阅读说明：本技术 护肤产品用的不织布 (Nonwoven fabric for skin care products ) 是由 小山久美 梶山宏史 中原诚 于 2018-06-20 设计创作，主要内容包括：本发明的课题在于提供一种制成护肤产品时的操作性优异、以及制成护肤产品时的对肌肤的密接性及附着于肌肤的化妆料的擦除性优异的护肤产品用的不织布。一种护肤产品用的不织布,包含单纤维直径为50nm以上且800nm以下的热塑性树脂纤维、以及依据JIS L 1015：2010 8.7.2而测定的拉伸强度为1.9cN/dtex以下的纤维素纤维,所述护肤产品用的不织布的特征在于,相对于所述护肤产品用的不织布的总质量的所述热塑性树脂纤维与所述纤维素纤维的合计含量为85质量％以上,所述热塑性树脂纤维与所述纤维素纤维的含有质量比(热塑性树脂纤维/纤维素纤维)为0.06～0.22。(The invention provides a non-woven fabric for skin care products, which has excellent operability when the non-woven fabric is prepared into the skin care products, and has excellent adhesion to skin and wiping performance of cosmetics attached to the skin when the non-woven fabric is prepared into the skin care products. A nonwoven fabric for skin care products, comprising thermoplastic resin fibers having a single fiber diameter of 50nm or more and 800nm or less, and a fiber having a fiber diameter according to JIS L1015: 20108.7.2 and a tensile strength of 1.9cN/dtex or less, wherein the nonwoven fabric for skin care products is characterized in that the total content of the thermoplastic resin fibers and the cellulose fibers is 85 mass% or more based on the total mass of the nonwoven fabric for skin care products, and the content mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is 0.06 to 0.22.)

1. A nonwoven fabric for skin care products, comprising thermoplastic resin fibers having a single fiber diameter of 50nm or more and 800nm or less, and a fiber-forming agent according to Japanese Industrial Standard L1015: 20108.7.2 and a tensile strength of 1.9cN/dtex or less, the nonwoven fabric for skin care products being characterized by:

the total content of the thermoplastic resin fibers and the cellulose fibers is 85 mass% or more based on the total mass of the nonwoven fabric for skin care products,

the mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is 0.06 to 0.22.

2. The nonwoven fabric for skin care products according to claim 1, wherein the thermoplastic resin fiber is a polyamide fiber.

3. The nonwoven fabric for skin care products according to claim 1 or 2, wherein the cellulose fiber is rayon.

4. The nonwoven fabric for skin care products according to any one of claims 1 to 3, wherein the fiber length of the cellulose fiber is 35mm or more.

5. A mask pack having a nonwoven fabric for a skin care product according to any one of claims 1 to 4.

6. A cleansing sheet having the nonwoven fabric for skin care products as claimed in any one of claims 1 to 4.

Technical Field

The present invention relates to a nonwoven fabric for skin care products.

Background

Sheet-like skin care cosmetics represented by facial masks or cleansing sheets are used for various purposes such as permeation of a drug solution into the skin or removal of a cosmetic material. The facial mask can keep the medicinal liquid on the surface of skin for a certain time, so that the medicinal liquid can sufficiently permeate into the skin compared with the existing skin care products directly coated on the skin. In addition, with regard to the cleansing sheet, a high cleansing effect can be obtained in terms of both the removal of the cosmetic with the cleansing agent and the removal effect caused by the contact of the sheet with the skin. As the above-mentioned excellent performance, various commercial products have been proposed as sheet-like skin care products.

Recently, it is known that: the wiping property of a cosmetic material adhered to the skin is improved by preparing a nonwoven fabric comprising polyester fibers having a filament diameter of 500nm to 1000nm and polyester fibers having a filament diameter of 10 μm to 100 μm, and immersing the nonwoven fabric in a cleanser or the like (patent document 1).

In addition, it is known that: a nonwoven fabric containing fibers having a filament diameter of 1nm to 500nm and containing a thermoplastic resin and fibers having a tensile strength of 2.0cN/dtex or more when wet is produced, and the nonwoven fabric is immersed in a cleanser or the like, whereby the nonwoven fabric is excellent in strength when wet and further improves the adhesiveness to the skin and the rub-off property of a cosmetic adhered to the skin (patent document 2).

Disclosure of Invention

Problems to be solved by the invention

The polyester fiber having a filament diameter of 10 to 100 μm included in the nonwoven fabric disclosed in patent document 1 (hereinafter, may be referred to as a known nonwoven fabric 1) has high tensile strength when wet. The known nonwoven fabric 1 contains 30 to 97 mass% of the fibers. Therefore, a skin care product obtained by impregnating the known nonwoven fabric 1 with a cleansing agent or a cosmetic material has a problem that the adhesion to the skin (particularly, the adhesion after a certain period of time has elapsed after the use of the skin care product) and the rub-off property of the cosmetic material adhering to the skin are not sufficient, although the skin care product has excellent strength when wet.

The nonwoven fabric disclosed in patent document 2 (hereinafter, may be referred to as a known nonwoven fabric 2) has the same problem as the known nonwoven fabric 1. That is, since the known nonwoven fabric 2 contains fibers having a high tensile strength in the wet state if the tensile strength in the wet state is 2.0cN/dtex or more, a skin care product obtained by impregnating the known nonwoven fabric 2 with a cleansing agent or a cosmetic material has a high strength in the wet state, but has a problem that the adhesion to the skin (particularly, the adhesion after a certain period of time has elapsed after the use of the skin care product) and the rub-off property of the cosmetic material adhering to the skin are not sufficient.

In view of the above problems, an object of the present invention is to provide a nonwoven fabric for skin care products which is excellent in handling properties when produced into a skin care product, and which is excellent in adhesion to the skin and wiping-off properties of cosmetics adhering to the skin when produced into a skin care product.

Means for solving the problems

In order to solve the above problem, the present invention has the following configuration. That is to say that the first and second electrodes,

(1) a nonwoven fabric for skin care products, comprising thermoplastic resin fibers having a single fiber diameter of 50nm or more and 800nm or less, and a fiber structure obtained by laminating a thermoplastic resin fiber according to Japanese Industrial Standard (JIS) L1015: 20108.7.2 and a tensile strength of 1.9cN/dtex or less, wherein the nonwoven fabric for skin care products is characterized in that the total content of the thermoplastic resin fibers and the cellulose fibers is 85 mass% or more based on the total mass of the nonwoven fabric for skin care products, and the content mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is 0.06 to 0.22,

(2) the nonwoven fabric for skin care products according to (1), wherein the thermoplastic resin fiber is a polyamide fiber,

(3) the nonwoven fabric for skin care products according to (1) or (2), wherein the cellulose fiber is rayon,

(4) the nonwoven fabric for skin care products according to (1) to (3), wherein the cellulose fibers have a fiber length of 35mm or more,

(5) a mask pack having a nonwoven fabric for a skin care product according to any one of (1) to (4),

(6) a cleansing sheet having a nonwoven fabric for skin care products according to any one of (1) to (4).

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a nonwoven fabric for skin care products which is excellent in handling properties when a skin care product is produced, and which is excellent in adhesion to the skin and wiping-off properties of cosmetics adhering to the skin when a skin care product is produced, can be provided by producing a nonwoven fabric for skin care products which comprises specific thermoplastic resin fibers and specific cellulose fibers, and further wherein the total content of the thermoplastic resin fibers and the cellulose fibers and the content mass ratio of the thermoplastic resin fibers and the cellulose fibers (thermoplastic resin fibers/cellulose fibers) are within specific ranges.

Detailed Description

Hereinafter, embodiments of the nonwoven fabric for skin care products of the present invention will be described in detail. The nonwoven fabric for skin care products of the present invention is a nonwoven fabric for skin care products comprising thermoplastic resin fibers having a single fiber diameter of 50nm or more and 800nm or less, and fibers prepared according to JIS L1015: 20108.7.2 has a tensile strength of 1.9cN/dtex or less. Further, in the nonwoven fabric for skin care products of the present invention, the total content of the thermoplastic resin fibers and the cellulose fibers is 85 mass% or more, and the content mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is 0.06 to 0.22. Further, the following may be in accordance with JIS L1015: 20108.7.2 is simply referred to as tensile strength. The total content of the thermoplastic resin fibers and the cellulose fibers is sometimes simply referred to as a total content. The content mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is sometimes simply referred to as the content mass ratio.

Further, the nonwoven fabric for skin care products of the present invention, which has the above-described structure, exhibits excellent strength when wet, and also excellent static friction coefficient, conformability, liquid retention property, and softness when compressed. The mechanism by which the nonwoven fabric for skin care products of the present invention exerts the above-described effects is presumed to be as follows. That is, as described above, the nonwoven fabric for skin care products of the present invention comprises: thermoplastic resin fibers having a filament diameter of 50nm to 800nm, which are extremely fine and have excellent flexibility; and cellulose fibers having a tensile strength of 1.9cN/dtex or less even in the case of cellulose fibers which tend to have a high level of tensile strength, and having appropriate flexibility and excellent water absorption properties; meanwhile, if the total content is 85 mass% or more, most of the nonwoven fabric for skin care products includes the thermoplastic resin fibers and the cellulose fibers, and if the content ratio is 0.06 to 0.22, the content ratio of the two types of fibers having different characteristics is specified as described above, and therefore, the nonwoven fabric for skin care products of the present invention is as follows: the nonwoven fabric for skin care products has a moderate tensile strength when wet, which is excellent in handling properties of skin care products formed using the nonwoven fabric, and also has excellent softness when wet (i.e., softness when compressed), conformability, and liquid retention properties. Further, according to the above characteristics, a skin care product (hereinafter, may be referred to as the present skin care product) using the nonwoven fabric for a skin care product of the present invention exhibits excellent followability to irregularities present on the surface of the skin (hereinafter, may be referred to simply as the skin) of the user when used, and can suppress the occurrence of a large gap between the present skin care product and the skin. Furthermore, since the nonwoven fabric for skin care products of the present invention contains thermoplastic resin fibers as ultrafine fibers in a specific amount, the thermoplastic resin fibers present on the surface of the nonwoven fabric for skin care products also penetrate into fine wrinkles present on the skin when the skin care products are used, and the contact area between the nonwoven fabric for skin care products and the skin becomes large, resulting in an excellent coefficient of static friction. Therefore, the skin care product is difficult to slide with the skin. Therefore, it is presumed that the excellent adherence and the excellent rub-off property of the skin care product can be exhibited by the excellent followability to the skin and the inhibition of slipping with the skin of the skin care product.

In addition, the skin care product using the nonwoven fabric for skin care products of the present invention is excellent in adhesion to the skin immediately after the skin care product is used, and also excellent in adhesion to the skin after a certain period of time has elapsed after the skin care product is used. Whether or not the adhesion to the skin is excellent after a certain period of time has elapsed since the skin care product was used can be evaluated by the adhesion to the skin after 20 minutes has elapsed since the skin care product was used (hereinafter, the adhesion may be abbreviated as adhesion after 20 minutes).

The nonwoven fabric for skin care products of the present invention comprises thermoplastic resin fibers having a single fiber diameter of 50nm to 800 nm. First, the thermoplastic resin fibers will be explained.

The thermoplastic resin fibers used in the nonwoven fabric for skin care products of the present invention are fibers having a single fiber diameter of 50nm to 800 nm. By setting the single fiber diameter of the thermoplastic resin fibers to 50nm or more, the thermoplastic resin fibers can be prevented from falling off and remaining on the skin when a skin care product using a nonwoven fabric for a skin care product is used. On the other hand, when the single fiber diameter is 800nm or less, the contact area between the skin and the surface of the nonwoven fabric for skin care products is increased as described above, and the friction coefficient between the skin and the nonwoven fabric for skin care products is increased, so that the nonwoven fabric for skin care products can be suppressed from slipping on the skin surface, and the nonwoven fabric for skin care products can be used to provide excellent adhesion and abrasion resistance of the skin care products. For this reason, the upper limit of the filament diameter of the thermoplastic resin fiber is more preferably 500nm or less, and still more preferably 300nm or less.

As the thermoplastic resin contained in the thermoplastic resin fiber used in the present invention, polyester, polyamide, polyolefin, or the like can be used. Among these, the thermoplastic resin fibers are preferably polyamide fibers in terms of improving the adhesiveness or the scratch resistance when wet. By using a polyamide fiber having water-absorbing property as the thermoplastic resin fiber having a single fiber diameter of 50nm or more and 800nm or less, the capillary effect of absorbing the chemical solution existing between the nonwoven fabric for skin care products and the skin is improved, and the nonwoven fabric for skin care products absorbs the excessive chemical solution between the nonwoven fabric for skin care products and the skin, whereby the contact area between the nonwoven fabric for skin care products and the skin is increased, and as a result, the adhesiveness and the wiping property at the time of wetting can be further improved. These thermoplastic resins may be polymerized with other components and may contain additives such as stabilizers.

Examples of the polyamide include nylon 6, nylon 11, nylon 12, nylon 66, and various aramid resins. Among these, nylon 6 having good water absorption can be preferably used.

In the group of thermoplastic resin fibers contained in the present invention, the thermoplastic resin fibers may be present as being separately dispersed, at least a part of the thermoplastic resin fibers may be present as being partially bonded to each other, or at least a part of the thermoplastic resin fibers may be present as being aggregated to form a fiber bundle. Further, the length, cross-sectional shape, and the like of the thermoplastic resin fibers are not particularly limited, and may be in a so-called fibrous form.

The nonwoven fabric for skin care products of the present invention contains cellulose fibers having a tensile strength of 1.9cN/dtex or less and an appropriate softness. The cellulose fibers are explained below.

The nonwoven fabric for skin care products in a wet state follows fine irregularities of the skin at a higher level. Further, as a result, the skin care product using the nonwoven fabric for skin care products is further excellent in adhesion and rub-off property, and for this reason, the tensile strength of the cellulose fiber is preferably 1.7cN/dtex or less, more preferably 1.5cN/dtex or less. The lower limit of the tensile strength of the cellulose fiber is not particularly limited, but is preferably 0.9cN/dtex or more because the skin care product can be more excellent in handling properties. The fiber length of the cellulose fiber is preferably 35mm or more. By setting the fiber length of the cellulose fiber to 35mm or more, the degree of entanglement of fibers in the nonwoven fabric for skin care products becomes large. Further, the degree of entanglement of the fibers in the nonwoven fabric for skin care products increases, and the strength of the nonwoven fabric for skin care products when wet increases, resulting in more excellent handling properties of the skin care products. The upper limit of the fiber length of the cellulose fiber is not particularly limited, but is preferably 80mm or less in order to obtain more excellent step-passing properties of the fiber in the production steps described later.

As the cellulose fiber used in the present invention, plant-based natural fibers such as pulp and cotton, regenerated fibers such as rayon and cupra fibers (cupra), and semi-synthetic fibers such as acetate and triacetate can be used. Among these, rayon is preferable because the skin care product can be made more excellent in adhesiveness and wiping-off property.

In the nonwoven fabric for skin care products of the present invention, the total content of the thermoplastic resin fibers and the cellulose fibers is 85 mass% or more based on the total mass of the nonwoven fabric for skin care products. It is presumed that when the total content is 85 mass% or more, the bulkiness of the nonwoven fabric for skin care products increases when wet, and the flexibility of the nonwoven fabric for skin care products improves, and as a result, the skin care products are excellent in adhesion and erasure. For the reasons described above, the total content is preferably 95% by mass or more, and more preferably 100% by mass.

In addition, in the non-woven fabric for skin care products of the present invention, the content mass ratio of the thermoplastic resin fibers to the cellulose fibers (thermoplastic resin fibers/cellulose fibers) is 0.06 to 0.22. When the content ratio is in the above range, the skin care product is excellent in adhesiveness and erasure property. Further, the handleability of the skin care product is further improved by increasing the content of the cellulose fibers based on the content of the thermoplastic resin fibers, and for the reason described above, the content mass ratio is preferably 0.20 or less.

Here, softness in the present invention means softness when the nonwoven fabric for skin care products of the present invention is compressed in the thickness direction of the nonwoven fabric for skin care products (i.e., softness when compressed). As a method for evaluating the flexibility, there is a WC value measured by a KES compression tester. The WC value is the amount of work (gf cm/cm) up to the maximum pressure at the time of compressing the cloth²) The higher the value, the more excellent the softness upon compression. In the present invention, the WC value obtained by the KES compression test is the WC value measured when wet, and for the reasons described above, the WC value of the nonwoven fabric for skin care products is preferably 0.40gf cm/cm²More preferably 0.50gf cm/cm²More preferably 0.60gf cm/cm²The above.

The nonwoven fabric for skin care products of the present invention may contain thermoplastic resin fibers having a single fiber diameter of more than 800nm, cellulose fibers having a wet tensile strength of more than 1.9cN/dtex, or fibers other than thermoplastic resin fibers or cellulose fibers, within a range not to inhibit the effect. Examples of the fibers other than the thermoplastic resin fibers and the cellulose fibers include animal-based natural fibers such as silk and wool. Further, for example, in the case where a polyethylene terephthalate fiber having a single fiber fineness of 1.6dtex or more (a single fiber diameter of 12.3 μm) is included as the thermoplastic resin fiber having a diameter of more than 800nm, the cross-sectional shape of the fiber is preferably a deformed cross-section, and more preferably a flat cross-section. It is presumed that, since the cross-sectional shape of the fibers is a deformed cross-section or a flat cross-section, the second moment of the fibers becomes smaller than that of the fibers having a circular cross-section, and as a result, the softness when wet (i.e., the softness when compressed) and the following ability of the nonwoven fabric for skin care products are improved.

The non-woven fabric for skin care products of the inventionThe weight per unit area of (A) is preferably 25g/m²～150g/m²The lower limit is more preferably 30g/m²Above, more preferably 40g/m²The above. On the other hand, the upper limit is more preferably 100g/m²Hereinafter, more preferably 70g/m²The following. By setting the unit area weight to 25g/m²As described above, the nonwoven fabric for skin care products is excellent in strength. On the other hand, the weight per unit area was set to 150g/m²The flexibility of the nonwoven fabric is improved. The weight per unit area of the nonwoven fabric for skin care products of the present invention can be determined in accordance with JIS L1913: 19986.2, respectively.

The nonwoven fabric for skin care products of the present invention comprises thermoplastic resin fibers having a single fiber diameter of 50nm to 800 nm. It is also presumed that the fine irregularities that the thermoplastic resin fibers have entered the skin surface increase the contact area between the skin and the nonwoven fabric for skin care products, increase the friction coefficient between the nonwoven fabric for skin care products and the skin, and suppress the nonwoven fabric for skin care products from slipping on the skin surface, which contributes to the improvement of the adhesiveness and the wiping-off property of the skin care products. Further, as a method for evaluating the friction coefficient between the nonwoven fabric for skin care products and the skin, the friction coefficient can be evaluated in accordance with JIS P8147: 19943.2 the inclined method was evaluated based on the coefficient of static friction when a nonwoven fabric for skin care products was impregnated with a cosmetic water. The reason why the adhesion or the rub-off property of the skin care product is more excellent is that the static friction coefficient between the nonwoven fabric for skin care products and the skin is preferably 0.5 or more, more preferably 0.6 or more.

Further, it is presumed that the nonwoven fabric for skin care products of the present invention contains cellulose fibers having a tensile strength of 1.9cN/dtex or less, and that the nonwoven fabric for skin care products has improved followability along fine irregularities of the skin when wet, and as a result, contributes to improvement of adhesiveness or wiping property of the skin care products. That is, when the 20% elongation stress of the nonwoven fabric for skin care products when wet is 5.0N/25mm or less, the following property is preferable because it is sufficient to improve the adhesiveness of the skin care product. For the reasons described above, it is more preferably 4.0N/25mm or less, and still more preferably 3.0N/25mm or less. The elongation stress of the nonwoven fabric for a skin care product when wet according to the present invention can be measured by the following method, based on JIS L1913: 19986.3.2, the stress at 20% of the initial elongation of the nonwoven fabric for skin care products was measured by a constant-speed elongation tensile tester. Further, for example, by appropriately adjusting the content of cellulose fibers in the nonwoven fabric for skin care products of the present invention, the single fiber fineness of the cellulose fibers, and the like, the 20% elongation stress of the nonwoven fabric for skin care products in a wet state can be made desirable.

The nonwoven fabric for skin care products of the present invention preferably contains 70 mass% or more of cellulose fibers having excellent liquid retention properties based on the total mass of the nonwoven fabric for skin care products. With this configuration, when the liquid medicine is impregnated in the nonwoven fabric for skin care products to form skin care products, the liquid medicine is taken into the fibers by the cellulose fibers, so that volatilization of the liquid medicine in the air can be suppressed, and the liquid retention of the skin care products can be improved. This is presumed to contribute to the improvement of the adhesiveness (particularly, adhesiveness after 20 minutes) or the scratch resistance of the skin care product. As a method for evaluating the liquid retention, a nonwoven fabric for a skin care product impregnated with a lotion was placed on a simulated skin, and the evaluation was performed by using the chemical solution retention ratio of the initial value of the quality of the lotion held by the nonwoven fabric for a skin care product and the value of the quality of the lotion held by the nonwoven fabric for a skin care product after 20 minutes. The liquid medicine retention rate of the nonwoven fabric for skin care products after 20 minutes is preferably 75% or more, more preferably 80% or more, and even more preferably 85% or more, from the viewpoint of adhesion or wiping property when kept wet for a long time.

Here, the nonwoven fabric for skin care products of the present invention is preferably a dry nonwoven fabric. By forming the dry nonwoven fabric, the thickness of the nonwoven fabric can be increased as compared with the wet nonwoven fabric, and as a result, the softness of the nonwoven fabric during compression can be improved. Further, the nonwoven fabric for skin care products of the present invention is preferably a spun-lace nonwoven fabric among dry nonwoven fabrics. The spunlace nonwoven fabric can be obtained by a method of intertwining constituent fibers with each other by a high-pressure water stream, and in this method, compared with a method of intertwining constituent fibers by needling, the method has less yarn breakage of the constituent fibers at the time of intertwining, and can obtain a soft touch nonwoven fabric for skin care products.

As a method for obtaining the thermoplastic resin fiber of the present invention, for example, a method disclosed in international publication No. 12/173116 can be used.

The nonwoven fabric for skin care products of the present invention can be used to produce skin care products such as facial masks, skin care sheets, eye masks, cleansing sheets, and cleansing sheets for spot make-up (spot make-up), by immersing the nonwoven fabric for skin care products in a cosmetic solution, a cleanser, or other liquid chemicals.