and lucid additives like antioxidants etc to protect such damages to foods and foodstuffs and thus to enhance the shelf 1 if & of foods and food stuffs have been proposed in the prior art. These m e t h a d s have various d i 3 a d v ant a g e s o f t; h e :i. i • o ui n . Such as, the storage methods require huge and expensive apparatus and complicated operation, which in turn restrict their application to small scales. The use of insecticides and fungicides is also limited, due to their high taxi city even to humiin beings. The use of food additives, like the ant iox idants etc: is also controversial now a days, due to their recently noticed adverse effects on humane beings. The vacuum packaging for total elimination of air, and hence of oxygen, from the atmosphere of container:-:; and bag-3 carrying food and foodstuffs is exteremeiy difficult and highly expensive. The total sealing of the containers an>:.l bags to create vacuum or to replace air by an inert gas 1 i I-1 nitrogen, is practically not feasible. The major disadvantage of vacuum package or iix'i'l. 'ijos, purging method is that the complete elimination of a .1 r In order to overcome the disadvantage and drawbacks ofj such methods, various oxygen scrubber1.; have been cle ve I on •••! and various packaging means thereo* have- been proposed. Such known oxygen scrubbers are generally ascorbic aciu and/or salts of ai-icorhic acid based, enzyme catalysed, palladium based or iron based. The ascorbic acid and/or ascorbic acid salt based oxygen scrubbers have major disadvantage of having poor. f lowab i 1 i ty, which limits their packaging by automatic' machines, and further such scrubbers are uneconomical as during sealing, part of such scrubber s adhere to the sealed portion of the packagings. The enzyme catalysed oxygen scrubber comprise of glucose oxidase and catalase enzymes. The glucose oxictase oxidises glucose to gluconic acid and hydrogen peroxide and the catalase dissociates hydrogen peroxide. The disadvantage of such oxygen scrubber is the requirement; of glucose oxidase and catalase enzymes, which are costlier and hence make the product expensive, and further the stability of enzymes is suspected without immobilisation, which is a highly specialised area where high capitals investments art;-required. Therefore, the enzyme catalysed oxygen scrubbers could not be used widely. The palladium based oxygen scrubbers have disadvantage of requirement of filling of hydrogen gas. At least QV, of hydrogen gas is required to be filled in the pack. The major disadvantage of requirement of hydrogen is that, the hydrogen gas is highly inflammable and explosive in nature. The iron based oxygen scrubber known in the prior art. generally comprises of iron in powder form, which results in poor flowability of such scrubbers and hence the disadvantage of ascorbic acid based oxygen scrubbers as described herein above. In addition, the iron based oxygen scrubbers comprising of iron in powder form have risk of leakage of iron from ;l!ti? i pack/sachet, if the seal of later is broken while in uThis leakage of iron ppwder and of any such oxygen scrubbtn increases the risk of poisoning of food and food stuffs with such oxygen scrubber, and hence limiting the use of such scrubbers, particularly in powder form. In order to overcome, the disadvantages of powder fa:-,it oxygen scrubbers, and attempt has been made to graru.il ate *;ha oxygen scrubber to use them iin tablet form. The particulate or granular form of oxygen scrubbers as known in the prior art are generally prepared by b 1 e\ id :i i ->\.\ granulation or extruding granulation or f'luidized bud g r anu 1 a t :i. on a r rolling g r an u 1 a t i r.m o r s t i r r i n g q i' an u i a t i on or grinding granulation technique, which in turn calls.". i or heavy machinery and hence making the process uneconomical. The granular form of oxygon scrubbers are gent? rally used a f t e r c o a t i n g . S u c h c o a 11 n 1:4 c a lls for c o v c i • i n g t h (.' part or whole of the particulate or granular oxygen 3crubber with fine particles of coating matt?rial, which in turn 15 required to be carried out in G-shaped blender or V-shaped blender or coating pan or concrete mixer. This requirement. again makes the product expensive and process inconvenient. The further, disadvantage of such coating requirement is that, the particle size of coatincj materials is required to be controlled precisely. The another drawback of such known oxygen scrubbers is that, generally they comprise of a filler, such as activated carbon or carbon black etc., which in turn necessitates. tho use of binder in order to convert the powder form of oxygen scrubber into granular form. The disadvantage of using the binder as one o i' t he-const i tuent in known oxygen scrubbers is that, it '.binder'1 lowers the oxygen absorbing property of the oxygen scrubber The known methods of preparation of granular oxygen i scrubber particularly' of iron-based type, camp rise:? 01 mixing and blending of various ingredients dr reaction or iron powder in aqueous solution of metal halides or spraying of solution of metal halide on the iron pieces. Such known methods are practically inconvenient to be performed. Alternatively, known oxygen scrubbers are prep-aryd from carbonate of iron preferably ferrous carbonate, which itse!.' is difficult to be prepared due to requirement u f tot;;:1.! elimination of air from the reaction environment. IH addition such scrubbers require control of ispDc. i f .i c riurf ac!.> area, which has direct relation to its function cap ahi1itv and incorporation of coagulant nrwc ip i t at e thi? ferrous carbonate. The packaging of oxygen scrubber is also r s'? 11:i .a. i. ., as its exposure to air or oxygen will result in utility ol the owygen scrubber itself before it is really ream .red to bs used or being used. The known packaging techniques and packag'•><: ar generally uneconomical and requires high clan of instrumentat ion.> The known such packs are generally formed with two or more of permeable sheets, with or without impermeable sheet / or film, such as, an air p-ermeable sheet, impregnated sheet. low softening point film, high softening point film, porou: composite film, composite film, reinforcing sheet. OBJECTS OF THE INVENTION A primary object of the present invention is to propose an oxygen scrubbers and a process of preparation thereof which obviates the disadvantages adn drawbacks of the prior art. Another object of this invention to propose an oxygen scrubber in the form of a sheet and hence eliminates all disadvantages of powder form scrubbers, such as of poor flowability, wastage during packaging, leakage on sudden breakage of seal of pack etc. Still another object of this invention is to propose an oxygen scrubber, which is free from filler and binder, and hence avoid the disadvantages of use of fillers and binders. Yet another object of this invention is to propose an oxygen scrubber which does not require any coating material and hence eliminates the disadvantages of the requirement of the coating material. A further object of the present invention is to propose an oxygen scrubber and a process for preparation and for package thereof, which are convenient to be prepared and are highly economical. A still further object of the present invention is to propose an oxygen scrubebr having optimal oxygen scrubbing efficacy and leave residual oxygen less than 4% within 2 to 4 days and hence avoids anaerobic condition for the fresh fruits, vegetables etc, and further avoids formation of alcohol in the fruits and vegetables. BRIEF DESCRIPTION AND PREFERRED EMBODIMENTS OF THE INVENTION According to this invention there is provided a process for the preparation of oxygen scrubber comprising in the steps of: i) 40 to 60 gms of iron powder in the form of reduced iron blue dust is dry mixed with 0.1 gm to 2.0 gm of metal halide, characterized in that is; ii) spreading of mixed iron powder and metal halide sodium chloride with non synthetic adhesive onto the base wherein said base is a pulp base; iii) drying the base at a temperature between 25 to 36°C, under vacuum. In accordance to the preferred embodiment of the present invention the iron powder is reduced iron blue dust or electrolytic iron or reduced iron, preferably reduced iron blue dust o specific grade and having certain specific gravity. In accordance to the preferred embodiment of this invention the metal halide is most preferably sodium chloride. The base is a solid object capable to provide a hard surface to the iron powder and the adhesive and inturn is capable of forming the firm boding with the spreaded iron powder, metal halide and the adhesive. In accordance with a preferred embodiment, the base is mostly is a pulp base. The adhesive is preferably non-synthetic adhesive. In accordance with a preferred embodiment, the adhesive is either directly applied onto the base or is first mixed with iron powder and metal halide and then applied onto the base followed by drying the base. The individual sh@et-form oxygen scrubber is individually packed in air permeable film, which in turn is packed either individually or in a group of two or more in air and water impermeable film, preferably in aluminium foil-polyethylene laminated pouches. The iron powder is of specific grade, such as reduced iron blue dust or electrolytic iron or reduced iron, preferably reduced iron blue dust and having specific gravity of 1.5 to 5.0, preferably of 1.9 to 3.7, more preferably of 2.9 to 3.05. The metal halide is most preferably sodium chloride and is taken between 0.1 gm to 2.0 gms. The iron powder is taken between 40 to 60 gms for each gm of metal halide. The base is a solid object capable of providing the hard surface to the adhesive and mixture of iron powder and the metal halide, or to the mixture of adhesive, iron powder and metal halide,a s the case may be, as the case may be, as stated herein above. The selected base is preferably pulp base and inturn- is capable of forming the firm bonding with the spreaded iron powder, metal halide and tfie adhesive. The base with spreaded iron powder, metal halide and adhesive is dried at the temperature of 25 to 36°C, under vacuum preferably of 550 to 650 mm Hg till the water content is obtained between 2 to 10%. In accordance to the preferred embodiment of the packaging of the present invention the individual sheet-form oxygen scrubber after drying under vacuum as described above is preferably first individually packed in air permeable film, which in turn is then packed either individually or in a group of two or more in air and water impermeable film, preferably in aluminium toil-polyethylene laminated pouches. I CLAIM; 1. A process for the preparation of oxygen scrubber comprising in the steps of: i) 40 to 60 gms of iron powder in the form of reduced iron blue dust is dry mixed with 0.1 gm to 2.0 gm of metal halide, characterized in that is; ii) spreading of mixed iron powder and metal halide sodium chloride with non synthetic adhesive onto the base wherein said base is a pulp base; iii) drying the base at a temperature between 25 to 36°C, under vacuum. 2. A process as claimed in claim 1 wherein the said base is dried under vaccum preferably at 550 to 650 mm Hg. 3. A process as claimed in claim 1 wherein said base is dried till water content is between 2 to 10% by weight. 4. A process for the preparation of oxygen scrubber substantially as herein described.

Documents:

677-del-1997-abstract.pdf

677-del-1997-claims.pdf

677-del-1997-correspondence-others.pdf

677-del-1997-correspondence-po.pdf

677-del-1997-description (complete).pdf

677-del-1997-form-1.pdf

677-del-1997-form-19.pdf

677-del-1997-form-2.pdf

677-del-1997-form-3.pdf

677-del-1997-gpa.pdf