Animal litter

Abstract

This invention provides animal litter that can sufficiently suppress the generation of unpleasant odors. [Solution] The animal litter (3) of the present invention is an animal litter (3) containing a plurality of granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less. Furthermore, in the animal litter (3) of the present invention, the area of ​​the water droplet trace after the colored water droplet test for each of the above-mentioned granular materials is 12.6 mm². 2 The material is characterized by being less than 7.62, or by having a pH of deionized water less than 7.62 after a liquid passage test of the above-mentioned plurality of granular materials, or by having water-repellent properties and an uneven structure consisting of multiple protrusions.

Description

Technical Field

[0001] The present invention relates to toilet sand for animals used as a bedding material for animal toilets such as for cats and dogs.

Background Art

[0002] Conventionally, as an animal toilet for animals such as cats and dogs kept indoors, there is known one including a box-shaped toilet container with an open top and toilet sand composed of a plurality of granular materials accommodated in this toilet container. Further, as a type of animal toilet, there is known an animal system toilet including an upper container having a liquid-permeable bottom surface and a lower container disposed below this upper container and accommodating a liquid-absorbent member. In such an animal system toilet, toilet sand is accommodated in the upper container, and urine of an animal passes through between the granular materials of the toilet sand accommodated in the upper container and is absorbed by the liquid-absorbent member in the lower container.

[0003] The toilet sand accommodated in the upper container of the animal system toilet has a predetermined liquid permeability for quickly transferring the urine of the animal to the lower container. At the same time, the toilet sand has a predetermined liquid-absorbency for absorbing the urine remaining on the surface of the granular materials in order to suppress the generation of a bad odor due to the urine remaining on the surface of the granular materials.

[0004] As described above, the toilet sand used for the animal system toilet is required to have both liquid permeability and liquid absorbency, and from such a viewpoint, various toilet sands have been proposed. For example, Patent Document 1 proposes an animal toilet sand including a plurality of granular materials, wherein each of the plurality of granular materials includes a particle group made of an inorganic porous material, silica gel, and an inorganic binder for integrally fixing the particle group and the silica gel.

Prior Art Documents

Patent Documents

[0005] [[ID=二十九]]

Patent Document 1

[0006] Conventional animal litter, which uses inorganic porous materials as its main raw material, employs solidifying agents such as cement as a binder. However, solidifying agents such as cement produce calcium hydroxide during the hardening reaction, which increases the pH. As a result, when the animal litter comes into contact with urine, the decomposition of urea contained in the urine is accelerated, potentially generating ammonia, which causes unpleasant odors. Therefore, in animal litter such as that described in Patent Document 1, silica gel was mixed with the granular material to suppress the rise in pH of the granular material.

[0007] However, even with animal litter like that described in Patent Document 1, silica gel may adsorb odor-causing substances from the surrounding environment even before the litter is put into use, and the gradual release of these adsorbed odor-causing substances could generate an unpleasant odor. These odor-causing substances could include those present in the living environment as well as those present in the manufacturing environment of the silica gel and animal litter. Furthermore, even after the silica gel has adsorbed odor-causing substances from excrement such as urine, the gradual release of these adsorbed odor-causing substances could generate an unpleasant odor.

[0008] In addition to the foul odors caused by odor-causing substances adsorbed onto silica gel, conventional animal litter can still produce foul odors due to various other factors, and further improvements in odor suppression are needed.

[0009] This invention has been made in view of the above-mentioned problems, and aims to provide animal litter that can sufficiently suppress the generation of unpleasant odors. [Means for solving the problem]

[0010] The present invention includes the following embodiments.

[0011] (Aspect 1) Animal litter containing multiple granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% to 2.5% by mass, and the area of ​​the water droplet trace after a colored water droplet test is 12.6 mm². 2 Animal litter characterized by being less than [amount missing].

[0012] The animal litter of Embodiment 1 contains no silica gel at all, or if it does contain silica gel, it contains it in a low amount of 2.5% by mass or less. As a result, there are no odor-causing substances to be adsorbed by the silica gel, or the amount of odor-causing substances adsorbed by the silica gel is small, and consequently, the amount of odor-causing substances adsorbed by the silica gel released can be reduced. Thus, the animal litter of Embodiment 1 can suppress the generation of malodors caused by the release of odor-causing substances adsorbed by the silica gel.

[0013] Furthermore, with conventional animal litter, there was a risk of generating an unpleasant odor as the adsorbed odor-causing substances from urine and other excrement were gradually released after the adsorbed substances had been adsorbed. In addition, with conventional animal litter, there was a risk of generating an unpleasant ammonia odor as urine remaining on the surface of the granules evaporated. On the other hand, with the animal litter of this embodiment 1, the area of ​​the water droplet marks after the colored water droplet test was 12.6 mm². 2 Because the granular material has a small absorption surface area, urine is less likely to be absorbed by the granular material and more likely to pass through the gaps between the granular particles. As a result, in the animal litter of this embodiment 1, urine is less likely to remain on the surface of the granular material, and less ammonia is generated by the decomposition of urea contained in the urine.

[0014] As described above, the animal litter of this embodiment 1 can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, and can exhibit an excellent odor-suppressing effect.

[0015] (Aspect 2) Animal litter containing multiple granular materials, wherein each of the multiple granular materials contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less, and the multiple granular materials are characterized in that the pH of ion-exchanged water after a liquid pass-through test is less than 7.62.

[0016] The animal litter of this embodiment 2 also contains no silica gel at all, or if it does contain silica gel, it contains it in a low amount of 2.5% by mass or less. As a result, there are no odor substances to be adsorbed by the silica gel, or the amount of odor substances adsorbed by the silica gel is small, and consequently, the amount of odor substances adsorbed by the silica gel released can be reduced. Therefore, the animal litter of this embodiment 2 can also suppress the generation of malodors caused by the release of odor substances adsorbed by the silica gel.

[0017] Furthermore, conventional animal litter, even those containing silica gel, may not be able to control the pH of multiple granular materials within an appropriate range, potentially leading to the generation of ammonia, which causes unpleasant odors. In contrast, with the animal litter of this embodiment 2, the pH of the ion-exchanged water after a liquid passage test of the multiple granular materials is less than 7.62, making it less likely for ammonia, which causes unpleasant odors, to be generated even when in contact with urine. As a result, the animal litter of this embodiment 2 can suppress the generation of unpleasant odors caused by ammonia.

[0018] As described above, the animal litter of this embodiment 2 can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and malodors caused by ammonia, and can exhibit an excellent odor-suppressing effect.

[0019] (Aspect 3) Animal litter containing multiple granular materials, Each of the aforementioned plurality of granular materials contains an inorganic porous material and a solidifying agent, and is water-repellent. Each of the plurality of granular materials further contains silica gel in a content of 0.0 mass% or more and 2.5 mass% or less, and has an uneven structure composed of a plurality of convex portions, and is characterized as animal toilet sand.

[0020] The animal toilet sand of this Embodiment 3 also either does not contain silica gel at all, or even if it contains silica gel, it contains it in a low content of 2.5 mass% or less. Since there is no odor substance adsorbed to the silica gel or the amount of the odor substance adsorbed to the silica gel is small, as a result, the emission amount of the odor substance adsorbed to the silica gel can be reduced. Thereby, the animal toilet sand of this Embodiment 3 can also suppress the generation of a bad odor caused by the emission of the odor substance adsorbed to the silica gel.

[0021] In addition, in the conventional animal toilet sand, after the plurality of granular materials adsorb odor substances generated from excrement such as urine, there is a risk that the adsorbed odor substances are gradually released, generating an unpleasant bad odor. Furthermore, in the conventional animal toilet sand, there is also a risk of generating an unpleasant bad odor of ammonia caused by the evaporation of the urine remaining on the surface of the granular material. On the other hand, in the animal toilet sand of this Embodiment 3, since each of the plurality of granular materials has water repellency and an uneven structure, urine is more likely to pass between the granular materials without being absorbed by the granular materials compared to those having water repellency but no uneven structure. Thereby, in the animal toilet sand of this Embodiment 3, it is difficult for urine to remain on the surface of the granular material, and it is difficult for ammonia generated by the decomposition of urea contained in the urine to be generated.

[0022] As described above, the animal toilet sand of this Embodiment 3 can suppress the generation of a bad odor caused by the odor substance adsorbed to the silica gel and the granular material, the bad odor caused by the urine remaining on the surface of the granular material, and the bad odor caused by ammonia, and can exhibit an excellent bad odor suppressing effect.

[0023] (Embodiment 4) The animal toilet sand according to any one of the above Embodiments 1 to 3, wherein the surface of each of the plurality of granular materials is coated with a water repellent.

[0024] In the animal litter of this embodiment 4, since the surface of the granular material is coated with a water-repellent agent, urine is not absorbed by the granular material and can easily pass between the granular material, and the urine does not easily come into contact with the inside of the granular material, so that ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment 4 can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even better odor suppression effect.

[0025] (Appendix 5) The animal litter according to any one of embodiments 1 to 3, characterized in that each of the above-mentioned granular materials is coated on the surface with an ethylene-vinyl acetate copolymer.

[0026] In the animal litter of this embodiment 5, the surface of the granular material is coated with ethylene-vinyl acetate copolymer (EVA), so that urine does not easily come into contact with the inside of the granular material, and ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment 5 can more reliably suppress the generation of malodorous odors caused by ammonia and malodorous odors caused by urine remaining on the surface of the granular material, and can exhibit an even better odor suppression effect.

[0027] (Aspect 6) The animal litter according to any one of embodiments 1 to 3, characterized in that each of the above-mentioned granular materials is coated on the surface with a mixture of a water-repellent agent and an ethylene-vinyl acetate copolymer.

[0028] In the animal litter of this embodiment 6, the surface of the granular material is coated with a mixture of a water-repellent agent and EVA, so that urine is not absorbed by multiple granular materials and can easily pass between the granular materials, and urine does not easily come into contact with the inside of the granular material, so that ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment 6 can further suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even better odor-suppressing effect.

[0029] (Aspect 7) The animal litter according to any one of embodiments 1 to 6, characterized in that each of the above-mentioned plurality of granular materials contains water-repellent particles at least on its surface.

[0030] In the animal litter of this embodiment 7, since the granular material contains water-repellent particles at least on its surface, urine is not absorbed by the granular material and can easily pass between the granular material, and urine does not easily come into contact with the inside of the granular material, thus reducing the generation of ammonia caused by the decomposition of urea in the urine. Based on the above, the animal litter of this embodiment 7 can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0031] (Pattern 8) The animal litter according to any one of embodiments 1 to 7, characterized in that each of the plurality of granular materials has a Ra (calculated mean roughness) of 0.26 μm or more and 0.95 μm or less.

[0032] In the animal litter of this embodiment 8, since the granular material has a predetermined range of Ra (calculated mean roughness), urine is not absorbed by the granular material and can easily pass between the granular material, and the urine does not easily come into contact with the inside of the granular material, so that ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment 8 can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0033] (Aspect 9) The animal litter according to any one of the above embodiments 1 to 8, characterized in that each of the plurality of granular materials has an Rsm (average spacing of irregularities) of 20 μm or more and 25 μm or less.

[0034] In the animal litter of this embodiment 9, the granular material has a predetermined Rsm (average spacing of unevenness), so that urine is not absorbed by the granular material and can easily pass between the granular material, and the urine does not easily come into contact with the inside of the granular material, so that ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment 9 can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0035] (Aspect 10) The animal litter according to embodiment 3, characterized in that the uneven structure includes particles that constitute the animal litter.

[0036] The animal litter of this embodiment 10 contains granular constituent particles whose uneven structure is resistant to plastic deformation. As a result, the uneven structure does not deform easily even during use, urine is not absorbed by the granules and can easily pass between them. Furthermore, urine does not easily come into contact with the inside of the granules, and the effects of reducing the generation of ammonia produced by the decomposition of urea in urine can be sustained. Based on the above, the animal litter of this embodiment 10 can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect. [Effects of the Invention]

[0037] According to the present invention, it is possible to provide animal litter that can sufficiently suppress the generation of unpleasant odors. [Brief explanation of the drawing]

[0038] [Figure 1]Figure 1 is a schematic perspective view showing the configuration of a system toilet 1 using animal litter 3, which is a first embodiment of the present invention. [Figure 2] Figure 2 is an SEM image of the surface of granular material constituting the first embodiment of the present invention, which has been surface-treated with a water-repellent agent. [Figure 3] Figure 3 is an SEM image of the surface of granular material constituting the first embodiment of the present invention, which is surface-treated with an ethylene-vinyl acetate copolymer. [Figure 4] Figure 4 is an SEM image of the surface of granular material constituting animal litter 3, a third embodiment of the present invention, which has been surface-treated with a mixture of a water-repellent agent and an ethylene-vinyl acetate copolymer. [Figure 5] Figure 5 is an SEM image of the surface of granular material constituting the animal litter 3, a third embodiment of the present invention, which has not undergone surface treatment. [Modes for carrying out the invention]

[0039] Hereinafter, preferred embodiments of animal litter according to one embodiment of the present invention will be described in detail with reference to the drawings. In this specification, unless otherwise specified, various numerical ranges mean a range including their upper and lower limits.

[0040] In order to achieve the above objective, the inventors conducted thorough research focusing on the causes of malodor generation and found that the generation of multiple types of malodors with different causes can be suppressed by the following methods. Specifically, the inventors found that the generation of multiple types of malodors with different causes can be suppressed by at least one of the following methods: a method of reducing the silica gel content of the granular material constituting the animal litter and reducing the absorption area of ​​the granular material, and a method of reducing the silica gel content of the granular material constituting the animal litter and controlling the pH after the liquid has passed through multiple granular materials to an appropriate range. The present invention has been completed based on these findings and includes the following embodiments.

[0041] <First Embodiment> First, an animal litter 3 according to the first embodiment, which is one embodiment of the present invention, will be described in detail with reference to Figure 1.

[0042] Figure 1 is a schematic perspective view showing the configuration of a system toilet 1 using animal litter 3, which is a first embodiment of the present invention. As shown in Figure 1, the system toilet 1 comprises a cover 2, animal litter 3 of the first embodiment of the present invention, a litter container 4, a disposable waste disposal sheet 5, and a waste disposal sheet container 6.

[0043] Cover 2 is a component that forms an outer wall that serves as an enclosure to limit the entrance and exit of animals such as cats and to prevent the scattering of excrement and animal litter 3. The litter container 4 is a container for storing animal litter 3 and has a bottom surface (e.g., a grate) with a structure (e.g., a porous structure or a mesh structure) that allows urine excreted by animals to pass through. The excrement disposal sheet 5 is a disposable absorbent sheet placed below the bottom surface of the litter container 4 to absorb and retain the animal litter 3 and the urine that has passed through the bottom surface. The excrement disposal sheet container 6 is a container for storing the excrement disposal sheet 5 and is a container that can be easily inserted and removed from below the litter container 4.

[0044] The system toilet 1 shown in Figure 1 is configured such that when an animal urinates inside the cover 2, the urine passes through the animal toilet sand 3, is absorbed and held by the waste treatment sheet 5 located below the animal toilet sand 3, and then passes through the gaps between the granular material as it passes through the animal toilet sand 3.

[0045] The system toilet 1 is configured to suppress the diffusion of malodorous odors from urine by absorbing and retaining urine inside the animal toilet sand 3 and the excrement disposal sheet 5, and by covering the internal space of the excrement disposal sheet container 6, which includes the excrement disposal sheet 5, from above with the animal toilet sand 3. Therefore, in the system toilet 1, the animal toilet sand 3 has predetermined liquid permeability and liquid absorption properties, as well as predetermined adsorption properties that can adsorb odor-causing substances generated from excrement.

[0046] The animal litter 3 of this embodiment is an animal litter containing multiple granular materials, each of which contains an inorganic porous material and a solidifying agent. In this embodiment, each of the multiple granular materials further contains silica gel in an amount of 0.0% to 2.5% by mass, and the area of ​​the water droplet trace after the colored water droplet test is 12.6 mm². 2 It is less than.

[0047] Herein, in this specification, "further containing silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less" means either not containing any silica gel at all, or containing silica gel in an amount of 2.5% by mass or less.

[0048] The animal litter 3 of this embodiment contains no silica gel at all, or if it does contain silica gel, it contains it in a low amount of 2.5% by mass or less. As a result, there are no odor-causing substances to be adsorbed by the silica gel, or the amount of odor-causing substances adsorbed by the silica gel is small, and consequently, the amount of odor-causing substances adsorbed by the silica gel released can be reduced. Thus, the animal litter 3 of this embodiment can suppress the generation of malodors caused by the release of odor-causing substances adsorbed by the silica gel.

[0049] Furthermore, as mentioned above, conventional animal litter could potentially generate unpleasant odors as the granular material adsorbs odor-causing substances from urine and other excrement, and then these adsorbed odor-causing substances are gradually released. In addition, conventional animal litter could potentially generate unpleasant ammonia odors as urine remaining on the surface of the granular material evaporates. On the other hand, in the animal litter 3 of this embodiment, the area of ​​the water droplet marks after the colored water droplet test was 12.6 mm². 2 Because the granular material has a small absorption surface area, urine is less likely to be absorbed by the granular material and can easily pass through the gaps between the granular particles. As a result, the animal litter 3 of this embodiment is less likely to generate ammonia, which is produced by the decomposition of urea contained in urine.

[0050] As described above, the animal litter 3 of this embodiment can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, and can exhibit an excellent odor-suppressing effect.

[0051] In this embodiment, the area of ​​the water droplet trace after the colored water droplet test of the granular material was 12.6 mm². 2 The means of reducing the water absorption to less than the limit are not particularly limited, and known water absorption adjustment methods in this field can be employed. Specific examples include adjusting the composition of the components constituting the granular material, and / or coating the surface of the granular material with a surface treatment agent such as a water repellent, and adjusting the amount and form of the coating.

[0052] (Method for measuring the area of ​​water droplet marks after a colored water droplet test) The area of ​​the water droplet trace after a colored water droplet test can be measured as follows: (1) First, using a micropipette, measure out 5 μL of blue-colored water and drop it onto the granular sample to be measured. (2) Next, use filter paper manufactured by ADVANTEC to absorb the water droplets from the granular material. (3) Measure the size of the water droplet marks left on the surface of the granular material. At this time, consider the water droplet marks as ellipses and measure the lengths of the parts corresponding to the major axis (mm) and minor axis (mm), respectively. (4) Then, the area of ​​the water droplet trace (mm²) is calculated using the following formula. 2 Calculate ). Area of ​​water droplet trace = (major axis / 2) × (minor axis / 2) × 3.14

[0053] The granular material constituting the animal litter 3 of this embodiment will be described in detail below.

[0054] (Components of granular material) In this embodiment, the granular material constituting the animal litter 3 includes an inorganic porous material and a solidifying agent, and further contains no silica gel at all, or if it does contain silica gel, it is contained in a low amount of 2.5% by mass or less. These components will be described below.

[0055] (Inorganic porous material) The inorganic porous material, which is a component of the granular material, is not particularly limited as long as it does not hinder the effects of the present invention, and any inorganic porous material that can be used as a component of animal litter can be used. Examples of such inorganic porous materials include zeolite, sepiolite, attapulgite, diatomaceous earth, and diatomaceous shale.

[0056] The particle size of the inorganic porous material is not particularly limited, but is, for example, 400 μm or less, preferably 300 μm or less, and more preferably 200 μm or less.

[0057] Furthermore, the content of inorganic porous material in the granular material is not particularly limited as long as it does not hinder the effects of the present invention, and any content can be adopted depending on the desired odor suppression effect, strength, etc. For example, such a content can be 50 to 98% by mass. Preferably, the content of inorganic porous material in the granular material is 50 to 95% by mass, and more preferably 60 to 90% by mass. Note that the content of inorganic porous material in the granular material refers to the ratio of the mass of inorganic porous material contained in each particle of the granular material.

[0058] (Solidifying agent) The solidifying agent, which is a component of the granular material, is not particularly limited as long as it does not hinder the effects of the present invention, and any solidifying agent that can be used as a component of animal litter can be used. Examples of such solidifying agents include cement-based solidifying agents and non-cement-based solidifying agents. The cement-based solidifying agent and the non-cement-based solidifying agent may be used individually or in combination.

[0059] Cement-based solidifying agents are solidifying agents made from cement, primarily composed of calcium silicate, and harden through a reaction (hydration) with water. Examples of cement include Portland cement and white cement. By using such cement as a solidifying agent, the strength of the granular material that makes up animal litter can be increased.

[0060] Furthermore, low-alkaline cement may be used as a cement-based solidifying agent. Low-alkaline cement is a low-alkaline cement with a pH of about 11, in which the alkali metals (Na, K) contained in the cement are adjusted to a predetermined content or less. By using low-alkaline cement as a solidifying agent, the pH of the granular material that makes up the animal litter can be lowered. Lowering the pH of the granular material in this way makes it less likely for ammonia, which causes foul odors, to be generated when the granular material comes into contact with urine, thus further suppressing the generation of foul odors caused by ammonia.

[0061] On the other hand, non-cement-based solidifying agents are solidifying agents other than cement-based solidifying agents, and do not have calcium silicate as their main component. Examples of non-cement-based solidifying agents include dolomite, calcium oxide, calcium sulfate, and magnesium oxide. In particular, when a mixture of cement-based and non-cement-based solidifying agents is used as a solidifying agent, the strength of the granular material can be increased while lowering the pH, and the generation of malodorous odors caused by ammonia can be suppressed more reliably.

[0062] As a non-cement-based solidifying agent, a water-curing solidifying agent mainly composed of calcium sulfate and magnesium oxide may be used. Such water-curing solidifying agents exhibit nearly neutral properties. Furthermore, the magnesium hydroxide produced during the hardening of the solidifying agent is weakly basic. Therefore, using such a water-curing solidifying agent as a non-cement-based solidifying agent can lower the pH of the granular material, thereby more reliably suppressing the generation of malodorous odors caused by ammonia.

[0063] In a water-hardening solidifying agent mainly composed of calcium sulfate and magnesium oxide, the calcium sulfate content is preferably 50 to 95% by mass, and the magnesium oxide content is preferably 5 to 50% by mass. Here, the calcium sulfate content is the content when converted to anhydrous form.

[0064] The amount of solidifying agent in the granular material is not particularly limited as long as it does not hinder the effects of the present invention, and any amount can be adopted depending on the desired odor suppression effect and strength. For example, such an amount can be 5 to 30% by mass. The amount of solidifying agent in the granular material is preferably 10 to 25% by mass from the viewpoint of odor suppression effect and strength.

[0065] (silica gel) As described above, in this embodiment, the granular material constituting the animal litter 3 either contains no silica gel at all, or contains silica gel in a low content of 2.5% by mass or less. In other words, silica gel is any component of the granular material constituting the animal litter 3.

[0066] In this embodiment, the silica gel that can be used as a component of granular material is not particularly limited in terms of type or structure, as long as it is contained in an amount of 0.0% by mass or more and 2.5% by mass or less. Any silica gel that can be used as a component of animal litter can be used. Examples of such silica gel include commercially available silica gels such as type A silica gel, type B silica gel, and type C silica gel.

[0067] As described above, the silica gel content in the granular material is between 0.0% by mass and 2.5% by mass. When the silica gel content in the granular material is within this range, there are no odor substances adsorbed by the silica gel, or the amount of odor substances adsorbed by the silica gel is small, and as a result, the amount of odor substances adsorbed by the silica gel released can be reduced. In this way, the animal litter 3 of this embodiment can suppress the generation of malodors caused by the release of odor substances adsorbed by the silica gel.

[0068] (Other ingredients) In this embodiment, the granular material constituting the animal litter 3 may further contain any additive components other than the inorganic porous material, solidifying agent, and silica gel. Such additive components are not particularly limited, but examples include various functional components such as fragrance components, antibacterial components, diagnostic reagent components, hydrophilic components, hydrophobic components, other deodorizing components, preservative components, bactericidal components, antifungal components, and coloring components. These functional components may be used individually or in combination of two or more.

[0069] The fragrance components are not particularly limited as long as they contain aromatic compounds, and examples include alcohols such as geranol, citronellol, citral, eugenol, phenethyl alcohol, thymol, linalool, leaf alcohol, menthol, and benzyl alcohol; aldehydes such as hexyl cinnamaldehyde; and oils. The fragrance components may also further contain a dispersant for dispersing the aromatic compounds in water. Examples of dispersants include glycols and their polymers, which are liquids at room temperature (25°C).

[0070] The antibacterial component is not particularly limited as long as it can suppress the growth of bacteria, etc., and any antibacterial agent such as organic, inorganic metal, photocatalytic, or natural agents can be used. In particular, it is preferable to use an organic surfactant-type antibacterial agent because it can suppress the growth of bacteria, etc. even after the granular material has absorbed excrement such as urine.

[0071] The test reagent components are not particularly limited as long as they can detect the health status of the animal. For example, pH test reagents, protein test reagents, glucose test reagents, occult blood test reagents, urobilinogen test reagents, and other reagents that change color depending on the components of the urine can be used.

[0072] The hydrophilic component is not particularly limited as long as it can make granular material hydrophilic, and for example, surfactants can be used. Furthermore, the hydrophobic component is not particularly limited as long as it can make granular material hydrophobic, and for example, aliphatic hydrocarbons, silicone resins, fatty acids and their metal salts, polyglycols, fatty acid esters, waxes, low molecular weight polyolefins, fluorine-based resins, etc. can be used.

[0073] Other deodorizing components include those other than the inorganic porous materials and silica gel mentioned above, as long as they have a deodorizing effect. Examples include citric acid and baking soda, which neutralize ammonia odors.

[0074] Furthermore, the granular material constituting the animal litter 3 may contain activated carbon instead of the silica gel mentioned above. In other words, the granular material may contain activated carbon in addition to the inorganic porous material and solidifying agent mentioned above. When the granular material contains such activated carbon, odor-causing substances can be adsorbed by the activated carbon, and as the activated carbon is gradually oxidized, the pH of the granular material can be reduced, making it less likely for ammonia, which causes bad odors, to be generated.

[0075] (Surface coating) Furthermore, in this embodiment, the granular material constituting the animal litter 3 may have its surface coated with any surface treatment agent such as a water repellent or an ethylene-vinyl acetate copolymer.

[0076] In particular, it is preferable that the granular material constituting the animal litter 3 of this embodiment is coated on the surface with a water-repellent agent. When the surface of the granular material is coated with a water-repellent agent, urine is not absorbed by the granular material and can easily pass between the granular material, and the urine is less likely to come into contact with the inside of the granular material, thus reducing the generation of ammonia produced by the decomposition of urea in the urine. Therefore, animal litter 3 composed of such granular material can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even better odor suppression effect.

[0077] The water-repellent agent that can be used in the animal litter 3 of this embodiment is not particularly limited, and any water-repellent agent that can be used in animal litter can be used. Examples of such water-repellent agents include waxes such as paraffin wax, silicone resins, and fluororesins.

[0078] Furthermore, the granular material constituting the animal litter 3 of this embodiment may be coated on its surface with ethylene-vinyl acetate copolymer (EVA). When the surface of the granular material is coated with EVA, urine is less likely to come into contact with the inside of the granular material, and ammonia produced by the decomposition of urea in the urine is less likely to be generated. Therefore, animal litter 3 composed of such granular material can more reliably suppress the generation of malodorous odors caused by ammonia and malodorous odors caused by urine remaining on the surface of the granular material, and can exhibit an even better odor suppression effect.

[0079] Furthermore, the granular material constituting the animal litter 3 of this embodiment may have its surface coated with a mixture of the water-repellent agent and ethylene-vinyl acetate copolymer (EVA). When the surface of the granular material is coated with a mixture of the water-repellent agent and EVA, urine is less likely to be absorbed by the granular material and can easily pass between the granular material, and urine is less likely to come into contact with the inside of the granular material, thus reducing the generation of ammonia produced by the decomposition of urea contained in the urine. Therefore, animal litter 3 composed of such granular material can further suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia.

[0080] Figures 2 to 4 are SEM (scanning electron microscope) images of the surface of granular material constituting the animal litter 3 of this embodiment, which has been surface-treated with a water-repellent agent, an ethylene-vinyl acetate copolymer, and a mixture of the water-repellent agent and the ethylene-vinyl acetate copolymer, respectively. Figure 5 is an SEM image of the surface of granular material constituting the animal litter 3 of this embodiment that has not been surface-treated. Compared with the surface of the granular material shown in Figure 5, the surface of the granular material shown in Figures 2 to 4 is rougher, and in particular, the granular material surface-treated with the mixture of the water-repellent agent and the ethylene-vinyl acetate copolymer shown in Figure 4 exhibits a significant uneven structure, indicating that the presence or absence of surface treatment affects the unevenness of the granular material's surface.

[0081] Furthermore, the surface treatment agent used to coat the surface of the granular material may contain, in addition to the water-repellent agent and EVA mentioned above, any inorganic powder or additive components. Examples of such inorganic powders include talc, mica, kaolin, calcium carbonate, and aluminum oxide. On the other hand, the additive components are not particularly limited, but examples include functional components similar to those added to the granular material mentioned above, namely various functional components such as fragrance components, antibacterial components, diagnostic reagent components, hydrophilic components, hydrophobic components, deodorizing components, preservative components, bactericidal components, antifungal components, and coloring components. These functional components may be used individually or in combination of two or more.

[0082] The means for coating the surface of the granular material with the above-mentioned surface treatment agent are not particularly limited, and any coating method can be used. Examples of such coating methods include spraying the surface treatment agent onto the surface of the granular material or immersing the granular material in a surface treatment liquid.

[0083] When the surface of granular material is coated with the above-described surface treatment agent, the amount of coating is not particularly limited as long as it does not hinder the effects of the present invention, and any amount of coating can be adopted according to the desired odor suppression effect, strength, etc. Such a coating amount is, for example, 0.01 to 5.00% by mass, preferably 0.05 to 3.00% by mass, and more preferably 0.10 to 1.00% by mass, relative to the mass of the granular material.

[0084] Furthermore, the individual coating configurations of the multiple granular materials are not particularly limited as long as they do not hinder the effects of the present invention. The entire surface of each granular material may be coated with the surface treatment agent, or only a portion of the surface of each granular material may be coated with the surface treatment agent. In addition, all of the multiple granular materials may have their surfaces coated with the surface treatment agent, or only some of the surfaces may be coated with the surface treatment agent.

[0085] The multiple granular materials constituting the animal litter 3 of this embodiment each have a substantially cylindrical outer shape, but the shape of the granular materials is not limited to this shape. The shape of the granular materials can be any outer shape, such as substantially spherical or irregularly shaped granules. However, the shape of the granular materials is preferably substantially cylindrical in order to reduce scattering of granular materials when using the animal litter.

[0086] Furthermore, the size of the granular material is not particularly limited as long as it does not hinder the effects of the present invention, and any size can be adopted depending on the desired odor suppression effect, strength, etc. Examples of such granular material sizes include particle diameters in the range of 3.0 to 8.0 mm.

[0087] The particle size of the granular material is preferably in the range of 3.5 to 6.0 mm. When the particle size of the granular material is within this range, gaps are easily formed between the granular particles, and urine can easily pass between multiple granular particles. Therefore, animal litter composed of granular material with such a particle size can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, and malodors caused by urine remaining on the surface of the granular material. In addition, the particle size within the above specific range is such that it is unlikely to get stuck in the paw pads of animals such as cats, so even if an animal that is on the animal litter walks around the room, the granular material is less likely to be scattered throughout the room, and the diffusion of malodors associated with such granular material can also be suppressed.

[0088] The particle size of granular material is determined by the sieving method, that is, by the mesh size of the sieve. Specifically, the particle size of granular material refers to the particle size (mm) of the median mass, i.e., the particle size of granular material corresponding to 50% by mass, which is obtained from the particle size distribution obtained by the sieving method. The particle size distribution can be obtained by using a vibrating sieving machine equipped with multiple sieves of different mesh sizes (for example, the "AS-200" model from Retsch), sieving a predetermined mass (for example, 150g) of granular material for a predetermined time (for example, 3 minutes), and calculating the mass percentage (%) from the mass (g) of granular material remaining on each sieve.

[0089] The granular materials constituting the animal litter of the present invention can be obtained by granulating the constituent components of the granular material, which includes the inorganic porous material and solidifying agent described above, using any granulator. The granulator used for granulating granular materials is not particularly limited, but examples include compression granulators such as disc pelletizers, briquette machines, and tablet presses, as well as extrusion granulators. Furthermore, if the surface of the granulated material is to be coated with the above-mentioned surface treatment agent, the surface treatment agent can be applied to the surface of the granulated material using any application method.

[0090] <Second Embodiment> The following describes another embodiment of the present invention, namely the second embodiment of the present invention, which differs from the first embodiment described above only in the pH characteristics after liquid passage. Note that, apart from the pH characteristics after liquid passage, the second embodiment is essentially the same as the first embodiment described above, and therefore will not be explained further.

[0091] The animal litter of the second embodiment of the present invention is also an animal litter containing a plurality of granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% to 2.5% by mass. In this embodiment, the plurality of granular materials have a pH of less than 7.62 in ion-exchanged water after a liquid passage test.

[0092] The animal litter of this embodiment either does not contain silica gel, or if it does, it contains silica gel in a low amount of 2.5% by mass or less. As a result, there are no odor-causing substances to be adsorbed by silica gel, or the amount of odor-causing substances adsorbed by silica gel is small, and consequently, the amount of odor-causing substances adsorbed by silica gel released can be reduced. Therefore, the animal litter of this embodiment can also suppress the generation of malodors caused by the release of odor-causing substances adsorbed by silica gel.

[0093] Furthermore, as mentioned above, conventional animal litter, even those containing silica gel, may not be able to control the pH of the multiple granular particles within an appropriate range, potentially leading to the generation of ammonia, which causes unpleasant odors. On the other hand, in the animal litter of this embodiment, the pH of the ion-exchanged water after a liquid passage test of the multiple granular particles is less than 7.62, making it less likely for ammonia, which causes unpleasant odors, to be generated even when in contact with urine. As a result, the animal litter of this embodiment can suppress the generation of unpleasant odors caused by ammonia.

[0094] As described above, the animal litter of this embodiment can suppress the generation of malodors caused by odor-causing substances adsorbed by silica gel, as well as malodors caused by ammonia, and can exhibit an excellent odor-suppressing effect.

[0095] In this embodiment, the means for reducing the pH of the ion-exchanged water after the liquid passage test of the granular material to less than 7.62 are not particularly limited, but include, for example, adjusting the composition of the components constituting the granular material, and / or coating the surface of the granular material with the surface treatment agent described above, and adjusting the amount and form of the coating.

[0096] (Method for measuring the pH of ion-exchanged water after liquid flow test) The pH of ion-exchanged water after a liquid permeability test of granular material can be measured as follows. (1) First, fill the inside of a cylinder with an inner diameter of 84 mm and a depth of 30 mm with the granular material sample to be measured. (2) Next, approximately 20 g of deionized water, whose mass (g) has been measured in advance, is dropped from a height of 2 cm above the granular sample inside the cylinder. (3) Then, the ion-exchanged water that has passed through the cylinder and flowed out from the bottom of the cylinder is collected and its mass (g) is measured. (4) The liquid permeability (%) of the granular material is calculated by dividing the mass of the deionized water after passing through the cylinder by the mass of the deionized water before dropping and multiplying by 100. (5) Furthermore, the pH of the ion-exchanged water after passing through the cylinder is measured using any pH meter (for example, HORIBA's compact pH meter "LAQUAtwin pH-22"). The pH measurement obtained in this way is taken as the pH of the ion-exchanged water after the liquid permeability test of the granular material.

[0097] Furthermore, the animal litter of the present invention may be an animal litter of a form that combines the first and second embodiments described above. That is, this combined form of animal litter is an animal litter containing a plurality of granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0% to 2.5% by mass. In this embodiment, each of the plurality of granular materials has a water droplet area of ​​12.6 mm² after a colored water droplet test. 2 It is less than [value missing]. Furthermore, for multiple granular materials, the pH of the deionized water after the liquid passage test is less than 7.62.

[0098] The animal litter of this embodiment can achieve the effects of both the first and second embodiments described above. That is, the animal litter of this embodiment can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia.

[0099] <Third Embodiment> The following describes another embodiment of the present invention, namely the third embodiment of the present invention, which differs from the first embodiment described above only in that the granular material is water-repellent and has an uneven structure. Note that, other than the water-repellency and uneven structure, the differences from the first embodiment described above are basically the same as those of the first embodiment described above, and therefore will not be explained further.

[0100] The animal litter of the third embodiment of the present invention is also an animal litter containing a plurality of granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less. In this embodiment, the plurality of granular materials are water-repellent and have an uneven structure consisting of a plurality of protrusions. In this specification, a granular material having an uneven structure means that the Ra (calculated mean roughness) of the granular material measured according to the description herein is 0.20 μm or more and the Rsm (mean spacing between protrusions) is 20 μm or more.

[0101] The animal litter of this embodiment either does not contain silica gel, or if it does, it contains silica gel in a low amount of 2.5% by mass or less. As a result, there are no odor-causing substances to be adsorbed by silica gel, or the amount of odor-causing substances adsorbed by silica gel is small, and consequently, the amount of odor-causing substances adsorbed by silica gel released can be reduced. Therefore, the animal litter of this embodiment can also suppress the generation of malodors caused by the release of odor-causing substances adsorbed by silica gel.

[0102] In the animal litter of this embodiment, each granular material is water-repellent. In this specification, water-repellent granular material means that the water contact angle of the surface of the granular material is 90° or more. The means by which each granular material is made water-repellent are not particularly limited, and water-repellency adjustment methods known in the art can be employed. Specific examples include adjusting the composition of the components constituting the granular material, and / or coating the surface of the granular material with a surface treatment agent such as a water-repellent agent, and adjusting the amount and form of the coating.

[0103] The water contact angle on the surface of granular material can be measured as follows. (1) Prepare an aluminum ring (outer diameter: 430 mm, inner diameter: 400 mm, height: 50 mm) and granular material dried at 120°C for 60 minutes in a constant temperature and humidity chamber at 20±5°C and 65±5%RH, and leave it undisturbed for 24 hours. (2) Fill one granular material evenly into an aluminum ring, and compress the granular material, along with the aluminum ring, at a pressure of 3 MPa for 1 minute using a press with a smooth bottom surface to smooth the surface of the granular material. (3) The water contact angle of the compressed granular material is measured in accordance with JIS R 3257:1999, "Test Method for Wettability of Substrate Glass Surfaces," Section 6, the static drop method. An example of a contact angle measuring device is the CA-V automatic contact angle meter manufactured by Kyowa Interface Science Co., Ltd. The above water contact angle refers to the value 200 ms after dropping deionized water. (4) Measure the water contact angle in 20 different samples and use the average value.

[0104] As a means of ensuring that each granular material has water-repellent properties, when adjusting the composition of the components constituting the granular material, it is preferable that the granular material contains water-repellent particles at least on its surface. The water-repellent particles may be mixed into the raw materials of the granular material, or they may be sprinkled on the surface of the granular material during the formation process.

[0105] The water-repellent particles are not particularly limited and include, for example, tetrafluoroethylene resin (hereinafter referred to as "PTFE"), fluorinated pitch, fluorinated graphite, silicone powder, methyl silicone powder, and PTFE solvent dispersions. Particulate fluororesins are preferred as water-repellent particles, and PTFE is particularly preferred as particulate fluororesin. Furthermore, as long as the water-repellent resin has water-repellency properties, particles of the preferred thermoplastic resins listed below may also be used.

[0106] When using PTFE as the water-repellent particles, the preparation method is not particularly limited, but because PTFE has a high water-repellent effect and mixes well with solidifying agents, it is preferable to use low molecular weight PTFE, specifically with an average molecular weight of 500 to 5000.

[0107] The average primary particle size of the water-repellent particles is preferably 0.05 μm to 60 μm, and more preferably 0.05 μm to 30 μm.

[0108] In the animal litter of this embodiment, if the granular material contains water-repellent particles at least on its surface, urine can easily pass between the granular material without being absorbed by it, and the urine is less likely to come into contact with the inside of the granular material, thus reducing the generation of ammonia caused by the decomposition of urea in the urine. Based on the above, in the animal litter of this embodiment, when the granular material contains water-repellent particles, the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia can be suppressed more reliably, and an even better odor suppression effect can be achieved.

[0109] As a means of making each granular material water-repellent, when surface treatment of the granular material is performed, it is preferable to coat the surface of the granular material with a surface treatment agent such as a water repellent, and the means of adjusting the amount and form of the coating can be those listed in the above-mentioned explanation of "(surface coating)" as long as the water contact angle of the surface of the granular material can be made to 90° or more.

[0110] In the animal litter of this embodiment, each granular material has an uneven structure consisting of multiple protrusions. The method for forming the uneven structure in the granular material is not particularly limited. For example, the raw material for the granular material can be filled into a mold having an uneven structure on the inside and then heated to solidify it. Alternatively, the raw material for the granular material can be heated to solidify it, and then the granular material can be subjected to physical impact to shake off some of the particles constituting the animal litter, thereby forming multiple recesses in the granular material and creating multiple protrusions in the parts other than those recesses.

[0111] As described above, conventional animal litter can produce unpleasant odors when odor-causing substances from urine and other excrement are adsorbed by multiple granular particles and then gradually released. Furthermore, conventional animal litter can also produce unpleasant ammonia odors when urine remaining on the surface of the granular particles evaporates. On the other hand, in the animal litter of this embodiment, each of the multiple granular particles has both water-repellent properties and an uneven structure, making it easier for urine to pass between the granular particles without being absorbed by them, compared to litter that is water-repellent but does not have an uneven structure. As a result, in the animal litter of this embodiment, urine is less likely to remain on the surface of the granular particles, and less ammonia is generated by the decomposition of urea contained in urine.

[0112] As described above, the animal litter of this embodiment can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an excellent odor-suppressing effect.

[0113] Furthermore, as described in the first embodiment above, a textured surface can also be formed on the surface of granular materials by surface treatment. In particular, a noticeable textured surface is observed in granular materials surface-treated with a mixture of a water-repellent agent and an ethylene-vinyl acetate copolymer. This is thought to be because the ethylene-vinyl acetate copolymer is a thermoplastic resin, making it easier for particles that have been shaken off by colliding with other granular materials to re-adhere when the granular material raw material is heated and solidified while being stirred after molding.

[0114] From the viewpoint of facilitating the formation of an uneven surface on the granular material, the granular material constituting the animal litter may further contain a thermoplastic resin in addition to the inorganic porous material, solidifying agent, and silica gel. The thermoplastic resin is not particularly limited and examples include low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-α-olefin copolymer, homo, block, or random polypropylene, propylene-α-olefin copolymer, ethylene-vinyl acetate copolymer, etc. For example, if it is an ethylene-α-olefin copolymer, it can be a block copolymer or random copolymer of propylene and α-olefin. Examples of α-olefin components include ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 4-methyl-1-pentene, etc. The melting point of the thermoplastic resin is, for example, 50 to 135°C, preferably 60 to 120°C, from the viewpoint of ease of molding, ease of water repellency, and odor suppression effect of the animal litter in this embodiment.

[0115] The Ra (calculated average roughness) of the granular material constituting the animal litter in this embodiment is 0.20 μm or more, preferably 1.0 μm or less, and more preferably 0.26 μm or more and 0.95 μm or less, from the viewpoint of allowing urine to pass easily between the granular material without being absorbed by the granular material.

[0116] In this embodiment, the animal litter has granular material with a predetermined range of Ra (calculated mean roughness), so urine is not absorbed by the granular material and can easily pass between the granular materials. Furthermore, urine does not easily come into contact with the inside of the granular material, and ammonia produced by the decomposition of urea in the urine is less likely to be generated. Based on the above, the animal litter of this embodiment can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0117] The Rsm (average spacing between irregularities) of the granular material constituting the animal litter in this embodiment is 20 μm or more, preferably 30 μm or less, and more preferably 20 μm or more and 25 μm or less, from the viewpoint of allowing urine to pass easily between the granular material without being absorbed by the granular material.

[0118] In this embodiment, the animal litter has granular material with a predetermined Rsm (average spacing of irregularities), so urine can easily pass between the granular material without being absorbed by it, and urine is less likely to come into contact with the inside of the granular material, thus reducing the generation of ammonia caused by the decomposition of urea in the urine. Based on the above, the animal litter of this embodiment can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0119] In this specification, the Ra (calculated mean roughness) and Rsm (mean spacing between irregularities) of granular materials were measured using a laser displacement meter (model: KS-1000) manufactured by Keyence Corporation. Under the following measurement conditions, the surface roughness in the longitudinal direction of the granular material was measured at 10 different locations, and the average value was adopted. Measurement range: X-axis 500 μm, Y-axis 5000 μm Measurement pitch: X-axis 10 μm, Y-axis 10 μm Traveling speed: 500μm / s

[0120] In the animal litter of this embodiment, it is preferable that the uneven structure of the granular material includes particles that constitute the animal litter. As described above, the particles that constitute the animal litter refer to inorganic porous material, solidifying agent, silica gel, and any additional components.

[0121] The animal litter of this embodiment contains granular constituent particles whose uneven structure is resistant to plastic deformation. As a result, the uneven structure deforms less even during use, urine is less likely to be absorbed by the granules and can easily pass between them. Furthermore, urine is less likely to come into contact with the inside of the granules, and the effects of reducing the generation of ammonia caused by the decomposition of urea in urine can be sustained. Based on the above, the animal litter of this embodiment can more reliably suppress the generation of malodors caused by odor-causing substances adsorbed on the granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia, thereby exhibiting an even more superior odor suppression effect.

[0122] Furthermore, the animal litter of the present invention may also be an animal litter of a form that combines the third embodiment described above with the first or second embodiment described above. That is, this combined form of animal litter is an animal litter containing a plurality of granular materials, each of which contains an inorganic porous material and a solidifying agent, and further contains silica gel in a content of 0% to 2.5% by mass, has water repellency, and has an uneven structure consisting of a plurality of protrusions. In this embodiment, each of the plurality of granular materials has a water droplet area of ​​12.6 mm² after a colored water droplet test. 2 If the amount of particulate matter is less than or equal to several parts, the pH of the deionized water after the liquid passage test will be less than 7.62.

[0123] The animal litter of this embodiment can achieve the effects of both the third embodiment and the first or second embodiment described above. That is, the animal litter of this embodiment can suppress the generation of malodors caused by odor-causing substances adsorbed on silica gel and granular material, malodors caused by urine remaining on the surface of the granular material, and malodors caused by ammonia.

[0124] The animal litter of the present invention is not limited to the embodiments described above or the examples described later, and can be appropriately combined, substituted, or modified without departing from the purpose and spirit of the present invention. In this specification, ordinal numbers such as "1st," "2nd," etc., are used to distinguish the items to which they are assigned, and do not indicate the order, priority, importance, etc. of each item. [Examples]

[0125] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to such examples.

[0126] (Making animal litter) 80% by mass of zeolite powder (produced in Aiko, Miyagi Prefecture, 60-mesh pass grade, average particle size 150 μm, moisture content 7% or less) and 20% by mass of white cement (manufactured by Taiheiyo Cement Corporation) were mixed together using a leigh mixer. The resulting mixture was compressed and granulated using a disc pelletizer (manufactured by Dalton Co., Ltd.). The disc outlet opening was 5.5 mm in diameter, the disc thickness was 35 mm, and the effective length was 12 mm.

[0127] The multiple granules obtained in this manner were left at room temperature (20°C) for 72 hours to allow the cement solidification reaction to proceed. Next, the multiple granules were dried using a rotary kiln dryer until the final moisture content was 10% or less.

[0128] A surface treatment agent consisting of a mixture of 50% by mass of a water-repellent wax-based resin (TH-44, manufactured by Nikka Chemical Co., Ltd.) and 50% by mass of ethylene-vinyl acetate copolymer (EVA) was applied to multiple dried granular materials in an amount equal to 1.00% by mass relative to the mass of the granular materials. During application, the surface treatment agent was sprayed onto the multiple dried granular materials while stirring and mixing them.

[0129] Next, the multiple granular materials whose surfaces were coated with the above-mentioned surface treatment agent were sieved using a sieve with a mesh size of 10 mm x 10 mm to remove granular materials larger than a predetermined size. Then, they were sieved again using a sieve with a mesh size of 5 mm x 10 mm to remove granular materials and powders smaller than a predetermined size, obtaining multiple granular materials within a predetermined size range. In this way, the animal litter sand of Example 1 was obtained.

[0130] Except for changing the composition of the granular material and the surface coating (type of surface treatment agent) as shown in Table 1 below, animal litter for Examples 2-6 and Comparative Examples 1-10 were obtained in the same manner as in Example 1. Commercially available Type C silica gel (from Qingdao, China) was used.

[0131] For the animal litter obtained in Examples 1-6 and Comparative Examples 1-10, the area of ​​water droplet marks, liquid permeability, and pH of the deionized water after the colored water droplet test were measured. In addition, the surface roughness (Ra (calculated mean roughness) and Rsm (mean spacing between irregularities)) was measured for each example and comparative example of animal litter, and the presence or absence of water repellency and irregularity was confirmed. Furthermore, the odor-suppressing effect of each example and comparative example of animal litter on urine was evaluated according to the following <Sensory Evaluation Method for Urine Odor>. The measurement results and sensory evaluation results are shown in Table 1 below. Note that the presence or absence of water repellency and irregularity is indicated by ○ if present and × if absent.

[0132] <Method for sensory evaluation of urine odor> (1) A sample of the animal litter to be evaluated is placed inside a cylinder with an inner diameter of 84 mm and a depth of 30 mm, which is set up on a slatted platform. (2) Drop 20 mL of actual cat urine onto the sample of animal litter packed inside the cylinder in three separate drops. The total volume dropped will be 60 mL. (3) Place the sample after urine dripping into a 700 mL airtight container. (4) Smell the sample in the container and evaluate it based on the following criteria for urine odor intensity and pleasantness / unpleasantness. The average of 20 evaluation scores will be used for the evaluation.

[0133] (Evaluation criteria for urine odor intensity) 1: A barely perceptible odor or no odor at all 2: A smell so weak that you can identify what it is. 3: An odor that can be easily detected 4: Strong odor 5: An extremely strong smell

[0134] (Criteria for evaluating the degree of pleasure or displeasure) 1: Very comfortable 2: Comfortable 3: Neither comfortable nor uncomfortable 4: Unpleasant 5: Very unpleasant

[0135] [Table 1]

[0136] As shown in Table 1, all of the animal litter samples in Examples 1 to 6 of the present invention had low evaluation scores for urine odor intensity and pleasantness / unpleasantness, indicating that they could sufficiently suppress the generation of malodors. On the other hand, all of the animal litter samples in Comparative Examples 1 to 10 had high evaluation scores for at least one of the urine odor intensity and pleasantness / unpleasantness, indicating that they could not sufficiently suppress the generation of malodors. [Explanation of symbols]

[0137] 1. System toilet 2 Covers 3. Animal litter 4. Toilet litter container 5. Waste disposal sheet 6. Container for waste disposal sheets

Claims

1. Animal litter containing multiple granular materials, Each of the aforementioned plurality of granular materials comprises an inorganic porous material and a solidifying agent. It further contains silica gel in an amount of 0.0% to 2.5% by mass, and the area of ​​the water droplet trace after the colored water droplet test is 12.6 mm². ２ Animal litter characterized by being less than [amount missing].

2. Animal litter containing multiple granular materials, Each of the aforementioned plurality of granular materials contains an inorganic porous material and a solidifying agent, and further contains silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less. The aforementioned plurality of granular materials are characterized in that the pH of the ion-exchanged water after the liquid passage test is 7.62 or less, making it a litter for animals.

3. Animal litter containing multiple granular materials, Each of the aforementioned plurality of granular materials contains an inorganic porous material and a solidifying agent, and is water-repellent. Animal litter, characterized in that each of the aforementioned plurality of granular materials further contains silica gel in an amount of 0.0% by mass or more and 2.5% by mass or less, and has an uneven structure consisting of a plurality of protrusions.

4. The animal litter according to any one of claims 1 to 3, characterized in that each of the plurality of granular materials has a surface coated with a water-repellent agent.

5. The animal litter according to any one of claims 1 to 3, characterized in that each of the plurality of granular materials has its surface coated with an ethylene-vinyl acetate copolymer.

6. The animal litter according to any one of claims 1 to 3, characterized in that each of the plurality of granular materials has its surface coated with a mixture of a water-repellent agent and an ethylene-vinyl acetate copolymer.

7. The animal litter according to any one of claims 1 to 6, characterized in that each of the plurality of granular materials contains water-repellent particles at least on its surface.

8. The animal litter according to any one of claims 1 to 7, characterized in that each of the plurality of granular materials has a Ra (calculated mean roughness) of 0.26 μm or more and 0.95 μm or less.

9. The animal litter according to any one of claims 1 to 8, characterized in that each of the plurality of granular materials has an Rsm (average spacing of irregularities) of 20 μm or more and 25 μm or less.

10. The animal litter according to claim 3, characterized in that the uneven structure includes particles that constitute the animal litter.

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