JP2009167371A - Solidifying agent for solidifying waste fluid containing body fluid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solidifying agent which sufficiently solidifies whole of a waste fluid quickly by solving problems of conventional solidifying agents that solidification is not sufficient, for example, the collected waste fluid containing body fluid is not solidifies rapidly, or partially solidifies but contains unsolidified parts, etc. <P>SOLUTION: The solidifying agent for the waste fluid containing the body fluid consists of a water-absorbing resin (A) and silica (B), wherein the content of the (A) is 98.00-99.95% and the (B) is 0.05-2.00% based on the weight sum of the (A) and the (B). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a solidifying agent effective for solidifying waste liquid containing body fluid generated in a hospital or the like.

Conventionally, waste fluid containing body fluids such as blood, amniotic fluid and other body fluids generated at the time of surgery in hospitals, maternity hospitals, body fluids such as sputum from patients and waste fluids that washed the stomach, etc. are collected in plastic containers etc. Often incinerated. However, if it is processed in a liquid state, the sealing property of the container may be insufficient, or secondary infection may occur due to scattering of waste liquid including body fluid due to damage of the container during transportation. Therefore, it is desired to treat the waste liquid after it is solidified. For example, a medical waste liquid treatment agent comprising two types of water-absorbing resin (Patent Document 1) or a water-absorbing material comprising a water-absorbing resin is water-disintegrating paper or A gelled material for medical waste that is wrapped in a water-soluble film (Patent Document 2) has been proposed.
JP 2002-119853 A JP-A-6-216

However, the conventional solidifying agent for solidifying the waste liquid containing body fluid does not solidify immediately even if the solidifying agent is added to the recovered waste liquid, or the part that is partially solidified but not partially solidified remains. There was a problem that solidification was insufficient. In addition, after adding the solidifying agent, it is possible to mix the waste liquid and the solidifying agent well by mixing with a stir bar or shaking the container to improve the solidification. It is not preferable because of increased properties.
An object of the present invention is to provide a solidifying agent capable of quickly and sufficiently solidifying a waste liquid containing a body fluid collected in a container without the risk of secondary infection.

  The characteristic of the solidifying agent for solidifying the waste liquid containing the bodily fluid of the present invention comprises the water absorbent resin (A) and silica (B), and is based on the total weight of (A) and (B) ( The gist is that the content of A) is composed of 98.00 to 99.95% and the content of (B) is 0.05 to 2.00%.

  The solidifying agent of the present invention can quickly and sufficiently solidify the waste liquid containing body fluid without the risk of secondary infection. In particular, even when used in waste fluids containing body fluids collected in plastic containers, etc., there is no risk of secondary infection, and waste fluids can be solidified quickly and sufficiently. Can be prevented.

As the water absorbent resin (A), any water-insoluble water absorbent resin can be used, and examples thereof include the following (1) to (5).
(1) One or more monomers (b) selected from a polysaccharide such as starch or cellulose (I), a water-soluble monomer and / or a monomer that becomes water-soluble by hydrolysis, and a crosslinking agent ( C) as an essential component, and if necessary, a water-absorbing resin obtained by hydrolysis (Japanese Patent Laid-Open No. 52-25886, Japanese Patent Publication No. 53-46199, Japanese Patent Publication No. 53-46200) And the like described in Japanese Patent Publication No. 55-21041).
Examples of (a) include pentaerythritol, diglycerin, sorbitol, xylitol, mannitol, dipentaerythritol, glucose, fructose, sucrose, cellulose, CMC, starch and the like.
Examples of (b) include radically polymerizable water-soluble monomers containing a carboxyl group, a sulfonic acid group, and a phosphoric acid group, and salts thereof.
As a radically polymerizable water-soluble monomer having a carboxyl group, for example, unsaturated mono- or poly (divalent to hexavalent) carboxylic acid [(meth) acrylic acid (meaning acrylic acid and / or methacrylic acid; hereinafter the same). Maleic acid, maleic acid monoalkyl (carbon number 1-9) ester, crotonic acid, sorbic acid, itaconic acid, itaconic acid monoalkyl (carbon number 1-9) ester, itaconic acid glycol monoether, Cinnamic acid, citraconic acid, citraconic acid monoalkyl (carbon number 1 to 9) ester, etc.] and their anhydrides [maleic anhydride, etc.].

Examples of the radically polymerizable water-soluble monomer having a sulfonic acid group include aliphatic or aromatic vinyl sulfonic acids (vinyl sulfonic acid, allyl sulfonic acid, vinyl toluene sulfonic acid, styrene sulfonic acid, etc.), 2-hydroxy- 3- (meth) acryloxypropylsulfonic acid, (meth) acrylic alkylsulfonic acid [sulfoethyl (meth) acrylic acid, sulfopropyl (meth) acrylic acid etc.], (meth) acrylamide alkylsulfonic acid [2-acrylamido-methylpropane Sulfonic acid] and the like.
Examples of the radically polymerizable water-soluble monomer having a phosphoric acid group include (meth) acrylic acid hydroxyalkyl phosphate monoester [2-hydroxyethyl (meth) acryloyl phosphate, phenyl-2-acryloyloxyethyl phosphate, etc.] Etc.
Examples of the salt of the radically polymerizable water-soluble monomer containing a carboxyl group, a sulfonic acid group, and a phosphoric acid group include the above-mentioned carboxyl group, sulfonic acid group, and salt of the phosphorus water-soluble monomer [alkali metal salt (sodium salt, Potassium salts, etc.), alkaline earth metal salts (calcium salts, magnesium salts, etc.), amine salts or ammonium salts, etc.].

  Other (b) include amide group-containing monomers [(meth) acrylamide, etc.], tertiary amino group-containing monomers [dimethylaminoethyl (meth) acrylamide, etc.], quaternary ammonium base-containing monomers [the above-mentioned tertiary amino group-containing Quaternized monomers (things quaternized with a quaternizing agent such as methyl chloride, dimethyl sulfate, benzyl chloride, dimethyl carbonate, etc.)], epoxy group-containing monomers [glycidyl (meth) acrylate, etc.], etc. It is done.

Two or more of these may be used in combination.
Among these, from the viewpoint of water retention ability, a radically polymerizable water-soluble monomer having a carboxyl group and a salt thereof are preferable, more preferably an unsaturated mono- or polycarboxylic acid and a salt thereof, and particularly preferably (meth) acrylic. Acids and their salts.

As (c), (c-1) a crosslinking agent having two or more radically polymerizable unsaturated groups, (c-2) (a), at least one functional group capable of reacting with the functional group of (b) And a compound having at least one radically polymerizable unsaturated group, a compound having two or more functional groups capable of reacting with the functional groups of (C-3) (a) and (b), and the like.
Specific examples of (C-1) include N, N′-methylenebisacrylamide, ethylene glycol (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and glycerin (di or tri) acrylate. , Trimethylolpropane triacrylate, triallylamine, triallyl cyanurate, triallyl isocyanurate, tetraallyloxyethane, pentaerythritol triallyl ether and the like.

Specific examples of (C-2) include hydroxyethyl (meth) acrylate, N-methylol (meth) acrylamide, glycidyl (meth) acrylate and the like.
Specific examples of (C-3) include polyhydric alcohols (ethylene glycol, diethylene glycol, glycerin, propylene glycol, trimethylolpropane and the like), alkanolamines (diethanolamine and the like), polyamines (polyethyleneimine and the like), and the like.
Two or more of these crosslinking agents may be used in combination. Of these, (C-1) is preferable from the viewpoint of water absorption, and more preferably N, N′-methylenebisacrylamide, ethylene glycol diacrylate, trimethylolpropane triacrylate, tetraallyloxyethane, penta. Erythritol triallyl ether and triallylamine.
The ratio of (a), (b) and (c) and the method for producing the water absorbent resin are not particularly limited. ;

(2) Polymerized (i) and (b) above (hydrolyzate of starch-acrylonitrile graft polymer), hydrolyzate of cellulose-acrylonitrile graft polymer, etc.);
(3) Cross-linked product of (i) above (cross-linked product of carboxymethyl cellulose, etc.);
(4) Copolymers of (b) and (c) above {Partially hydrolyzed cross-linked polyacrylamide, cross-linked acrylic acid-acrylamide copolymer, cross-linked polysulfonate (cross-linked sulfonation) Polystyrene, etc.), cross-linked polyacrylate / polysulfonate copolymer, saponified vinyl ester-unsaturated carboxylic acid copolymer (Japanese Patent Laid-Open Nos. 52-1489 and 52-27455) And the like), cross-linked polyacrylic acid (salt), cross-linked acrylic acid-acrylic ester copolymer, cross-linked isobutylene-maleic anhydride copolymer, cross-linked polyvinyl pyrrolidone, and Cross-linked carboxylic acid-modified polyvinyl alcohol, etc.}; and

(5) Self-crosslinked polymer of (b) (self-crosslinked polyacrylate, etc.).
Two or more water-absorbing resins exemplified above may be used in combination.
Among these water-absorbing resins, from the viewpoint of water absorption, among those exemplified as (1) and (4), a crosslinked polyacrylamide copolymer, a crosslinked polyacrylic acid (salt), and a crosslinked polymer are preferable. Acrylic acid-acrylic acid ester copolymer, and crosslinked carboxylic acid-modified polyvinyl alcohol.

  In the method for producing a water-absorbent resin, a water-containing gel-like polymer is obtained by polymerizing a radically polymerizable water-soluble monomer, adding a crosslinking agent at an arbitrary stage, and polymerizing. Thereafter, drying, pulverization, and a method of obtaining a highly water-absorbent resin by adjusting the particle size as necessary are exemplified.

In the production of the water-absorbent resin, the polymerization method is not particularly limited, and examples thereof include an aqueous solution polymerization method, reverse phase suspension polymerization method, spray polymerization method, photoinitiated polymerization method, and radiation polymerization method.
A preferred polymerization method is a method of performing aqueous solution polymerization and reverse phase suspension polymerization using a radical polymerization initiator. In this case, the type and amount of radical polymerization initiator and radical polymerization conditions are not particularly limited. In these polymerization systems, various additives, chain transfer agents (such as thiol compounds) and the like may be pulverized as necessary.

  As a drying method, a normal method may be used. For example, a drum dryer, a parallel flow band dryer (tunnel dryer), an aeration band dryer, a jet flow (nozzle jet) dryer, a box type hot air dryer, an infrared dryer. Etc. are used. The heat source is not particularly limited. These dryers can be used in combination.

The apparent density (g / cm ³ ) of the water-absorbent resin (A) is not particularly limited, but when it is put into the waste liquid, it does not shift to the upper layer part and the solidification is sufficient. From the viewpoint of sufficient solidification, 0.40 to 0.60 is preferable, more preferably 0.45 to 0.58, and still more preferably 0.47 to 0.56. The apparent density is measured by a method using a specific gravity cup (based on JIS Z2504: 2000).

  The weight average particle diameter of the water absorbent resin (A) is not particularly limited, but is preferably 106 to 750 μm, more preferably 150 to 600 μm, and particularly preferably 200 to 500 μm. Within this range, the solidification property is further improved.

  The weight average particle size was measured using a low-tap test sieve shaker and a standard sieve (JIS Z8801-1: 2000), Perry's Chemical Engineers Handbook, 6th edition (McGlow Hill Book Company, 1984, 21). Page). That is, the JIS standard sieves are 1000 μm, 850 μm, 710 μm, 500 μm, 425 μm, 355 μm, 250 μm and 150 μm from the top, and the order of the saucer, or 500 μm, 355 μm, 250 μm, 150 μm, 125 μm, 75 μm and 45 μm, and the saucer from the top. Combine in order. About 50 g of the measured particles are put in the uppermost screen and shaken for 5 minutes with a low-tap test sieve shaker. Weigh the measured particles on each sieve and the pan, and calculate the weight fraction of the particles on each sieve by taking the total as 100% by weight. Use this value as a logarithmic probability paper [horizontal axis is sieve aperture (particle size ), After the vertical axis is plotted on the weight fraction], a line connecting the points is drawn to obtain a particle diameter corresponding to the weight fraction of 50% by weight, and this is defined as a weight average particle diameter.

Further, the smaller the content of fine particles, the better the absorption performance. From the viewpoint of absorption performance, the content of fine particles of 106 μm or less (preferably 150 μm or less) in the total particles is preferably 3% by weight or less, more preferably 1 % By weight or less.
The content of the fine particles can be determined using a plot created when determining the weight average particle diameter.

  The water absorption amount of the water absorbent resin (A) may be the water absorption amount of a normal water absorbent resin, and the water absorption amount (g / g) with respect to physiological saline is 30 to 80 from the viewpoint of water retention capability and ease of production. Preferably, it is 40-75, More preferably, it is 50-70 next more preferably. In addition, the water absorption of (A) is measured by the same method as the water absorption of the solidifying agent described later.

  The water absorbent resin (A) is preferably in the form of particles from the viewpoint of dispersibility when charged into the waste liquid. The shape of the particles of (A) is not particularly limited, and examples thereof include irregularly crushed shapes, flake shapes, pearl shapes, rice grains, and granulated products thereof. Among these, from the viewpoint of the water absorption rate, a granulated product of pearl-like particles and an irregularly crushed shape are preferable.

The water-absorbent resin (A) may be surface-crosslinked with a known surface-crosslinking agent (for example, JP-A-2003-225565) as necessary. By surface crosslinking, the solidification property is further improved.
The water absorbent resin (A) can be easily obtained in the same manner as known methods (for example, JP-A No. 2003-225565).

  Silica (B) is not particularly limited, and examples thereof include fumed silica described in “Production and application of high-purity silica” (CMC Corporation, issued on September 13, 1999). Among them, finely divided silica is preferred by hydrophobizing silanol groups on the surface of fine powdery hydrophilic silica by covalently modifying alkyl groups and the like, and hydrophobic by modifying by covalently bonding methyl groups. Finely divided silica is more preferable because moderate hydrophobicity can be obtained.

Examples of the method of covalently bonding a methyl group to a silanol group on the surface include a method of reacting a silanol group with dimethyldichlorosilane or the like. The number of methyl groups covering the surface of silica (B) can be controlled by the amount of dimethyldichlorosilane to be reacted. The number is not particularly limited, but in view of adjusting the hydrophobicity of (B), and when the solidifying agent is added to the waste liquid, the solidifying property is sufficient without being shifted to the lower layer, and the solidifying agent is input to the waste liquid. From the standpoint that the solidification property is sufficient without shifting to the upper layer portion, 1.0 to 4.0 pieces / nm ² is preferable, more preferably 1.5 to 3.8, based on the surface area of (B). Pieces / nm ² , and further preferably 2.0 to 3.5 pieces / nm ² .
The number of methyl groups can be measured from the relative ratio of the peak intensity of silanol groups and methyl groups on the silica surface by infrared spectroscopy. The surface area is determined by the BET method.

Further, the hydrophobicity index of silica (B) is not particularly limited, but is preferably 20 to 90, more preferably 25 to 85, and still more preferably, from the viewpoint of the hydrophobicity of (B) and the solidification property. Is 30 to 70, particularly preferably 40 to 70. The adjustment of the hydrophobicity index of (B) can be increased by increasing the number of alkyl groups covering the surface of (B), for example, when modifying the above-described alkyl group or the like, and can be decreased by reducing it.
Here, the hydrophobicity index is a numerical value obtained by the following method.
<Method of measuring hydrophobicity index>
Weigh 0.2 g of sample into a 200 ml beaker and add 50 ml of pure water.
While stirring magnetically, gradually add methanol below the liquid level until a sample is observed on the liquid level. The hydrophobicity index is calculated from the amount of methanol added until the sample is recognized on the liquid surface by the following formula.
Hydrophobicity index (%) = {x / (50 + x)} × 100
In the above formula, x represents the volume (ml) of added methanol.

  The form of silica (B) is preferably aggregated particles and / or agglomerated particles composed of spherical primary particles from the viewpoint of ease of handling. In addition, the number average particle diameter of the primary particles is preferably 7 to 40 nm, more preferably 8 to 35 nm, from the viewpoints of workability, solidification of the waste liquid, and adhesion of the surface of the water absorbent resin (A). More preferably, it is 9-30 nm. Measurement of the number average particle diameter of the primary particles can be performed with a laser scattering particle size distribution measuring apparatus.

The content (% by weight) of (B) in the solidifying agent of the present invention is such that the content of (B) is 0.05 to 2.00, based on the total weight of (A) and (B), Preferably it is 0.10-1.00, More preferably, it is 0.15-0.50. If it is less than 0.05%, the solidifying agent after being charged into the waste liquid has poor solidity at the lower layer of the waste liquid. On the other hand, when the content is more than 2.00%, the solidifying agent after being charged into the waste liquid has poor offset solidity in the upper layer portion of the waste liquid.
The content (% by weight) of (A) in the solidifying agent of the present invention is that the content of (A) is 98.00 to 99.95, based on the total weight of (A) and (B), Preferably it is 99.00-99.90, More preferably, it is 99.50-99.85. If it is more than 99.95%, the solidifying agent after being charged into the waste liquid has poor solidity in the lower layer of the waste liquid. On the other hand, if it is less than 98.00%, the solidifying agent after being charged into the waste liquid has poor solidity in the upper layer portion of the waste liquid.

  The weight average particle diameter of the water-absorbent resin (A) and the number average particle diameter of the primary particles of silica (B) are from the viewpoint of solidification, workability, and adhesion to the surface of (A) of (B) ( The weight average of A) is 106 to 750 μm, the number average particle diameter of the primary particle diameter of (B) is preferably 7 to 40 nm, and more preferably the weight average of (A) is 150 to 600 μm (B The number average particle diameter of the primary particle diameter is from 8 to 35 nm, particularly preferably the weight average of (A) is from 200 to 500 μm, and the number average particle diameter of the primary particle diameter of (B) is from 9 to 30 nm. That is.

The solidifying agent of the present invention can be easily obtained by mixing the water absorbent resin (A) and the silica (B). As a step of mixing the water absorbent resin (A) and the silica (B), from the viewpoint of ease of mixing, etc., among the steps of producing the water absorbent resin (A), the water absorbent resin (A ), Before the polymerization step, during the polymerization step, immediately after the polymerization step, during the crushing (mincing) step of the water-containing resin obtained by polymerization, immediately before the surface crosslinking step, during the surface crosslinking step, immediately after the surface crosslinking step, immediately before the drying step In the drying step or immediately after the drying step is preferable, more preferably immediately after the drying step. On the other hand, when the water-absorbent resin (A) is obtained by reverse phase suspension, the water-containing resin obtained by the polymerization and the organic resin used for the polymerization before the polymerization step, during the polymerization step, immediately after the polymerization step, during the dehydration step, immediately after the dehydration step. In the step of separating the solvent, immediately before the surface crosslinking step, during the surface crosslinking step, immediately after the surface crosslinking step, immediately before the drying step, during the drying step or immediately after the drying step, more preferably immediately after the drying step.
In any case, it is particularly preferable that the water-absorbent resin (A) is mixed in a state where the water content is 10% by weight or less, more preferably 8% by weight or less, and most preferably 5% by weight, from the viewpoint of solidification. It is to mix in the following states.
In addition, when moisture is heated by an infrared moisture measuring device (for example, JE400 manufactured by KETT Co., Ltd .: 120 ± 5 ° C., 30 minutes, ambient humidity before heating 50 ± 10% RH, lamp specification 100V, 40W) It is calculated | required from the weight loss of the water absorbing resin (A) before and behind heating.

Although it does not specifically limit as mixing temperature (degreeC), From a dispersible viewpoint, 10-130 are preferable, More preferably, it is 15-125, Most preferably, it is 20-120.
As an apparatus used for mixing the water absorbent resin (A) and the silica (B), an ordinary mixer may be used, for example, a cylindrical mixer, a screw mixer, a screw extruder, a turbine. Riser, Nauter type mixer, double-arm kneader, fluid mixer, V mixer, ribbon mixer, fluid mixer, airflow mixer, rotating disk mixer, conical blender, roll mixer, etc. Can be mentioned.

  In the solidifying agent of the present invention, it is preferable that the water-absorbent resin (A) is in the form of particles and the silica (B) is present on the particle surfaces of (A) from the viewpoint of solidification and the like.

The solidifying agent of the present invention includes any step as necessary {in the production step of the crosslinked polymer particles (A), a polymerization step, a crushing step, a drying step, a pulverizing step, a surface cross-linking step and / or before and after these steps. In addition, after the step of mixing the water absorbent resin (A) and the silica (B), etc.}, an additive can be added.
As additives, known additives (for example, Japanese Patent Application Laid-Open No. 2003-225565) {preservatives, fungicides, antibacterial agents, antioxidants, ultraviolet absorbers, colorants, fragrances, deodorants, and organic fibers Etc.}, etc., and one or more of these may be used in combination.

The water absorption (g / g) of the solidifying agent with respect to 25 ° C. physiological saline is preferably 7 to 90, more preferably 8 to 80, and still more preferably 10 from the viewpoint of water retention capacity and ease of production. ~ 70.
The amount of water absorption is measured by the following method.

[Measurement method of water absorption of solidifying agent]
A sample L (g) (about 1.0 g is weighed) of a solidifying agent is placed in a nylon net bag (250 mesh, 20 cm × 10 cm), and the bag is immersed in excess physiological saline. After 60 minutes of immersion, the whole bag is pulled up in the air, left to stand and drained for 30 minutes, and then the tea bag is taken out and the mass (Pg) is measured to the unit of 0.1 g. At the same time, a blank test is performed using a tea bag without a sample, and the mass (Qg) is measured.

Water absorption (g / g) = (PQ) / L

  In the present invention, the waste fluid containing body fluid is a waste fluid containing body fluid such as blood, lymph fluid, bone marrow fluid, amniotic fluid, sputum and saliva. It is discharged by surgery, anatomy in hospital, delivery at maternity hospital, inpatient fistula, etc., but part of living tissue excised at this time, physiological saline used for local cleaning, surgical instruments, operating table, etc. Contained substances such as washed water, disinfectant solution, treatment solution, used ampules, and trash.

  The amount of the solidifying agent of the present invention depends on the type of waste liquid containing body fluid, but the solidification time, the softness of the solidified product, and there is no risk of unabsorbed waste liquid or solidified product being scattered from the container, and From the viewpoint of the amount of unabsorbed solidifying agent (that is, economic efficiency), 10 to 100 g is preferable with respect to 1 L of waste liquid containing body fluid.

  The method of using the solidifying agent is not particularly limited, and the solidifying agent of the present invention is added to a suitable container containing a waste fluid containing body fluid and mixed as necessary. There is a method of putting the waste fluid containing body fluid into a suitable container containing, and mixing as necessary, but in order to prevent secondary infection due to scattering of the waste fluid, mixing with a stirring rod or shaking is preferable. Absent. The solidifying agent of the present invention is characterized by being easily solidified without being mixed. Further, the solidifying agent of the present invention may be used alone, or may be used by being wrapped in a water-soluble film, paper or the like.

  EXAMPLES Next, although an Example demonstrates this invention further, this invention is not limited to this. In addition, evaluation of the solidification time which is a test item of the solidification property test performed in the Example and the comparative example followed the following method.

<Measurement method of solidification time>
Two 224 ml narrow mouthed polybins {main body product name: PH-200, cap product name: 22.5 tongaric cap (made of an inner diameter of the opening 7 mm), made by Takemoto Container}, prepared by weighing 54 g of a solidifying agent, are prepared.
On the other hand, 1800 g of the following model blood is placed in a 2000 ml graduated cylinder (inner diameter: 95 mm) and the temperature is adjusted to 25 ° C. Next, open the lids of the two plastic bottles containing 54g of the solidifying agent in the graduated cylinder, and put both bottles upside down at a height of 10cm from the liquid level. The time from when the solidifying agent is added until the solution is solidified is measured.
Model blood: 4.0% by weight of glycerin, 0.5% by weight of sodium chloride, 0.4% by weight of sodium salt of carboxymethyl cellulose, 0.2% by weight of sodium bicarbonate, 50% by weight of physiological saline, 44. 9% by weight

<Example 1>
Water-absorbent resin (A1) {Product name: Aquapearl (registered trademark) E-200 (manufactured by Sundia Polymer Co., Ltd.), particle size adjusted product, crosslinked poly having an apparent density of 0.50 g / cm ³ and a weight average particle size of 385 μm 600 parts by weight of partial sodium salt of acrylic acid and silica (B1) (trade name: Aerosil R972 (manufactured by Nippon Aerosil Co., Ltd.), hydrophobic silica modified by covalently bonding a methyl group to the surface, and the methyl group covering the surface The number of particles is 2.7 particles / nm ^{2 based} on the surface of silica, the hydrophobicity index is 40, and the number average particle diameter of primary particles is 16 nm). Agent (1) was obtained. The above solidification time was measured for the obtained solidifying agent. The results are shown in Table 1.

<Example 2>
A solidifying agent (2) was obtained in the same manner as in Example 1 except that 2.1 parts by weight of silica (B1) in Example 1 was changed to 0.3 parts by weight. The obtained solidifying agent (2) was measured for solidification time in the same manner as in Example 1, and the results are shown in Table 1.

<Example 3>
A solidifying agent (3) was obtained in the same manner as in Example 1 except that 2.1 parts by weight of silica (B1) in Example 1 was changed to 12.2 parts by weight. The obtained solidifying agent (3) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Example 4>
In Example 1, silica (B1) is silica (B2) (trade name: Aerosil 200 (manufactured by Nippon Aerosil Co., Ltd.), hydrophilic silica having no methyl group covalently bonded to the surface, and has a hydrophobicity index of 0, primary. A solidifying agent (4) was obtained in the same manner as in Example 1 except that the number average particle diameter of the particles was changed to 12 nm. The obtained solidifying agent (4) was measured for solidification time in the same manner as in Example 1, and the results are shown in Table 1.

<Example 5>
In Example 1, silica (B1) is silica (B3) (hydrophobic silica modified by covalently bonding a methyl group to the surface, and the number of methyl groups covering the surface is 1.0 on the basis of the surface of the silica. / Nm ² , the hydrophobicity index was 30, and the number average particle size of the primary particles was changed to 16 nm). Thus, a solidifying agent (5) was obtained in the same manner as in Example 1. The obtained solidifying agent (5) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Example 6>
In Example 1, silica (B1) is silica (B4) (trade name: Aerosil R812S (manufactured by Nippon Aerosil Co., Ltd.), and the surface of the methyl group is covered with hydrophobic silica modified by covalently bonding a methyl group to the surface. The solidifying agent (as in Example 1 except that the number was changed to 3.9 particles / nm ^{2 based} on the surface of silica, the hydrophobicity index was 60, and the number average particle diameter of the primary particles was 7 nm). 6) was obtained. With respect to the obtained solidifying agent (6), the solidification time was measured in the same manner as in Example 1, and the results are shown in Table 1.

<Example 7>
In Example 1, the water-absorbent resin (A1) was changed to a water-absorbent resin (A2) (trade name: Aqua Pearl (registered trademark) DS50HP (manufactured by Sundia Polymer Co., Ltd.), a particle size adjusted product, an apparent density of 0.40 g / cm ³ , A solidifying agent (7) was obtained in the same manner as in Example 1 except that it was changed to a partially sodium salt of a crosslinked polyacrylic acid having a weight average particle diameter of 385 μm. The obtained solidifying agent (7) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Example 8>
In Example 1, the water-absorbent resin (A1) was changed to a water-absorbent resin (A3) (trade name: Sunfresh (registered trademark) ST-573 (manufactured by Sanyo Chemical Industries)), an apparent density of 0.60 g / cm ^3, to obtain a weight average particle size 385μm of crosslinked poly was changed to partial sodium salt) of acrylic acid in the same manner as in example 1 solidifying agent (8). The obtained solidifying agent (8) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Example 9>
In Example 1, the weight average particle diameter of the water absorbent resin (A1) particles was changed from 385 μm to 106 μm, and the number average particle diameter of the primary particles of silica (B1) was changed from 16 nm to 7 nm. In the same manner, a solidifying agent (9) was obtained. The obtained solidifying agent (9) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Example 10>
Example 1 is the same as Example 1 except that the weight average particle diameter of the water absorbent resin (A1) particles is changed from 385 μm to 750 μm, and the number average particle diameter of the primary particles of silica (B1) is changed from 16 nm to 40 nm. In the same manner, a solidifying agent (10) was obtained. The obtained solidifying agent (10) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Comparative Example 1>
A solidifying agent (11) was obtained in the same manner as in Example 1 except that 2.1 parts by weight of silica (B1) in Example 1 was changed to 12.9 parts by weight. With respect to the obtained solidifying agent (11), the solidification time was measured in the same manner as in Example 1, and the results are shown in Table 1.

<Comparative example 2>
A solidifying agent (12) was obtained in the same manner as in Example 1 except that 2.1 parts by weight of silica (B1) in Example 1 was changed to 0.2 parts by weight. The obtained solidifying agent (12) was measured for solidification time in the same manner as in Example 1, and the result is shown in Table 1.

<Comparative Example 3>
In Example 1, a solidifying agent (13) was obtained in the same manner as in Example 1 except that silica (B1) was not used. The obtained solidifying agent (13) was measured for solidification time in the same manner as in Example 1, and the results are shown in Table 1.

  The solidifying agent of the present invention can quickly and sufficiently solidify the waste liquid containing bodily fluids generated in hospitals and the like without being mixed with a stir bar or shaking the container by simply adding it. It is useful as a solidifying agent for waste liquid containing recovered body fluid.

Claims (7)

The water-absorbent resin (A) and silica (B) are contained, and the content of (A) is 98.00 to 99.95%, based on the total weight of (A) and (B), (B) The solidifying agent for solidifying the waste liquid containing a body fluid whose content is 0.05-2.00%. The solidifying agent according to claim 1, wherein the silica (B) is hydrophobic silica modified by covalently bonding a methyl group to the surface. Solidifying agent according to claim 1 or 2 carbon is 1.0 to 4.0 pieces / nm ² methyl groups covering the surface of the silica (B). The solidification agent according to any one of claims 1 to 3, wherein the hydrophobicity index of silica (B) is 20 to 90. The solidifying agent according to any one of claims 1 to 4, wherein the apparent density (g / cm ³ ) of the water absorbent resin (A) is 0.40 to 0.60. The solidifying agent according to any one of claims 1 to 5, wherein the water-absorbent resin (A) is in the form of particles and silica (B) is present on the particle surfaces of (A). The solidifying agent according to claim 6, wherein the water-absorbent resin (A) has a weight average particle diameter of 106 to 750 µm and a silica (B) primary particle has a number average particle diameter of 7 to 40 nm.