JP2022049134A - Wet sheet - Google Patents

Abstract

To provide a wet sheet having high disinfecting/antibacterial effects, low irritability against skin, and a high use-satisfaction feeling.SOLUTION: A wet sheet of this invention includes a first surface and a second surface on the opposite side of the first surface, in which a liquid agent is carried in a fiber aggregate. The liquid agent includes: (A) one or more kinds among lactic acid, citric acid, malic acid, acetic acid, and salt thereof; (B) a quaternary ammonium salt-type surface-active agent; (C) a water-soluble fragrance; and (D) water. The liquid agent includes no ethanol and has pH of 3.0 or higher and lower than 6.0 at 25°C.SELECTED DRAWING: None

Description

The present invention relates to a wet sheet.

Wet sheets impregnated with a liquid agent are used for cleaning articles and cleaning the body.
The present applicant has proposed a sterilizing cleaning article obtained by impregnating a water-decomposable base sheet containing 80% by mass or more of cellulosic fibers with a liquid detergency composition (Patent Document 1). This cleaning article has both sterilization and strength.
Patent Document 2 discloses a disinfectant sheet impregnated with an aqueous disinfectant having a pH of 8.1 or more and 12.0 or less.

Japanese Unexamined Patent Publication No. 2017-110323 Japanese Unexamined Patent Publication No. 2018-27916

The cleaning article of Patent Document 1 has not been studied for improvement in usability by exhibiting a desired aromaticity at the time of use, and there is room for improvement in this respect.

In the disinfectant sheet described in Patent Document 2, since the impregnated aqueous disinfectant is alkaline, it is highly irritating when the disinfectant touches the skin of the user.

Therefore, the present invention relates to a wet sheet having a high sterilizing and antibacterial effect, low irritation to the skin, and a high usability.

The present invention has a first surface and a second surface located on the opposite side of the first surface.
The liquid agent is supported on the fiber aggregate,
The liquid agent contains the following components (A) to (D), and contains the following components (A) to (D).
(A) One or more of lactic acid, citric acid, malic acid, acetic acid and salts of these acids,
(B) Quaternary ammonium salt-type surfactant,
(C) water-soluble fragrance, and (D) water,
The liquid agent does not contain ethanol and is free of ethanol.
The liquid agent provides a wet sheet having a pH of 3.0 or more and less than 6.0 at 25 ° C.

According to the present invention, there is provided a wet sheet having a high sterilizing and antibacterial effect, low irritation to the skin, and a high usability.

Hereinafter, the present invention will be described based on the preferred embodiment thereof. The wet sheet of the present invention is a wet sheet in which a fiber aggregate is provided as a base material thereof and a liquid agent is supported on the fiber aggregate. The wet sheet of the present invention is, for example, a building such as a floor, a wall, a ceiling and a pillar, a fitting such as a shelf, a window glass, a mirror, a door and a doorknob, and a rigid equipment such as a desk, a dining table, a kitchen and a toilet, and other articles. It can be applied to cleaning the surface and cleaning the body. In the following description, unless otherwise specified, cleaning of a hard surface and cleaning of a body or the like are collectively referred to as "cleaning".

The wet sheet has a first surface and a second surface located on the opposite side of the first surface. Both the first surface and the second surface can be used as cleaning surfaces that come into contact with the surface to be cleaned when the wet sheet is used. The first and second surfaces are composed of fiber aggregates. Therefore, the first surface of the wet sheet is composed of the first surface of the fiber aggregate, and the second surface of the wet sheet is composed of the second surface of the fiber aggregate.

The fiber aggregate is held by at least one of entanglement, joining and fusion of fibers. As the form of the fiber aggregate, for example, the fibers may be entangled or fused with each other to form an integral fiber aggregate, or a plurality of fiber layers may be entangled, bonded or fused and integrated. good. The wet sheet may be composed of only the fiber aggregate as the base material, or may further include other sheet materials, other members such as scrimnet, or both in addition to the fiber aggregate. good. Details of the fiber aggregate will be described later.

The wet sheet of the present invention has one of the characteristics in the composition of the liquid preparation. The liquid preparation contains (A) one or more of (A) lactic acid, citric acid, malic acid, acetic acid and salts of these acids, (B) a quaternary ammonium salt type surfactant, and (C). Contains water-soluble fragrance and (D) water. That is, the liquid agent is an aqueous liquid containing the components (A) to (D).

As described above, the liquid preparation is composed of the component (A) containing one or more of lactic acid, citric acid, malic acid, acetic acid and salts of these acids. The component (A) has a function of exerting a sterilizing action and an antibacterial action on the surface to be cleaned after cleaning. In the following description, the component (A) is also referred to as "organic acid or the like".

As used herein, "sterilization" means that microorganisms existing on the surface to be cleaned are physically removed by a fiber aggregate or a liquid agent by cleaning with a wet sheet, and the microorganisms are chemically removed by the components in the liquid agent. Includes aspects of inactivating and removing or detoxifying. Further, the term "antibacterial" as used herein means suppressing the growth of microorganisms present on the surface to be cleaned.

Of the above-mentioned component (A), from the viewpoint of effectively exhibiting antibacterial and antibacterial performance after cleaning, it is highly safe even when the liquid agent comes into contact with the body, and it is easy to remind the user of the sheet of security. It is preferable to use at least lactic acid or a salt thereof as the component (A), and it is further preferable to use only lactic acid or a salt thereof as the component (A). Examples of the counterion constituting the salt include alkali metal ions such as potassium and sodium.
When a component in which an optical isomer is present is used as the component (A), it may be an L-form, a D-form, a mixture of optical isomers, or a racemic as long as the above-mentioned functions are exhibited. It may be a body.

When lactic acid or a salt thereof is contained as the component (A), a synthetic product may be used as the lactic acid or a salt thereof, and fermented lactic acid or a salt thereof, which is an extracted and purified product of lactic acid produced by fermentation of a microorganism such as lactic acid bacteria, is used. May be good. Of these, it is more preferable to use fermented lactic acid or a salt thereof from the viewpoint of reminding the user of the sheet of a good image of fermented food or the like and further enhancing the user's sense of security.

The liquid agent is composed of a quaternary ammonium salt-type surfactant which is a kind of cationic surfactant as a component (B). Since the component (B) has a wide antibacterial spectrum, it has a function of exerting a sterilizing action and an antibacterial action against various microorganisms. In addition to this, it also has a function of improving the removability of dirt on the surface to be cleaned.

As the component (B), what is generally known as inverted soap can be used, and specific examples thereof include benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetylpyridinium chloride, cetalconium chloride, and didecylchloride. Includes one or more of dimethylammonium, hexadecyltrimethylammonium bromide, dofanium chloride, tetraethylammonium bromide, domiphen bromide and benzalkonium cetylphosphate. Benzalkonium chloride and chloride from the viewpoint of effectively expressing the antibacterial and antibacterial action, reducing the irritation to the skin when the liquid is in contact with the user's skin, and improving the stability of the liquid. It is preferable to use one or two of benzethonium, and it is more preferable to use benzalkonium chloride.

The liquid agent contains a water-soluble fragrance as the component (C). The component (C) has a function of expressing a fragrance when the sheet is used and in the space to be cleaned or the space where the surface to be cleaned is present after cleaning to improve the usability of the sheet. It also has a function of masking the odor derived from the constituents of the fiber aggregate and the liquid agent to improve the usability of the sheet. The liquid agent contained in the wet sheet is an aqueous solution, but by using a water-soluble liquid as the fragrance, it is advantageous in that the dispersion stability of the liquid agent component can be improved without separating the fragrance component from the liquid agent. Is.

The fragrance used as the component (C) may be either a compounded fragrance or a natural fragrance as long as the component is water-soluble. Specifically, "Basic knowledge of fragrances and fragrances" (edited by Motoki Nakajima, Sangyo Tosho Co., Ltd., first edition, June 21, 1995), "Synthetic fragrances-chemicals and product knowledge" (edited by the synthetic fragrance editorial committee, The fragrances and the like described in "Perfume and Flavor Chemicals" (written by Stephen Arctender, self-funded publication, 1969) can be used. Regardless of the fragrance, as the fragrance component contained in the component (C), a fragrance that volatilizes in the atmosphere under atmospheric pressure and can perceive the fragrance in an environment of normal temperature and pressure is used. be able to. As such a fragrance, for example, one having a fragrance such as rose, lavender, rosemary, jasminum, or Iran-Iran can be used.

The water-soluble fragrance used as the component (C) is preferably a steam-distilled herb. Further, it is also preferable to use the water-soluble fragrance in the form of an aqueous solution containing a water-soluble fragrance component. Further, if necessary, components such as preservatives and solvents may be added to adjust the composition of the water-soluble fragrance. By using such a water-soluble fragrance, the dispersion stability in the liquid preparation can be enhanced, and the fragrance can be efficiently expressed when the sheet is used. In addition to this, since the herbs are natural products, it is possible to make the user of the sheet perceive that the extract component derived from the natural product is contained, and to make it easier for the user to remind the user of a sense of security. Examples of herbs include anise, basil, bergamot, kusunoki, chamomile, cloves, eucalyptus, rose, jasmine, lavender, Iran Iran, mint, sage, rosemary and the like.

The liquid agent contains water as the component (D). By containing water, each component of the above-mentioned liquid preparation is uniformly dispersed and supported on the fiber aggregate to maintain the stability of the liquid preparation, and the sterilizing antibacterial performance and the component (B) by the components (A) and (B). It has a function of expressing a pleasant fragrance due to C). Examples of water include tap water, distilled water, purified water, ion-exchanged water and the like. Distilled water, purified water or ion-exchanged water is preferable.

The liquid preparation containing the above-mentioned components (A) to (D) does not contain ethanol. By not containing ethanol, even when the liquid agent comes into contact with the user's skin when using the wet sheet, the irritation to the skin is reduced and the usability is further improved. The absence of ethanol includes both the absence of ethanol in the liquid and the inevitable mixing of ethanol in the liquid. More specifically, if the ethanol content in the liquid preparation is less than 0.005% by mass, it is said that "ethanol is not contained".
In order to make the liquid preparation free of ethanol, for example, a raw material containing no ethanol as a constituent raw material of the liquid preparation may be used as a constituent raw material of the liquid preparation, or the above-mentioned content of ethanol from the raw material containing ethanol may be used. After removing until it becomes less than, a liquid preparation may be prepared using the raw material.
The ethanol content can be measured, for example, by gas chromatography.

The liquid agent preferably has an acidic pH at 25 ° C. Specifically, the pH of the liquid at 25 ° C. is preferably 3.0 or higher, more preferably 4.0 or higher, still more preferably 4.3 or higher, preferably 6.0 or lower, and more preferably 5.5. Below, it is more preferably 5.0 or less. When the liquid agent has such a pH, the irritation to the skin when the liquid agent comes into contact with the user's skin is reduced, and the sterilizing and antibacterial performance of the component (A) and the component (B) is sufficiently exhibited. Can be made to.
In order to adjust the pH of the liquid agent to the above range, for example, the contents of the component (A) and the component (B) may be changed, or an inorganic acid such as hydrochloric acid or sulfuric acid or an inorganic acid such as an alkali metal hydroxide may be used. A base may be added.

In the present technical field, an inverted soap such as a quaternary ammonium salt type surfactant may be used for the purpose of disinfecting the surface to be cleaned and antibacterial. When such a surfactant is used alone, if there is a stain containing a protein on the surface to be cleaned, the sterilizing antibacterial agent is caused by the ionic interaction between the protein and the quaternary ammonium salt-type surfactant. Performance may be diminished and the desired sterilization and sterilization effect may not be achieved. In addition, when the quaternary ammonium salt surfactant is used alone, it is necessary to remove stains containing proteins in advance in order to fully develop the sterilizing and antibacterial performance, and it is necessary to clean the hard surface and clean the body. The wiping work can be complicated.

As a result of diligent studies by the present inventor in order to improve such a point, an organic acid or the like (component (A)) is contained in addition to the quaternary ammonium salt type surfactant (component (B)). Surprisingly, it was found that even in the presence of stains containing proteins, the antibacterial and antibacterial performance equal to or higher than that in the absence of stains containing proteins can be exhibited. This is advantageous in that the desired sterilizing and antibacterial performance can be sufficiently exhibited in a single operation when cleaning a hard surface or cleaning the body or the like.
It was also found that since the component (A) is typically a component contained in food, it is highly safe even when the liquid agent comes into contact with the body and can give a sense of security to the user of the sheet.
Further, even in the coexistence of the components (A) and (B), the effectiveness of each of the components (A) and (B) is not adversely affected, and the irritation to the skin can be reduced. It was also found that it is excellent in safety and can improve the feel of the surface to be cleaned after cleaning.

Therefore, the wet sheet having the above structure has an antibacterial and antibacterial effect by using the components (A) and (B) in combination, regardless of the type of the surface to be cleaned and the type of dirt adhering to the surface to be cleaned. It will be excellent. In addition to this, by setting the pH of the liquid agent to the acidic range and not containing ethanol, it is possible to reduce the irritation to the skin even when the liquid agent comes into contact with the user's skin, which is safe. Sex improves. Furthermore, by incorporating a water-soluble fragrance (component (C)) in the liquid agent, the dispersion stability of the supported liquid agent is enhanced, and the fragrance is effective on the surface to be cleaned and the surrounding space when the sheet is used and after the sheet is used. It can be expressed in a specific manner, and the feeling of use is high.

From the viewpoint of making the above-mentioned effects remarkable, the content of the component (A) in the liquid preparation is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and 1.0% by mass or less. Is preferable, and 0.5% by mass or less is more preferable. By setting the content of the component (A) in such a range, the sterilizing and antibacterial performance can be more effectively exhibited without unintentional precipitation of the components in the liquid preparation, and after cleaning. It is possible to improve the feel of the surface to be cleaned.
When salt is used as the component (A), the content of the component (A) is based on the amount converted into a molecular type acid. When two or more kinds of the component (A) are contained, the above-mentioned content is the total amount. The content of the component (A) can be measured, for example, with an absorptiometer.

The content of the component (B) in the liquid preparation is preferably 0.05% by mass or more, more preferably 0.075% by mass or more, still more preferably 0.1% by mass or more, and preferably 0.5% by mass. Below, it is more preferably 0.3% by mass or less, still more preferably 0.2% by mass or less. By setting the content of the component (B) to such a content, the sterilizing and antibacterial performance can be further enhanced, and the stain removing property of the surfactant can be further enhanced. When two or more kinds of the component (B) are contained, the content of the component (B) is the total amount. The content of the component (B) can be measured, for example, by liquid chromatography.

The mass ratio of the content of the component (A) to the content of the component (B) in the liquid preparation [component (A) / component (B)] is preferably 1 or more, more preferably 3 or more, and preferably 10 or more. Below, it is more preferably 5 or less. By setting such a mass ratio, the stability of the liquid agent can be sufficiently maintained, excellent sterilizing and antibacterial performance can be exhibited, and the roughness of the surface to be cleaned after cleaning can be reduced to be cleaned. The texture of the surface can be further improved.

The content of the component (C) in the liquid preparation is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, from the viewpoint of achieving both the expression of aromaticity at the time of use and the stability of the liquid preparation. Yes, preferably 5% by mass or less, more preferably 1% by mass or less. The content of the component (C) is based on the component mass of the water-soluble fragrance. When two or more kinds of the component (C) are contained, the content of the component (C) is the total amount.

The content of the component (D) in the liquid preparation is preferably 97% by mass or more from the viewpoint of uniformly supporting the liquid preparation on the fiber aggregate and improving the stability and dispersibility of the constituent components of the liquid preparation. It is more preferably 98% by mass or more, preferably 99.7% by mass or less, and more preferably 99.5% by mass or less. The content of the component (D) can be calculated, for example, from the difference between the mass of the wet sheet in a wet state and the mass of the sheet in an absolutely dry state.

It is preferable that the wet sheet does not contain silicone in the liquid agent, depending on the desired operability and usability.
Specifically, from the viewpoint of exhibiting the effect of making the target surface less slippery after wiping with a wet sheet, it is preferable that the liquid agent does not contain silicone. When silicone is not contained in the liquid agent, silicone does not remain on the hard surface, so that it is particularly suitable when the wet sheet is used for cleaning a hard surface such as a floor or a wall.

In addition to the above-mentioned components, the liquid may further contain other components usually used in the art. Examples of such other components include pH adjusters, polyhydric alcohols, preservatives, pigments and the like. These components can be used alone or in combination of two or more. The total content of these in the liquid preparation is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, preferably 2.7% by mass or less, and more preferably 1.2% by mass or less.

Examples of the pH adjuster include inorganic acids such as hydrochloric acid and sulfuric acid, inorganic bases such as sodium hydroxide and potassium hydroxide, and organic bases such as triisopropanolamine.
Examples of the polyhydric alcohol include dihydric alcohols such as 1,3-butylene glycol, propylene glycol and dipropylene glycol, and trihydric alcohols such as glycerin.
Examples of the preservative include benzoic acid and salts thereof, parabens such as alkyl paraoxybenzoate and benzyl paraoxybenzoate, phenoxyethanol, ethylhexanediol and the like.

The liquid agent contains a quaternary ammonium salt surfactant as the component (B), and may contain a surfactant other than the component (B) as long as the effect of the present invention is exhibited. As the surfactant other than the component (B), a cationic surfactant other than the quaternary ammonium salt, an anionic surfactant, and an amphoteric surfactant may be contained. Examples of the amphoteric surfactant include polyoxyethylene lauryl ether. The content of these surfactants in the liquid preparation is preferably not contained from the viewpoint of further reducing the irritation to the skin.
On the other hand, from the viewpoint of further enhancing the stain removability, the content of the surfactant other than the component (B) in the liquid preparation is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and It is preferably 1.0% by mass or less, and more preferably 0.3% by mass or less.
In addition to this, from the viewpoint of further reducing the irritation to the skin when the liquid agent comes into contact with the skin, the content of the surfactant as a whole including the component (B) in the liquid agent is 1.0. It is preferably mass% or less.

The fiber aggregates constituting the wet sheet will be described below. Examples of the fiber constituting the fiber aggregate include one or more of natural fiber, synthetic resin fiber, regenerated fiber and the like, and preferably include a fiber having hydrophilicity.

Examples of the natural fiber include one or more of natural cellulose fibers such as pulp, cotton and hemp.
Examples of the synthetic resin fiber include polyolefin fibers such as polyethylene (PE) and polypropylene (PP), polyester fibers such as polyethylene terephthalate (PET), PE and PET, and two or more types such as PE and PP, PP and PET. Mixed resin fibers containing components, composite fibers such as core-sheath fibers or side-by-side fibers having two or more components, polyamide fibers such as nylon 6 and nylon 66, vinyl fibers such as polyvinyl chloride and polystyrene, polyacrylonitrile and the like. Examples thereof include one or more of acrylic fibers, fluororesin fibers such as polyperfluoroethylene, and biodegradable fibers such as polylactic acid.
Examples of the regenerated fiber include one or more of rayon, cupra, acetate fiber lyocell and the like, and rayon is preferable.

Further, as the fiber aggregate, a non-woven fabric, a woven fabric, a knitted fabric or the like containing the above-mentioned fibers may be used. When a non-woven fabric is used as the fiber aggregate, spunlace non-woven fabric, melt blown non-woven fabric, spunbond non-woven fabric, air-through non-woven fabric, resin bond non-woven fabric, needle punch non-woven fabric and the like can be used. Moreover, you may use the composite of these non-woven fabrics.

From the viewpoint of improving the texture of the wet sheet, improving the supportability of the liquid agent, and having the strength and flexibility of the sheet, the fiber aggregate preferably contains at least regenerated fibers, and preferably contains at least rayon fibers as the regenerated fibers. It is more preferable to contain recycled fiber and synthetic resin fiber, and it is further preferable to contain rayon fiber and synthetic resin fiber.

Explaining the arrangement position of the fiber in the wet sheet, it is preferable that the fiber aggregate constituting the wet sheet contains regenerated fiber and synthetic resin fiber on at least one surface thereof. With such a configuration, in addition to further improving the texture of the wet sheet, the supportability of the liquid agent, and the strength and flexibility of the sheet cleaning surface, the liquid agent is efficiently supplied to the surface to be cleaned and sterilized. The antibacterial performance can be exhibited more effectively.

When the fiber aggregate has the above-mentioned morphology, the fiber aggregate has, for example, (i) regenerated fibers and synthetic resin fibers present only in the region including at least one of the first surface and the second surface, and the sheet thickness. In the region other than the region in the direction, only regenerated fibers, only synthetic resin fibers, or fibers other than these fibers may be present. Alternatively, the fiber aggregate may contain the regenerated fiber and the synthetic resin fiber in the entire area in the sheet thickness direction including, for example, (ii) at least one of the first surface and the second surface.

When the fiber aggregate is the embodiment (i), it is more preferable that the fiber aggregate has a multi-layer structure composed of a plurality of fiber layers. Specifically, the fiber aggregate is a third fiber arranged adjacent to the first fiber layer including the first surface, the second fiber layer including the second surface, and the first fiber layer and the second fiber layer. It is preferably composed of a three-layer structure with layers. The first fiber layer and the second fiber layer are configured by entwining recycled fibers and synthetic resin fibers, respectively. The third fiber layer contains synthetic resin fibers, and the fibers are fused to each other.
With such a configuration, it is possible to secure sufficient strength to withstand the actual use of the sheet. In addition to this, since the third fiber layer plays a role like a tank for holding the liquid agent, the supportability of the liquid agent on the sheet can be further improved. Further, since the liquid agent supported on the wet sheet can be easily supplied from the third fiber layer to the surface to be cleaned via the first and second fiber layers, the cleaning liquid can be continuously and continuously applied to the surface to be cleaned. By continuously supplying the liquid, the sustained release property can be enhanced, and the stain removing performance and the sterilizing antibacterial performance on the surface to be cleaned can be more effectively and widely exhibited. A sheet having such a configuration can be suitably used when a single sheet is used to clean a large area of a surface to be cleaned. In particular, in this embodiment, stains containing proteins and oils can be removed by dissolving or dispersing them in a liquid agent, and fine particles such as dust and stains such as hair can be removed by entwining fibers with fibers, so that hard surfaces such as floors and walls can be removed. Especially suitable for cleaning.

When the fiber aggregate has a multi-layer structure, the boundary surface of each fiber layer may be clearly present, or the boundary surface of each fiber layer may be unclearly present. In any case, when the fiber aggregate in the wet sheet is viewed along the thickness direction, the abundance ratio of the constituent fibers in each fiber layer changes stepwise, continuously, or in a combination thereof. It is preferable to have.
When the fiber aggregate has a multi-layer structure, the fibers existing in each fiber layer, preferably the regenerated fibers and synthetic resin fibers existing in each fiber layer, may be independently of the same type of fiber. , May be different. The term "different types of fibers" includes not only cases where the constituents of the fibers are different, but also cases where the constituents of the fibers are the same but the thickness and physical composition of the fibers are different. When the physical composition of the fiber is different, for example, two kinds of synthetic resins of PE and PP are included as constituents of the fiber, one is a mixed resin fiber in which two kinds of synthetic resins are mixed, and the other is a mixed resin fiber. Examples thereof include a core-sheath fiber composed of a PP core and a PE sheath.

A wet sheet having a fiber aggregate composed of a plurality of fiber layers is, for example, after entwining, joining or fusing a laminate in which non-woven fabrics corresponding to each fiber layer are laminated to form a fiber aggregate. , The fiber aggregate can be obtained by impregnating the liquid agent. As the wet sheet having the first to third fiber layers, for example, a spunlaced nonwoven fabric containing recycled fibers and synthetic resin fibers as the first fiber layer and the second fiber layer and entangled with water flow is used, and as the third fiber layer, It can be obtained by using an air-through non-woven fabric containing synthetic resin fibers and fused with each other, passing a laminate of these non-woven fabrics through a heat roll, embossing the fibers, and joining the fiber layers.

When the fiber aggregate is the embodiment (ii), it is preferable that the fiber aggregate is composed of a single fiber layer. With such a configuration, the flexibility of the sheet can be further enhanced, the sheet can be easily followed by the surface to be cleaned, and the surface to be cleaned can be efficiently cleaned and the antibacterial property can be efficiently exhibited. It can be carried out. A sheet having such a configuration can be suitably used for cleaning when the surface to be cleaned is a curved surface, an uneven surface, or a flexible surface, and can be used to clean the body such as human hands, face, and mouth. Is particularly suitable for.
As the fiber aggregate having a single fiber layer, for example, a spunlace nonwoven fabric in which recycled fibers and synthetic resin fibers are entangled with water flow and the fibers are entangled with each other can be used alone.

From the viewpoint of enhancing the supportability of the liquid agent and preventing unintentional drying of the wet sheet while ensuring sufficient strength to withstand the use of the wet sheet, the basis weight of the fiber aggregate constituting the wet sheet is preferably 20 g / g. m ² or more, more preferably 30 g / m ² or more, still more preferably 40 g / m ² or more, preferably 200 g / m ² or less, more preferably 150 g / m ² or less, still more preferably 100 g / m ² or less. be.

From the viewpoint of improving the strength and flexibility of the sheet, the thickness of the fiber aggregate is preferably 0.8 mm or more, more preferably 0.9 mm or more, and preferably 1.5 mm or less under a load of 40 N / m ² . It is more preferably 1.3 mm or less. The thickness of the fiber aggregate can be measured with respect to the fiber aggregate in an absolutely dry state obtained by drying the wet sheet, for example, using a laser displacement meter or the like.

From the viewpoint of achieving both the removal property of stains by the liquid agent and the antibacterial performance at a high level, the ratio of the liquid agent carried on the fiber aggregate is 100% by mass with respect to the mass of the fiber aggregate in the absolutely dry state. The above is preferable, 200% by mass or more is more preferable, 1000% by mass or less is preferable, and 500% by mass or less is further preferable.

The fiber diameter of the fibers contained in the fiber aggregate is preferably 5 μm or more, more preferably 10 μm or more, preferably 25 μm or less, still more preferably 20 μm or less. When a plurality of different types of fibers are contained in the fiber aggregate, each fiber shall independently satisfy the above range. The fiber diameter of the fiber can be an arithmetic mean value measured by using a scanning electron microscope or the like for the longest length in the fiber cross section orthogonal to the fiber length direction for 10 or more fibers.

Regardless of the form of the fiber aggregate described above, the ratio of the regenerated fiber to the entire fiber aggregate is preferably 50% by mass or more, preferably 70% by mass or more, from the viewpoint of preventing unintentional drying of the wet sheet. Is more preferable, and 100% by mass or less is preferable, and 90% by mass or less is more preferable.

The wet sheet can be used alone or by attaching the sheet to a cleaning tool such as a wiper. Wet wipes can typically be disposable.
The wet sheet can be, for example, a single-wafer sheet having a predetermined size. In this case, it can be manufactured or distributed as a package house in a packaging bag or a packaging container in a state where a plurality of sheet sheets are laminated. Such a wet sheet can be used alone or by attaching the sheet to a cleaning tool, such as a building such as a floor, a wall, a ceiling or a pillar, a fitting such as a shelf, a window glass, a mirror, a door or a doorknob, or a desk. It is suitably used for cleaning hard surfaces such as dining table, kitchen, toilet and other equipment and other articles.

The present invention also provides a method for improving the sterilizing antibacterial performance by the above-mentioned quaternary ammonium salt type surfactant. Specifically, an aqueous liquid containing a quaternary ammonium salt-type surfactant and water and containing no ethanol is mixed with an organic acid or the like, and the pH at 25 ° C. is preferably 3.0 or higher. A step of preparing a liquid preparation having a value of less than 0 is provided. By bringing this liquid agent into contact with the surface to be cleaned, the antibacterial and antibacterial performance can be exhibited on the surface to be cleaned. The above-mentioned explanations are appropriately applied to the points not particularly described in this method.

Although the present invention has been described above based on the preferred embodiment thereof, the present invention is not limited to the above embodiment.

Hereinafter, the present invention will be described in more detail by way of examples. However, the scope of the invention is not limited to such examples. Unless otherwise specified in the table, the content of each component indicates mass%.

[Examples 1 to 14 and Comparative Examples 1 to 9]
A spunlace-air through-spanlace non-woven fabric (manufactured by Ikeda Paper Industry Co., Ltd., GTS65B) was used as the fiber aggregate. A wet sheet was produced by impregnating the liquid agent having the composition shown in Table 1 below at a ratio of 270% by mass with respect to the mass of the fiber aggregate. The fiber aggregate had a plan view dimension of 285 mm × 205 mm, a thickness of 1.1 mm, and a basis weight of 65 g / m ² .
This fiber aggregate has a three-layer structure, and 50% by mass of rayon fiber (fiber diameter: about 15 μm) and 25% by mass of synthetic resin fiber made of acrylic nitrile resin (fiber diameter: about 10 μm) and 25% by mass. Polypropylene / polyethylene (1: 1) resin synthetic resin fibers (fiber diameter: about 10 μm) are entangled in a first fiber layer made of a spunlace non-woven fabric, and a spunlace non-woven fabric having the same composition as the first fiber layer. It was composed of a second fiber layer and a third fiber layer made of an air-through non-woven fabric in which synthetic resin fibers (fiber diameter: about 12 μm) made of polyester / polyethylene resin were arranged between these fiber layers and fused to each other. .. The first fiber layer constituted the first surface, and the second fiber layer formed the second surface.

Details of the components of the liquid preparation used in each Example and Comparative Example are shown below.
<Ingredient (A)>
・ Lactic acid: Fermented lactic acid, product number PURAC ULTRAPURE90, manufactured by Purac Thailand ・ Citric acid: manufactured by Fuso Chemical Industry Co., Ltd. ・ Malic acid: manufactured by Fuso Chemical Industry Co., Ltd. ・ Acetic acid: manufactured by Wako Pure Chemical Industry Co., Ltd. ・ Succinic acid: Made by Genuine Chemical Co., Ltd. <Ingredient (B)>
-Quaternary ammonium salt type surfactant: Sanizol C, manufactured by Kao Corporation <Ingredient (C)>
-Water-soluble fragrance: Rosemary steam distilled product (K / EHP manufactured by Koei Kogyo Co., Ltd .; an aqueous solution containing 89% by mass of rosemary-derived fragrance component)
<Component (D)>
・ Water: Ion-exchanged water <Other components>
・ Surface active agent: Emargen 109P, manufactured by Kao Co., Ltd. ・ Na benzoate: manufactured by Fushimi Pharmaceutical Co., Ltd. ・ Polyhydric alcohol: propylene glycol, manufactured by ADEKA Co., Ltd. ・ Polyhydric alcohol: dipropylene glycol, manufactured by ADEKA Co., Ltd. ・ pH Adjuster: Sodium hydroxide, manufactured by Nankai Chemical Co., Ltd. ・ pH adjuster: sulfuric acid, manufactured by Wako Pure Chemical Industries, Ltd. ・ Ethanol: manufactured by Wako Pure Chemical Industries, Ltd. ・ Oil-soluble fragrance: U-CQCX-1 (Kao Co., Ltd.) Made)

[Measurement of pH of liquid]
For the wet sheets of Examples and Comparative Examples, the supported liquids were extracted, and the pH at 25 ° C. was measured using LAQUA F-72 manufactured by HORIBA, Ltd. The results are shown in Table 1.

[Evaluation of sterilization performance by sterilization test]
Wet sheets of Examples and Comparative Examples were evaluated according to the "sterilization performance test of wet wipers" established by the Japan Clean Paper and Cotton Industry Association.
Escherichia coli and Staphylococcus aureus were selected as bacterial species. The viable cell count of each bacterium was adjusted to 1.0 to 5.0 × 10 ⁹ cells / mL. 0.01 mL of each bacterium preparation solution was added dropwise on the stainless steel plate. This plate was wiped and cleaned using the wet sheets of Examples and Comparative Examples. The cleaning operation was performed by reciprocating 5 times on the plate at intervals of about 1 second with a load of 150 g applied to the wet sheet. After the wiping operation was completed, the wet sheet was left for 5 minutes, then transferred to a stomacher bag, and the bacteria were washed out under predetermined conditions. The cells were further diluted under predetermined conditions, inoculated into SCDLP agar medium for general bacteria, and cultured at 35 ° C. for 1 day. After culturing, the viable cell count was measured, and the common logarithmic value of the cell count was set to [B]. Further, the same operation was performed using the control sheet, and the measured logarithmic value of the number of bacterial cells was defined as [A]. As the control sheet, a sheet obtained by impregnating the fiber aggregates used in each Example and Comparative Example with only purified water was used.

The sterilization activity value was quantified by the following calculation formula (1), and the sterilization performance was evaluated according to the following criteria. The sterilization activity value is 2.0 or more, and the higher the value, the higher the sterilization performance. The results are shown in Table 1.
Sterilization activity value = [A]-[B] ... (1)
[A]: Arithmetic mean value of the viable cell count in the results of three trials on the control sheet [B]: The arithmetic mean value of the viable cell count in the results of three trials on the wet sheets of Examples and Comparative Examples. Arithmetic mean

<Evaluation criteria for sterilization performance>
a: The sterilization activity value is 3.0 or more, and the sterilization performance is excellent.
b: The sterilization activity value is 2.0 or more and less than 3.0, and the sterilization performance is good.
d: The sterilization activity value is less than 2.0, and the sterilization performance is inferior.

[Evaluation of antibacterial performance by antibacterial test (1): Normal test]
Wet sheets of Examples and Comparative Examples were evaluated in accordance with JIS Z2801 "Antibacterial Processed Product-Antibacterial Test Method / Antibacterial Effect".
Escherichia coli and Staphylococcus aureus were selected as bacterial species. A sample plate having a size of 5 cm × 5 cm made of polyethylene resin was wiped back and forth twice with the wet sheets of Examples and Comparative Examples, and then dried. Each bacterial solution was dropped onto the surface of each dried sample plate and inoculated. The number of inoculum was adjusted to 1.0 to 4.0 × 10 ⁵ per sample plate. A polyethylene film was placed so as to be in close contact with the bacterial solution on the sample plate. The size of the film was 4 cm x 4 cm. Then, the cells were cultured for 24 hours in an environment with a temperature of 35 ° C. and a relative humidity of 90% or more. It was transferred to a stomacher bag and the bacteria were washed out under the prescribed conditions. Further, it was diluted under predetermined conditions, inoculated into SCDLP agar medium for general bacteria, and cultured at 35 ° C. for 1 day. After culturing, the viable cell count was measured, and the common logarithmic value of the cell count was defined as [D]. Further, the same operation was performed using the control sheet, and the measured logarithmic value of the number of bacterial cells was defined as [C]. As the control sheet, a sheet obtained by impregnating the fiber aggregates used in each Example and Comparative Example with only purified water was used.

The antibacterial activity value was quantified by the following formula (2), and the antibacterial performance was evaluated according to the following criteria. The antibacterial activity value is 2.0 or more, and the higher the value, the higher the antibacterial performance. The results are shown in Table 1.
Antibacterial activity value = [C]-[D] ... (2)
[C]: Arithmetic mean value of the viable cell count in the results of three trials on the control sheet [D]: The arithmetic mean value of the viable cell count in the results of three trials on the wet sheets of Examples and Comparative Examples. Arithmetic mean

<Evaluation criteria for antibacterial performance>
a: The antibacterial activity value is 3.0 or more, and the antibacterial performance is excellent.
b: The antibacterial activity value is 2.0 or more and less than 3.0, and the antibacterial performance is good.
d: The antibacterial activity value is less than 2.0, and the antibacterial performance is inferior.

[Evaluation of antibacterial performance by antibacterial test (2): Contamination condition test]
With reference to JIS Z2801 "Antibacterial processed product-Antibacterial test method / antibacterial effect", an antibacterial test method was prepared and evaluated when dirt adhered to the surface to be cleaned. The difference from the conventional JIS Z2801 method is that 0.3% concentration of bovine serum albumin is added when preparing the bacterial solution. By adding albumin, the antibacterial property to the surface to be cleaned with protein-containing stains, which could not be evaluated by JIS Z2801 "Antibacterial processed product-Antibacterial test method / antibacterial effect", can be evaluated. The other test procedures and the evaluation of the antibacterial performance were carried out in the same manner as the method of [Evaluation of antibacterial performance by antibacterial test (1)].
In this evaluation, when the antibacterial activity value is 2.0 or more, the antibacterial effect is exhibited even in the presence of protein stains, and the antibacterial ability is the result obtained in [Evaluation of antibacterial performance by antibacterial test (1)]. When the antibacterial property is higher and the antibacterial activity value is 3.0 or more, it means that the antibacterial property is even higher. The results are shown in Table 1 below.

[Evaluation of skin irritation]
Using the wet sheets of Examples and Comparative Examples, the backs of the hands of three specialized panelists were reciprocated once per second for a total of three reciprocations, and the wiped portion was dried.
Separately, using the wet sheets of the examples and comparative examples, wipe the mouth area of three specialized panelists once per second for 5 turns in a circle around the mouth, and dry the wiped part. I let you.
Each of the back of the hand and the area around the mouth, which are the parts to be cleaned, were evaluated in consultation with expert panelists according to the following evaluation criteria. The results are shown in Table 1.
<Evaluation criteria for skin irritation>
b: There is no discomfort such as tension or dryness on the skin after wiping with a sheet, and the irritation to the skin is low.
d: There is a feeling of discomfort such as a feeling of tension or dryness on the skin after wiping with a sheet, and there is a possibility that it may be irritating to the skin.

[Evaluation of liquid formulation stability]
The stability of the liquids impregnated in the wet sheets of Examples and Comparative Examples was evaluated by the following methods.
Specifically, 100 ml of the liquid is placed in a 100 ml standard bottle and stored at 5 ° C, 20 ° C, 35 ° C, and 40 ° C for 20 days, and the appearance of the liquid is visually evaluated and the viscosity using a B-type viscometer is used. Measurements were performed respectively. The visual evaluation was performed according to the following criteria. The results are shown in Table 1.
<Evaluation criteria for liquid agent stability>
a: In the liquid preparation after 20 days, the appearance and viscosity do not change at any temperature, and the liquid preparation is excellent in stability.
d: In the liquid preparation after 20 days, a change in appearance or viscosity occurs at any temperature, the homogeneity of the liquid preparation cannot be maintained, and the stability of the liquid preparation is inferior.

[Evaluation of aroma after use]
Using the wet sheets of Examples and Comparative Examples, the usability associated with fragrance was evaluated by the following method.
Specifically, the wet sheets of Examples and Comparative Examples are attached to a wiper (Quickle wiper, manufactured by Kao Corporation), and the floor (Woody 45, manufactured by Panasonic Corporation) is cleaned for 1 tatami mat (range of 180 cm x 90 cm). The feeling of use associated with the aroma when wiped was evaluated. The results are shown in Table 1.
<Evaluation criteria for usability associated with fragrance>
a: A pleasant fragrance can be perceived both during and after use, and the feeling of use of the sheet is excellent.
b: The fragrance is not felt so much or it is odorless, and the usability of the sheet is inferior.
d: The aroma is too strong and the feeling of use of the sheet is inferior.

As shown in Table 1, it can be seen that the wet sheets of the examples have high sterilizing ability and high antibacterial ability against Escherichia coli and Staphylococcus aureus, respectively. In addition, it can be seen that all of the wet sheets of the examples have low skin irritation. Further, it can be seen that the wet sheet of the embodiment can satisfactorily perceive the pleasant fragrance of the fragrance both during and after use of the sheet, and is excellent in usability.
On the other hand, the wet sheet of the comparative example had a weak sterilizing effect or a high irritation to the skin.
From the above, the wet sheet of each example has both a high antibacterial and antibacterial effect and low irritation to the skin, and is excellent in usability.

Claims (11)

It has a first surface and a second surface located on the opposite side of the first surface.
The liquid agent is supported on the fiber aggregate,
The liquid agent contains the following components (A) to (D), and contains the following components (A) to (D).
(A) One or more of lactic acid, citric acid, malic acid, acetic acid and salts of these acids,
(B) Quaternary ammonium salt-type surfactant,
(C) water-soluble fragrance, and (D) water,
The liquid agent does not contain ethanol and is free of ethanol.
The liquid agent is a wet sheet having a pH of 3.0 or more and less than 6.0 at 25 ° C. The wet sheet according to claim 1, wherein the water-soluble fragrance is a steam distilled product of herbs. The wet sheet according to claim 1 or 2, wherein the liquid agent contains 97% by mass or more and 99.7% by mass or less of water. The wet sheet according to any one of claims 1 to 3, wherein the liquid agent does not contain silicone. The wet sheet according to any one of claims 1 to 4, wherein the liquid agent is supported by 100% by mass or more and 1000% by mass or less with respect to the mass of the fiber aggregate. The wet sheet according to any one of claims 1 to 5, wherein the fiber aggregate contains regenerated fibers. The wet sheet according to any one of claims 1 to 6, wherein the fiber aggregate contains a regenerated fiber and a synthetic resin fiber on at least one surface thereof. The fiber aggregate includes a first surface and has a first fiber layer in which regenerated fibers and synthetic resin fibers are entangled.
A second fiber layer containing a second surface and in which recycled fibers and synthetic resin fibers are entangled,
The wet according to any one of claims 1 to 6, which is adjacent to the first fiber layer and the second fiber layer, contains synthetic resin fibers, and has a third fiber layer formed by fusing the fibers to each other. Sheet. The wet sheet according to any one of claims 1 to 8, wherein the fiber aggregate has a basis weight of 40 g / cm ² or more and 100 g / cm ² or less. The wet sheet according to any one of claims 1 to 9, which is used by being attached to a cleaning tool. The wet sheet according to any one of claims 1 to 10, which is used for cleaning a hard surface.