JPH0427864B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Industrial Application) The present invention relates to a dehumidifying and deodorizing agent, and more particularly to a novel dehumidifying and deodorizing agent that effectively adsorbs and removes one or both of moisture and odor components contained in various rooms, containers, etc. (Prior Art) Activated carbon or silica gel has been widely known as a dehumidifying and deodorizing agent used for this type of purpose. However, activated carbon or silica gel does not have a very large moisture adsorption capacity, and its dehumidifying ability or adsorption ability is extremely reduced, especially when indoor humidity or the concentration of odor components increases. Furthermore, these adsorbents do not have reversibility when moisture absorption and desorption are repeated. In other words, if an adsorbent adsorbs moisture when placed in an environment where the indoor humidity changes from low humidity to high humidity, even if the indoor environment is returned to a low humidity environment, the adsorbed moisture will not reach the value of the adsorbed moisture at low humidity. It is never dissipated and always remains partially accumulated. Therefore, if such indoor humidity cycles are repeated, the moisture contained in the adsorbent will eventually reach a saturated state, and the dehumidifying ability will rapidly decrease. (Problems to be Solved by the Invention) In view of the drawbacks of conventional activated carbon or silica gel adsorbents, the present invention has a significantly superior adsorption capacity compared to these adsorbents, and also reduces indoor humidity cycles. It is an object of the present invention to provide a dehumidifying and deodorizing agent in which moisture absorption and desorption proceed reversibly even when repeated use, and the effect is excellent in sustainability. The present inventors have been conducting intensive research on the development of new uses for zirconium compounds and have discovered that condensed zirconium phosphate is extremely suitable for the above purpose and can be used as an excellent dehumidifying and deodorizing agent. The present invention has now been accomplished. Zirconium compounds, including condensed zirconium phosphate, have been extensively studied, and as they are excellent inorganic ion exchangers, they can be used as selective adsorbents for extracting potassium from seawater and brine (Japan Sea Water). Academic journal 23 , 102
(1969), 24 , 47 (1970), 25 , 398 (1972)
)
In addition, its use in analytical chemistry, such as detection and quantification of trace components from major components, has been proposed or implemented.
No. 57-22314) has been put to practical use as a flavor preservative for tobacco flavorings. However, until now, there has been no knowledge of its use as a dehumidifying and deodorizing agent for rooms, containers, etc. (Means for Solving the Problems) That is, the present invention is a dehumidifying and deodorizing agent characterized by containing condensed zirconium phosphate as an active ingredient. The condensed zirconium phosphate (hereinafter also simply referred to as the present compound) used in the present invention includes:
Examples include one or a mixture of two or more polymers selected from zirconium tripoporinate, zirconium pyrophosphate, zirconium hexametaphosphate, zirconium trimethanephosphate, and the like. These condensed zirconium phosphates can be prepared by known methods, such as the above-mentioned Journal of the Sea Water Society of Japan or
It can be produced by the method described in Japanese Patent No. 57-22314. That is, an aqueous solution of an alkali salt of condensed phosphoric acid is added to an aqueous hydrochloric acid solution of zirconium chloride, for example, zirconium oxychloride, and stirred, and the resulting precipitate is washed with water until there is no reaction of chlorine ions in the filtrate, and then filtered. It is obtained by drying at around 80-100°C and then disintegrating it into water to a particle size of about 12-80 mesh. The resulting condensed zirconium phosphate has a slightly different structure and physical properties depending on the raw material blending ratio during production, but zirconium
A compound obtained at a blending ratio of 0.5 to 3 mol of condensed phosphoric acid per 1 mol is desirable. Further, the condensed zirconium phosphate obtained is a white granule or powder in appearance, and the result of X-ray diffraction shows no specific peak and is amorphous. However, depending on the manufacturing conditions, it forms a plate-shaped inorganic polymer with considerable directionality and a structure close to a layered structure. Therefore, unlike organic resin polymers, it is stable even at high temperatures and is stable against chemicals such as acids, alkalis, and redox agents. Table 1 shows the physical properties of various condensed zirconium phosphates used in the Examples described later. Note that the numerical values in the table may differ slightly depending on the manufacturing method.

[Table] In Table 1, the true density and packing density were measured by the measurement method specified in the JIS standard, and the specific surface area and pore volume were measured by the BET method using a pore distribution analyzer manufactured by Shimadzu Corporation. In addition, the amount of ethanol adsorption is determined by adsorbing ethanol in a sealed desiccator at a constant temperature of 22℃.
The amount of adsorption when a constant weight is reached is expressed as a percentage of the sample, and the ion exchange capacity is the value expressed as the Na exchange capacity with 0.1N-NaOH. In this specification, % is expressed as weight % unless otherwise specified. In addition, when this compound is used as a dehumidifying and deodorizing agent, the form is arbitrary, and it can be used as granules, powder, or tablets by being filled into an appropriate container. Utilizing certain properties, it can be used by mixing and molding it with various materials. In other words, this compound can be ground into a fine powder and blended into plastic sheets such as vinyl chloride resin sheets, mixed with pulp and blended into paper, mixed with paint etc. for surface coating, or used in adhesives. It can be used in various forms, such as by mixing it and applying it to wallpaper, etc. Furthermore, by utilizing the enormous adsorption capacity of this compound,
By pre-adsorbing other moisture absorbers such as calcium chloride, disinfectants such as ethyl alcohol, antifungal agents, insecticides, etc., it can be used to adjust the dehumidifying capacity and to simultaneously dehumidify and deodorize indoors and containers. It can be used for multiple purposes, such as sterilizing and preventing mold. (Function) This compound has a larger adsorption capacity for moisture or odor components than conventional adsorbents such as activated carbon or silica gel, and has excellent dehumidification or adsorption ability, especially when indoor humidity or concentration of odor components increases. Not only does moisture adsorption and desorption proceed reversibly, and even if moisture is absorbed under high humidity conditions, once the indoor humidity drops, the absorbed moisture is released again and the condition returns to its original state. Therefore, the moisture absorption ability has a unique effect of not decreasing no matter how many times the cycle of moisture absorption→moisture release→moisture absorption is repeated. The reason why this compound exhibits such a unique effect is due to the layered structure of condensed zirconium phosphate, and moisture adsorption and desorption takes place between the layers.
In addition, the interlayer has the property of swelling and contracting,
This is thought to be due to the fact that the pore volume and pore volume are extremely large, as is clear from Table 1, and that about half of the structure is composed of voids. Furthermore, this compound has the characteristic that it significantly adsorbs odor components such as ammonia and amines, which are considered to be the cause of bad odors, but does not adsorb aromatic components. The reason for this is thought to be due to the synergistic effect between the ion exchange action of the present compound and the adsorption action by the countless pores. In other words, since ammonia-based and amine-based odor components have ionic dissociation properties, adsorption reactions proceed stoichiometrically and instantaneously, and are strongly removed regardless of concentration, whereas aromatic components are generally non-ionic. It is presumed that adsorption by ion exchange and physical adsorption are difficult to be carried out because of the large number of reactive polymer compounds. If this compound is used primarily as a deodorizing agent, the deodorizing ability may decrease as well as the ion exchange ability, but in this case, the exchange ability can be easily improved by treating the used compound with a weak acid. It can be recovered and used repeatedly. (Example) The present invention will be described in more detail with reference to Examples below. Example 1 Granules obtained by sieving zirconium hexametaphosphate, zirconium tripolyphosphate, zirconium pyrophosphate, and zirconium trimetaphosphate into a range of 20 to 60 mesh each were used as samples of the present invention, and commercially available activated carbon and silica gel for moisture absorbent were used as control samples. The equilibrium moisture content adsorbed on the samples was measured when they were left in rooms with different humidity levels. That is, first, a sample was placed in a conditioned room with a constant temperature of 22°C and a humidity adjusted to 40% RH, a conditioned room adjusted to 60% RH, and a conditioned room adjusted to 83% RH, and the temperature and humidity conditions of each were adjusted. Equilibrium water content was determined for samples that had been well conditioned for about 7 days below. Separately, water was placed in a large desiccator, the sample was placed on the partition plate, and the sample was left sealed in a room at 22°C to determine the equilibrium moisture content when the weight change due to water absorption reached a constant value. For convenience, this value was taken as the equilibrium moisture content at a humidity of 100% RH. Table 2 shows the equilibrium moisture content of the sample at each humidity. The numbers in the table indicate the humidity in the conditioning room from 40%RH to 60
This is the equilibrium moisture content when increasing sequentially from %RH to 83%RH. To measure the equilibrium moisture content, place the sample in a room at a constant temperature (22℃ in this case) and constant humidity for 5 minutes.
The weight change was measured after being left for ~7 days, and the moisture content when a constant weight was reached was expressed. Moisture content is 100℃
It was calculated from the loss on drying when dried for 3 hours.

[Table] As is clear from Table 2, all of the samples of the present invention have lower equilibrium moisture content in low humidity environments of 40% RH and 60% RH than the control samples of activated carbon and silica gel. The amount of moisture increase between %RH and 60%RH is also small. However, 60%RH→
83%RH, and as it increases further from 83%RH to 100%RH, it absorbs water significantly and shows a high moisture value. Therefore, at 60% RH, which is considered the most average comfortable indoor environment, the equilibrium moisture content is low and the amount of moisture absorbed is low, but when the humidity reaches 80% RH or higher, which is the point at which people feel uncomfortable, indoor moisture is rapidly absorbed. . i.e. 60
Compared to the sample moisture increase between %RH and 100%RH, which is 7.5% for activated carbon and 7.3% for silica gel,
Zirconium hexametaphosphate reaches 35.2%, zirconium tripolyphosphate 23%, zirconium pyrophosphate 27.1%, and zirconium trimetaphosphate 18.7%, indicating extremely high moisture absorption and retention ability. Next, each sample that had been allowed to absorb moisture in a conditioning chamber where the humidity was increased sequentially as described above was changed from 83%RH to 60%RH.
→The results of measuring the equilibrium moisture content after leaving the room under the same conditions as above in a conditioned room adjusted to 40% RH and gradually lower humidity are shown in the lower column of Table 3 (the upper column shows the The results were as shown in (the numbers in the table are reproduced as they are).

[Table] From the comparison of the numerical values in the upper and lower columns shown in Table 3, the increase and decrease of moisture in the moisture absorption and moisture desorption cycles of the present invention sample group is almost the same, and the moisture that has been absorbed once is returned to almost the same amount in the moisture desorption process. completely released. Therefore, the dehumidifying ability hardly decreases even with repeated cycles of moisture absorption and desorption. On the other hand, activated carbon and silica gel, which are control samples, have strong hygroscopicity in low-humidity environments where dehumidification is not desired; It can be seen that the adsorbed moisture gradually accumulates while repeating the cycle of moisture absorption and desorption without being released, and the dehumidification ability decreases. Example 2 A sample of the present compound obtained by sieving zirconium tripolyphosphate, zirconium pyrophosphate, zirconium trimetaphosphate, and zirconium hexametaphosphate into a range of 24 to 60 meshes, and 10 g of commercially available activated carbon as a control sample were each taken, and purified water was added. and filled into glass columns. Next, open the top of the column, let the ammonia aqueous solution flow down from above the sample at a flow rate of 1.5 ml/min, collect the effluent every 10 ml, and measure the amount of ammonia in it using the normal neutralization titration method. did. The test was conducted at 1% and 3% ammonia aqueous solution concentrations.
Two types of % were tested. The results are shown in Table 4.

[Table] The effluent initially contains odorless water that does not contain ammonia. When the ammonia adsorption capacity of the sample eventually reaches saturation, the equilibrium is disrupted and ammonia is contained in the effluent. Therefore, the flow rate of the ammonia-free effluent was determined from the start of the flow, and the ammonia adsorption amount and adsorption capacity per 1 g of each adsorbent sample were calculated from this flow rate. From the results in Table 4, the samples of this compound exhibit significantly greater deodorizing power than activated carbon, and activated carbon hardly adsorbs especially in the case of highly concentrated 3% ammonia water, but all samples of this compound do not. It can be seen that the adsorption is strong and the adsorption progresses completely in a stoichiometric manner. Example 3 A fine powder obtained by crushing granules of zirconium hexametaphosphate was made of vinyl chloride resin (PVC).
Mixed with 9.8% and masticated at 180℃ for 5 minutes,
Next, after preheating at 175°C for 5 minutes, the mixture was heated under pressure at 170°C for 4 minutes (gauge pressure: 100 kg/cm ² ) and formed into a sheet to produce a soft vinyl chloride sheet with a thickness of about 1 mm. On the other hand, as a control, a vinyl chloride sheet was prepared under the same conditions without adding zirconium hexametaphosphate, and a comparative test of the deodorizing power of both sheets was conducted. That is, first, 10 ml of a 1% ammonia aqueous solution was placed in a beaker with a capacity of about 25 ml, and the beaker was placed in a 2-volume wide-mouthed glass bottle with a stopper. Add each of the above vinyl chloride sheets to this.
It was cut into squares of 14 cm x 14 cm (weighing about 20 g) and placed against the glass wall of a wide-mouth bottle to avoid direct contact with the ammonia water. The bottle was tightly capped and left indoors overnight. Next, the ammonia odor of the solutions in the beakers was compared using a sensory test method. The measurement was carried out by evaluating the strength of the odor by a sensory panel of 5 people. The results were clear; all the panelists sensed a strong ammonia odor from the aqueous solution in the beaker in the bottle containing the vinyl chloride sheet as a control, whereas the aqueous solution in the beaker in the bottle containing the vinyl chloride sheet to which this compound had been added smelled strongly. All panelists could hardly detect any ammonia odor. This result shows that this compound has an excellent deodorizing effect even when added to a vinyl chloride sheet. Example 4 Water was added to a mixture of 70 parts by weight of finely ground zirconium pyrophosphate and 30 parts by weight of pulp, and a paper sheet containing the present compound having a thickness of about 0.3 mm was produced using a paper machine. Separately, a paper sheet without the addition of zirconium pyrophosphate with a thickness of about 0.3 mm was produced using the same procedure using only pulp. In the same manner as in Example 3, place the beaker containing the ammonia aqueous solution in a wide-mouthed bottle, and place the beaker 10 cm into the bottle so that it does not come into direct contact with the ammonia aqueous solution.
Paper sheets cut to a size of 10 cm were each sealed and sealed, and the ammonia odor levels of aqueous solutions in beakers left under similar conditions were compared. The results of the odor level measurement conducted by five sensory test panelists showed that the aqueous solution in a beaker containing an additive-free paper sheet had a strong ammonia odor, and no adsorption effect by the paper sheet was observed, whereas pyrophosphoric acid All panel members judged that the aqueous beaker solution containing the zirconium-added paper sheet had no ammonia odor at all. This result shows that this compound has an excellent deodorizing effect even when added to a paper sheet. (Effects of the Invention) As explained in detail above, the dehumidifying and deodorizing agent of the present invention has a higher dehumidifying effect than conventional moisture absorbing agents.
Not only does it have a remarkable ability to absorb moisture, but it also has completely different moisture absorption characteristics, and although it absorbs little moisture in a comfortable environment with low humidity, it rapidly starts absorbing moisture in high humidity, which increases discomfort. It has a very desirable effect. Furthermore, even after repeated moisture absorption/desorption cycles, there is almost no decrease in moisture absorption ability, so it can be used for a long period of time. In addition, in terms of deodorizing effect, due to the synergistic effect of ion exchange reaction and physical adsorption, odor components can be completely deodorized instantly and stoichiometrically, but aromatic components are not removed. have. Furthermore, it is easy to use in combination with bactericides, insecticides, antifungal agents, etc., and has remarkable effects such as being able to be used as a dehumidifying and deodorizing agent for other purposes.

Claims (1)

[Scope of Claims] 1. A dehumidifying and deodorizing agent characterized by containing condensed zirconium phosphate as an active ingredient. 2. The dehumidifying and deodorizing agent according to claim 1, wherein the condensed zirconium phosphate is one or a mixture of two or more of zirconium tripolyphosphate, zirconium pyrophosphate, zirconium hexametaphosphate, and zirconium trimethanoate.