Excrement treatment material for pet and excrement treatment system for pet using the same

Abstract

To provide an excrement treatment material for pets which has improved water resistance and reduced water absorption compared to conventional materials.SOLUTION: An excrement treatment material for pets includes crushed plant-derived materials and copolymers. The copolymers include constituent units (a) derived from olefins and constituent units (b) derived from monomers having a group bindable to a group contained in the crushed materials or a group contained in the copolymers. The excrement treatment material for pets preferably includes 4 mass% or more and 15 mass% or less of the copolymer. The excrement treatment material preferably includes more than 70 mass% of the crushed materials.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pet excrement treatment material and a pet excrement treatment system using the same. [Background technology]

[0002] Various techniques have been proposed for treating excrement from pets such as dogs and cats. As a conventional technique for an excrement treatment material that allows for easy treatment, the present applicant previously proposed an excrement treatment material that contains ground plant-derived material and synthetic resin (see Patent Document 1).

[0003] Patent Document 2 describes an excrement treatment material that contains wood powder and a binder such as a polymer compound. The document also describes that the excrement treatment material described in the document has improved durability and deodorizing power.

[0004] Patent Document 3 describes animal litter containing ground plant-derived materials and synthetic resin. The document also describes that the litter described in the document can ensure a long life while preventing the generation of unpleasant odors. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-204249 A [Patent Document 2] JP 2012-147694 A [Patent Document 3] JP 2015-133932 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the excrement treatment materials described in Patent Documents 1 to 3 tend to swell or disintegrate due to absorbing urine excreted from pets, and there is room for improvement in terms of water resistance. In addition, the excrement treatment materials are designed to reduce their water absorbency after use to prevent urine from remaining on the excrement treatment materials, thereby suppressing the generation of urine-derived odors, but the excrement treatment materials described in these documents also have room for improvement in terms of water absorbency. Therefore, an object of the present invention is to provide a pet excrement treatment material which has improved water resistance and reduced water absorbency compared to conventional materials. [Means for solving the problem]

[0007] The present invention relates to a pet excrement treatment material. In one embodiment, it is preferred to include ground plant-derived materials and copolymers. In one embodiment, the copolymer comprises: A structural unit (a) derived from an olefin, and A structural unit (b) derived from a monomer having a group capable of bonding to a group contained in the pulverized material or a group contained in the copolymer. It is preferred that the compound contains

[0008] The present invention also relates to a pet excrement disposal system comprising the pet excrement disposal material and a porous member for laying the pet excrement disposal material. In one embodiment, it is preferable that the pet excrement treatment material is laid on the porous member. Effect of the Invention

[0009] According to the present invention, there are provided a pet excrement treatment material having improved water resistance and reduced water absorbency compared to conventional materials, and a pet excrement treatment system using the same. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a perspective view showing a schematic exploded state of one embodiment of a pet waste disposal system according to the present invention. [Diagram 2] FIG. 2 is a perspective view showing a schematic assembly state of one embodiment of the pet waste disposal system of the present invention. [Diagram 3] FIG. 3 is a schematic cross-sectional view of the pet waste treatment system shown in FIG. 2 taken along plane II. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will be described below based on preferred embodiments. A pet waste treatment material in this embodiment (hereinafter, simply referred to as "excrement treatment material") contains a pulverized material and a copolymer of plant-derived materials.

[0012] The excrement treatment material of this embodiment contains, as one of its constituent components, a pulverized material of plant origin (hereinafter, simply referred to as "pulverized material"). The pulverized material is derived from woody and herbaceous plants. Therefore, the pulverized material contains cellulose and hemicellulose as its constituent components. In this embodiment, by using a material derived from woody and herbaceous plants, it is possible to mask the odor caused by the fragrance of the material itself, and to exert a deodorizing effect by adsorbing odorous components to the material, and it is also possible to reduce the manufacturing cost of the excrement treatment material. Furthermore, by making the material into a pulverized material, the surface area of ​​the excrement treatment material is increased, and the deodorizing effect is exerted more effectively.

[0013] Examples of the ground material include wood flour (ground wood or bark), seed oil residue, ground grain husk, ground herb, etc. From the viewpoint of improving the water resistance and deodorizing property of the excrement treatment material, the ground plant material preferably mainly contains wood flour derived from coniferous trees such as the Cedar family, Pinaceae family, or Cupressaceae family (hereinafter also referred to as "coniferous tree-derived wood flour"). Specifically, the content of the ground material is preferably 60% by mass or more of coniferous tree-derived wood flour and 40% by mass or less of broad-leaved tree such as the Fagaceae family, Elm family, or Betulaceae family (hereinafter also referred to as "broad-leaved tree-derived wood flour"), more preferably 75% by mass or more of coniferous tree-derived wood flour and 25% by mass or less of broad-leaved tree-derived wood flour, and even more preferably 90% by mass or more of coniferous tree-derived wood flour and 10% by mass or less of broad-leaved tree-derived wood flour.

[0014] From the viewpoint of enhancing the durability of the deodorizing effect and efficiently expressing the fragrance specific to the plant-derived material, the excrement treatment material preferably contains more than 70% by mass of the pulverized material, more preferably 80% by mass or more, and even more preferably 85% by mass or more. Also, from the viewpoint of expressing water resistance, the excrement treatment material preferably contains 98% by mass or less of the pulverized material, more preferably 96% by mass or less, and even more preferably 94% by mass or less.

[0015] The shape of the pulverized material may be powder, granule, needle, plate, or an aggregate thereof. In the excrement treatment material of this embodiment, pulverized materials having the same shape may be used. Alternatively, pulverized materials having different shapes may be used in combination. From the viewpoint of reducing the load on the equipment during the production of the excrement treatment material and improving the handling, it is preferable that the pulverized material used is in powder form.

[0016] The pulverized material preferably has an average particle size within a predetermined range. This also reduces the load on the equipment during the production of the excrement treatment material and improves the ease of handling. From this viewpoint, the average particle size of the pulverized material is preferably 0.01 mm or more, more preferably 0.05 mm or more, and even more preferably 0.07 mm or more. From the same viewpoint, the average particle size of the pulverized material is preferably 5 mm or less, more preferably 3 mm or less, and even more preferably 2 mm or less.

[0017] The average particle size of the pulverized material can be measured, for example, by using a multi-stage sieve shaker by the following method. Specifically, sieves (Tokyo Screen Co., Ltd.) with nominal openings of 0.3 mm, 0.6 mm, 1 mm, 2.36 mm, and 3.35 mm are placed in this order on a multi-stage sieve shaker (Verder Scientific Co., Ltd., AS200 Basic), and 50 g of the pulverized plant material is placed on the sieve with the 3.35 mm opening located at the top stage and shaken. The shaking width is 1.2 mm, the vibration frequency is 3000 times / min, and the sieving time is 2 minutes, and the particle size distribution of the pulverized material is measured. After that, the sum of the values ​​obtained by multiplying the class values ​​between each opening by the ratio is calculated, and this is taken as the average particle size of the pulverized material. In the particle size distribution and average particle size of the pulverized material thus measured, it is preferable that the proportion of pulverized material having an average particle size of 1 mm or more and less than 2.36 mm is the largest, and it is even more preferable that this proportion accounts for 40% or more of the total by mass from the viewpoint of improving the deodorizing effect. In order to achieve such a particle size distribution, the pulverized material may be subjected to a further pulverization treatment or may be further sieved to remove pulverized material with a large diameter.

[0018] One of the features of the excrement treating material of this embodiment is that it contains a copolymer containing a predetermined structural unit (repeating unit) as one of its constituent components. Since excrement treatment materials mainly absorb urine from pets such as dogs and cats, there is a demand for materials that can suppress the generation of odors caused by urine after use. In addition, there is a demand for materials that are less likely to swell or disintegrate due to absorbed urine so that the materials can be used for a long period of time. In order to enhance the deodorizing effect, as described above, it is effective to include a plant-derived material in the excrement treatment material. However, since such materials include hydrophilic cellulose and hemicellulose, there is a problem that if the content of the materials is excessively increased in an attempt to enhance the deodorizing effect, the water resistance of the excrement treatment material decreases. The present inventors have conducted extensive research to improve this point, and have found that by using a copolymer containing the structural units (a) and (b) described below as a component of the excrement treatment material, the water resistance of the excrement treatment material is improved compared to conventional materials, even when the excrement treatment material contains a plant-derived material. Furthermore, the inventors have found that by suppressing the water absorption of the excrement treatment material, the generation of odor caused by urine remaining in the excrement treatment material can be suppressed.

[0019] Specifically, the copolymer preferably contains a structural unit (a) derived from an olefin and a structural unit (b) derived from a monomer having a group capable of bonding with a group contained in the pulverized material or a group contained in the copolymer. The copolymer need only contain the structural units (a) and (b), and does not need to consist of only the structural units (a) and (b). However, from the viewpoint of improving the water resistance of the excrement treating material, it is preferable that the copolymer consists of only the structural units (a) and (b). The copolymer may be a block copolymer or a random copolymer.

[0020] Examples of olefins used as the structural unit (a) include ethylene, propylene, butylene, 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, phenylbutadiene, 4,5-diethyl-1,3-octadiene, and 3-butyl-1,3-octadiene. The structural units derived from these olefins can be used alone or in combination of two or more. The structural units (a) derived from these olefins are hydrophobic. Therefore, by including such structural units (a) in the copolymer, the water resistance of the excrement treatment material is improved compared to conventional materials, and water absorption is suppressed. From the viewpoint of making this advantage more prominent, the olefin is preferably ethylene and propylene, and particularly preferably ethylene.

[0021] The monomer derived from the structural unit (b) is not particularly limited in type as long as it has a group capable of bonding with a group contained in the pulverized material or a group contained in the copolymer. The "group contained in the pulverized material" here refers to a functional group contained in a substance constituting the plant-derived pulverized material. Examples of such substances include cellulose and hemicellulose. The pulverized material also contains, for example, lignin, and the content of lignin in the pulverized material is less than the total content of cellulose and hemicellulose. Therefore, by selecting a monomer having a group capable of bonding with a functional group contained in cellulose and hemicellulose, it is possible to control the water resistance of the pulverized material. The term "group contained in the copolymer" as used herein refers to, for example, a group contained in the structural unit (a), a group contained in the structural unit (b), and a group contained in a structural unit other than the structural units (a) and (b) contained in the copolymer. Specific examples of groups contained in the copolymer include a carboxyl group, a group formed by dehydration condensation of two adjacent carboxylic acids (i.e., -(O=C)-O-(C=O)-), an isocyanate group, an epoxy group, an oxazoline group, and a hydroxyl group. The term "bondable group" as used herein refers to a group capable of forming a covalent bond with a group contained in the pulverized material or a group contained in the copolymer. However, the bondable group does not necessarily have to be capable of only covalent bonding, and does not preclude the group from being capable of forming a hydrogen bond in addition to a covalent bond.

[0022] The structural unit (b) has, for example, a carboxyl group, a group formed by dehydration condensation of two adjacent carboxylic acids (i.e., -(O=C)-O-(C=O)-), an isocyanate group, an epoxy group, an oxazoline group, etc. When this group is bonded to a group contained in the substance constituting the pulverized material or a group contained in the copolymer, it is possible to control the water resistance and water absorbency of the excrement treatment material. From the viewpoint of making this advantage even more pronounced, it is particularly preferable that the group is a carboxyl group or a group formed by dehydration condensation of two adjacent carboxylic acids (i.e., -(O=C)-O-(C=O)-).

[0023] The mechanism by which the excrement treating material of this embodiment improves water resistance and suppresses water absorption by using a copolymer containing structural units (a) and (b) as a constituent component of the excrement treating material is not clear, but the present inventors believe it to be the following (i) or (ii). However, the present inventors are not bound by this theory. (i) Groups in the structural unit (b) bond with hydroxyl groups in cellulose and hemicellulose, and the multiple groups resulting from the bonds are held together by the structural unit (a), thereby preventing the excrement treatment material from swelling and collapsing due to the material absorbing urine, thereby improving the water resistance of the excrement treatment material and suppressing its water absorption. (ii) The hydrophobicity of the structural unit (a) improves the water resistance of the excrement treatment material and suppresses water absorption. At the same time, the groups in the structural unit (b) bond with groups contained in the copolymer to fix the structure of the copolymer. This makes it difficult for the excrement treatment material to deform when it absorbs urine, and prevents the excrement treatment material from swelling and disintegrating.

[0024] The copolymer may contain other structural units than the structural units (a) and (b) as long as the effects of the present invention are achieved. Examples of such structural units include structural units derived from methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate. These structural units may be used alone or in combination of two or more. When the copolymer further contains these structural units, the hydrophobicity of the copolymer is increased, and the excrement treatment material can be further inhibited from absorbing urine.

[0025] In the excrement treatment material of this embodiment, the copolymer preferably contains an ethylene-acrylic acid copolymer represented by the following formula (1). By using such a copolymer, the water resistance of the excrement treatment material is improved compared to conventional materials, and water absorption is suppressed. Furthermore, the shape retention of the excrement treatment material is improved. Note that formula (1) is intended to represent the chemical structure of the repeating units constituting the copolymer and the number of the repeating units, and is not intended to represent the copolymer as a block copolymer.

[0026] [ka] (In formula (1), m1 and n1 each independently represent a number of 1 or more.)

[0027] In the copolymer represented by formula (1), the ratio of m1 to n1 (m1 / n1) is preferably within a predetermined range in order to improve the water resistance of the excrement treating material and suppress water absorption, by imparting hydrophobicity to the copolymer and by effectively bonding the group in the structural unit (b) with the group contained in the pulverized material or the group contained in the copolymer. In order to make this advantage more pronounced, the value of m1 / n1 is preferably 5 or more, more preferably 10 or more, and even more preferably 20 or more. From the same viewpoint, the value of m1 / n1 is preferably 80 or less, more preferably 60 or less, and even more preferably 40 or less.

[0028] In the excrement treatment material of this embodiment, it is also preferable that the copolymer contains an ethylene-methyl acrylate-maleic anhydride copolymer represented by the following formula (2). By using such a copolymer, the water resistance of the excrement treatment material is improved compared to conventional materials, and water absorption is suppressed. Furthermore, the shape retention of the excrement treatment material is improved. Note that formula (2) is intended to represent the chemical structure of the repeating units constituting the copolymer and the number of the repeating units, and is not intended to represent the copolymer as a block copolymer.

[0029] [ka] (In formula (2), m2, n2 and x each independently represent a number of 1 or more.)

[0030] In the excrement treating material of this embodiment, the copolymer preferably contains a copolymer represented by formula (1) or a copolymer represented by formula (2). From the viewpoint of further improving the water resistance of the excrement treating material and further suppressing the water absorption, it is particularly preferable that the copolymer contains a copolymer represented by formula (1).

[0031] The excrement treating material preferably contains a predetermined amount of the copolymer. This improves the water resistance of the excrement treating material compared to conventional materials, suppresses water absorption, and improves the shape retention of the excrement treating material. From this viewpoint, the excrement treating material preferably contains 4% by mass or more of the copolymer, more preferably 5% by mass or more, and even more preferably 6% by mass or more. From the viewpoint of improving deodorizing properties, the excrement treating material preferably contains 15% by mass or less of the copolymer, more preferably 13% by mass or less, and even more preferably 11% by mass or less.

[0032] The copolymer preferably has a melt flow rate (MFR) within a specified range. This also improves the uniform dispersion of the copolymer and improves the production efficiency when the excrement treating material is produced by the production method described below. From this viewpoint, the melt flow rate of the copolymer is preferably 0.1 g / 10 min or more, more preferably 1 g / 10 min or more, and even more preferably 5 g / 10 min or more. From the same viewpoint, the melt flow rate of the copolymer is preferably 200 g / 10 min or less, more preferably 100 g / 10 min or less, more preferably 50 g / 10 min or less, and even more preferably 40 g / 10 min or less. The melt flow rate can be measured in accordance with JIS K 7210 under conditions of a load of 2.16 kg and a temperature of 230°C.

[0033] The excrement treating material may further contain other polymers in addition to the copolymer. This makes it easier for the excrement treating material to maintain a desired shape, and further increases the productivity of the excrement treating material. Furthermore, it also makes it possible to further increase the water resistance of the excrement treating material. As the other polymer, a thermoplastic resin is preferably used. Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyamides, vinyl resins such as polyvinyl chloride and polystyrene, acrylic resins such as polyacrylic acid and polymethyl methacrylate, ethylene-propylene copolymers, polyvinyl acetate, ethylene-vinyl acetate copolymers, and polyvinyl alcohol. These polymers can be used alone or in combination of two or more.

[0034] As long as the effects of the present invention are achieved, the excrement treating material may contain other components such as antibacterial agents, colorants, etc., as necessary, in addition to the above-mentioned components. Examples of antibacterial agents include sodium benzoate, sorbic acid, potassium sorbate, didecylmethylammonium, benzalkonium chloride, polyphenols, silver, copper, etc. The content of other components is preferably 0.01% by mass or more and 0.5% by mass or less in total.

[0035] Next, a preferred method for producing the excrement treating material is described below. First, the pulverized plant-derived material, the copolymer, and, if necessary, other polymers and other components are thoroughly mixed in the above-mentioned predetermined ratio to prepare a mixture (mixing step).

[0036] In the mixing step, the copolymer may be mixed as a solid such as powder or granules, or the resin may be mixed in a pre-molten state. Components other than the copolymer may be mixed as a solid such as powder or granules. The order of mixing the raw materials in the mixing step is not particularly limited, and for example, the raw materials may be mixed all at once or may be mixed by sequential addition. When the copolymer is used as a solid, its particle size is preferably about 0.01 mm or more and 0.5 mm or less from the viewpoint of uniform mixing with other components. In any mixing method, it is preferable that the copolymer is heated to a temperature equal to or higher than the melting point during mixing.

[0037] The mixing step can be carried out using a mixer such as a paddle mixer. Specifically, for example, when a ribbon paddle mixer (manufactured by Makino Sangyo Co., Ltd.) is used as the mixer, the rotation speed is preferably 50 rpm or more, more preferably 80 rpm or more, and preferably 150 rpm or less, more preferably 120 rpm or less, and mixing can be carried out for 3 minutes to 10 minutes. When heating is performed, the heating temperature can be a temperature equal to or higher than the melting point of the copolymer described above, and is preferably 60°C to 160°C. By mixing in this way, the components can be mixed uniformly, and as a result, the desired water resistance and deodorizing performance can be easily expressed in the obtained excrement treatment material.

[0038] Next, the mixture obtained is granulated and molded using a molding machine such as a pelletizer (molding process). As a molding machine in this process, for example, an F-5 type molding machine (manufactured by Dalton Co., Ltd.) can be used. By using such a molding machine, the mixture can be compacted inside the molding machine, and as a result, a porous excrement treatment material can be produced that has a shape retention that does not easily collapse even when contacted with liquids such as urine. In the molding process, the pressure applied during compaction is preferably 9.8 MPa or more, more preferably 29.4 MPa or more, and preferably 196 MPa or less, more preferably 177 MPa or less, from the viewpoint of making it easy to granulate the obtained excrement treatment material into a desired shape and improving the shape retention after production. When a molding machine is used in the molding process, the mixture is heated (i.e., shear heat) due to mixing and compaction of the mixture. Due to the mixture being heated, the group contained in the copolymer can bond with the group contained in the substance constituting the ground product or the group contained in the copolymer. In other words, the bond of the group is caused by heating the copolymer.

[0039] The dimensions of the excrement treatment material thus produced can be changed as appropriate by changing the hole diameter of the extrusion port of the molding machine, but it is preferable that the excrement treatment material is granulated into pellets having a diameter of about 1 mm to 10 mm and a height of about 3 mm to 30 mm. In other words, it is preferable that the excrement treatment material is produced as cylindrical pellets whose height is greater than its diameter.

[0040] The above has been an explanation of the excrement treatment material. Below, a pet excrement treatment system (hereinafter, simply referred to as an "excrement treatment system") using the excrement treatment material will be explained with reference to Figs. 1 to 3.

[0041] The excrement treatment system 10 shown in Figures 1 to 3 preferably includes the excrement treatment material 20 described above and a porous member 30 for laying the excrement treatment material 20. From the viewpoint of ease of handling, the excrement treatment system 10 preferably includes an absorbent 40 for absorbing urine. From the same viewpoint, the excrement treatment system 10 preferably includes a container 50 below these, and the container 50 preferably includes a tray 52 capable of housing the absorbent 40.

[0042] The porous member 30 has a shallow tray shape and has a slat-like porous portion 31 at its bottom. The porous portion 31 is composed of a plurality of wires extending parallel to each other. There are spaces between the wires to the extent that the excrement treatment material 20 does not fall through. The porous member 30 is also configured to be detachable from the container 50.

[0043] The absorbent 40 is a sheet-like absorbent capable of absorbing liquids such as urine. The absorbent 40 may be, for example, (1) a mixture obtained by mixing an antibacterial agent and at least one of a binder, a crosslinking agent, and water with a base material mainly made of plant fiber or pulp, and molding the mixture into a sheet; (2) a mixture of clay minerals (kaolin, bentonite, zeolite, diatomaceous earth, etc.) pulverized to a predetermined particle size, water, and a binder to form a slurry, pouring the slurry into a mold of a predetermined shape, drying at a predetermined temperature until the slurry has a predetermined moisture content, and then removing the mold; or (3) a mixture of pulp and a water-absorbing polymer wrapped in a sheet such as a nonwoven fabric to form a sheet. In particular, it is preferable to use the absorbent 40 made of the constituent raw materials (1) above, in terms of improving urine absorption and facilitating handling.

[0044] The container 50 has a bottomed shape with an open top, and has a volume capable of accommodating the bottom of the porous member 30 and the absorbent 40. A substantially rectangular cutout 51 is formed on one side of the container 50, and a tray 52 can be inserted and removed from the container 50 through the cutout 51. The tray 52 is thin and has a rectangular shape in a plan view, and can be accommodated in the container 50. As shown in Fig. 3, the tray 52 accommodates the absorbent 40 that absorbs and retains excreted liquids such as urine.

[0045] 3, in the excrement treatment system 10, a porous member 30 is disposed on an absorbent 40, and an excrement treatment material 20 is laid on the porous member 30. Specifically, in the stored state shown in the figure, a container 50 is divided into upper and lower parts by the bottom of the porous member 30, and in the upper part of the container 50, the excrement treatment material 20 is laid on the porous member 30, and in the lower part of the container 50, the absorbent 40 is laid in a tray 52. ​​From the viewpoint of effectively absorbing urine, it is preferable that the absorbent 40 has a size that is approximately equal to the area in which the porous parts 31 of the porous member 30 are disposed.

[0046] When the excrement treatment material of this embodiment is used in the excrement treatment system 10 shown in Figures 1 to 3, urine excreted from a pet passes between the excrement treatment materials 20 and is quickly absorbed by the absorbent 40 laid under the porous member 30. The odorous components of the urine are deodorized by the excrement treatment material 20 and the absorbent 40 that come into contact with the urine. Furthermore, feces excreted from a pet remain on the excrement treatment material 20 or mixed with the excrement treatment material 20, and odorous components generated from the feces are adsorbed by the excrement treatment material 20, thereby achieving a deodorizing effect. The excrement treatment material 20 is highly water resistant and does not expand or collapse even when it comes into contact with urine, so the excrement treatment material can be used for a long period of time and the effort required for replacement is reduced. Even if the excrement treatment material is used for a long period of time, the material does not collapse when it is replaced or when a pet walks on the material, making it easy to handle.

[0047] The pet excrement treatment material having the above-mentioned configuration and the pet excrement treatment system using said excrement treatment material can effectively eliminate the odor of pet excrement such as urine, feces, etc. These are particularly useful as treatment materials for cat excrement, but can also be used to treat excrement from other pets, such as small animals such as dogs.

[0048] Although the present invention has been described above based on its preferred embodiment, the present invention is not limited to the above embodiment. For example, in the above embodiment, the shape of the excrement treatment material is described as being cylindrical, but the shape is not particularly limited, and it can be a polygonal prism such as a triangular prism or a square prism, or an elliptical prism, etc. The shape of the excrement treatment material can be appropriately changed by changing the shape of the extrusion port of the molding machine. EXAMPLES

[0049] The present invention will be described in more detail below with reference to examples. However, the scope of the present invention is not limited to such examples. Unless otherwise specified, "%" means "% by mass".

[0050] Example 1 Wood flour (manufactured by Dainichi Sangyo Co., Ltd., average particle size: 700 μm, 90% or more of coniferous wood flour) as a ground material of plant origin and ethylene-acrylic acid copolymer (EAA) represented by the above formula (1) (m1 / n1 value 27.7, MFR 7 g / 10 min) as a copolymer were mixed in the amounts shown in Table 1 below. Mixing was performed for 5 minutes at a rotation speed of 95 rpm using a ribbon paddle mixer (manufactured by Makino Sangyo Co., Ltd.). Then, a cylindrical pet waste treatment material having dimensions of a bottom diameter of 6 mm and a height of 13 mm was produced using a die with an extrusion port hole diameter of 6 mm and a thickness of 40 mm and a pelletizer (manufactured by Dalton Co., Ltd., F-5 type).

[0051] Example 2 Instead of the ethylene-acrylic acid copolymer (EAA), ethylene-methyl acrylate-maleic anhydride (EMA·MAA(ET)) represented by the above formula (2) (Rexpearl (registered trademark) ET530H, MFR 30g / 10min, manufactured by Japan Polyethylene Corporation) was mixed in the amounts shown in Table 1. Other than this, a pet excrement treatment material was produced in the same manner as in Example 1.

[0052] Comparative Example 1 Instead of ethylene-acrylic acid copolymer (EAA), ethylene-vinyl acetate copolymer (EVA) (Ultrathene (registered trademark) 710, MFR 18g / 10min, manufactured by Tosoh Corporation) was mixed in the amounts shown in Table 1. Other than this, a pet excrement treatment material was produced in the same manner as in Example 1.

[0053] Comparative Example 2 Instead of the ethylene-acrylic acid copolymer (EAA), an ethylene-methyl acrylate copolymer (EMA) (molar ratio of methyl acrylate to ethylene: 12.3, MFR: 18 g / 10 min) was mixed in the amounts shown in Table 1. Other than this, a pet excrement treatment material was produced in the same manner as in Example 1.

[0054] Comparative Example 3 Instead of ethylene-acrylic acid copolymer (EAA), low-density polyethylene (LDPE) (manufactured by ENEOS NUC Corporation, DNDJ-0405, MFR 25 g / 10 min) was mixed in the amounts shown in Table 1. Other than this, pet excrement treatment materials were produced in the same manner as in Example 1.

[0055] Comparative Example 4 Instead of ethylene-acrylic acid copolymer (EAA), sodium polyacrylate (AQUALIC (registered trademark) IH-G, mass average molecular weight 3 to 5 million, manufactured by Nippon Shokubai Co., Ltd.) was mixed in the amounts shown in Table 1. Other than this, a pet excrement treatment material was produced in the same manner as in Example 1.

[0056] 〔evaluation〕 The melt flow rates of the copolymers used in Examples 1 and 2 and Comparative Examples 1 to 3 were measured according to the method described above. Moreover, the mass average molecular weight of the copolymer used in Comparative Example 4 was measured according to the following method. In addition, the water absorption rate of the pet excrement treatment materials obtained in the examples and comparative examples was calculated and the water resistance was evaluated according to the following method. The results are shown in Table 1.

[0057] [Measurement of mass average molecular weight] The mass average molecular weight of the copolymer used in Comparative Example 4 was measured by the GPC method. The measurement conditions for the GPC method were: column: TSKgel G-2000H, column temperature: 40°C, mobile phase: tetrahydrofuran (THF), flow rate: 1.0mL / min, sample concentration: 10mg / 5mL-THF, injection amount: 500μL, and the mass average molecular weight was a value converted by polystyrene. The analytical sample was prepared by pretreatment, in which 10mg of the sample was dissolved in 5mL of THF (tetrahydrofuran) at room temperature for 10 minutes, and then filtered through a sintered filter with a pore size of 0.45μm.

[0058] [Calculation of water absorption rate] The water absorption rate of the pet waste treatment materials obtained in the examples and comparative examples was calculated by the following method. First, 70 g of the pet waste treatment material to be measured was placed in a mesh sieve. The mesh sieve used was a stainless steel mesh sieve manufactured by Tokyo Screen Co., Ltd., with an inner diameter of 100 mm, height of 45 mm, wire diameter of 1.12 mm, and mesh size of 2.8 mm. Next, the pet waste treatment material placed in the mesh sieve was placed in a water bath (As One, EW-100RD) with the water temperature set to 25°C, and immersed for 5 minutes. Then, the mass of the pet waste treatment material after immersion was measured, and the water absorption rate (%) was calculated from the following calculation formula (I). The results are shown in Table 1. Note that the pet waste treatment material obtained in Comparative Example 4 collapsed after immersion and became a suspension, and the water absorption rate could not be calculated. Water absorption rate (%) = 100 × [(mass [g] of pet waste treatment material after immersion) - (mass [g] of pet waste treatment material before immersion)] / (mass [g] of pet waste treatment material before immersion) (I)

[0059] [Evaluation of Water Resistance] The pet excrement treatment materials after immersion obtained in the calculation of the water absorption rate were dried at 25°C for 17 hours. Thereafter, the appearance of the pet excrement treatment materials was observed, and the water resistance was evaluated according to the following evaluation criteria. The results are shown in Table 1. It should be noted that the water resistance of the pet excrement treatment material obtained in Comparative Example 4 could not be evaluated.

[0060] [Evaluation Criteria] ◯: There were few cracks on the surface of the pet excrement treatment material, and the shape of the pet excrement treatment material was maintained. ×: Large cracks were generated on the surface of the pet excrement treatment material, and the pet excrement treatment material was disintegrated.

[0061] [Table 1]

[0062] As is clear from the results shown in Table 1, the pet excrement treatment materials obtained in each Example had reduced water absorption compared to the pet excrement treatment materials obtained in each Comparative Example, and also had improved water resistance compared to the pet excrement treatment materials obtained in each Comparative Example. [Explanation of symbols]

[0063] 10 Pet waste disposal system 20 Pet waste disposal materials 30 Porous member 40 Absorber 50 containers 51 Cutout 52 Tray

Claims

1. The present invention includes ground materials and copolymers of plant-derived materials, The copolymer is A structural unit (a) derived from an olefin, and A structural unit (b) derived from a monomer having a group capable of bonding to a group contained in the pulverized material or a group contained in the copolymer. A pet excrement treatment material comprising:

2. The pet excrement treatment material according to claim 1 , comprising the copolymer in an amount of 4% by mass or more and 15% by mass or less.

3. The pet excrement treatment material according to claim 1 or 2, comprising more than 70% by mass of the pulverized material.

4. The pet excrement treatment material according to any one of claims 1 to 3, wherein the group contained in the copolymer is a carboxyl group or a group formed by dehydration condensation of two adjacent carboxylic acids, and the group capable of bonding to said group is a carboxyl group or a group formed by dehydration condensation of two adjacent carboxylic acids.

5. 5. The pet excrement treating material according to claim 4, wherein the copolymer comprises an ethylene-acrylic acid copolymer or an ethylene-methyl acrylate-maleic anhydride copolymer.

6. A method for treating pet excrement comprising the pet excrement treatment material according to any one of claims 1 to 5 and a porous member for laying the pet excrement treatment material, A pet excrement treatment system, in which the pet excrement treatment material is laid on the porous member.

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