JP6584759B2 - Water absorption treatment material - Google Patents

Description

  The present invention relates to a water-absorbing treatment material that absorbs liquid such as human or animal excrement.

  Patent Document 1 describes an excrement treatment material which is a kind of water absorption treatment material. In this excrement disposal material, a granular core part and a covering layer part covering it are provided. The coating layer portion contains a water-absorbing polymer, and has a function of adhering excrement disposal materials that have absorbed liquids such as urine during use to solidify.

JP 2006-333773 A

  The water-absorbing polymer becomes adhesive (viscous) when absorbing liquid. Therefore, in order to increase the mass strength of the water-absorbing treatment material after use, it is preferable that the amount of the water-absorbing polymer contained in the coating layer portion is large. However, water-absorbing polymers are relatively expensive materials. Therefore, when the amount of the water-absorbing polymer used increases, the manufacturing cost of the water-absorbing treatment material increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a water-absorbing treatment material that can obtain sufficient mass strength even with a small amount of water-absorbing polymer.

  The water-absorbing treatment material according to the present invention is a water-absorbing treatment material that absorbs liquid, and has an average particle diameter of 20 μm or less contained in the granular core, the coating layer covering the granular core, and the coating layer. A weight ratio of the first water-absorbing polymer in the entire water-absorbing treatment material is 1.32% or more and 2.55% or less. .

  In this water-absorbing treatment material, the average particle diameter of the first water-absorbing polymer contained in the coating layer portion is 20 μm or less. Here, the average particle diameter means a minimum opening through which particles of 50% by weight or more can pass when a water-absorbing polymer that is an aggregate of a large number of particles is passed through a sieve. Therefore, an average particle diameter of 20 μm or less means that 50% by weight or more of particles can pass when the water-absorbing polymer is passed through a sieve having an opening of 20 μm. Thus, by finely pulverizing to an average particle size of 20 μm or less, the adhesion of the water-absorbing polymer during liquid absorption is enhanced. Therefore, in this water-absorbing treatment material, a sufficient mass strength can be obtained even though the first water-absorbing polymer contains only a small amount of 1.32% to 2.55% by weight.

  According to the present invention, it is possible to realize a water-absorbing treatment material capable of obtaining sufficient mass strength even with a small amount of water-absorbing polymer.

It is a schematic diagram which shows one Embodiment of the water absorption processing material by this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

  FIG. 1 is a schematic view showing an embodiment of a water-absorbing treatment material according to the present invention. The water-absorbing treatment material 1 is a granular water-absorbing treatment material that absorbs liquid, and includes a granular core portion 10 and a coating layer portion 20. The water absorption treatment material 1 is, for example, an excrement treatment material for pets such as cats and dogs.

  The granular core part 10 has a function of absorbing and retaining a liquid such as urine. The granular core part 10 is formed into a granular shape. Examples of the shape of the granular core 10 include a sphere, an ellipsoid, and a cylinder. Moreover, as a main material of the granular core part 10, the water retention material which has water retention performance is used. Here, the main material of the granular core part 10 means a material having the highest weight ratio in the whole material constituting the granular core part 10. Examples of the water retention material include papers.

  Any kind of paper can be used as long as it is made of pulp. As papers, for example, polyvinyl chloride wallpaper classifieds and pulp sludge can be used. The PVC wallpaper classification refers to paper obtained by classifying PVC wallpaper. That is, a material obtained by removing materials other than paper from PVC wallpaper by classification is a PVC wallpaper classified product. However, since it is difficult to completely remove materials other than paper by classification, it is normal that materials other than paper remain to some extent in the PVC wallpaper classified product.

  The granular core part 10 may contain a water-absorbing polymer (second water-absorbing polymer) having an average particle diameter larger than 20 μm. In that case, the average particle diameter of the water-absorbing polymer is preferably larger than 50 μm. Moreover, it is preferable that the weight ratio of the 2nd water absorbing polymer to the granular core part 10 is 1% or more and 5% or less.

  The covering layer portion 20 covers the granular core portion 10. The covering layer part 20 may cover the entire surface of the granular core part 10 or may cover only a part of the surface of the granular core part 10. The covering layer portion 20 has a function of adhering the water-absorbing treatment materials 1 that have absorbed liquids such as urine during use to make them solid. The weight ratio of the coating layer portion 20 to the entire water-absorbing treatment material 1 is preferably 12% or more and 15% or less.

  The coating layer portion 20 contains a water absorbent polymer 22 (first water absorbent polymer). The average particle diameter of the water-absorbing polymer 22 is 20 μm or less, more preferably 10 μm or less. As the water-absorbing polymer 22, one pulverized by a fine pulverizer such as a jet mill can be used. The weight ratio of the water-absorbing polymer 22 in the covering layer portion 20 is preferably 12% or more and 15% or less. However, the weight ratio of the water-absorbing polymer 22 to the whole water-absorbing treatment material 1 is 1.32% or more and 2.55% or less (preferably 1.32% or more and 1.70% or less).

  In this embodiment, the coating layer part 20 consists of a mixture of the water absorbing polymer 22 and a non-adhesive material. That is, the coating layer portion 20 contains no adhesive material other than the water absorbent polymer 22. The non-adhesive material is the main material of the covering layer portion 20. Here, the main material of the covering layer portion 20 refers to a material having the highest weight ratio in the entire material constituting the covering layer portion 20. As such a non-adhesive material, for example, paper powder can be used.

  Then, an example of the manufacturing method of the water absorption processing material 1 is demonstrated. This manufacturing method includes a granulation step, a covering step, a sizing step, and a drying step.

  The granulation step is a step of forming the granular core part 10. In this step, the material constituting the granular core 10 (core material) is pulverized to a predetermined size with a crusher, and the pulverized core material is put into a mixer at a predetermined ratio and mixed. After adding water, the core material is extruded and granulated by a granulator. Thereby, the granular core part 10 is obtained.

  The covering step is a step of forming the covering layer portion 20. In this process, the material (coating material) which comprises the coating layer part 20 is made to adhere to the surface of the granular core part 10 using a coating apparatus etc. The coating material contains the water-absorbing polymer 22 described above. The coating material can be applied, for example, by spraying or spraying. Thereby, the coating layer part 20 which covers the granular core part 10 is obtained.

  In the sizing step, the water-absorbing material produced in the previous step is passed through a sieve having a sieve with a predetermined size. Thereby, only the water absorption processing material which satisfy | fills a predetermined specification is extracted.

  In the drying step, the water-absorbing treatment material extracted in the previous step is dried with a dryer. The moisture content of the granular core part 10 is appropriately adjusted by drying. Thereby, while preventing the water | moisture content of the granular core part 10 from changing to the coating layer part 20 and a water absorption capability falling, it can prevent that mold | fungi etc. generate | occur | produce at the time of preservation | save of the water absorption processing material 1. FIG.

  The effect of the water absorption processing material 1 is demonstrated. In the water-absorbing treatment material 1, the average particle diameter of the water-absorbing polymer 22 contained in the coating layer portion 20 is 20 μm or less. Thus, by finely pulverizing to an average particle size of 20 μm or less, the adhesiveness of the water-absorbing polymer 22 during liquid absorption is increased. Therefore, in the water-absorbing treatment material 1, a sufficient mass strength can be obtained even though the water-absorbing polymer 22 contains only a small amount of 1.32% to 2.55% by weight.

  Further, the finely pulverized water-absorbing polymer 22 is unlikely to swell during liquid absorption. The water-absorbing polymer 22 swollen in the coating layer part 20 blocks water from the outside from reaching the granular core part 10. This means that when the water-absorbing treatment material 1 after use is poured into a flush toilet and disposed of, the water-disintegration property of the water-absorbing treatment material 1 (bonded fibers and particles are quickly separated by contact with water, This is a factor that reduces the property of dispersion. Therefore, suppressing the swelling of the water-absorbing polymer 22 contributes to improving the water disintegration property of the water-absorbing treatment material 1.

  As described above, the presence of the water-absorbing polymer 22 can be a factor that lowers the water decomposability of the water-absorbing treatment material 1, and therefore, the amount of the water-absorbing polymer 22 is preferably small in order to improve the water decomposability. From this point of view, the weight ratio of the water-absorbing polymer 22 to the entire water-absorbing treatment material 1 is preferably 1.70% or less.

  When the average particle diameter of the water-absorbing polymer 22 is 10 μm or less, the adhesiveness of the water-absorbing polymer 22 is further enhanced and the swelling is further suppressed, so that more excellent hardness and water disintegration are obtained. As described above, by reducing the particle size of the water-absorbing polymer 22, it is possible to improve the hardenability and water disintegration property. On the other hand, if an attempt is made to obtain a water-absorbing polymer 22 having a particle size that is too small, a special device or the like is required, leading to an increase in the manufacturing cost of the water-absorbing treatment material 1. From this viewpoint, the average particle diameter of the water-absorbing polymer 22 is preferably 1 μm or more.

  When the water-absorbing polymer 22 pulverized by a pulverizer is used, the water-absorbing polymer 22 having an average particle size of 20 μm or less and a small variation in particle size can be easily obtained.

  When the ratio of the coating layer portion 20 in the water-absorbing treatment material 1 is small, it is difficult to form the coating layer portion 20 with a uniform thickness on the surface of the granular core portion 10. From this viewpoint, it is preferable that the weight ratio of the coating layer portion 20 to the entire water-absorbing treatment material 1 is 12% or more. On the other hand, when the ratio of the coating layer part 20 is large, when the coating layer part 20 is formed, the coating material that cannot adhere to the surface of the granular core part 10 increases. Such an increase in surplus material is not preferable in terms of economy. From this viewpoint, it is preferable that the weight ratio of the coating layer portion 20 to the entire water-absorbing treatment material 1 is 15% or less.

  Similarly, when the ratio of the water-absorbing polymer 22 in the coating layer portion 20 is small, it is difficult to form the coating layer portion 20 with a uniform thickness on the surface of the granular core portion 10. From this viewpoint, it is preferable that the weight ratio of the water-absorbing polymer 22 to the coating layer portion 20 is 12% or more. On the other hand, from the viewpoint of reducing the amount of the water-absorbing polymer 22 used as much as possible and reducing the manufacturing cost of the water-absorbing treatment material 1, the weight ratio of the water-absorbing polymer 22 to the coating layer portion 20 may be 15% or less. preferable.

  The covering layer portion 20 is made of a mixture of the water absorbent polymer 22 and a non-adhesive material. Since the adhesive material is relatively expensive, avoiding the use of an adhesive material other than the water-absorbing polymer 22 as the material of the coating layer portion 20 contributes to a reduction in the manufacturing cost of the water-absorbing treatment material 1. On the other hand, when the coating layer portion 20 does not contain an adhesive material other than the water-absorbing polymer 22, the adhesiveness of the water-absorbing polymer 22 is particularly important in securing the mass strength of the water-absorbing treatment material 1. In this regard, in the present embodiment, sufficient mass strength is ensured by using the water-absorbing polymer 22 finely pulverized as described above.

  When the main material of the granular core part 10 is paper, the paper is a material having a low specific gravity, and thus is suitable for obtaining the water-absorbing treatment material 1 having a low specific gravity. Thus, when the water absorption processing material 1 has small specific gravity, since volume can be earned with few materials, the reduction of the manufacturing cost of the water absorption processing material 1 can be aimed at.

  When the main material of the granular core part 10 is a polyvinyl chloride wallpaper classification product, since the polyvinyl chloride wallpaper as a waste material can be utilized, the manufacturing cost of the water-absorbing treatment material 1 can be further reduced. Moreover, the polyvinyl chloride wallpaper classification has a low vinyl chloride content compared to the polyvinyl chloride wallpaper itself. For this reason, even if it is a case where it heats at the time of manufacture of the water absorption processing material 1, generation | occurrence | production of gas, such as hydrogen chloride, can be suppressed. Moreover, generation | occurrence | production of the dioxin at the time of incinerating the water absorption processing material 1 can be suppressed.

  When the water-absorbing polymer having an average particle size larger than 20 μm is contained in the granular core part 10, the water disintegration property of the water-absorbing treatment material 1 can be improved. This is because when the water from the outside reaches the granular core part 10, the water-absorbing polymer swells and thereby the collapse of the granular core part 10 is promoted. When the average particle diameter of the water-absorbing polymer is larger than 50 μm, the swelling property is increased, so that the water decomposability of the water-absorbing treatment material 1 can be further improved.

  As shown in Table 1, the weight ratio of the coating layer portion in the entire water-absorbing treatment material and the weight ratio of the water-absorbing polymer (pulverized to an average particle size of 20 μm or less by a jet mill) in the coating layer portion are changed. Thus, 48 types of samples (water absorption treatment materials) were produced. Specifically, the weight ratio of the coating layer portion was changed by 1% from 10% to 17%, and the weight ratio of the water-absorbing polymer was changed by 1% from 10% to 15%. The numerical value shown in parentheses in the table is the weight ratio of the water-absorbing polymer in the entire water-absorbing treatment material.

  In any sample, the coating layer portion was made of a mixture of the water-absorbing polymer and paper powder. For example, in the case of a sample in which the weight ratio of the water-absorbing polymer to the coating layer portion is 15% (the rightmost column in the table), the coating layer portion includes 15% by weight of the water-absorbing polymer and 85% by weight of paper dust. It consists of.

  Moreover, about any sample, the granular core part shall consist of 68 weight% PVC wallpaper classification, 29 weight% pulp sludge, and 3 weight% water-absorbing polymer. However, the water-absorbing polymer used for the granular core part is different from the above-described water-absorbing polymer used for the coating layer part, and has an average particle size larger than 50 μm. Hereinafter, in order to distinguish from this water-absorbing polymer, the water-absorbing polymer used for the coating layer portion will be referred to as “finely pulverized polymer”.

  The “mass” in the table is an evaluation of the strength of the mass of the agglomerated portion after 20 cc of 0.9% physiological saline was dropped on each sample (aggregate consisting of a large number of granular materials). It is. When the lump has sufficient lump strength that does not collapse even if the agglomerated portion is scooped up with a scoop, etc. (in particular, when the lump strength is particularly excellent, double circles), when lump strength is insufficient Is indicated by a triangle. As can be seen from the table, sufficient cohesive strength was obtained in samples in which the weight ratio of the finely pulverized polymer in the entire water-absorbing treatment material was 1.32% to 2.55%.

  “Water decomposability” is an evaluation of the water decomposability after placing the agglomerated portion in the beaker filled with water when the above-mentioned “mass” is evaluated. Circles indicate that water disintegration is sufficient to prevent clogging even when flushed in a flush toilet (a double circle indicates that water disintegration is particularly excellent), and triangles indicate that water disintegration is insufficient. It showed in. As can be seen from the table, sufficient water disintegration was obtained in a sample in which the weight ratio of the finely pulverized polymer in the entire water-absorbing treatment material was 1.70% or less.

  However, although not shown in the table, coating unevenness (unevenness) was conspicuous for the sample in which the weight ratio of the coating layer portion to the entire water-absorbing treatment material was 11% or less. That is, the thickness nonuniformity of the coating layer portion formed on the surface of the granular core portion was slightly high. The same was true for the sample in which the weight ratio of the finely divided polymer in the coating layer portion was 11% or less. Moreover, the powder residue was conspicuous in the sample in which the weight ratio of the coating layer portion in the entire water-absorbing treatment material was 16% or more. That is, there was a little excess coating material that could not adhere to the surface of the granular core. On the other hand, for samples in which the weight ratio of the coating layer portion in the entire water-absorbing treatment material is 12% or more and 15% or less and the weight ratio of the finely pulverized polymer in the coating layer portion is 12% or more and 15% or less, Almost no spots or powder was seen.

DESCRIPTION OF SYMBOLS 1 Water absorption processing material 10 Granular core part 20 Covering layer part 22 Water absorbing polymer (1st water absorbing polymer)

Claims (7)

A water-absorbing treatment material that absorbs liquid,
A granular core;
A coating layer covering the granular core;
A first water-absorbing polymer contained in the coating layer portion and having an average particle size of 20 μm or less;
A second water-absorbing polymer contained in the granular core and having an average particle size larger than 20 μm,
The water-absorbing treatment material consists only of paper and the first and second water-absorbing polymers,
Weight ratio of said first water-absorbing polymer to the total of the water treatment material state, and are less 1.70% 1.32% or more,
The water absorption treatment material, wherein a weight ratio of the second water-absorbing polymer in the granular core is 1% or more and 3% or less . The water-absorbing treatment material according to claim 1,
The water-absorbing treatment material, wherein the first water-absorbing polymer has an average particle size of 10 μm or less. In the water absorption treatment material according to claim 1 or 2,
The water absorption processing material whose weight ratio of the said coating layer part to the whole of the said water absorption processing material is 12% or more and 15% or less. In the water absorption processing material in any one of Claims 1 thru | or 3,
The water absorption processing material whose weight ratio of the said 1st water absorption polymer to the said coating layer part is 12% or more and 15% or less. In the water absorption processing material in any one of Claims 1 thru | or 4,
The coating layer portion is a water absorption treatment material made of a mixture of the first water-absorbing polymer and paper powder. In the water absorption processing material in any one of Claims 1 thru | or 5,
The main material of the granular core is a water-absorbing treatment material that is the paper. The water-absorbing treatment material according to claim 6,
The main material of the granular core is a water-absorbing treatment material that is a PVC wallpaper classified.

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