METHOD OF PRODUCING A DEODORIZING MATERIAL

Abstract: A deodorizing material used for deodorization with re­ spect to human and animal excreta by mixing at least one iron(II) or iron(III) compound selected from the group com­ prising ferrous sulfate, ferric sulfate, ferrous chloride, ferric chloride, ferrous nitrate, and ferric nitrate, in a cellulosic mat­ erial and a cellulosic formed material.

Description: The present invention relates to a method of producing a deodorizing material exhibiting an excellent capacity to provide deodorization with respect to human and animal excreta. With respect to deodorants for deodorizing human and anmimal excreta, various proposals have been made and brought into practice, but it cannot be said that an appropriate method has been employed in measuring deordorizing power. In other words, conventional methods of measuring the deodorizing power of a deodorant include one in which a gas which causes malodor, such as ammonia, methylmercaptan, or hydrogen sulfide, is used for measuring the deodorizing power of a deodorant for such a gas, and one in which a deodorant is directly added to an aqueous solution of a substance which causes malodor, such as an annomia, or methyl sulfide, so that the deodorizing power of the deodorant can be measured. Although the measurement results of the deodorizing power of deodorants obtained by these methods are sometimes to be seen, many of these results are not at all the same as those obtained by a measurement in which a deodorant is previously placed in a toilet bowl before a man or animal is allowed to defecate into the toilet bowl, and the strength of the resulting malodor is measured subjectively by the human nose. Therefore, it is not apparent whether a deodorant showing excellent results using a gas or an aqueous solution of a substance which causes malodor is actually effective as a deodorant for human and animal excreta. As a result of vigorous investigations conducted by the inventor of the present invention for the purpose of developing a deodorizing material which is capable of effectively deodorizing the odor generated by excreta of humans and animals, the inventor has developed a deodorizing material which is capable of deodorizing to such an extent that no malodor is smelt by the human nose, when a man or animal is allowed to defecate into a toilet bowl in which the deodorizing material has previously been placed. From the DE-A-2 638 957 deodorizing material for human and animal excreta is known constisting of iron (III) sulfate like F₂(SO₄)₃. This document mentioned the weak doedorant effect of iron (II). The EP-A-0 117 613 describes a disposable absorbent article incorporating agents for the treatment and prophylaxis of diaper rash and diaper dermatits. The absorbent core of a diaper can consist of piles of creped cellulose wadding. The lipase-inhibiting agents are preferably incorporated in the absorbant core substrate. In this reference FeCl₃ · 6H₂O is disclosed as well as a list of other agents. It is the object of the invention to prepare a deodorizing material exhibiting an excellent capacity to provide dedorization with respect to human and animal excreta. The method of producing a deodorizing material according to this invention is characterized in that at least one iron (II) compound selected from the group consisting of ferrous sulfate, ferrous chloride and ferrous nitrate is added to the cellulosic material or the cellulosic formed material by spraying, and oxidizing the iron (II) compound into the iron (III) compound under heating while drying the cellulosic material or the cellulosic formed material. A description is given of an example of the present invention. Example I 1. Preparation of deodorizing material : 100g of ferrous sulfate heptahydrate FeSO₄·7H₂O was dissolved in water to prepare 1000ml of an aqueous ferrous sulfate solution. 54.6g of ferric sulfate Fe₂(SO₄)3 was dissolved in water to prepare 1000ml of an aqueous ferric sulfate solution. A pulp sheet containing 30% of pulp was torn into pieces, formed into a pulp block having a diameter of about 5mm, and then dried to a water content of 20%, thus preparing 1 kg of a pulp block. Example I-1 90 ml of the above-prepared aqueous solution of ferrous sulfate heptahydrate FeSO₄·7H₂O was added to 100g of the above-prepared pulp block by spraying it with a spray and then put in an oven set at a temperature of 105°C so as to be dried to a water content of 20%, preparing a pulp-block deodorizing material. in this state, the ferrous (II) sulfate FeSO₄ has been oxidized: namely, the iron (II) compound has been changed to iron (III) compound. Example I-2 90 ml of the above-prepared aqueous solution of ferric sulfate Fe₂(SO₄)₃ was added to 100g of the above-prepared pulp block by spraying it with spray and then put in an oven set at a temperature of 105°C so as to be dried to a water content of 20%, thus preparing a pulp-block deodorizing material. (2) Measurement of odor strength of excreta Plastic buckets having covers were used as toilet bowls into which a predetermined amount of deodorizing materials used for testing deodorizing power were previously added. A panel of human subjects was asked to individually use these toilet bowls over period of 24 hours discharging both feces and urine thereinto. The covers of the toilet bowls were kept closed except during use. The panel was asked to smell the odor generated from the toilet bowls when the covers were opened immediately before and after use so that the odor strength could be subjectively measured. (3) Method of indicating odor strength of excreta The following numbers were used to classify the strength of odor sensed by the panel. Odor strength Odor strength as detected by the human nose 0 No odor sensed 1 Odor barely sensed 2 Weak odor sensed 3 Strong oder sensed (4) Results of measurement of deodorizing power of deodorizing materials The odor strength of excreta were measured in four sections into which, respectively, the deodorizing materials of the present invention (Examples I-1 and I-2), one deodorant on the market, and no deodorant had been previously placed. The results of these measurements are shown in Table 2. it can be seen from this table that the deodorizing materials of the present invention exhibit very excellent effects with respect to the deodorization of human excreta. Section Result 50g of example I-1 was used Odor strength = 0 from the start to the end of the experiment 50g of example I-2 was used Odor strength = 0 - 1 from the start to the end of the experiment Comparison example (80 ml of a liquid deodorant on the market was used) Odor strength = 0 from the start of the experiment for a period during which the amount of excreta gathered in the toilet bowl was small, but the odor strength had increased to 2 - 3 by the end of the experiment. Comparison example (no deodorant was used) Ordor strength = 1 in the state wherein only urine had collected in the toilet bowl, at the start of the experiment, but the odor strength had increased to 3 after defecation. At the end of the experiments, the excreta collected in the toilet bowl was a mixture of feces and urine in amounts of about 2 to 3 liters per toilet bowl. Example II 1. Preparation of deodorizing materials Example II-1 180ml of an aqueous solution ferrous sulfate heptahydrate FeSO₄·7H₂O prepared in Example I was added to a sheet of water absorbing material, e.g., an adult paper diaper, [specification ... absorbing pater (pulp 100%), width 300mm, length 650mm, 10 sheets, total weight 63g] by spraying it with a spray and than put in an oven set at a temperature of 105°C and dried to a water content of 15%, thus preparing an adult paper diaper as a deodorizing material. In this state, the ferrous (II) sulfate FeSO₄ has been oxidized: namely, the iron (II) compound has been changes to iron (III) compound. Example II-2 A deodorizing material was prepared in the same way as Example II-1 except that an aqueous ferric sulfate solution was used in place of the aqueous ferrous sulfate solution used in the above example II-1. 2. Measurement of odor strength of excreta The above-prepared adult paper diapers were put on a bedritten man (75 years old) at 10 a.m. and removed at 5 p.m. and the odor strength of excreta was estimated by the attendant smelling the odor generated by the paper diapers. 3. Method of indication odor strength of excreta The same method as in example I (4) Results of measurement of deodorizing power of adult paper diaper as deodorizing materials The odor strengths of excreta on three paper diapers comprising the adult paper diapers as deodorizing materials (Example II-1 and Example II-2) and an adult paper diaper which has not been treated were measured. The results are shown in Table 3. It can be seen from the table that the adult paper diapers as the deodorizing materials of the present invention exhibit very excellent effects with respect to the deodorization of human excreta. Section Result Example II-1 Odor strength = 1 (excreta of urine alone) Example II-2 Odor strength = 1 (ditto) Comparison example (untreated diaper) Odor strength = 3 (ditto) The excreta of the bedridden old man who was the subject of the test was only urine for the period of the above-mentioned time, as described above. Example III 1. Preparation of doedorizing materials Example III-1 180ml of the aqueous ferror sulfate heptahydrate FeSO₄·7H₂O prepared in example I was applied to a piece of gauze available on the marked (width 300mm, length 5000mm, weight 53g) by spraying it with a spray and then put in an oven set at a temperature of 105°C and dried to a water content of 15%, thus preparing a gauze as a deodorizing material. In this state, the ferrous (II) sulfate FeSO₄ has been oxidized: namely, the iron (II) compound has been changed to an iron (III) compound. This gauze was cut into a square having four equal sides of 30mm so as to prepare a gauze deodorizing material. Example III-2 A deodorizing material was prepared by the same method as example III-1 except that aqueous ferric sulfate solution was used in place of the aqueous ferrous sulfate heptahydrate solution FeSO₄·7H₂O used in example III-1. 2. Measurement of odor strenght of excreta The same method as in example I. 3. Method of indicating odor strength of excreta The same method as in example I. 4. Results of measurements of deodorizing power of the gauze deodorizing materials. The odor strengths of excreta in three gauze deodorizing materials comprising the gauze deodorizing materials of the present invention (Example III-1 and Example III-2) and an untreated gauze were measured in a similar manner to Example I, with the results shown in Table 4 obtained. It can be seen from this table that the deodorizing materials of the present invention exhibit very excellent effects in respect of the deodorization of human excreta. Section Result Example III-1 Odor strength = 0 - 1 from the start to the end of the experiment. Example III-2 ditto Comparison example (untreated gauze) Odor strength = 1 in the state wherein only urine had collected in the toilet bowl, at the start of the experiment, but the odor strength had increased to 3 after defecation. All the above examples relate to the cases in which odor generated from human excreta is deodorized by using an aqueous solution of ferrous sulfate or ferric sulfate, but the present invention is not limited to these cases. If an aqueous solution of ferrous chloride, ferric chloride, ferrous nitrate, or ferric nitrate is used, and if the deodorizing materials of the present invention are applied to deodorize the odor of excreta of animals such as pets, the same effects can be obtained. EFFECT OF THE INVENTION : As described above, the present invention is preferred as a method of producing a deodorizing material for deodorizing odor generated from excreta of humans or animals. In particular, the invention is effectively used to suppress of the odor from excreta of bedridden old people which has recently become a noted social problem.

Claims: A method of producing a deodorizing material comprising: adding aqueous solution of at least an iron (II) compound selected from the group consisting of ferrous sulfate, ferrous chloride and ferrous nitrate to cellulosic material or cellulosic formed material by spraying and oxidizing the iron (II) compound into the iron (III) compound under heating while drying the cellulosic material or the cellulosic formed material. A method according to claim 1, wherein wood pulp, natural cotton, or regenerated fiber is used as the cellulosic material. A method according to claim 1, wherein said cellulosic material has been formed into a sheet, a paper, powder, a block, a cotton, a cloth or clothes.

Inventors: KATO, TARO
Applicants: KITAKAMISEISHI KABUSHIKI KAISHA
Application year: 1986
Main classification: A61L9
IPC codes: A61L9, A01K1, A61L15