JP7140364B2 - lice egg repellent - Google Patents

Description

TECHNICAL FIELD The present invention relates to a louse egg repellent that inhibits the hatching of lice from their eggs.

BACKGROUND ART Conventionally, sanitary pest control agents that are applied to humans and animals for use in order to prevent damage from lice and prevent the spread of damage are known. In general, even compositions that are said to be effective against lice are often ineffective against lice eggs. This is because louse eggs consist of hard shells and are completely different from the body structure of lice.

For example, Patent Document 1 discloses a pediculicide containing at least one of a higher alcohol having 9 to 24 carbon atoms and a fatty acid having 1 to 22 carbon atoms.

Further, in Patent Document 2, benzoic acid is added so as to exhibit an ovicidal effect on the eggs of crawling pests such as fleas, lice, mites, ants, cockroaches, and spiders, and the eggs of flying pests such as mosquitoes, flies, and moths. Pest ovicides containing desodium or octaacetylated sucrose and nonionic surfactants are disclosed.

JP 2012-31169 A JP 2017-206455 A

However, even if the pediculocidal agent described in Patent Document 1 has an exterminating effect on lice, there is a problem that the louse eggs do not have an exterminating effect and the lice hatch.

Regarding the ovicide for insect pests described in Patent Document 2, although louse eggs are also mentioned in the specification, the effect of inhibiting hatching of Culex pipiens, ant, and cockroach eggs in Examples is only disclosed, and it is not clear whether it has an exterminating effect on lice eggs.

Therefore, it is an object of the present invention to provide an agent for repelling nits that can inhibit hatching of lice eggs, which are more difficult to eradicate than lice.

[1] That is, the present invention comprises 0.1 to 40% by weight of a fatty acid ester, which is isopropyl palmitate or isopropyl myristate , and 0.1 to 40% by weight of a siloxane having a linear skeleton and being oily at room temperature of 25°C. 0.1-40% by weight of a nonionic surfactant, 0.1-30% by weight of a C12-18 fatty acid, and 0.1-30% by weight of a C12-18 alcohol . 1 to 30% by weight and 21 to 43.1% by weight of liquid paraffin .

According to the agent for repelling nits of the present invention, it is possible to inhibit hatching of lice eggs, which are more difficult to exterminate than lice.

Hereinafter, embodiments of the agent for repelling nits of the present invention will be described in detail. In addition, when there is a notation indicating a range in the description, it includes the upper limit and the lower limit.

The fatty acid ester used in the present invention is a compound obtained by dehydration condensation of an alcohol and a fatty acid, more specifically, a compound obtained by dehydration condensation of a monohydric alcohol and a fatty acid having 12 to 18 carbon atoms. be. Although the mechanism of action is not clear, the use of fatty acid esters can significantly suppress the hatching of lice from lice eggs.

Specific examples of fatty acid esters include methyl palmitate, ethyl palmitate, isopropyl palmitate, ethylhexyl palmitate, methyl myristate, ethyl myristate, isopropyl myristate, ethylhexyl myristate, methyl isostearate, ethyl isostearate, and isostearin. Compounds obtained by dehydration condensation of straight or branched monohydric alcohols having 1 to 8 carbon atoms such as isopropyl acid and ethylhexyl isostearate and fatty acids having 12 to 18 carbon atoms and having straight or branched chains is preferred. Moreover, the said fatty acid ester can be used only 1 type or in combination of 2 or more types.

Further, in the louse egg repellent of the present invention, the content of the fatty acid ester is preferably 0.1 to 40% by weight, more preferably 1 to 30% by weight, and most preferably 2 to 20% by weight. If the content of the fatty acid ester is within this range, hatching of lice from lice eggs can be remarkably suppressed.

The siloxane used in the present invention is a compound having a skeleton of silicon and oxygen and having a siloxane bond (Si--O--Si bond). For example, it is an organic compound obtained by hydrolyzing and dehydrating condensation of an organoalkoxysilane. Although the mechanism of action is not clear, the use of siloxane can significantly inhibit hatching of lice from lice eggs.

Specifically, siloxanes include linear siloxanes such as methylpolysiloxane, ethylpolysiloxane, and methylphenylpolysiloxane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dimethicone, Cyclic siloxanes such as vinyl dimethicone are preferred. It is ^more preferable that the siloxane has a linear skeleton and is oily at room temperature of 25.degree. Moreover, the said siloxane can be used only 1 type or in combination of 2 or more types.

In addition, the content of siloxane in the louse egg repellent of the present invention is preferably 0.1 to 40% by weight, more preferably 1 to 30% by weight, and most preferably 2 to 20% by weight. When the siloxane content is within this range, hatching of lice from lice eggs can be remarkably suppressed.

In the present invention, a surfactant can be blended. Examples of surfactants include cationic surfactants, anionic surfactants, amphoteric surfactants, and nonionic surfactants. When preparing the lice egg repellent of the present invention, a water-soluble component In order to prevent the separation of each component when blending, to disperse the fatty acid ester and siloxane, and furthermore, to give the lice egg repellent of the present invention foaming or defoaming properties. be.

Specifically, surfactants include anionic surfactants such as alkylbenzenesulfonates, alkylpolyoxyethylene sulfates, alkylsulfates, alkylphosphates and fatty acid salts, and alkyltrimethylammonium salts and dialkyldimethyl Cationic surfactants such as ammonium salts, alkylbenzyldimethylammonium salts, fatty acid alkanolamides, polyoxyethylene alkylamines, alkyl alkanolamides, alkylamine oxides, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, fatty acids Nonionic surfactants such as sorbitan esters, fatty acid glycerol esters, fatty acid polyglycerol esters, fatty acid polyoxyethylene sorbitan esters, fatty acid polyoxyethylene glycerol esters, and fatty acid polyoxyethylene polyglycerol esters, and imidazolines having alkyl groups , carbobetaine-based, amino acid-based, and amine oxide-based amphoteric surfactants are preferred. Further, the above surfactants can be used alone or in combination of two or more.

Also, among the above types of surfactants, it is preferred that nonionic surfactants are included. Among them, at least one selected from ester type, ether type, and ester ether type is more preferable, and not only liquid or solid 100% pure compounds, but also aqueous solutions obtained by diluting them with a predetermined amount of water. good.

Examples of ester-type nonionic surfactants include carboxylic acids and polyhydric alcohols having main chains of hydrocarbon groups and acyl groups having straight or branched chains of 1 to 22 carbon atoms, aromatic groups, and combinations thereof. It is preferably a compound obtained from Further, the hydrocarbon group may be straight chain or branched chain, saturated or unsaturated, having 1 to 18 carbon atoms. Specifically, sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan distearate, glycerin monolaurate, glycerin monopalmitate, glycerin monostearate, glycerin distearate, etc. of glycerin fatty acid ester and the like can be used.

Examples of ether-type nonionic surfactants include monohydric alcohols and polyvalent A compound obtained from a functional alcohol is preferred. Further, the hydrocarbon group may be straight chain or branched chain, saturated or unsaturated, having 1 to 18 carbon atoms. Specifically, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene myristyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene polyoxypropylene glycol, etc. polyoxyethylene alkyl ethers, polyoxyethylene alkylamines, etc. can be used.

Examples of ester ether type nonionic surfactants include carboxylic acids and polyalkylenes having main chains of hydrocarbon groups and acyl groups having straight or branched chains of 1 to 22 carbon atoms, aromatic groups, and combinations thereof. Compounds obtained from polyhydric alcohols to which oxides or polyalkylene oxides are added are preferred. Further, the hydrocarbon group may be straight chain or branched chain, saturated or unsaturated, having 1 to 18 carbon atoms. Specifically, polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyethylene glycol monolaurate, Polyoxyethylene fatty acid esters such as polyethylene glycol monostearate, polyoxyethylene glycerin fatty acid esters such as polyoxyethylene glycerin monolaurate, polyoxyethylene glycerin monopalmitate, and polyoxyethylene glycerin monooleate can be used. can.

Further, in the louse egg repellent of the present invention, the content of the surfactant is preferably 0.1 to 40% by weight, preferably 1 to 30, by adjusting the balance with the type and amount of other ingredients. % by weight is more preferred, and 2-20% by weight is most preferred. If the content of the surfactant is within this range, separation of each component can be prevented when blending the water-soluble component, and the fatty acid ester and siloxane can be dispersed. Certain lice ovumicides can have foaming or defoaming properties.

In the present invention, fatty acids can be blended. More specifically, the fatty acid is a monovalent carboxylic acid represented by the general formula CnHmCOOH, n is an integer of 0 or more and m is an integer of 1 or more, has a linear or branched structure, and is saturated or It is a compound having an unsaturated structure. By using fatty acids, the effect of suppressing hatching of lice from lice eggs can be exhibited.

Specifically, fatty acids include formic acid, acetic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, Margaric acid, stearic acid, isostearic acid, oleic acid, vaccenic acid, linoleic acid, linolenic acid, araginic acid, eicosenoic acid, eicosapentaenoic acid, behenic acid, docosahexaenoic acid, lignoceric acid, cerotic acid, montanic acid, melissic acid, etc. Also included are coconut oil fatty acids and beef tallow fatty acids obtained from natural fats and oils. Fatty acids having 1 to 22 carbon atoms are preferably used because they are commonly used and readily available. More preferably, fatty acids with 8 to 20 carbon atoms are used because they are inexpensive and readily available. In addition, the above fatty acids can be used alone or in combination of two or more.

Further, in the louse egg repellent of the present invention, the content of fatty acid is preferably 0.1 to 30% by weight, preferably 1 to 20% by weight, by adjusting the balance with the type and amount of other ingredients. is more preferred, and 2 to 10% by weight is most preferred. When the fatty acid content is within this range, the effect of suppressing hatching of lice from lice eggs can be exhibited.

Higher alcohols can be blended in the present invention. More specifically, higher alcohols are aliphatic primary alcohols having 6 to 22 carbon atoms and are compounds having a linear or branched structure. By using a higher alcohol, the effect of suppressing hatching of lice from lice eggs can be exhibited.

Examples include 1-hexanol, capryl alcohol, 2-ethylhexanol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, linolyl alcohol and behenyl alcohol. Higher alcohols having 9 to 24 carbon atoms are preferably used because they are commonly used and readily available. Higher alcohols having 10 to 22 carbon atoms are more preferably used because they are inexpensive and readily available. Further, the above higher alcohols can be used alone or in combination of two or more.

Further, in the louse egg repellent of the present invention, the content of higher alcohol is preferably 0.1 to 30% by weight, preferably 1 to 20% by weight, by adjusting the balance with the type and amount of other ingredients. % is more preferred, and 2-10% by weight is most preferred. If the content of the higher alcohol is within this range, the effect of suppressing hatching of lice from lice eggs can be exhibited.

In the present invention, a hydrocarbon compound can be blended. More specifically, the hydrocarbon compound is a saturated aliphatic hydrocarbon that is liquid at 25°C. By using a hydrocarbon compound, when the agent for repelling nits of the present invention is applied to the user's skin or hair, it can be easily spread and easily penetrated.

Further, in the present invention, a lower alcohol having 1 to 4 carbon atoms or water can be blended as a water-soluble compound. For example, lower alcohols that can be used include ethanol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol and tert-butyl alcohol. In addition, the said alcohol can be used only 1 type or in combination of 2 or more types.

Furthermore, in order to prevent corrosion such as deterioration due to oxidation of the formulation, vitamin C (ascorbic acid), vitamin E (α-tocopherol), BHT (dibutylhydroxytoluene), BHA (butylhydroxyanisole), sorbic acid, potassium sorbate, Antioxidants such as sodium sulfite can be added. Moreover, paraoxybenzoic acid ester can also be added for the purpose of antiseptic. Dipotassium glycyrrhizinate can also be added for the purpose of anti-inflammatory action. A phosphate buffer or the like can also be added for the purpose of adjusting the pH of the formulation.

A thickening agent can be added to prevent dripping of the liquid when it adheres to the louse eggs and to keep the active ingredient in the louse eggs for a long time. Specifically, carboxymethylcellulose, xanthan gum, guar gum, carboxyvinyl polymer and the like can be used as thickeners.

In the present invention, insecticides may not be used, but their use is not prohibited, and various insecticides such as pyrethroids, neonicotinoids, and macrolides can be blended. Specifically, preferred pyrethroids include permethrin, phenothrin, and nephrothurant extract; preferred neonicotinoids include imidacloprid and dinotefuran; and preferred macrolides include ivermectin and emamectin.

Furthermore, 1-menthol can be added to give a refreshing feeling, and various perfumes can be added to give a fragrance.

Examples of the present invention will be specifically described below. In addition, the present invention is not limited to the following examples.

<Example 1>
In a Griffin beaker with a capacity of 200 ml, 7 g of isopropyl palmitate (trade name “Exepar IPP”, manufactured by Kao Corporation) as a fatty acid ester, and methylpolysiloxane (trade name “KF-96A-10CS”, Shin-Etsu Chemical Co., Ltd.) as siloxane. made) 3.5 g,
19.4 g of polyoxyethylene glycol monolaurate (12E.O.) as a surfactant, 5.3 g of isostearic acid as a fatty acid, 3.1 g of myristyl alcohol as a higher alcohol, 43.1 g of liquid paraffin as a hydrocarbon compound, water-soluble As a compound, 5.3 g of ethanol and 3 g of purified water were mixed to prepare 89.7 g (100 ml) of preparation. Then, the mixture was stirred and mixed while being indirectly heated in a water bath at 40° C. until the mixture became uniform, and then allowed to cool to obtain a composition.

<Example 2>
A composition was obtained in the same manner as in Example 1, except that 22.1 g of liquid paraffin and 24 g of purified water were used.

<Example 3>
A composition was obtained in the same manner as in Example 1, except that 21 g of liquid paraffin and 25.1 g of purified water were used.

<Example 4>
A composition was obtained in the same manner as in Example 1, except that 7 g of isopropyl myristate (trade name “Exepar IPM”, manufactured by Kao Corporation) was used instead of isopropyl palmitate as the fatty acid ester.

<Comparative Example 1>
A composition was obtained in the same manner as in Example 1 except that 6.5 g of purified water was used without using methylpolysiloxane.

<Comparative Example 2>
A composition was obtained in the same manner as in Example 1 except that no fatty acid ester was used and 10 g of purified water was used.

<Comparative Example 3>
A composition was obtained in the same manner as in Example 1 except that 56.6 g of purified water was used without using fatty acid ester, methylpolysiloxane and liquid paraffin.

The compositions obtained in Examples 1-4 and Comparative Examples 1-3 were tested for hatching in louse eggs.

[Lice egg hatching test]
The compositions obtained in Examples 1 to 4 and Comparative Examples 1 to 3 are applied to about 30 louse eggs, and after standing for 10 to 14 days, whether or not the louse eggs have hatched. was confirmed visually. Then, as the hatching inhibition rate, the ratio of the number of unhatched louse eggs to the number of louse eggs used in the test was calculated by (Equation 1). A composition with a hatching inhibition rate of 70% or more was judged to be good.
Hatch inhibition rate (%) = {(number of louse eggs that did not hatch)/(number of louse eggs used in the test)} (Formula 1)
Regarding the hatching of the louse eggs treated with each composition, the presence or absence of hatching was confirmed based on the day when 90% or more of the approximately 30 louse eggs, which were controls not treated with the composition, had hatched. , the percentage of hatching in the control was used as a correction factor to calculate the corrected percentage of inhibition of hatching.

As a result, the compositions obtained in Examples 1-4 had a corrected hatching inhibition rate of 93-100%, while the compositions obtained in Comparative Examples 1-3 had a corrected hatching inhibition rate of 48-65%.

These results are shown in Table 1.

As shown in Table 1, in Examples 1 to 4, since the fatty acid ester isopropyl palmitate and the siloxane methylpolysiloxane are used in combination, the corrected hatching inhibition rate is 93 to 100%, which is almost complete. hatching could be inhibited. On the other hand, in Comparative Examples 1 to 3, since at least one of isopropyl palmitate and methylpolysiloxane was not blended, the hatching inhibition rate was 48 to 65%, which was only about half of the hatching of lice. From this, it was clarified that the synergistic effect of the fatty acid ester and siloxane exerts an effect of remarkably suppressing hatching of lice from lice eggs.

Claims (1)

0.1 to 40% by weight of a fatty acid ester that is isopropyl palmitate or isopropyl myristate ;
0.1 to 40% by weight of siloxane that has a linear skeleton and is oily at room temperature of 25° C.;
0.1 to 40% by weight of a nonionic surfactant;
0.1 to 30% by weight of fatty acids having 12 to 18 carbon atoms;
0.1 to 30% by weight of an alcohol having 12 to 18 carbon atoms;
An agent for repelling louse eggs, characterized by containing 21 to 43.1% by weight of liquid paraffin .