JP2519669B2 - Anti-clogging agent for liquid absorbent core - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a clogging preventive agent for a liquid absorbent core, more specifically a liquid absorbent sucked up by a liquid absorbent core for the purpose of deodorizing, aromatizing, sterilizing, etc., and heating it with a heating element. Liquid absorbent core used in a heating evaporation type device for heating and evaporating a chemical solution from the core
(Hereafter, the chemical liquid absorption core used in this heating evaporation type device
(Referred to as "chemical liquid absorbent core") .

[0002]

2. Description of the Related Art Conventionally, as a method of heating and evaporating such chemicals for the purpose of deodorizing, aromatizing, sterilizing, etc., a porous substrate such as fiberboard (solid A method of heating and evaporating a drug adsorbed on a mat is widely used. However, in this method, the amount of chemicals that can be impregnated in one solid mat is naturally limited, and it is essential to replace the mat and discard the used mat. Moreover, in addition to the serious drawback that the volatilization rate of the drug adsorbed on the mat decreases with time, the effective volatilization rate of the drug adsorbed on the mat is at most about 50%, and the drug remaining on the mat remains. The rate is as high as about 10%, and a stable drug volatilization effect cannot be maintained for a long time, which is still economically disadvantageous.

The problem of mat replacement and the defect that the effect disappears within a short period of time, which is found in the use of the solid mat, is solved,
As a heating evaporation method capable of maintaining the volatilization effect of a drug for a long period of time, a method in which the drug is heated and evaporated while being sucked up by a wicking core (liquid absorption core) in the form of a solution is considered. Various chemical vaporization devices using a wick have been proposed. In these devices, a solvent solution (chemical solution) of a drug is put in an appropriate container, and the solution is sucked up by using an absorbent core such as felt while being heated and evaporated from the upper part of the absorbent core.

However, in such a wicking type heating evaporation device, when it is actually used, the solvent constituting the liquid medicine is rapidly vaporized by heating the liquid absorption core, and the liquid medicine is gradually concentrated inside the core. Resinization, core material is smoked,
When carbonized, clogging causes clogging and makes it impossible to suck up and evaporate the drug solution continuously, a long-term sustained effect cannot be exhibited, and further, the drug volatilization effect cannot be avoided over time, and the drug is effective. The volatilization rate was low and the residual rate was high. As the cause of various harmful effects seen in the heating evaporation method using such a wick, not only the type of core and the type of solvent, but also the type of drug, concentration, a large number of heating conditions, etc. are considered. It was considered difficult to eliminate the above-mentioned adverse effects.

[0005]

The object of the present invention is to avoid (prevent) the clogging found in the liquid absorbent wick used in the wicking type heating and vaporization device described above, and to provide a long-lasting effect. Moreover, it is to provide a new anti-clogging agent capable of improving the total volatilization amount of the drug and the effective volatilization rate.

[0006]

According to the present invention,
5-di-t-butyl-4-hydroxytoluene, 3-t
-Butyl-4-hydroxyanisole, 3,5-di-t
-Butyl-4-hydroxyanisole, mercaptobenzimidazole, dilauryl-thio-di-propionate, 3-t-butyl-4-methoxyphenol, 2,6
-Di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, α-tocopherol, ascorbic acid, erythorbic acid, 2,2'-methylene -Bis-
(6-t-butyl-4-methylphenol), 2,2 '
-Methylene-bis- (6-t-butyl-4-ethylphenol), 4,4'-methylene-bis- (2,6-di-
t-butylphenol), 4,4'-butylidene-bis- (6-t-butyl-3-methylphenol), 4,
4'-thio-bis- (6-t-butyl-3-methylphenol), 1,1-bis- (4-hydroxyphenyl)
Cyclohexane, 1,3,5-trimethyl-2,4,6
-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, tetrakis [methylene (3,5-di-t) -Butyl-4-hydroxyhydrocinnamate)] methane, phenyl-β-naphthylamine, N, N'-diphenyl-p-phenylenediamine, 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 6-ethoxy. At least 1 selected from 2,2,2,4-trimethyl-1,2-dihydroquinoline
There is provided an agent for preventing clogging of a liquid absorbent core, which comprises various compounds.

The clogging preventive agent of the present invention is mixed with a chemical liquid composition for liquid absorbent core, and the composition is used in a wicking type heating evaporation device to induce clogging of the liquid absorbent core. Without increasing the life of the core, and based on this, it is possible to significantly improve the transpiration property of the drug (volatilization amount and effective volatilization rate),
It is possible to continuously exhibit an excellent chemical vaporization effect over a long period of about 200 hours or more.

As the drug in the present invention, any of various drugs conventionally used for deodorizing, perfuming, sterilizing, repelling, antifungal, controlling plant growth, weeding, acaricide, etc. can be used. Specific examples thereof include the following.

Deodorant lauryl methacrylate, geranyl crotonate, acetophenone myristate, paramethylacetophenone benzaldehyde, benzyl acetate, benzyl propionate, amylcinnamic aldehyde, anisic aldehyde, diphenyl oxide, methyl benzoate, ethyl benzoate, Methyl phenylacetate, ethyl phenylacetate,
Neoline, Safrole, Sedawood oil, Cedar vegetable oil, Citronella oil, Labanten oil, Petigrain oil, Lemongrass oil, etc.

・ Fragrances As natural fragrances, animal fragrances such as musk, spirit cat scent, ryunobu scent; Avies oil, ajokun oil, almond oil, angelica root oil, page oil, bergamot oil, perch oil, boa rose oil , Kayabuti oil, gananga oil, capsicum, caraway oil, cardamom oil, cassia oil, celery oil, cinnamon oil, citronella oil, cognac oil,
Coriander oil, Kyupepu oil, cumin oil, camphor oil, Jill oil, Esutogoran oil, eucalyptus oil, fennel oil, garlic oil, ginger oil, grapefruit oil, hop oil, juniper base Lee oil, laurel leaf oil, lemon oil, lemon grass Oil, ropage oil, mace oil, nutmeg oil, mandarin oil, tangerine oil, mustard oil, mackerel oil, orange flower oil, onion oil, pepper oil, orange oil, sage oil, star anise oil, turpentine oil, wormwood oil , And botanical flavors such as vanilla bean extract.

[0011] Artificial flavoring is a synthetic or extracted perfumes, pinene, hydrocarbons such as limonene; linalool, geraniol, shea Toroneroru, menthol, Bo Runeoru, alcohols such as benzyl alcohol, anise alcohol, beta-phenylethyl alcohol; Ane DOO Lumpur, phenols such as eugenol; n-butyraldehyde, isobutyraldehyde, hexyl aldehyde, heptyl aldehyde, citral, citronellal, benzaldehyde, cinnamic aldehyde, Heriotorobin, aldehydes such as Wanirin; methyl amyl ketone, methyl nonyl ketone , Ketones such as diacetyl, acetylpropionyl, acetylbutyryl, carvone, menthone, camphor, acetophenone, p-methylacetophenone, and ionone; amylbutyllac Lactones or oxides such as ethyl methyl phenylglycidate, γ-nonyl lactone, coumarin and cineol; methyl formate, isopropyl formate, linaliherformate, ethyl acetate, octyl acetate, menthyl acetate, benzyl acetate, cinna mill acetate, butyl propionate, isoamyl acetate, isobutyrate isopropyl, isovalerate Guraniru, allyl caproate, butyl heptyl acid, mosquito-flop acrylic acid octyl, f leptin carboxylate, ethyl pelargonate, octene Chin carboxylic acid methylcarbamoyl <br / >, Isoamyl caprate, methyl laurate, ethyl myristate, ethyl benzoate, benzyl benzoate, methyl phenylacetate, butyl phenylacetate, methyl cinnamate, cinnamyl cinnamate, methyl salicylate Including ethyl anisate, methyl anthranilate, ethyl pyruvate, ethyl α butyrate esters such like.

The fragrance may be only one kind, or may be a mixed fragrance prepared by mixing two or more kinds.

Along with the fragrance, a volatilization retention agent such as patchouli oil, a modulator such as eugenol, and other various components used in the fragrance industry may be added.

Industrial bactericide 2,4,4'-trichloro-2'-hydroxydiphenyl ether (Irgassan DP300, manufactured by Ciba-Geigy), 2,3,5,6-tetrachloro-4 (methylsulfonyl) pyridine ( Dausil S-13, Dow Chemical Company), alkylbenzyl dimethyl ammonium
Chloride (benzalkonium chloride, manufactured by Nikko Chemicals Co., Ltd.), benzyl dimethyl {2- [2- (p-1,
1,3,3-Tetramethylbutylphenoxy) ethoxy] ethyl} ammonium chloride (benzethonium chloride, manufactured by Sankyo Co., Ltd.), 4-isopropyltropolone (hinokitiol, manufactured by Takasago International Corporation), N,
N- dimethyl -N- phenyl--N '- (fluorodichloromethylthio) sulfonamide (Prevention Doll A _4, manufactured by Bayer), 2- (4'-thiazolyl) benzimidazole (TBZ, Hokko Chemical Co., Ltd.), N-
(Fluorodichloromethylthio) -phthalimide (Preventol A ₃ , manufactured by Bayer), 6-acetoxy-
2,4-dimethyl-m-dioxin (Dioxin, manufactured by Givaudan) and the like.

Agricultural bactericides: ethylene bis (dithiocarbamate) zinc (Dineb, manufactured by Rohm and Haas), ethylene bis (dithiocarbamic acid) manganese (Manneb, manufactured by Rohm and Haas), zinc, manneb complex mixture ( Manzeb, manufactured by Rohm and Haas), bis (dimethyldithiocarbamic acid)
Ethylene bis (dithiocarbamate) dizinc (polycarbamate, Tokyo Organic Chemical Co., Ltd.), bis (dimethylthiocarbamoyl) disulfide (Thiram, Rohm and Haas Co.), crotonic acid 2,6-dinitro-4-octylphenyl reaction Isomeric mixture (DPC, manufactured by Rohm and Haas), N-trichloromethylthiotetrahydrophthalimide (captan, manufactured by Sankyo Co.), 2,3-dicyano-1,4-dithiaanthraquinone (dithianon, manufactured by Merck), 2, 4-dichloro-6- (o-chloroanilino) -S-triazine (triazine, manufactured by Fuji Kasei),
S-n-butyl S'-p-tert-butylbenzyl N-3-pyridyldithiocarboxylic imidate (Denmart, Sumitomo Chemical Co., Ltd.), N- (3 ', 5'-dichlorophenyl) -1,2-dimethylchloropropane Dicarboximide (Sumilex), bis (chlorophenyl)
Trichloroethanol (kensen), 6-methylquinoxaline-2,3-dithiocarbonate (morestan),
Tetrachloroisophthalonitrile (Danicol), methyl-1- (butylcarbamoyl) -2-benzimidazole carbamate, blasticidin S-benzylaminobenzenesulfonate, streptomycin hydrochloride,
Kasugamycin hydrochloric acid feast, cycloheximide, etc.

Pest repellents dimethyl phthalate, 2,3,4,5-bis- (Δ _2-
Butylene) tetrahydrofuran, 2,3,4,5-bis- (Δ ₂ -butylene) tetrahydrofurfuryl alcohol, N, N-diethyl-m-toluamide DET), caprylic acid diethylamide, 2,3,4,5 -Bis- (Δ
₂ -butylene) tetrahydrofurfural, di-m-propyl-isocinchomeronate, secondary butylstyrylketone, nonylstyrylketone, N-propylacetanilide, 2-ethyl-1,3-hexanediol, di-
n-butyl succinate, 2-butoxyethyl-2-furfridene acetate, dibutyl phthalate, tetrahydrothiophene, β-naphthol, diallyl disulfide, bis (dimethylthiocarbamoyl) disulfide and the like.

Rodent repellents Tetramethylthiuram disulfide, guanidine, naphthalene cresol, cycloheximide, zinc dimethyldithiocarbamate, cyclohexylamine, N,
N-dimethylsulfenyldithiocarbamate and the like.

Dog cat repellent 2,6-dimethyl-octadiene- (2,6) -al
(8) citral), O, O-diethyl S-2-ethylthioethyldithiophosphate (ETP), O, O
-Diethyl S-2-isopropylthioethyldithiophosphate ( MIP) and the like.

[0019] - bird repellents γ- Kuroraroze, 4- (methylthio) -3,5-xylyl -N- methylcarbamate, 4-amino-Pi lysine anthraquinone, tetramethyl thiuram disulfide,
Diallyl disulfide and the like.

・ Rodent control agent Antu, monofluor sodium acetate, warfarin,
Cumacrole, fumarine, bear tetralyl silyloside,
Norbomide, N-3-pyridylmethyl-N'-nitrophenylurea, endroside, alphanaphthylthiourea, thiosemicarbazide, difenacum, pival, chlorofacinone, silatrene, calciferol and the like.

-Anticides such as permethrin and chlordane.

Antifungal agent α-bromo-cinnamic aldehyde, N, N-dimethyl-N-phenyl-N '-(fluorodichloromethylthio) -sulfamide and the like.

Plant growth regulators 4-chlorophenoxyacetic acid, gibberellin, N- (dimethylamino) succinamide, α-naphthylacetamide and the like.

Herbicides such as 2,4-D soda salt and 3,4-dichloropropionanilide.

Acaricide: benzyl benzoate, resmethrin, quersen, etc.

The above drug is prepared in the form of a solution. As a solvent for preparing the drug solution, various organic solvents (including water) that are usually used, typically, a hydrocarbon solvent can be used. Especially the boiling point range is 150 ~
Aliphatic hydrocarbons (paraffinic hydrocarbons and unsaturated aliphatic hydrocarbons) at 350 ° C. are preferable, and n-paraffins having the above boiling point range include those having 10 to 18 carbon atoms [Dictionary of Organic Compounds, 5th ed., 198
2). Among them, n-paraffin, isoparaffin, etc. are particularly preferable because they are practically nontoxic, have no odor, and have extremely low risk of fire. Examples of the organic solvent other than the hydrocarbon-based solvent include glycols such as glycerin, propylene glycol and hexylene glycol, alcohols such as methanol, isopropanol, 1-octanol and 1-dodecanol, ketones such as acetone and acetophenone, and dihexyl. Examples include ethers, ethers such as diethylene glycol diethyl ether, dioctyl adipate, diethyl malonate, diethyl phthalate, etc., benzene, xylene, chlorsene, solvent naphtha, sorbene, benzicol, chloroform, methylnaphthalene, aromatic naphtha, etc. it can.

The solvent solution of the above-mentioned drug is appropriately determined depending on the kind of drug to be used and is not particularly limited, but usually the drug concentration is about 1 to 20% by weight, preferably 2 to
It is better to prepare it so as to be 10% by weight.

The chemical solution (chemical composition for liquid-absorbent core) used in the present invention must contain at least one selected from the following compound group in an organic solvent solution of the above chemical agent.

3,5-di-t-butyl-4-hydroxytoluene (hereinafter referred to as CA) 3-t-butyl-4-hydroxyanisole (hereinafter referred to as CB)
3,5-di-t-butyl-4-hydroxyanisole (hereinafter referred to as CC) Mercaptobenzimidazole (hereinafter referred to as CD) Dilauryl-thio-di-propionate (hereinafter referred to as CE) 2,2′-methylene- Bis- (6-t-butyl-4-methylphenol) (hereinafter referred to as CF) 2,2'-methylene-bis- (6-t-butyl-4-ethylphenol) (hereinafter referred to as CG) 4,4'- Methylene-bis- (2,6-di-t-butylphenol) (hereinafter referred to as CH) 4,4′-butylidene-bis- (6-t-butyl-3-)
Methylphenol (hereinafter referred to as CI) 4,4′-thio-bis- (6-t-butyl-3-methylphenol) (hereinafter referred to as CJ) 1,1-bis- (4-hydroxyphenyl) cyclohexane (hereinafter referred to as CK) 1,3,5-trimethyl-2,4,6-tris (3,5
-Di-t-butyl-4-hydroxybenzyl) benzene (hereinafter referred to as CL) tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane (hereinafter referred to as CM) tetrakis [methylene (3,5-di -T-butyl-4-
Hydroxyhydrocinnamate)] methane (hereinafter referred to as CN) phenyl-β-naphthylamine (hereinafter referred to as CP) N, N'-diphenyl-p-phenylenediamine (hereinafter referred to as CQ) 2,2,4-trimethyl-1,2- Dihydroquinoline polymer (hereinafter referred to as CR) 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline (hereinafter referred to as CS) 3-t-butyl-4-methoxyphenol (hereinafter referred to as CU) 2,6- Di-t-butyl-4-ethylphenol (hereinafter referred to as CV) stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (hereinafter referred to as CW) α-tocopherol (hereinafter referred to as CX) ascorbin Acid (hereinafter referred to as CY) and erythorbic acid (hereinafter referred to as CZ).

The compounds CA to CZ may be used alone or in combination of two or more.
The amount used is not particularly limited as long as the intended effect of preventing clogging of the absorbent core according to the present invention can be obtained by blending them, but it is about 0 in the normally obtained liquid composition for absorbent core. ．
It is preferable that the content is 05 to 2.0% by weight, preferably about 0.1 to 1.0% by weight, which has the effect of preventing clogging of the absorbent core over a long period of time. A long-lasting chemical vaporization effect is achieved.

The chemical solution containing the anti-clogging agent of the present invention is
It is applied to a wicking type heating and vaporizing apparatus using various conventionally known liquid-wicking cores, and thus can exhibit the above-mentioned desired excellent effects. As the above-mentioned device, for example, Japanese Patent Publication No. 52-12106.
JP-A-58-45670 and JP-A-58-45670 can be exemplified, and one specific example thereof is shown in the accompanying drawings.

FIG. 1 is a schematic view of a wicking type heating evaporation device suitable for applying a chemical solution containing the anti-clogging agent of the present invention. The apparatus is a core for supporting a liquid absorption core (1). A drug solution container (3) having a support (2), a liquid absorbent core (1) inserted into the container by projecting its upper part, and a hollow disk for indirectly heating the upper side surface part thereof. Heating element (4), support part (5) for supporting the heating element (4)
And a heating element support base (7) having support legs (6). The heating element (4) has a cord (not shown) for energizing it to generate heat.

The liquid absorbent core (1) used in the above apparatus may be any of various commonly used materials such as felt, cotton, pulp, non-woven fabric, asbestos, and inorganic moldings. Cores, pulp cores and molded inorganic cores are preferred. Specific examples of the inorganic molding core include porcelain porous material, glass fiber, inorganic fiber such as asbestos hardened with a binder such as gypsum or bentonite, kaolin, activated clay, talc, diatomaceous earth, clay, perlite, bentonite. , Gypsum, alumina, silica, alumina silica, titanium, vitreous volcanic rock firing powder, vitreous volcanic ash firing powder, etc. alone or with wood powder, charcoal powder,
Examples thereof include activated carbon and the like, which are hardened with a sizing agent such as dextrin, starch, gum arabic, and synthetic glue CMC. A particularly preferred liquid absorbent core is 100 parts by weight of the above-mentioned mineral powder and 10 to 300 parts by weight of wood powder or a mixture of the wood powder up to an equal weight of carbon powder and / or activated carbon. It is produced by blending the ingredients in an amount of 5 to 25% by weight, further adding water to the ingredients, kneading, extruding, and drying. The liquid-wicking core has an oil-absorption rate (a chemical solution arrival time) of 1
It is desirable that the time is -40 hours, preferably 8-21 hours.

The oil absorption rate is the time required for n-paraffin to reach the core apex by immersing a liquid absorbing core having a diameter of 7 mm and a length of 70 mm up to 15 mm in the n-paraffin liquid having a liquid temperature of 25 ° C. Means the value determined by measuring

In the absorbent core, the mineral powder,
In addition to wood flour and sizing agent, if necessary, pigments such as macalite green, sorbic acid and its salts, and antifungal agents such as dehydroacetic acid can be added.

As the heating element used in the above apparatus, a heating element which normally generates heat when energized is generally used, but the heating element is not limited to this, and for example, an air oxidation heating material, a platinum catalyst, a honeycomb metal catalyst ( It may be any known heating element such as a heating material utilizing a material which generates heat upon contact with alcohol).

The method of evaporating the chemical solution in the above-mentioned apparatus using the chemical solution containing the anti-clogging agent of the present invention may be the same as the use of the conventional apparatus of this kind, for example, the chemical solution may be evaporated from the absorbent core. It can be carried out by heating the liquid absorbent core to an appropriate temperature. The heating temperature is appropriately determined according to the type of drug and the like. However, as for this heating temperature, the surface temperature of the heating element is 40
It is necessary to satisfy the condition that the temperature is in the range of to 150 ° C, preferably 85 to 145 ° C, and the surface temperature of the absorbent core is 30 to 135 ° C, preferably 70 to 130 ° C.

Thus, according to the present invention, it is possible to surely avoid clogging of the absorbent core and to volatilize the drug continuously for a long period of time with a drug concentration capable of producing a sufficient effect.

[0039]

EXAMPLES Examples will be given below to explain the present invention in more detail.

[0040]

Examples 1 to 66 The chemicals, organic solvents and compounds CA to CZ shown in Table 1 below were added and blended in predetermined proportions to obtain chemical liquid compositions (Examples No. 1 to 65). .

[0041]

Comparative Examples 1 to 7 Comparative chemical liquid compositions (Comparative Examples No. 1 to 7) were obtained in the same manner as in Examples 1 to 65 except that the compounds CA to CZ were not added and compounded.

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

[Table 3]

[0045]

[Table 4]

The symbols in the section of solvent in Table 1 are as follows.

The symbols in the section of solvent in Table 1 are as follows. BA ... Boiling point 150-180 ° C / 760 mmHg aliphatic hydrocarbon BB ... Boiling point 180-210 ° C / 760 mmHg aliphatic hydrocarbon BC ... Boiling point 210-240 ° C / 760 mmHg aliphatic hydrocarbon BD ... Boiling point 240-270 ° C / aliphatic hydrocarbons BE ... boiling 270 to 300 ° C. / 760 mmHg aliphatic hydrocarbon BF ... boiling 300 to 350 ° C. / 760 mmHg aliphatic hydrocarbon BG ... Pro Pi glycol of 760 mmHg + water (50/50) mixture

As the absorbent core, 60 parts by weight of pearlite and 20 parts by weight of wood flour were mixed with 20 parts by weight of starch and water, and the mixture was kneaded and dried by extrusion molding (diameter 7 mm × length 70 m).
m, oil absorption speed of about 14 hours), and as the heating element (4), a hollow disk-shaped heating element having an inner diameter of 10 mm and a thickness of 10 mm was used.

The volatile amount of the drug was obtained by collecting the volatile vapor by suction on a silica gel column every hour, extracting this silica gel with chloroform, concentrating it, and quantitatively analyzing it with a gas chromatograph.

10 hours after the heating of the chemical liquid sample is started, 10
The results of determining the amount of drug volatilization (mg / hr) per hour after 0 hour, 200 hours, 300 hours and 400 hours are shown in Table 2 below.

[0051]

[Table 5]

[0052]

[Table 6]

[0053]

[Table 7]

From Table 2 above, according to the present invention, the volatilization amount of the drug can be remarkably improved, and the improved volatilization amount can be continuously expressed even after 400 hours from the start of heating with almost no decrease. It is clear to get.

[Brief description of drawings]

FIG. 1 is a schematic view of an example of an apparatus suitable for applying a chemical composition for absorbent cores containing the anti-clogging agent of the present invention.

[Explanation of symbols]

(1) ... Liquid absorbing core, (2) ... Core support, (3) ... Chemical liquid storage container, (4) ... Heating element

Claims (1)

(57) [Claims] 1. 3,5-Di-t-butyl-4-hydroxytoluene, 3-t-butyl-4-hydroxyanisole, 3,5-di-t-butyl-4-hydroxyanisole, mercaptobenzimidazole. Sol, dilauryl-thio-di-propionate, 3-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl) −
4-hydroxyphenyl) propionate, α-tocopherol, ascorbic acid, erythorbic acid, 2,2 ′
-Methylene-bis- (6-t-butyl-4-methylphenol), 2,2'-methylene-bis- (6-t-butyl-4-ethylphenol), 4,4'-methylene-bis- ( 2,6-di-t-butylphenol), 4,4 '
-Butylidene-bis- (6-t-butyl-3-methylphenol), 4,4'-thio-bis- (6-t-butyl-3-methylphenol), 1,1-bis- (4-hydroxy) Phenyl) cyclohexane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-
4-hydroxybenzyl) benzene, tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, tetrakis [methylene (3,5-di-t-butyl-
4-Hydroxyhydrocinnamate)] methane, phenyl-β-naphthylamine, N, N′-diphenyl-p-
Phenylenediamine, 2,2,4-trimethyl-1,2
-Dihydroquinoline polymer and 6-ethoxy-2,
A clogging preventive agent for a liquid absorbent liquid core, comprising at least one compound selected from 2,4-trimethyl-1,2-dihydroquinoline.