JP4687163B2 - Formulated solution, emulsion or gel and method for producing the same - Google Patents

Description

  The present invention is a solution containing ultrafine fibers (hereinafter referred to as nanofibers) having a fiber diameter on the order of nanometers (nm), which is useful in the fields of cosmetics, paints, medical fields, and electronic materials. The present invention relates to emulsions, gels, various products such as cosmetics and paints using these, and methods for producing the same.

  Recently, various functions of cosmetics have been proposed. For example, cosmetics that are easy to maintain healthy skin, have good adhesion to the skin, and are well washed off, and rough skin such as collagen, hyaluronic acid, squalane, urea and other aging and keratinization prevention, and allantoin Cosmetics that can be prevented, blackening and stains by UV absorbers such as benzophenone and zinc oxide, melanin production inhibitors such as arbutin and squalane, whitening cosmetics by activating skin cells, glycerin, hyaluronic acid, Cosmetics that can keep moist and fresh skin with moisturizers and wetting agents such as silicone and lanolin, cosmetics that can improve makeup with organic substances, cosmetics that can prevent dullness and dullness, transparency and color tone, etc. Cosmetics that can express the high-class feeling.

  In order to provide such functions, various oily components for protecting the skin, moisturizers, thickeners, whitening agents, UV inhibitors, fine particles, pigments, and the like are blended in water or a solvent. There are problems such as a method of uniformly dispersing various compounding agents and stabilizing an emulsification compounding. Further, the product is required to have good uniformity and dispersibility of the compounding agent in cosmetics and excellent long-term storage stability. Furthermore, it is required to have a cosmetic feel, a feeling of use at the time of makeup such as elongation and touch, and a makeup feeling against sweat after the makeup, etc., and easy removal of makeup.

  In conventional cosmetics, surfactants and natural dispersants are used, compounding agents are supported on base materials such as inorganic fine particles, organic fine particles, polymer gels, natural gels, collagen, and acrylamide polymers. By dispersing various compounding agents with a thickener or the like, studies have been made to improve the uniform dispersibility and stability of various compounding agents and solve the above-mentioned various problems of cosmetics.

  Recently, in cosmetics, when an oil component is dispersed as a compounding agent (for example, Patent Documents 1, 2, and 3), an oil component micro-dispersion technique for reducing the particle size of the oil component fine particles to 1 μm or less has been studied. In addition, when the compounding agent is inorganic fine particles, a technique for compounding fine particles having a diameter of 0.1 μm or less (hereinafter referred to as nano fine particles) has been studied. (For example, Patent Documents 4, 5, 6, 7, and 8) The uniform dispersion of such oil component fine particles and solid component fine particles can be achieved by selecting the type of lipid or controlling the surface tension by optimizing the surfactant. This conventional method can be improved to some extent. However, its long-term storage stability is more difficult as the diameter of the fine particles becomes smaller, especially when it becomes a nano fine particle, it is very easy to agglomerate, and instead of being dispersed, it forms a secondary agglomerated particle and precipitates. A problem has arisen that the original purpose of achieving uniform dispersion of the nanoparticles is not achieved.

  Use of glycerins (for example, Patent Documents 9 and 10) and use of acrylamides (for example, Patent Documents 11 and 12) in order to improve the uniform dispersibility of compounding agents and fine particles and to stabilize the dispersion state for a long period of time. However, the dispersibility and long-term stability of these dispersants themselves may not be sufficient. For example, an oil-in-water emulsion having an acrylamide diameter of 50 to 1000 nm (for example, Patent Document 13) is disclosed. Such dispersants are finely divided to provide good elongation when applied to the skin and excellent touch, but they have a sticky feeling due to the properties of acrylamide itself, and are refreshing and refreshing when using cosmetics. There was the fault that a feeling of feeling and a natural feeling were spoiled.

  For this reason, uniform dispersibility of compounding agents and fine particles, long-term storage stability, good adhesion to the skin, smooth and good stretch, excellent touch, no stickiness when used, and cosmetic use Materials that are superior in the refreshing, refreshing, and natural feelings of time have been demanded.

  Conventionally, a method for adhering and dispersing a compounding agent using a clay material such as talc or bentonite or inorganic particles as a carrier as a material has been proposed, but the particle size of the carrier is as large as several μm or more. In addition to being difficult to uniformly disperse in cosmetics, the particle size of the carrier is large, so that there is a rough feeling when using cosmetics, and there is a problem that freshness and natural feeling are impaired.

  As another method, cosmetics containing natural fibers such as collagen fibers have recently been studied as a compounding agent different from the organic fine particles and inorganic fine particles (for example, Patent Documents 14, 15, and 16). These are materials that can be easily modified to penetrate or absorb the skin by reducing the molecular weight of collagen or by chemically modifying collagen fibers. The action as a form and function was small. Moreover, although the examination example (for example, patent document 17) which refined | miniaturized the silk fibroin fiber is also disclosed, although fiber length becomes a short fiber of 1-200 micrometers, a fiber diameter is about 10 micrometers and is called a fine fiber. Since it should be a silk powder of 10 μm or more than the above, it is large when viewed as a particle, the dispersibility of the silk powder itself is poor, it is easy to settle, and it is a material that supports and disperses other nanoparticles. The required properties were insufficient. As another method, there is an example in which cellulose fibers are used (for example, Patent Document 18). When such cellulose fibrils are used, the variation in diameter of cellulose fibril fibers is as large as 1/10 to 1/100. It is very difficult to uniformly disperse the large and small diameters, and it is very difficult to disperse them uniformly. Also, the large ones tend to settle and settle together rather than disperse the fine particles. There was also a drawback. In addition, there are defects such as generation of mold during storage and lack of flexibility due to the high rigidity of the fiber itself.

  Furthermore, there is an example using nanofibers made of cellulose (Patent Document 19). However, since the fibers are too thin, the absolute strength of the fibers is low, and the cellulose fibers are broken and shattered when dispersed. Because of cellulose, there is a problem that mold is generated during storage of the dispersion. From this viewpoint, it has been demanded to use ultrafine fibers made of a synthetic polymer, not cellulose.

  Therefore, regarding the use of ultrafine fibers made of a synthetic polymer, “cosmetics blended with ultrafine fibers” for the purpose of obtaining velvet-like luster and natural luster of infant's hairy tone (for example, Patent Document 20) ) Is disclosed. Although the fiber length of the ultrafine fiber used here is as short as 50 μm or less, the fiber diameter is 2 μm (0.055 dtex). When blended in cosmetics, the fiber diameter is still thick except for special makeup applications. In addition, the flexibility was insufficient, the skin was unsuitable, the feeling of use was uncomfortable, and the dispersibility of the fiber itself in water and oil and the familiarity with fine particles were insufficient. For this reason, even if it is used as ultrafine fibers in woven fabrics, knitted fabrics, non-woven fabrics, etc., it has been difficult to apply in the cosmetics field due to the lack of thinness and flexibility.

  Here, between the fineness (dtex) of the fibers usually used in the fibers described in the patent documents cited above and the number average diameter φ (μm) of the single fibers used in the synthetic paper of the present invention The following equation (1) is established.

φ = 10 × (4 × dtex / πρ) ^1/2 (1)
Here, dtex refers to the fiber thickness (JIS L 0101) (1978) that makes the fiber 1 g in weight of 10,000 m.

  For example, when the fineness is converted into the average number of single fibers referred to in the present invention, for example, when the polymer is nylon, the specific gravity is a value converted by 1.14 (equivalent to nylon 6).

φ _n6 = 10.6 × (dtex) ^1/2
In addition, when the type of polymer is different from nylon 6, the calculation may be performed by replacing the specific gravity of the polymer in the above formula.
JP 10-147506 A JP 2001-214081 A JP 2001-261526 A JP 05-186323 A JP 2000-264632 A JP 07-002639 A JP 2001-089314 A Japanese Patent Laid-Open No. 2003-300844 Japanese Patent Application Laid-Open No. 07-185294 JP 2000-128760 A Japanese Patent Laid-Open No. 06-21626 JP-A-10-066765 Japanese Patent Laid-Open No. 10-087428 JP 55-28947 A JP-A-63-215770 JP 08-27192 A Japanese Patent Laid-Open No. 11-100510 JP-A-62-39507 Japanese Patent Laid-Open No. 13-2523 JP 2001-64153 A

  An object of the present invention is to provide a blended solution, an emulsion, and a gel-like product that are excellent in uniform dispersibility and long-term stability of dispersion, and have excellent properties as a cosmetic.

In order to solve the above problems, the present invention has the following configuration.
(1) Polyester, polyamide, polyolefin, polyphenylene sulfide, phenol resin, polyvinyl alcohol, polysulfone, polyurethane, a fluoropolymer, and a thermoplastic polymer that is at least one selected from the group consisting of derivatives thereof. A blended solution comprising a fiber dispersion having a single fiber diameter of 1 to 500 nm, a sum Pa of the single fiber ratio of 60% or more, and a solvent.
( 2 ) Cosmetics using the said mixing | blending solution.
( 3 ) A coating material using the above blended solution.
( 4 ) The method for producing the blended solution, wherein the fiber assembly is directly beaten in at least one selected from the group consisting of water, oil and organic solvent.

  According to the present invention, in recent cosmetics, medical products, and other fields, nanofibers are blended into compounding solutions, emulsions, and gels, thereby forming microparticles composed of noble metals, metal oxides, and polymer fine particles of 1 μm or less. Not only can fine particles and nano fine particles be uniformly dispersed, but also the dispersion can be stabilized over a long period of time.

  In addition, when conventional fibers having a diameter of several μm or more were blended into cosmetics, there was a feeling of roughness, and it did not become a practical compounding agent. However, the nanofiber of the present invention is thinner than the wrinkles on the skin surface, and is suitable for the skin. Familiarity is good, and a soft and natural feel can be obtained on the skin. By blending the nanofibers, the slipperiness, water retention, moisture retention, elongation, and packability of the cosmetics are good, the makeup is improved, and functions not found in conventional fibers can be obtained. Therefore, taking advantage of the features such as the fineness and specific surface area of nanofiber, lotion, lotion, liquid foundation, shampoo, rinse, emulsion, cold cream, cleansing cream, shaving cream, hair cream, gel for packs and ointments, The nanofiber of the present invention can be blended with hair styling gel, face washing gel, soap gel, pack material, etc., and applied to many types of cosmetics.

  Furthermore, the effects such as dispersibility, uniformity, and storage stability of nanofibers are not limited to cosmetics, but include medical fields such as ointments, poultice liquids, cell culture substrates, protein adsorbents, battery electrolyte materials, Materials for fuel cell catalyst carriers, materials for catalyst carriers for chemical filters, adsorbents for harmful gases, and other electronic substrates and devices related to electronic devices, paints, adhesives and wall materials containing various fillers and pigments It is also effective in the field of building materials such as coating materials for coatings, in the field of industrial materials such as purification filters, activated carbon for purification filters and particulate carriers such as titanium oxide, and paints for painting.

  Also, in fields that are difficult to deal with conventional ordinary synthetic fibers and ultrafine fibers, the compound solution, emulsion, and gel-like product of the present invention can absorb various substances (eg, fine particles, chemical substances, proteins, pathogenic bacteria, etc.) Surface activity at the nanometer level, such as absorption, ecological compatibility and compatibility, and chemical interaction of the surface are expected.

  Hereinafter, the present invention will be described in more detail.

  Examples of the thermoplastic polymer constituting the nanofiber dispersion of the present invention include polyester, polyamide, polyolefin, and polyphenylene sulfide (PPS). Examples of the polyester include polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), and polylactic acid (PLA). Examples of polyamide include nylon 6 (N6), nylon 66 (N66), nylon 11 (N11), and the like. Examples of the polyolefin include polyethylene (PE), polypropylene (PP), and polystyrene (PS). In addition to the thermoplastic polymers described above, it is of course possible to use phenol resins, polyacrylonitrile (PAN), polyvinyl alcohol (PVA), polysulfone, fluorine-based polymers, and derivatives thereof.

  Among these polymers, those having a melting point of 165 ° C. or higher are preferable from the viewpoint of heat resistance. More preferably, a polycondensation polymer represented by polyester or polyamide has a high melting point, for example, PP is 165 ° C, PLA is 170 ° C, N6 is 220 ° C, and PET is 255 ° C. These polymers may contain compounding agents such as fine particles, flame retardants and antistatic agents. Further, other components may be copolymerized as long as the properties of the polymer are not impaired. Furthermore, a polymer having a melting point of 300 ° C. or lower is preferable because of ease of melt spinning.

  In particular, polyamides represented by N6 and N66 are excellent in water absorption and water retention. Taking advantage of these properties, the nanofibers of PA are blended into the blended solution and emulsion of the present invention and the gel-like product for cosmetic use. It can use suitably for.

  The fiber dispersion used in the present invention refers to a nanofiber having a number average single fiber diameter (single fiber number average diameter) in the range of 1 to 500 nm, and its form is a dispersion of single fibers. It is. Moreover, what is necessary is just a fibrous form, and it does not stick to the length or cross-sectional shape. In the present invention, the average value and variation of the single fiber diameters of the nanofibers are important. In order to disperse nanofibers uniformly in compounded solutions, emulsions, and gels, and to improve long-term storage stability so that nanofibers do not aggregate or settle over time, the average number of single fibers is 1 to 500 nm. It is important that it is 1 to 200 nm, more preferably 1 to 150 nm, and even more preferably 1 to 100 nm.

  Here, the single fiber number average diameter is evaluated by the measurement methods “H. SEM observation of nanofibers” and “I. Nanofiber single fiber average diameter φm” in the examples described later, and variations in single fiber diameters. Are represented by “H. SEM observation of nanofiber”, “J. Evaluation of sum Pa of nanofiber single fiber ratio” and “K. Evaluation of concentration index Pb of single fiber diameter of nanofiber”.

  The average number of single fibers is the same as that obtained by sampling nanofibers from mixed solutions, emulsions, and gels, and observing the surface of the sampled nanofibers with a transmission electron microscope (TEM) or scanning electron microscope (SEM). The diameter of 30 single fibers randomly sampled on the surface is measured, and further sampling is performed 10 times, and the simple average value is obtained from the data of the total diameter of 300 single fibers. In the present invention, it is called “φm”. Moreover, the dispersion | variation in the single fiber diameter of nanofiber is evaluated as follows. In order to create a distribution table (histogram) from the single fiber diameter obtained above, the single fiber diameter φ is divided into arbitrary sections (n), and the average value at both ends of each section is defined as φi. The frequency fi for the diameter section φi (i = 1 to n) of each nanofiber of the section is counted, and a distribution table is created. As a method of dividing into arbitrary sections, for example, when the single fiber number average diameter φm is 500 nm or less, one section may be 1 to 10 nm and n may be 10 to 100 sections. (For comparison, when the single fiber number average diameter φm exceeds 500 nm, one section may be 1/10 or less of the number average diameter φm, and n may be 10 to 100 sections).

  Next, “sum of single fiber ratio Pa” and “concentration index Pb” for evaluating the variation in single fiber diameter will be described.

  The frequency fi of nanofibers having a single fiber diameter φi entering the same section is counted, and the ratio of the single fiber diameter divided by N is defined as Pi. Pa can be obtained by simply adding individual fi / N up to a partition number r in the range of 1 to 500 nm.

N = Σfi (i = 1 to n) (2)
Pa = Σ (fi / N) (i = 1 to r) (3)
Specifically, the individual fi / Ns up to the partition number r within the range of 1 to 500 nm may be added. In the present invention, it is important that the nanofiber has Pa of 60% or more, preferably 65% or more, and more preferably 70% or more. As Pa is larger, the number ratio of nanofibers referred to in the present invention is larger, and the number of coarse single fiber diameters is smaller. Thereby, the function of the nanofiber can be sufficiently exhibited, and the quality stability of the product can be improved.

  Moreover, the concentration index Pb of the single fiber diameter indicates the concentration in the vicinity of the average diameter of the single fibers. Using the frequency fi of φi obtained as described above, based on this data, “a distribution table (histogram) of the frequency fj for the section of the square value χi of the single fiber diameter φi is prepared. A table of values Pj obtained by integrating the frequencies fj is prepared in advance.

Pj = Σ (fj / N) (j = 1 to n) (4)
Since the square value χ i of the single fiber diameter φ i is proportional to the weight of the fiber (cylindrical shape), it corresponds to the dtex, that is, the distribution with respect to the fineness, as can be seen from the equation (1). An approximate function Q (4 to 6th order function of χi) of “accumulated frequency number Pj” with respect to χi is created by Excel (trade name) manufactured by Microsoft Corporation. Then, assuming that the average number of single fibers φm is the median, the square value of 15 nm plus φm is χa, and the squared value of φm minus 15 nm is χb, the concentration index Pb can be obtained from the following equation: .

Pb = Q (χa) −Q (χb) (5)
In the present invention, the nanofibers preferably have a single fiber diameter concentration index Pb representing the ratio of fibers entering 30 nm before and after the number average single fiber diameter as a median value of 50% or more, and 60% or more. More preferably, it is more preferably 70% or more. This means that the higher the Pb, the smaller the variation in the single fiber diameter. The actual measurement methods of the actual single fiber number average diameter φm, the single fiber ratio sum Pa, and the single fiber diameter concentration index Pb are shown in the examples described later.

In the present invention, the nanofiber dispersion can be used to obtain a compound solution, an emulsion, or a gel. This can be achieved for the first time by the nanofiber. For example, nanofibers obtained by the electrospinning method usually collect nanofibers only in the form of nonwoven fabric, so there is no idea of uniformly dispersing the obtained nanofibers in a solvent, and it is difficult to do this In fact, there was no example in which nanofibers were dispersed in a solvent. On the other hand, in the present invention, a polymer alloy fiber is obtained by a highly productive melt spinning method, from which sea components are removed to form a nanofiber aggregate, which is further shortened to be beaten and dispersed. In order to obtain a nanofiber dispersion, it has become possible for the first time to efficiently produce the above-described blended solution, emulsion, and gel.
The nanofiber compound solution, emulsion, and gel-like material of the present invention are composed of a nanofiber dispersion and a solvent or gel. The blended solution, emulsion, and gel-like product of the present invention refer to a liquid or solid product in which nanofibers or nanofibers and other drugs are blended in a solvent or gel.

The compounding solution referred to in the present invention is a solution in which a nanofiber dispersion is dispersed in a solvent at a relatively low concentration, and has a relatively low viscosity and high fluidity. In addition, a nanofiber dispersion having a relatively high concentration in a solvent or gel and having a relatively high viscosity and low fluidity is defined as a gel-like material. In addition, an emulsion is defined as a compounded solution forming an emulsion in which a nanofiber dispersion is dispersed in the emulsion at a relatively low concentration.
Here, the solvent or gel not only dissolves the compounding components other than the nanofibers in the compounding solution, the emulsion, and the gel-like material, but also acts as a dispersion medium for the nanofibers.

  Moreover, a solvent can be used in combination as appropriate among water and / or oil and / or organic solvent (including emulsion). Oils include linseed oil, corn oil, olive oil, sunflower oil, rapeseed oil, sesame oil, soybean oil, cacao oil, palm oil, palm oil, owl, and other natural oils, paraffin, petrolatum, ceresin, liquid paraffin, squalane, wax, There are higher fatty acids, silicone oils, cross-linked silicone oils, etc., which can be used alone or in combination of two or more. Organic solvents include alcohols, esters, glycols, glycerols, ketones, ethers, amines, lower fatty acids such as lactic acid and butyric acid, pyridine, tetrahydrofuran, furfuryl alcohol, acetonitriles, methyl lactate , Ethyl lactate, etc., which can be used alone or in combination of two or more.

  The nanofiber dispersion having a single fiber diameter of 1 to 500 nm used in the present invention preferably has a freeness of 350 or less from the viewpoint of improving dispersibility in a solvent. The freeness is more preferably 200 or less, and still more preferably 100 or less. The lower limit of the freeness is preferably 5 or more.

  Next, a nanofiber having a single fiber diameter of 1 to 500 nm used in the present invention is compared with a conventional synthetic fiber. Two types of conventional fibers, a fiber having a diameter of 10 μm or more (hereinafter referred to as a normal fiber) and a fiber having a diameter of more than 0.5 μm (500 nm) and a diameter of 10 μm or less (hereinafter referred to as an ultrafine fiber). Examples of typical fiber diameters of the fibers are shown in Table 1 for the fibers (nanofibers A and B) used in the present invention having a diameter of 0.5 μm (500 nm) or less.

  The above-described equation (1) is established between the fineness (dtex) of the fiber that is usually used frequently and the diameter φ (μm) of the single fiber.

φ = 10 × (4 × dtex / πρ) ^1/2 (1)
Here, dtex is the thickness of a fiber (JIS L 0101) having a length of 10,000 m and a weight of 1 g.

  When the specific gravity is converted to 1.14 (equivalent to nylon 6), the diameter φ (μm) of the single fiber is obtained by the following equation.

φ _n6 = 10.6 × (dtex) ^1/2
Conventional fibers and ultrafine fibers (hereinafter collectively referred to as conventional fibers) as conventional fibers, and nanofiber A having a diameter of 200 nm and nanofiber B having a diameter of 60 nm are used as fibers having a diameter of 1 to 500 nm used in the present invention. It was shown in 1. The fiber diameter here is the single fiber number average diameter φm defined by the above formula (1), and a transmission electron microscope (TEM) or a scanning electron microscope (TEM) as shown in the measurement method in the examples described later. SEM).

  Table 1 shows a comparison of the number of fibers contained per 1 ml of a 0.01 wt% aqueous solution or lotion and the specific surface area of the fibers cut into 2 mm. Compared to the conventional fibers of 160 fibers for normal fibers and 16,000 fibers for ultrafine fibers, the number of nanofibers A is 1.6 million, and the finer nanofibers B are 18 million, and the number is extremely high. The aspect ratio is also increased.

  Taking advantage of features such as fine fiber diameter and large specific surface area, various cosmetics can be obtained as follows by using the nanofiber compound solution, emulsion, and gel-like material of the present invention alone or in combination. . Specific examples of cosmetics include lotions (eg, general lotion, cologne, after shaving lotion, sunscreen lotion, etc.), cream emulsions (eg, general lotion, after shaving cream, cleansing cream, cold cream). , Shaving cream, hand cream, sunscreen, etc.), foundations (eg, liquid foundation, cream foundation, solid foundation, etc.), fungi (eg: creamy, solid, powdery, baby powder, body powder Etc.), cosmetics for hair (eg hair oil, set lotion, tics, hair cream, hair nick, hair liquid, hair spray, pomade etc.) and detergent cosmetics (eg shampoo, phosphorus) , Cosmetic soaps, makeup removers, etc.), lipsticks (eg, lipstick, lip balm, etc.), packs, eyebrow cheek cosmetics (eg, eye shadow, eyeliner, eye cream, blusher, mascara, eyebrow, etc.) , Nail enamels, toothpastes, ointment gels, and the like, and nanofiber-containing solutions, emulsions, and gels can be combined or used properly according to the purpose and purpose.

  By the way, even if various dispersing agents are added to skin lotions and emulsions containing an oil component having a dispersion diameter of a micron level, nano-level noble metals of several nanometers to several hundred nanometers or ultrafine particles of other compounding agents, etc. It was very easy to aggregate and it was difficult to make the dispersion of ultrafine particles uniform. Moreover, even if dispersed uniformly, when stored for a long period of time, the uniformity of dispersion is reduced, and separation and sedimentation may occur due to aggregation. Once separated, it was difficult to return to a state where fine particles were dispersed as in the initial stage even if the contents were stirred by shaking the bottle well. Since this phenomenon occurs not only in the formulation solution but also in the emulsion or gel state, in the cosmetics field, it has been required to stabilize the dispersion so that the fine particles can be uniformly dispersed and stored for a long period of time.

  In this respect, the above-mentioned problems can be solved by using the nanofiber compound solution, emulsion, or gel-like material of the present invention. In the nanofiber compound solution of the present invention, as shown in Table 1, the nanofiber contains 18 million fibers per 1 ml of the solution, and the specific surface area becomes very large. Further, in the case of nanofibers, when the cut length of the fiber is 2 mm, the ratio of fiber length (L) / fiber diameter (D) as shown in Table 1, that is, the aspect ratio is 10,000 to 33000, which is a very long fiber. . For this reason, when nanofibers are added to a compound solution, emulsion, or gel, the above-described micron-level microparticles or nanoparticle can be uniformly supported on the nanofiber surface. This makes it possible to disperse various blended fine particles such as noble metal fine particles having a large specific gravity and an ultraviolet shielding agent without using the nanofibers, and to prevent the fine particles from aggregating. In addition, the fine and long nanofibers move against fine particles that have started to lightly agglomerate and become flocs or clusters in the solution. Can also be done.

  In addition, there are 18 million thin and long nanofibers per ml of solution, and the nanofibers are dispersed in the solution, which means that the space in the compounded solution, emulsion, and gel is very large. The nanofibers are spread finely and the fine particles supported on the surface are also uniformly dispersed. In addition, the dispersed nanofibers have entanglement and adhesion between the fibers, and a network-like space of nanofibers is formed. Since this network state is very stable over the long term, it is stable for a long time without agglomeration or precipitation of liquid ultrafine particles such as oil droplets and emulsions, and various compounded particles such as precious metal fine particles with a high specific gravity and UV screening agents. It can be stored.

  In addition, it is very effective to blend nanofibers in order to stabilize dispersion of an emulsion or fine particle compounding agent, which is difficult to stabilize only by ordinary dispersing agents and pH adjustment. In the case of the nanofiber compounded solution, emulsion, and gel-like product of the present invention, the concentration of nanofibers incorporated in each is preferably 30 wt% or less in the case of a gel-like product, and exceeds 1 wt% and 5 wt% or less. It is more preferable that Moreover, in the case of a compounded solution and an emulsion, it is preferable that it is 5 wt% or less, More preferably, they are 0.0001-1 wt% and 0.003-0.3 wt%. As shown in Table 1, in the case of nanofibers having a diameter of 60 nm (0.06 μm) even at 0.01 wt%, as many as 18 million fibers are contained. It is effective for storage stabilization. Of course, it is possible to adjust the content of nanofibers in consideration of the type, concentration, storage period, influence of other compounding agents, and the like.

  The nanofiber having a single fiber average diameter of 1 to 500 nm used in the present invention is preferably a short fiber having a fiber length of 20 mm or less. When the fiber length exceeds 20 mm, the nanofibers tend to be entangled with each other excessively, so that dispersibility may be lowered. For this reason, in order to disperse nanofibers well in a nanofiber compound solution, emulsion, or gel, the length of the nanofibers is preferably 0.05 to 2 mm, and further applied to gels. In some cases, the length of the nanofiber is preferably 0.2 to 1 mm, and when applied to an emulsion, the length of the nanofiber is preferably 0.05 to 0.8 mm. In particular, it is preferable to add a small amount of oil or a gel-like material because nanofiber aggregation is likely to occur. In the case of a gel-like material, it is also preferable to mix with a mixer having a strong shearing force such as a kneader or a twin-screw mixer.

  Moreover, it is preferable that ratio (L / D) of fiber length L (mm) and number average fiber diameter D (mm) is 100-50000 in the nanofiber of this invention. By making L / D within this range, the dispersibility of the nanofibers in the blended solution, emulsion, and gel-like material of the present invention can be improved. L / D is more preferably 1000 to 20000, and even more preferably 500 to 2000.

  In the present invention, the blended solution added with nanofibers in particular has good transparency. The transparency is evaluated according to the “P. Transparency” measurement method in Examples described later. For example, as in Example 6, the nanofiber compound solution having a nanofiber length of 2 mm and a nanofiber concentration of 0.01 wt% has a translucency of 51% and has excellent transparency. In this case, the fiber diameter of the nanofiber is 60 nm, which is smaller than the wavelength of light (400 to 700 nm), but the fiber length is very large, 2 mm (2000000 nm). Further, as shown in Table 1, the transparency is very good despite the fact that the number of nanofibers present in 1 ml of solution is as large as 18 million. This is considered to be an effect that the nanofibers are uniformly dispersed at the single fiber level. In order to further improve the translucency, the fiber concentration with respect to the solution is preferably 0.0001 to 0.01 wt%, and the fiber length is also preferably shortened to 0.05 to 0.8 mm. More preferably, the thickness is 0.05 to 0.2 mm. If the concentration of the nanofiber is too low or the fiber length is too short, the stabilization effect due to the dispersion of the nanofiber is reduced. In order to improve the transmissivity, it is also effective to use an appropriate dispersant. When 0.1 wt% of an anionic dispersant is added to the mixed solution of N6 nanofibers, the transmissivity is reduced to 63%. Improved (Example 9 described later). Also, nanofibers are theoretically transparent in the diameter direction because the fiber diameter is smaller than the light wavelength, but the fiber length is much longer than the light wavelength, such as fiber overlap, pseudo-adhesion, cluster, flock state, etc. Transparency is considerably hindered by the influence, and irregular reflection tends to occur. In order to prevent irregular reflection and improve transparency, it is also preferable to coat or wet the surface of the nanofiber with a silicone-based, fluorine-based, urethane-based or acrylic acid-based polymer that adjusts the refractive index.

  The polymer constituting the nanofiber is selected depending on the application and purpose of use, but in cosmetics and medical applications, polymers that do not irritate the skin and the human body are preferred, particularly polyamides, polyolefins, polyesters. , Fluoropolymer, polyvinyl alcohol (PVA) or derivatives thereof are preferred. For cosmetic purposes, polyamide, polylactic acid, PVA or derivatives thereof are preferred from the viewpoint of providing moisture retention and water retention. Polyolefins, fluorine-based polymers or their derivatives with good chemical resistance are preferred for battery separators and industrial filters, and polyurethane, polyester, polyamide or their derivatives for building applications such as paints, wall materials and coating agents. Is preferred. Also, two or more kinds of polymers can be appropriately selected depending on the application and intended use.

  Next, the flexibility and feel of the nanofiber will be described.

  Flexibility can be evaluated by the amount of deflection of the material. The softer the amount of deflection, the larger the amount of deflection, and it is estimated by the following equation (6) of bending of the material in the Mechanical Engineering Handbook (p. In this equation, v is the amount of deflection, and increases in inverse proportion to the fourth power of the diameter D ((w: load, E: elastic modulus of the material).

v = 4 × w × l ³ / (3 × E × D ⁴ ) (6)
Compared with the conventional fiber, the softness of the nanofiber becomes softer in inverse proportion to its fourth power by reducing the fiber diameter. For example, the diameter of an ultrafine fiber is 1/10 of that of a normal fiber, and v is 10,000 times larger, so the flexibility of the ultrafine fiber is softer than 10,000 times that of a normal fiber. Nanofibers are 1/10 to 1 / 100th the diameter of ultrafine fibers, and the softness of nanofibers is 10,000 to 100 million times that of ultrafine fibers. For example, since the number of fibers taken out from an aqueous solution actually increases as the fibers become thinner, the fibers tend to become intertwined or form a network. Although it is not as estimated by calculation as in the equation, the flexibility of the fiber is greatly improved every time the diameter becomes 1/10.

  When fibers are dispersed in cosmetics and applied to the skin, normal fibers are not suitable because they are stiff and difficult to bend, so that the skin is stimulated or rough even when applied. In the case of the ultrafine fiber, the flexibility is improved as compared with the case of the normal fiber, but the feeling of strangeness is still strong at the time of application and after application. The cause is considered as follows. That is, the groove width of the skin wrinkle is 1 to several tens of μm, and the diameter of a normal ultrafine fiber is several μm. Therefore, it is theoretically possible to enter the wrinkle, but the fibers actually aggregate. It is estimated that the fiber is in a state of floating on the surface of the skin because it is large or cannot be deformed along the wrinkles because the fiber has high rigidity.

  On the other hand, the fiber diameter of the nanofiber is 0.5 μm (500 nm) or less, which is overwhelmingly narrower than the groove width of the wrinkle, and the flexibility of the fiber is remarkably superior. Furthermore, since nanofibers are flexible, there is little irritation to the skin, and it is thought that they feel smooth and moist. In addition, since nanofibers have a large specific surface area and are excellent in water retention and moisture retention, when water is contained in nanofibers, the effect is further improved and the familiarity with the skin becomes very good. For example, with simple water to which nanofibers have been added (skin lotion or milky lotion), the face becomes smooth just by washing the face, but there is almost no sense of incongruity during use (Examples 10 to 10 described later). 16). However, the conventional normal fiber lotion having a diameter of several tens of μm has a rough feeling during use, and the use feeling is very bad (see Comparative Examples 7 and 8 described later). In addition, even with the conventional ultrafine fiber having a diameter of 2 μm, the fiber is only on the skin as described above, the touch is bad, and the flexibility is very hard compared to the nanofiber, I felt uncomfortable.

  Next, the moisture retention and water retention of the nanofiber will be described.

  Nanofibers are excellent in moisture retention and water retention because their specific surface area is very large compared to conventional fibers. Moisturizing properties can be evaluated from the weight loss of fibers by putting a certain amount of fiber in a box conditioned at low humidity, but the higher the weight reduction rate (drying rate), the worse the moisture retention. Yes. The actual measurement method is evaluated by the evaluation method “M. Moisturizing index (ΔWR10)” in the column of Examples described later. As a result of comparing the conventional fiber with the nanofiber of the present invention, the moisture retention index is 39% / 10 min for the conventional normal fiber (Comparative Example 1 described later), and 29% / 10 min for the conventional ultrafine fiber (Comparative Example described later). In contrast to 3), the amount of nanofibers was as small as 13% / 10 min (Example 1 described later). Thus, it was found that the moisture retention of the nanofibers is about 2-3 times or more that of conventional fibers. The water retention is the water content of the fiber when the fiber is sufficiently squeezed and then squeezed lightly. In order to make the squeeze method constant, the dewatering conditions of the centrifuge are made constant. An actual measurement method is evaluated by an evaluation method “N. Water retention index (WI)” in Examples described later. As a result of comparing the conventional fiber and the nanofiber of the present invention, the water retention of each fiber is 235% for the conventional normal fiber (Comparative Example 1 described later) and 509% for the conventional ultrafine fiber (Comparative Example 3 described later). On the other hand, the nanofiber was 1608% (Example 1 described later), and the nanofiber was found to have a very large water retention of 3 times or more compared to the conventional fiber. In addition, the moisturizing duration contributes to both the initial water retention amount (water retention) and the difficulty of drying (moisturizing property), but nanofibers are superior to conventional fibers in both performances. It is also superior in terms of moisturizing duration, and is effective not only for the direct moisturizing effect of cosmetics, but also for the prevention of dryness and sustained release effect of other moisturizing components, solvent components and aromatic components used in place of moisture. is there. Furthermore, in order to improve the moisturizing and water retaining effects, it is preferable that the concentration of fibers in the solution is slightly increased to 0.01 to 1 wt%. The fiber diameter is also preferably 120 nm or less, and more preferably 80 nm or less. In addition, the use in combination with other natural moisturizing and water-retaining agents and organic or inorganic moisturizing and water-retaining agents is also preferred.

  In addition to the above, as an application of a moisturizing agent and a water retaining agent using nanofibers, there is a cosmetic pack using a gel-like material containing nanofibers. This is because the nanofiber is mainly blended with other cosmetic compounding agents to form a gel-like product, which is supported on the pack base material, and the normal cosmetic pack base material itself is mixed with the nanofiber to form a pack. The method of doing is mentioned. Nanofibers are used for the purpose of moisturizing and water retention, but since the nanofibers are in fiber shape, they not only have good moisturizing and water retention, but also have good adhesion to the skin, so that the fibers can be used for thin wrinkles. Because it penetrates without a sense of incongruity, it has the effect of effectively penetrating the active ingredient for the pack. In addition, if other active ingredients such as milky lotion and cosmetics, such as moisturizing agents, whitening agents, anti-aging agents, and fragrances, are blended, the retention of these components is good and the use effect of the pack is increased. .

  As described above, the compound solution, emulsion, and gel-like product in which the nanofibers of the present invention are dispersed have been described mainly for use in cosmetics, but the dispersibility, uniformity, and stability in storage state of the fiber are In addition to cosmetics, medical fields such as ointments, poultice liquids, cell substrates, protein adsorbents, electrolyte materials for batteries, their carriers, catalyst carriers for fuel cells, and catalysts for chemical filters Electronic substrates such as carrier materials and harmful gas adsorbents and electronic equipment, paints to which various fillers and face amounts are added, building materials such as adhesives and coating materials for walls, purification filters and purification It can also be used in the field of industrial materials such as fine particle carriers such as activated carbon and titanium oxide for filters, and other paints for painting.

  Next, the manufacturing method of the nanofiber used for the compounding solution of this invention, an emulsion, and a gelled material is demonstrated.

  First, a method for producing “polymer alloy fiber”, which is a raw material for producing nanofibers, will be described. For example, the following method can be adopted as a method for producing the polymer alloy fiber.

  That is, two or more types of polymers having different solubility in solvents and chemicals are kneaded to prepare a polymer alloy chip, which is put into a hopper 1 of a spinning device (see FIG. 1), and polymer is melted in a melting part 2. The alloy melt is melted and discharged and spun from a nozzle hole 5 disposed in a spinning pack 4 in a heat-insulating spin block 3, and then cooled and solidified by a chimney 6 to form a yarn 7. A converged oiling guide 8, a first take-up roller 9. The fiber is wound up by the winder 11 through the second take-up roller 10. And this is extended | stretched and heat-processed as needed and a polymer alloy fiber is obtained. Further, this is treated with a solvent or a chemical solution to remove sea components, and nanofibers used in the present invention are obtained. Here, in a polymer alloy fiber, a polymer that is hardly soluble in a solvent or chemical solution that later becomes a nanofiber is used as an island component, and an easily soluble polymer is used as a sea component, and by controlling the size of this island component, In addition, it is possible to design the number average diameter and variation of single fibers of nanofibers.

  Here, the size of the island component is obtained by observing the cross section of the polymer alloy fiber with a transmission electron microscope (TEM) or a scanning electron microscope (SEM), and evaluating it in terms of diameter. The evaluation method of the number average diameter of the single fiber of the island component in the polymer alloy fiber is shown in the items F and G of the measuring method in the examples described later. Since the diameter of the nanofiber is almost determined by the island component size in the polymer alloy fiber that is the nanofiber precursor, the distribution of the island component size is designed according to the diameter distribution of the nanofiber. For this reason, kneading of the polymer to be alloyed is very important, and in the present invention, high kneading is preferably performed by a kneading extruder, a stationary kneader, or the like. It should be noted that simple chip blending (for example, Japanese Patent Application Laid-Open No. Hei 6-272114) is insufficient in kneading, so that it is difficult to disperse island components with a size of several tens of nm.

  Specific guidelines for kneading depend on the polymer to be combined, but when using a kneading extruder, it is preferable to use a biaxial extrusion kneader, and when using a static kneader, the number of divisions Is preferably 1 million or more. In addition, a combination of polymers is also important for the ultrafine dispersion of island components with a size of several tens of nm.

In order to make the island component domain (nanofiber cross section) close to a circle, the island component polymer and the sea polymer are preferably incompatible. However, it is difficult for the island component polymer to be sufficiently finely dispersed by a simple combination of incompatible polymers. For this reason, it is preferable to optimize the compatibility of the polymer to be combined, but one index for this purpose is the solubility parameter (SP value). Here, the SP value is a parameter that reflects the cohesive strength of substances defined by (evaporation energy / molar volume) ^1/2 , and a polymer alloy having good compatibility can be obtained between those having close SP values. There is sex. The SP value is known for various polymers. For example, it is described in page 189 of “Plastic Data Book” (Asahi Kasei Amidus Co., Ltd. Plastic Editing Department, published on December 1, 1999, Industrial Research Council, Inc.). Has been.

When the difference in SP value between the two polymers is 1 to 9 (MJ / m ³ ) ^1/2, it is easy to achieve both circularization and ultrafine dispersion of the island component domains due to incompatibility. For example, the difference in SP value between N6 and PET is about 6 (MJ / m ³ ) ^1/2, which is a preferable example, but the difference between N6 and PE is about 11 (MJ / m ³ ) ^1/2. This is an undesirable example.

  In addition, it is preferable that the difference in melting point between polymers is 20 ° C. or less because, particularly when kneading using an extrusion kneader, a difference in melting state in the extrusion kneader hardly occurs, so that kneading can be performed efficiently. Here, in the case of an amorphous polymer, since there is no melting point, it is replaced by the Vicat softening temperature, heat distortion temperature or glass transition temperature.

Furthermore, the melt viscosity is also important, and if the polymer forming the island is set lower, the island polymer is likely to be deformed by shearing force. . However, if the island polymer is excessively low in viscosity, it tends to be seamed and the blend ratio with respect to the whole fiber cannot be increased. Therefore, the island polymer viscosity is preferably 1/10 or more of the viscosity of the sea polymer. In addition, the melt viscosity of the sea polymer may greatly affect the spinnability, and it is preferable to use a low-viscosity polymer of 100 Pa · s or less as the sea polymer because the island polymer is easily dispersed. This can also significantly improve the spinnability. The melt viscosity here is a value at a shear rate of 1216 sec ⁻¹ at the die temperature during spinning.

  In order to improve the spinnability and spinning stability, the die temperature is preferably 25 ° C. or more from the melting point of the sea polymer, and the distance from the die to the start of cooling is 1 to 15 cm to cool the yarn.

  The spinning speed is preferably higher speed spinning from the viewpoint of increasing the draft in the spinning process, and a draft of 100 or more is preferred from the viewpoint of reducing the nanofiber diameter. The spun polymer alloy fiber is preferably subjected to stretching and heat treatment, but the preheating temperature at the time of stretching is preferably a temperature equal to or higher than the glass transition temperature (Tg) of the island polymer from the viewpoint of reducing yarn unevenness. .

  In this production method, by combining the above polymers and optimizing the spinning / drawing conditions, the island polymer is ultra-finely dispersed to several tens of nanometers, and a polymer alloy fiber with small thread spots is obtained. Thus, not only a certain cross section but also any cross section in the longitudinal direction can be used as a “polymer alloy fiber” having small island polymer diameter variation.

  The “polymer alloy fiber” spun by the above method has a single fiber fineness of 1 to 15 dtex (diameter of 10 to 40 μm), and is obtained as a focused yarn (5,000 dtex or less) in which filaments are collected. In addition, depending on the island component diameter, there are several thousand to several million island polymers (several wt% to 80 wt%) that are precursors of nanofibers in a single yarn of “polymer alloy fiber”. It is dispersed in the molecule (see FIG. 2).

  Next, a method for producing nanofibers from this “polymer alloy fiber” will be described.

  The nanofiber used in the present invention is preferably a short fiber in order to improve the uniform dispersibility and long-term storage stability of the nanofiber, and the sea component of the “polymer alloy fiber” is removed and cut into short fibers. It is preferable. Furthermore, it is preferable to beat the cut fibers.

  The nanofiber short fiber is deseamed in the state of the “polymer alloy fiber” converging yarn to obtain a nanofiber bundle and then cut (first sea removal method), or the “polymer alloy fiber” converging yarn is used. It can be obtained either by cutting and then removing the sea (post-sea removal method). Furthermore, it is preferable to beat the obtained short fibers with a beater until the nanofibers are separated.

  In the case of the pre-sea removal method, the sea component is first dissolved in the state of a “polymer alloy fiber” bundled yarn (below 5000 dtex) or a focused tow (over 5000 to several million dtex). Remove with a possible solvent (extract solution) or chemical solution, wash with water and dry, then cut to an appropriate fiber length with a guillotine cutter or slicing machine. In the case of the post-sea removal method, it is possible to dissolve the sea components after cutting into a suitable fiber length with a guillotine cutter or slicing machine in the state of the “polymer alloy fiber” bundling yarn and the state of the bundling tow. It is obtained after removing with a solvent or chemical, washing with water and drying. The fiber length of a suitable nanofiber short fiber is preferably 0.05 to 5 mm, and more preferably 0.2 to 1 mm. If the fiber length is too long, it is difficult to disperse, and if it is too short, it becomes powdery and tends to aggregate.

  Solvents and chemicals used to remove sea components from “polymer alloy fibers” include alkalis such as caustic soda and caustic potash, acids such as formic acid, trichrene, limonene, and xylene, depending on the properties of the sea component polymer. And organic solvents such as When seaming the bundled yarn or tow of the “polymer alloy fiber”, the seam can be removed in a crushed state or in a state of being wrapped around a crushed frame. However, when the sea component of the “polymer alloy fiber” in the crushed state is desealed with a solvent or chemical solution, the sea component of the “polymer alloy fiber” is usually very large, 20 to 80 wt%. The volume shrinks in the diameter direction of the casserole as it enters the sea, the “polymer alloy fibers” in the casserole closely adhere to each other, and solvents and chemicals cannot penetrate between the fibers, or the surface of the casket dissolves once and reprecipitates. It becomes difficult to remove the sea component polymer, and in the worst case, it becomes a dumpling, and it is very difficult to proceed with seawater removal of the “polymer alloy fiber”. There is a case. In order to improve this, it is possible to prevent the shrinkage of the casket by winding it around the casket frame rather than just a crushed state and suppress the adhesion between the “polymer alloy fibers”, so that the solvent always flows between the “polymer alloy fibers”. Since it becomes easy, it is preferable. By this method, sea removal can be performed not only in the bundle yarn of “polymer alloy fiber” but also in the tow state. In order to perform sea removal more efficiently, the total fineness of the tow is preferably 500,000 dtex or less, and more preferably 100,000 dtex or less. On the other hand, since the productivity of sea removal improves as the total fineness of the “polymer alloy fiber” increases, the “polymer alloy fiber” before sea removal preferably has a total fineness of 10,000 dtex or more.

  In addition, sea removal can also be achieved by decomposing a sea component polymer with a chemical solution such as alkali. In this case, sea components can be removed relatively easily even in a crushed state. This is because the sea component polymer can be easily dissolved and removed by becoming a low molecular weight substance or monomer by hydrolysis or the like. In addition, when sea components are removed by decomposition, gaps are created between the fibers, and chemicals such as alkali penetrate into the interior of the `` polymer alloy fibers '' that are the precursors of nanofibers. The sea removal speed is accelerated, and unlike sea components dissolved and removed by organic solvents, sea removal is possible even in a casket state.

  As described above, a tow or casserole composed of “polymer alloy fibers” which are nanofiber-forming fibers, that is, a nanofiber bundle obtained by treating such a fiber bundle with a solvent or a chemical solution is a nanofiber for all the fibers. The area ratio of the fiber is preferably 95 to 100%. This means that in the nanofiber bundle after seawater removal, there is almost no part that has not been seawatered, which makes it possible to minimize the incorporation of coarse fibers, which can be made later by papermaking. High-quality nanofiber synthetic paper can be obtained.

In the present invention, a “polymer alloy fiber”, that is, a fiber bundle made of nanofiber-forming fibers, is subjected to sea removal treatment with a solvent or a chemical solution in a state where the fiber density of the fiber bundle is 0.01 to 0.5 g / cm ^3. It is preferable to do. When the fiber density of the fiber bundle is smaller than 0.01 g / cm ³ when performing sea removal treatment with a solvent or a chemical solution, the shape of the fiber bundle to be treated becomes unstable, and nanofiber formation cannot be performed uniformly. There is a case. On the other hand, when the fiber density of the fiber bundle exceeds 0.5 g / cm ³ , the penetration of the solvent or the chemical solution into the fiber bundle is deteriorated, the nanofiber formation becomes incomplete, and the nanofiber content in the nanofiber bundle is reduced. May decrease. The fiber density of the fiber bundle during the sea removal treatment with a solvent or a chemical solution is more preferably 0.01 to 0.4 g / cm ³ , and still more preferably 0.03 to 0.2 g / cm ³ .

  In addition, when nanofiber bundles are obtained by the pre-sealing method, the nanofiber focusing yarn and tow obtained should be cut to an appropriate fiber length according to the purpose and purpose of the nanofiber using a guillotine cutter or slicing machine. Can do. In some cases, a focused yarn of 5000 dtex or less is further focused and cut into a tow of 5000 to several million dtex. Such a bundled yarn or tow preferably has a moisture content of 20 to 100 wt% before being cut. The nanofiber converging yarn and tow after sea removal have better converging properties if they contain a certain amount of moisture, so that they are easy to handle and the accuracy of cutting is improved, so that the uniformity of the cut length is improved. Further, since the fusion of short fibers due to heat generation at the time of cutting is suppressed, the adhesion of the short fibers to the cutting blade is reduced, and the production efficiency at the time of cutting is improved. Furthermore, it is also preferable to add 0.01 to 1 wt% (as oil agent 100%) of the oil agent to the bundle yarn and tow.

  Next, a specific method for the post-sea removal method will be described.

  The removal of short fibers obtained by cutting “polymer alloy fibers” can be achieved by placing the short fibers in an organic solvent or a chemical solution such as alkali or acid and dissolving or decomposing the sea components while stirring with a stirrer. To do. Such sea removal is usually performed by batch processing, and it is preferable to perform the processing steps in several stages. When the sea component is efficiently dissolved and removed with an organic solvent such as trichlene, the concentration of the sea component polymer dissolved in the solvent should be 6 wt% or less when the first-stage sea component is dissolved. Is preferable, and it is further more preferable to make it 3 wt% or less. At the time of sea removal after the second stage, the concentration of the polymer dissolved in the solvent is gradually decreased, and the concentration is preferably 0.1 wt% or less, and 0.01 wt% or less More preferably. Further, when the sea component is efficiently decomposed and removed by hydrolysis with a chemical solution or the like, the concentration of the sea component dissolved in the chemical solution and reduced in molecular weight or monomerized state is set to 10 wt% or less. It is preferably 5 wt% or less. During sea removal in the second and subsequent stages, the concentration of sea components dissolved in the chemical solution in a low molecular weight or monomerized state should be gradually reduced to a concentration of 0.1 wt% or less. Preferably, 0.01 wt% or less is more preferable. The short fiber obtained by cutting the “polymer alloy fiber” is treated with each solvent or chemical solution as described above, filtered through an appropriate stainless steel wire mesh filter, etc., and the nanofiber is recovered. Thoroughly wash away the solvent and chemicals adhering to the product, and dry.

  In order to perform efficient sea removal regardless of the method of seawater removal of bundled yarn, tow, and cut fiber of “polymer alloy fiber”, a solvent such as an organic solvent used for sea removal in the second stage and thereafter. It is preferable to use a new chemical solution such as alkali or acid, raise the temperature of the sea removal treatment as much as possible, and constantly circulate the solvent or chemical solution with stirring. Moreover, it is preferable to make the fiber amount ratio with respect to the solvent or chemical used for sea removal as small as possible and to reduce the concentration of the sea component in the solvent or chemical after the sea removal treatment.

  It is preferable that the bundled yarn, tow, and cut fiber containing a solvent or a chemical solution are removed to some extent by a centrifuge between the steps of the sea removal treatment after the first stage. Alternatively, it is preferable that the amount of the chemical solution is 200 wt% or less because the handleability in the next step is improved. Further, when the amount of the solvent or the chemical solution with respect to the fiber weight is 50 wt% or more, the solvent or the chemical solution between the fibers serves as a spacer, and the excessive adhesion of the fibers can be suppressed. It is preferable because sea removal efficiency is improved. Furthermore, in order to improve sea removal efficiency, when sea removal treatment is performed multiple times, washing is performed after each stage of the treatment to sufficiently remove the sea components adhering to the fiber, and then sea components mixed into the subsequent solvent or chemical solution It is preferable to reduce the amount. When sea removal with a solvent or chemical solution is completed, the residual sea component can be suppressed by washing until the sea component adhering to the fiber is preferably 0.1 wt%, more preferably 0.01 wt% or less. The nanofiber short fiber thus obtained is a fiber in which several thousand to several million nanofibers are aggregated depending on the diameter of the nanofiber.

  Next, the obtained nanofiber short fibers after sea removal are beaten with a beater. By beating, nanofiber short fibers can be separated into nanofibers one by one.

  Examples of the beater include Niagara beaters, refiners, and mills at the production level, and experimentally include home mixers and cutters, laboratory grinders, biomixers, roll mills, mortars, and PFI beaters.

  In the transmission electron microscope (TEM) or scanning electron microscope (SEM) photograph of the cross section of the nanofiber short fiber aggregate, the nanofibers are observed one by one, and a small amount of nanofibers are present on the surface. Although it can be seen that it is released from the surface of the short fiber, most of the nanofibers in the short fiber exist as an aggregate, so this aggregate is lightly squeezed or the nanofiber short fiber is placed in water and stirred. It is difficult to separate nanofibers down to the single fiber level. This is because the fiber diameter of the nanofiber is very thin and the specific surface area is significantly increased compared to the conventional ultrafine fiber. This is thought to be due to the strong interaction and large cohesion.

  For this reason, it is preferable that the nanofiber short fibers are separated by the above-described beater. However, among the beating machines, a device having a cutter or pulverized blades is liable to damage the fiber, and has the disadvantage of cutting the fiber and shortening the fiber length at the same time as the effect of separating the fiber. Although nanofibers have strong cohesive strength between fibers, the fibers are thin. Therefore, in a device having a cutter or a pulverized blade, the fiber is seriously damaged, and in severe cases, it may be pulverized into powder. For this reason, even if the fibers are beaten, it is preferable to loosen or break the agglomeration between the fibers by applying a shearing force rather than crushing or cutting force. In particular, since the PFI beating machine beats by the shearing force due to the difference in the peripheral speed between the inner blade and the outer container, the damage until the nanofibers are loosened one by one is very small and preferable. Even when other beating devices are used, the beating speed and the beating pressure can be reduced in order to reduce the beating speed and beating pressure and reduce the damage to the fibers by reducing the beating force against the nanofiber. It is preferable to process under soft conditions. Even if it is beaten for a long time under soft conditions such as a low rotation speed even in a mixer for home use or laboratory use, although it is inferior in efficiency, it can be beaten to one nanofiber in the same way as the above-described beating machine. it can.

  The beating is preferably performed separately for the primary beating and the secondary beating. In the primary beating, it is preferable to loosen the nanofiber aggregate lightly with a shearing force to reduce the number of nanofiber aggregates to some extent. The primary beating is preferably carried out until the freeness representing the degree of beating of the fibers is 500 or less, more preferably 350 or less, and more preferably 5 or more. The freeness herein refers to the Canadian standard freeness water described in JIS P 8121 “Pulp Freeness Test Method” shown in “Q. Nanofiber Freeness Test Method” in the Examples described later. It is a value measured according to the degree test method. When measuring the freeness of nanofibers, nanofibers that have been beaten and dispersed in water may clog the filter in the freeness tester container. Evaluate by water content. When performing primary beating with a Niagara beater or refiner, nanofiber short fibers are generally dispersed in water. However, if the concentration of nanofibers is 5 wt% or less, the beating is performed uniformly. ,preferable. More preferably, it is 1 wt% or less. Moreover, it is preferable that the concentration of the nanofiber is 0.1 wt% or more because the beating efficiency is improved. In the primary beating, it is preferable to increase the setting clearance of a beating machine such as a Niagara beater or a refiner to 0.5 to 2 mm because the load applied by the beating apparatus can be reduced and the beating process time can be reduced. It is also possible to soften the conditions with a laboratory pulverizer, mixer and cutter. The beaten nanofibers are collected by filtration with an appropriate wire mesh filter, etc., dehydrated and stored with a dehydrator so that the moisture content is 50 to 200%, and the nanofiber capacity after beating can be reduced and stored. It is preferable because it is easy to secure a place and handle in the next process.

  Furthermore, the secondary beating referred to in the present invention is a beating of nanofibers subjected to the primary beating more precisely. Niagara beaters, refiners, PFI beating machines, etc. can be used as the apparatus used at this time. The setting clearance of each beating machine is preferably 0.1 to 1.0 mm, and preferably 0.1 to 0.5 mm. It is more preferable to reduce the pressure, and it is preferable to process under soft conditions. When the refiner is used, the shape of the processing blade incorporated in the apparatus can be appropriately changed. However, it is preferable to select a shape having a scissor effect or shearing effect rather than cutting the fiber. In particular, it is optimal to use a PFI beating machine for experimentally performing secondary beating of nanofibers. Since the PFI beating machine beats by a shearing force due to the difference in peripheral speed between the inner blade and the outer container, the fiber damage until the nanofibers are beaten one by one is very small and more preferable. In addition, the fiber concentration of the nanofibers during beating can be increased to 5 to 20 wt%, and the inner wing part of the beating machine is always uniformly applied to the fibers, so that the nanofiber aggregate becomes thin according to the beating. Thus, even if the strength of the fiber is lowered, the fiber can be uniformly beaten without being further cut or powdered in the fiber length direction.

  Thus, the freeness of the nanofiber dispersion obtained by secondary beating is preferably 350 or less, more preferably 200 or less, still more preferably 100 or less, and more preferably 5 or more. When the freeness exceeds 350, the beating degree is small, and it may be difficult to uniformly disperse the nanofibers in the solvent. When performing secondary beating with Niagara beaters, refiners, home and laboratory mixers, cutters, etc., the nanofiber concentration in the water is processed at a low concentration, so the nanofibers that become thin and float according to the beating are floated. Since the rotating blade hits repeatedly locally, the effect of cutting and crushing the fiber is great, and it is easy to cut or powder in the fiber length direction, so beating with mild beating conditions such as blade shape, rotation speed, pressurizing condition etc. It is preferable to do.

  In order to prevent re-aggregation, the nanofibers beaten in this way are beaten in water or in a solvent, and then collected by filtration with a filter, so that the content of water or solvent becomes 50 to 200 wt% with a dehydrator. Thus, it is preferable to store after dehydration (desolvation). When it is absolutely necessary to dry and store, freeze drying or vacuum drying at a low temperature of 60 ° C. or lower is preferable.

  The above-described beating of the nanofiber was performed in water. However, when it is necessary to beat in a special solvent, it is preferable to beat in a solvent.

  In the conventional beating of cellulose and synthetic fibers, a method is used in which the fibers are beaten in water and then dried, and the dried fibers are dispersed with a stirrer in the intended emulsion or solvent. With ultrafine fibers, it was possible to redisperse the fibers in a solvent or water even by this method. However, in the case of nanofibers, as shown in Table 1, since the specific surface area of the fibers is very large, the fibers dispersed in the bent water by beating are re-agglomerated during drying and dispersed with a normal stirrer. However, uniform dispersion was difficult. For this reason, it is preferable to directly beat in at least one selected from the group consisting of water, oil, and organic solvent. As the solvent, a mixed solution of an organic solvent and water may be preferable. General beating machines are usually beaten in water and are not compatible with organic solvents, so they can be explosion-proof, work environment measures to collect evaporated solvent, and depending on the solvent, wear a mask during work. Safety measures such as are necessary. Use a kneader or kneader instead of a stirrer when blending nanofibers into gel-like materials such as facial cleansing gels, hair styling gels, poultice gels, ointments and other highly viscous creams or emulsions. Is preferred.

  Direct beating in an organic solvent requires a special explosion-proof beating machine and safety measures, which may require a large capital investment. In order to avoid this problem, a method for substituting the organic solvent with water contained in the nanofiber beaten in water will be described below.

  As described above, the nanofiber short fiber beaten in water is preferably 0.3 to 300 times, more preferably 2 to 100 times the moisture ratio of the nanofiber to the fiber weight with a dehydrator. . Thereby, re-aggregation of nanofibers can be suppressed. Since nanofibers have a large specific surface area, water retention is high, and even when the water ratio to nanofibers is as high as about 10 times, water can be retained between fibers, so that water does not drip so much. And much more water than conventional fibers relative to the fiber weight. In order to obtain a good dispersion state of the nanofibers, it is preferable that the moisture ratio of the nanofibers to the fiber weight is 5 to 30 times. However, if the water ratio is too large, the efficiency of solvent replacement decreases.

  Next, the dehydrated nanofibers are placed in an arbitrary container, and a solvent to be replaced is charged. The solvent added in the first time is preferably 2 to 50 times, more preferably 5 to 20 times the water content of the nanofibers. The type of solvent varies depending on the type and application of the nanofiber polymer, and the purpose, but it is preferably a hydrophilic solvent that is compatible with water because it substitutes with water. Alcohol-based, ether-based, ester Solvents such as those based on ketone, ketone and DMF are preferred.

  After the addition of the solvent, the water contained in the nanofiber and the added solvent are stirred for 5 to 60 minutes by a stirrer in the container. After stirring, the nanofiber and the solution are separated from the remaining solution using, for example, a wire mesh filter. However, in order to maintain dispersibility, the amount of the remaining solution contained in the nanofiber should be at least 1 times the fiber weight of the nanofiber. It is preferable to separate.

  The number of times of solvent replacement is preferably 2 times or more, and more preferably 5 times or more. The operation can be accomplished by repeating the operation of charging the solvent and separating the nanofibers from the mixed solution of the solvent and water several times. Although this method can maintain the dispersibility of the nanofibers well in a solvent, there is a problem that water remains slightly.

  In the above method, even if the water ratio at the time of dehydration is centrifuged and concentrated to 10 to 50 wt%, the remaining water can be considerably reduced by repeating solvent replacement. However, when nanofibers are later dispersed in the solvent The dispersibility of the resin may decrease. Moreover, although solvent substitution by the Soxhlet method is possible, the dispersibility of the nanofiber may also be lowered.

  Next, the adjustment method of a nanofiber compound solution is demonstrated.

  The beaten nanofibers and solvent are placed in a stirrer and dispersed to a predetermined concentration. Although it depends on the single fiber diameter of the nanofiber to be produced, the concentration of the nanofiber in the total solution is preferably 5 wt% or less, more preferably 0.0001 to 1 wt%, and 0.01 to 1 wt. % Is more preferable. In addition, since nanofibers easily aggregate, it is preferable to adjust the dispersion at as low a concentration as possible in order to prevent reaggregation. Furthermore, it is preferable to add a dispersant in order to improve the dispersibility of the nanofibers. The dispersant used in the aqueous system is preferably selected from anionic systems such as polycarboxylates, cationic systems such as quaternary ammonium salts, and nonionic materials such as polyoxyethylene ethers and polyoxyethylene esters. In order to select an appropriate dispersant, for example, when dispersing by repulsion of electric charge between nanofibers, the type of the dispersant is selected according to the surface potential (zeta potential). In the case of nanofibers with a zeta potential in the range of −5 to +5 mV at pH = 7, it is preferable to add a nonionic dispersant, and when the zeta potential is −100 mV or more and less than −5 mV, an anionic dispersant Is preferably added, and when the zeta potential exceeds +5 mV and is 100 mV or less, it is preferable to add a cationic dispersant. For example, in N6 nanofibers, the zeta potential (pH = 7 vicinity) measured by laser Doppler electrophoresis is -14 mV, and the surface is negatively charged. To increase the absolute value of this potential, an anionic dispersion is used. When the agent is used, the zeta potential becomes −50 mV, so that dispersibility is improved. In addition, when dispersed by steric repulsion, if the molecular weight becomes too large, the effect as a flocculant rather than a dispersant increases, so it is preferable to control the molecular weight of the dispersant, and the molecular weight of the dispersant is 1000 It is preferably ˜50000, more preferably 5,000 to 15000.

  However, even a dispersant with the same chemical composition is affected by the molecular weight, the type of polymer that makes up the nanofiber, the concentration of the fiber, and other compounding agents, so it depends on the type, application, and purpose of the nanofiber. It is preferable to prepare an appropriate solution by selecting an appropriate dispersant. The concentration of the dispersing agent is preferably 0.00001 to 20 wt%, more preferably 0.0001 to 5 wt%, and still more preferably 0.01 to 1 wt% with respect to the entire blended solution. An effect is obtained. Moreover, in the case of the compounding solution which mix | blended such a nanofiber, it is preferable that the fiber length of a nanofiber shall be 0.05-5 mm, and it is more preferable to set it as 0.2-1 mm. In addition, when the solvent exhibits hydrophobicity such as an oily solvent or an organic solvent, it is preferable to use an acrylamide-based, silicone-based or fluorine-based dispersant.

  Next, a method for adjusting the nanofiber emulsion will be described.

  In the case of emulsions, there are roughly two types of emulsions: O / W type (type in which oil is dispersed in water) and W / O type (type in which water is dispersed in oil). Further, depending on the type of polymer constituting the nanofiber, the nanofiber may be easily dispersed in W (water) or may be easily dispersed in O (oil). In addition to the type of polymer of nanofiber, the type of W (water) and O (oil) in the emulsion, the mixing ratio, the type and mixing ratio of the dispersant, the type of added solvent, the temperature, etc. It is preferable to select the type of emulsion accordingly. Moreover, when blending various components, it is preferable to design the blending ratio of each component in the emulsion in consideration of the familiarity between the nanofiber and the compounding agent and the dispersibility of the nanofiber.

  Regardless of the type of emulsion, the concentration of nanofibers is preferably 5 wt% or less, and more preferably 0.0001 to 1 wt% from the viewpoint of the uniform dispersibility of the nanofibers. In order to ensure the above, it is more preferable that the addition concentration of the nanofiber is 0.001 to 0.5 wt%, which is a lower concentration. In addition, it is preferable to select an appropriate dispersant according to the type of nanofiber, its use and purpose, and adjust the emulsion. The method for selecting an appropriate dispersant is as described above. The concentration of the dispersant is preferably 0.00001 to 20 wt%, more preferably 0.0001 to 5 wt%, and still more preferably 0.01 to 1 wt%, based on the total amount of the emulsion. Is obtained. Furthermore, although the fiber diameter of nanofibers is very small at the nano level, the fiber length is larger than the diameter, so that it is difficult to disperse compared with so-called nano fine particles. For this reason, the fiber length of the nanofiber for emulsion is preferably 0.05 to 2 mm, and more preferably 0.05 to 0.8 mm. If nanofibers are treated with a surface treatment agent such as an oil agent (for example, a silicone-based oil agent) and added to an emulsifier, nanofibers alone may be dispersed to form an emulsion.

  Next, the nanofiber gel structure will be described, and the nanofiber gel structure will be described together.

  Although nanofibers depend on the type of polymer that composes them, they become “gel structures” when the fiber concentration is 5 to 60 wt% with respect to water (or other solvent), which is a unique phenomenon. . Here, the gel structure is composed of nanofibers and water (or other solvent), the nanofiber content is relatively high, and the fibers are in a state of 5 to 60 wt%. This is a state that is neither an aqueous solution nor a solid. Further, since there is no cross-linked structure between the polymers constituting the nanofiber, it is hereinafter referred to as “gel structure”. Normal fibers and ultrafine fibers are in a low-viscosity aqueous solution (or solution) state at this concentration, but in the case of nanofibers, the specific surface area of the fibers is large and the hydration effect between the fibers is very large (Table 1). Therefore, it is considered that such a unique phenomenon appears. In order to produce a gel structure, when beating nanofibers, the concentration can be in a high concentration range of 10 to 30 wt%.

  Further, in the present invention, the “gel-like product” means a gel-like material obtained by blending a nanofiber with a solvent or gel, and blending a certain material as needed. It refers to polymer gels such as gels and acrylamide gels, and natural material gels such as polysaccharides. In addition, the above-mentioned “gel structure” of nanofibers is included in the “gel-like product” of the present invention because it has a pseudo gel state although it does not have a crosslinked structure. A gel-like material in which nanofibers are blended at a high concentration can be prepared by setting the concentration at the time of beating nanofibers to 10 to 30 wt%. In addition, when a high concentration nanofiber gel is obtained, the dispersion uniformity can be improved by adding an acrylamide-based, silicone-based, or fluorine-based dispersant. The method for selecting an appropriate dispersant is as described above, and anionic, cationic, and nonionic dispersants can also be suitably used. Moreover, it is preferable that the density | concentration of a dispersing agent is 0.00001-20 wt% with respect to the whole gelled material, More preferably, it is 0.0001-5 wt%, More preferably, it is 0.01-1 wt%, A sufficient dispersion effect can be obtained. When preparing a gel-like product containing nanofibers at a low concentration, for example, a natural gel or a synthetic gel is added to a nanofiber-containing solution of 0.01 to 1 wt. Can be produced. Natural gels and synthetic gels include protein gels such as collagen, gelatin, and chitosan, natural gels such as agarose, alginic acid, pectin, and polysaccharide gels, and gels such as cellulose. PVA gels, crosslinked vinyl polymers, and acrylamides Examples include gels, synthetic polymer gels such as acrylic acid and alkali metal salt, alkaline earth metal salt gel, silicone gel, fluorine gel, urethane gel, and radiation-crosslinked polymer gel. In the case of a gel-like material containing such nanofibers, the fiber length of the nanofibers is preferably 0.05 to 2 mm, and more preferably 0.2 to 1 mm.

  Specific examples of blended solutions, emulsions, and gels and processed products using the nanofibers of the present invention will be described in the following examples, but the requirements of the present invention are not limited by the examples. .

  Hereinafter, the present invention will be described in detail with reference to examples. In addition, the measuring method in an Example used the following method. The measurement results in Examples and Comparative Examples are listed in Tables 3 to 5.

A. Polymer melt viscosity The polymer melt viscosity was measured by Toyo Seiki Capillograph 1B. The polymer storage time from sample introduction to measurement start was 10 minutes.

B. Melting | fusing point The peak top temperature which shows melting | dissolving of a polymer by 2nd run was made into melting | fusing point of a polymer using Perkin Elmaer DSC-7. The temperature rising rate at this time was 16 ° C./min, and the sample amount was 10 mg.

C. Color tone (b ^* value):
The b ^* of the sample was measured using a color meter MINOLTA SPECTROPHOTOMETER CM-3700d. At this time, D ₆₅ (color temperature 6504K) was used as a light source, and measurement was performed in a 10 ° visual field.

D. Mechanical Properties of Polymer Alloy Fiber 10 m of sample fiber was collected from the nonwoven fabric, and its weight was measured as n number = 5 times, and the fineness (dtex) was obtained from the average value. Then, at room temperature (25 ° C.), an initial sample length = 200 mm, a pulling rate = 200 mm / min, and a load-elongation curve was obtained under the conditions shown in JIS L1013. Next, the load value at the time of breaking was divided by the initial fineness, which was used as the strength, and the elongation at break was divided by the initial sample length to obtain a strength / elongation curve.
E. Worcester spots of polymer alloy fibers (U%)
Measurement was performed in the normal mode at a yarn feeding speed of 200 m / min using a USTER TESTER 4 manufactured by Zerbegger Worcester. F. Cross-sectional observation of “polymer alloy fiber” by TEM Ultra-thin sections were cut in the cross-sectional direction of the fiber, and the cross-section of the fiber was observed with a transmission electron microscope (TEM). Nylon was metal dyed with phosphotungstic acid.

TEM apparatus: H-7100FA type manufactured by Hitachi, Ltd. Number average diameter of island component (nanofiber precursor component) in “polymer alloy fiber” The number average diameter of the island component is determined as follows. In other words, the diameter of 300 island components randomly extracted in the same cross-section using the image processing software (WINROOF) of the island component cross-section photograph by TEM is measured, and the individual data are integrated and divided by the total number. A simple average value was obtained. This was performed at five locations 10 m apart from each other as the length of the “polymer alloy fiber”, a total of 1500 diameters were measured, and the average diameter was defined as the “island component number average diameter”.

H. SEM observation of nanofiber In the case of a nanofiber mixed solution or emulsion, the solution is sampled and placed on a film or glass plate and dried at 60 ° C. A sample of 5 mm square is collected from an arbitrary dried place, platinum is deposited, and nanofibers in the sample are observed with an ultra-high resolution electrolytic emission scanning electron microscope (UHR-FE-SEM) manufactured by Hitachi. In the case of a gel-like material, if the form is stable and can be measured in a gel state, it is dried as it is, and after drying, platinum is deposited and SEM observation is performed. If the form is not stable, dissolve in an appropriate solvent, and then observe in the same manner as the above solution.

I. Nanofiber single fiber average diameter φm
The single fiber number average diameter φm is determined as follows. That is, the diameter of 30 single fibers randomly extracted from a sample of 5 mm square using the image processing software (WINROOF) from the nanofiber surface photograph taken in the above section H is measured, and the total number is obtained after integrating the individual data. The simple average value was obtained by dividing by. Sampling was performed a total of 10 times to obtain data on the diameter of 30 single fiber fibers, and a simple average from the data on the diameter of 300 single fibers was defined as “average number of single fibers φm”. J. et al. Evaluation of Sum Pa of Single Fiber Ratio of Nanofibers The sum Pa of the single fiber ratio is obtained from the equation (3) described in the “Best Mode for Carrying Out the Invention” using the measured data. The variation becomes smaller as Pa is larger. Evaluation of single fiber diameter concentration index Pb of nanofibers Evaluation of single fiber diameter concentration Pb was described in the column of [Best Mode for Carrying Out the Invention] using the data measured in the above section I. (5) Evaluate with the formula. This means the degree of concentration of variation around the number average diameter of single fibers, and the higher the fineness ratio, the smaller the variation.

L. Nanofiber Freeness Test Method According to the Canadian standard freeness test method of JIS P 8121 “Pulp Freeness Test Method”, the freeness tester manufactured by Kumagaya Kikai Co., Ltd. was used. One liter of a 0.30 ± 0.05% aqueous solution of nanofibers was weighed in a room at 20 ° C., put into the Canadian freeness tester, and measured three times to obtain the average number of single fibers. Using the JIS correction table, the data is corrected by the deviation of the concentration from 0.30% to obtain the freeness.

M.M. Moisturizing index (ΔWR10)
About 1.0 g of the fiber for measurement is removed, the oil is removed with a detergent and a solvent, washed with water, dried, conditioned for 24 hours at 20 ° C. and a humidity of 65%, and the weight is precisely weighed to obtain W0. The fiber is immersed in water for 12 hours and then taken out and dehydrated with a centrifuge or a dehydrator so that the water content becomes 60% ± 10%. A balance is put in a transparent box adjusted to a temperature of 20 ° C. and a humidity of 25%, and a plastic container having a diameter of 5 cm and a height of 1 cm is placed on the balance. The fiber for measurement is put in a plastic container, and the weight Wi of the fiber to be dried and reduced is measured every minute until the water content becomes 10% or less. The moisture content WRi (%) at each time is expressed by the following equation.

WRi = 100 × (Wi−W0) / W0 (7)
WRi is plotted on a graph with respect to each time, and a tangential line when WRi is 30% is drawn to calculate “moisture percentage decrease rate ΔWR10 per 10 minutes” from the slope ΔWR30. This measurement is repeated 5 times and a simple average is taken as the moisture retention index (ΔWR10). ΔWR30 is a drying rate of the fiber having a moisture content of about 30%, and a smaller value indicates better moisture retention. The moisture content of the skin is about 15 to 20%, and the moisture retention index of the fiber takes into account the moisture content of the skin and uses the drying rate as an index when the moisture content is 30%.

N. Water retention index (WI)
About 1.0 g of the fiber for measurement is removed, the oil is removed with a detergent and a solvent, washed with water, dried, conditioned for 24 hours at 20 ° C. and a humidity of 65%, and the weight is precisely weighed to obtain W0. A 50 mesh stainless steel wire mesh (weight Ws) having a size of 5 cm × 10 cm attached to a metal frame having a width of 6 mm and a thickness of 2 mm is tilted at 45 ° and fixed. The fiber is taken out after being immersed in water for 12 hours, placed on the stainless steel wire net, and left for 2 minutes in an environment of 20 ° C. and humidity of 65%. The weight (Wt) of the wire mesh on which the fiber is placed is measured. The water retention index WI is expressed by the following equation.

WI = 100 × (Wt−Ws) / W0 (8)
The greater the water retention index, the better the water retention.

O. Settling time (dispersion stability evaluation)
The fiber solution is placed in a sample bottle with a diameter of 30 mm and a height of 10 cm with a tight stopper up to a height of 8 cm, shaken well by hand, and left to stand. Mark a red line at 4 cm from the bottom of the sample bottle. When the rotation of the fibers in the solution ceases, the state of the fibers that are pushed down and settling is observed in an environment of 20 ° C. The time Ts when the upper surface where the nanofibers exist settles to the red line is defined as the sedimentation time. The longer the sedimentation time, the better the dispersion stability.

P. Transparency Pure water is put in a standard sample cell of a spectrophotometer U-3400 manufactured by Hitachi, Ltd., a measurement solution is put in the other cell, and the average transmittance Tr is measured with a light source having a wavelength of 500 nm. The higher the light transmittance, the better the transparency.

Q. Measurement of the area ratio of the nanofibers The cross section of the nanofiber fiber bundle from which the sea component was removed from the polymer alloy fiber was observed with a TEM, and the cross-sectional area of the entire fiber bundle (Sa) was 1 to 500 nm present in the fiber bundle. The total area of the nanofibers was defined as (Sb), and the following formula was used.

Nanofiber area ratio (%) = (Sb / Sa) × 100 (9)
R. Zeta potential measurement 0.001M KCl was added in advance to the nanofiber blend solution or dispersion, and the pH was measured with an electrophoretic light scattering photometer ELS-800 (manufactured by Otsuka Electronics Co., Ltd.).

Example 1
Example of preparation of “polymer alloy fiber”, beating of nanofibers using a commercial beating machine, and preparation of nanofiber-containing gel structure Melt viscosity 53 Pa · s (262 ° C., shear rate 121.6 sec ⁻¹ ), melting point 220 ° C. Copolymerized PET having a melting point of 225 ° C. obtained by copolymerization of N6 (20 wt%), melt viscosity of 310 Pa · s (262 ° C., shear rate of 121.6 sec ⁻¹ ), melting point of 225 ° C. isophthalic acid and 8 mol% of bisphenol A (80 wt%) was kneaded at 260 ° C. with a twin-screw extruder kneader to obtain a polymer alloy chip having a b ^* value = 4. The copolymerized PET had a melt viscosity of 180 Pa · s at 262 ° C. and 1216 sec ⁻¹ . The kneading conditions at this time were as follows.

Screw type Same direction complete meshing type Double thread screw Screw diameter 37mm, effective length 1670mm, L / D = 45.1
The kneading part length is 28% of the effective screw length
The kneading part was located on the discharge side from 1/3 of the effective screw length.

There are three backflow sections along the way. Polymer supply N6 and copolymerized PET were weighed separately and supplied separately to the kneader.

260 ° C
2 vents

A model diagram of a melt spinning apparatus used for melt spinning is shown in FIG. In the figure, 1 is a hopper, 2 is a melting section, 3 is a spin block, 4 is a spinning pack, 5 is a base, 6 is a chimney, 7 is a melted and discharged yarn, 8 is a converged oiling guide, and 9 is a first A take-up roller, 10 is a second take-up roller, and 11 is a take-up thread. This polymer alloy chip was melted in the melting part 2 at 275 ° C. and led to the spin block 3 at a spinning temperature of 280 ° C. The polymer alloy melt was filtered with a metal nonwoven fabric having a limit filtration diameter of 15 μm, and then melt-spun from the die 5 with a die surface temperature of 262 ° C. At this time, a base having a measuring portion having a diameter of 0.3 mm above the discharge hole, having a discharge hole diameter of 0.7 mm and a discharge hole length of 1.75 mm was used. And the discharge amount per single hole at this time was 2.9 g / min. Furthermore, the distance from the base lower surface to the cooling start point (the upper end of the chimney 6) was 9 cm. The discharged yarn is cooled and solidified over 1 m with cooling air of 20 ° C., and is supplied by an oil supply guide 8 installed 1.8 m below the base 5, and then the unheated first take-up roller 9 and second take-up roller 10 was wound up at 900 m / min. The spinnability at this time was good, and there was no yarn breakage during continuous spinning for 24 hours. This was subjected to a stretching heat treatment with the first hot roller at 98 ° C. and the second hot roller at 130 ° C. At this time, the draw ratio between the first hot roller and the second hot roller was 3.2 times.
The obtained polymer alloy fiber exhibited excellent properties of 120 dtex, 12 filaments, strength 4.0 cN / dtex, elongation 35%, U% = 1.7%. Further, when a cross section of the obtained “polymer alloy fiber” was observed with a TEM, N6 was an island component (round portion), and copolymer PET was a sea island component structure of the sea (other portion) (see FIG. 2). ), The diameter of the island component N6 was 53 nm, and a “polymer alloy fiber” in which N6 was ultrafinely dispersed was obtained.

  The 120 dtex, 12 filament “polymer alloy fiber” was cut into 2 mm with a guillotine cutter. The cut “polymer alloy fiber” is treated with 98 ° C., 10% sodium hydroxide for 1 hour, the polyester component of the sea component is removed, filtered through a filter, and further dehydrated with a centrifuge until the water content is about 100%. Short fibers were obtained. The short fibers were washed with water and dehydrated five times to remove sodium hydroxide to obtain nanofiber aggregate short fibers. About 20 liters of water and 30 g of the short fibers were put into a Niagara beater, and the fibers were first beaten for 10 minutes. The freeness of the nanofiber subjected to the first beating was 362. Water was removed from this fiber with a centrifugal separator to obtain 250 g of primary beating fiber having a fiber concentration of 12 wt%. This primary beating fiber was secondarily beaten for 10 minutes with a PFI beating apparatus, and then dehydrated to obtain 250 g of secondary beating fibers having a concentration of 10 wt% of nanofibers. The freeness of the nanofibers subjected to secondary beating was 64. The nanofibers having a concentration of 10 wt% were not liquid and became a soft solid gel-like material even when they were placed in a reagent bottle and shaken even though they contained water 10 times or more. In order to evaluate the form of nanofibers in the gel-like material, the gel-like material was diluted with water as shown in Example 6 to prepare a 0.01 wt% nanofiber compound solution, and the number average single fiber diameter φm Then, the sum Pa of single fiber ratios and the concentration index Pb of single fiber diameters were evaluated. A distribution table of single fiber diameters is shown in Table 3. The nanofibers in the nanofiber-containing gel-like product had φm of 60 nm, Pa of 100%, and Pb of 66%.

Examples 2 and 3
Example of nanofiber mixture solution in which nanofiber aggregate is beaten with lab mixer for a long time 7.0 g of nanofiber aggregate short fiber having a fiber length of 2 mm obtained by removing the “polymer alloy fiber” of Example 1 ( Dry conversion weight: containing 110% water) and water were put in a lab mixer to 500 cc, (1) dispersed in a lab mixer at 6000 rpm for 30 minutes, and (2) a solution filtered through a 50 mesh stainless steel wire mesh. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated three times. By this operation, a nanofiber compound solution having a concentration of about 1.0 wt% was obtained. 10 g of the blended solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured to find 1.1 wt%. Further, water was added to prepare a 1.0 wt% concentration nanofiber compound solution. The mixed solution corresponds to a state of 1.0 wt% of the fiber after secondary beating in Example 1. The freeness of this nanofiber was 157. Although the freeness was higher than the nanofiber after the secondary beating of Example 1 and the beating property of the lab mixer was slightly low, nanofibers with good dispersibility were obtained by stirring repeatedly for a long time. 70 g of the 0.10 wt% concentration nanofiber blending solution and water are put in a laboratory mixer to make 500 cc, and dispersed at 6000 rpm for 30 minutes to reduce the nanofiber concentration, thereby reducing the 0.10 wt% nanofiber blending solution (Example) 2) was obtained.

  Furthermore, the same operation as in Example 2 was performed to dilute the 0.10 wt% aqueous solution 10 times to obtain a nanofiber blending solution (Example 3) having a concentration of 0.01 wt%. For each blended solution of Examples 2 and 3, single fiber number average diameter φm, single fiber ratio sum Pa, single fiber diameter concentration index Pb are evaluated, φm is 63 nm, Pa is 100%, Pb Although 61% was beaten with the lab mixer, a mixed solution in which nanofibers were dispersed to the same extent as in Example 1 was obtained. Further, when the dispersion stability of the nanofiber was evaluated, the sedimentation time was 12 minutes (Example 3), 2.7 minutes (comparative example 2) of the conventional normal fiber (diameter 27 μm), and ultrafine fiber (diameter 2 μm). Compared to 1.1 minutes (Comparative Example 4), the sedimentation time was slow and the dispersion stability was good. Further, the precipitated nanofibers could be easily redispersed by stirring. In addition, the transparency of the blend solutions of Examples 2 and 3 was 1.8% and 53%, which was the same as the transparency of Example 6 in which the nanofiber blended gel material beaten in Example 1 was thinned. . Further, in Examples 2 and 3, the freeness is slightly higher than in Example 1, and the beating degree of the nanofiber is slightly inferior, but the single fiber number average diameter φm, the single fiber ratio sum Pa, the single fiber diameter The degree of concentration index Pb was approximately the same as in Example 1, and the nanofibers could be dispersed by beating even with a lab mixer.

Comparative Examples 1 and 2
Example of aqueous solution of conventional ordinary fiber having a diameter of 27 μm A commercially available nylon fiber having an average number of single fibers of 30 μm is cut into 2 mm, 0.7 g of the fiber and water are put in a lab mixer to make 500 cc, and (1) 6000 rpm in the lab mixer. And (2) a solution filtered through a 50 mesh stainless steel wire mesh was obtained. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated three times. By this operation, an aqueous solution of nylon fibers having a concentration of about 0.1 wt% was obtained, but the fibers were not beaten at all. 10 g of the aqueous solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 0.13 wt%. Further, water was added to prepare an aqueous solution of 0.10 wt% nylon fiber (Comparative Example 1). 70 g of the 0.10 wt% concentration aqueous solution and water were placed in a lab mixer to make 500 cc, and dispersed with a lab mixer at 6000 rpm for 30 minutes to obtain a 0.01 wt% nanofiber aqueous solution (Comparative Example 2).

  For the aqueous solutions of Comparative Example 1 and Comparative Example 2, the single fiber number average diameter φm, the single fiber ratio sum Pa, and the single fiber diameter concentration index Pb were evaluated. Unlike the nanofiber of Example 2 in which Pb was beaten at 92%, the nylon fiber could not be beaten. Further, when the dispersion stability of the 0.01 wt% aqueous solution of Comparative Example 2 was evaluated by the sedimentation time, it settled fairly quickly as 2.7 minutes, and the dispersion stability was not good. Further, when the transparency of the aqueous solution was evaluated, in Comparative Examples 1 and 2, the transparency was 66% and 87%, respectively. This is because the nylon fibers of Comparative Examples 1 and 2 are larger in diameter than the nanofibers, and the number of nylon fibers per unit volume in the aqueous solution is very small.

Comparative Examples 3 and 4
Example of conventional ultrafine fiber aqueous solution with a diameter of 2 μm As described in JP-A-53-106872, using nylon 6 (N6: 60 wt%) island component having a melting point of 220 ° C. and polystyrene (PS) as a sea component. A sea-island component composite yarn was drawn and drawn to obtain an island-component composite drawn yarn. Then, as described in the examples of the Japanese Patent Application Laid-Open Publication No. SHO 60, PS was removed by 99% or more by trichlorethylene treatment to obtain N6 ultrafine fibers having a diameter of about 2 μm. When the cross section of the fiber was observed with a TEM, the single fiber diameter of the ultrafine fiber was 2.2 μm. N6 extra fine fiber is cut into 2 mm, 0.7 g of the fiber and water are put into a lab mixer to make 500 cc, (1) dispersed at 6000 rpm for 30 minutes in a lab mixer, and (2) a solution filtered through a 50 mesh stainless steel wire mesh. Obtained. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated three times. By this operation, an aqueous solution of N6 ultrafine fibers having a concentration of about 0.1 wt% was obtained. In the aqueous solution, the fibers became flocs having a size of several mm to 15 mm and were not sufficiently dispersed in the aqueous solution. . 10 g of the aqueous solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 0.12 wt%. Further, water was added to prepare an aqueous solution of N6 ultrafine fibers having a concentration of 0.10 wt% (Comparative Example 3). 70 g of the 0.10 wt% aqueous solution and water are put into a lab mixer to make 500 cc, and dispersed in the lab mixer at 6000 rpm for 30 minutes to reduce the nylon fiber concentration in the aqueous solution, and 0.01 wt% N6 extra fine fiber An aqueous solution (Comparative Example 4) was obtained. Although the aqueous solution had a smaller floc size than Comparative Example 3, it became a cluster of 1 mm to 5 mm in the aqueous solution, and the cluster easily aggregated, and the N6 ultrafine fibers settled when left standing. It was easy. The 0.01 wt% aqueous solution was evaluated for the number average single fiber diameter φm, the sum of single fiber ratios Pa, and the concentration index Pb of single fiber diameters. As a result, φm was 2.1 μm, Pa was 0%, Pb 88%, and unlike the nanofibers of Example 2, the nylon fibers could not be beaten. The dispersion stability of the 0.01 wt% aqueous solution of Comparative Example 4 was evaluated by sedimentation time. As a result, the dispersion sank as early as 1.1 minutes, and the dispersion stability was not good. Further, the transparency of the aqueous solution was 14% and 52% in Comparative Example 3 and Comparative Example 4, respectively.

Examples 4, 5, and 6
Example of preparation of low-concentration nanofiber-containing solution from high-concentration nanofiber-containing gel of Example 1 150 g of 10 wt% nanofibers after secondary beating obtained in Example 1 were collected and 850 g of water was added. (1) Dispersed for 5 minutes at 6000 rpm with a laboratory mixer, and (2) filtered through a 50 mesh stainless steel wire mesh. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated 5 times. By this operation, a nanofiber compound solution having a concentration of about 1 wt% was obtained. 10 g of the solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 1.12 wt%. Further, water was added to prepare a nanofiber compound solution (Example 4) having a concentration of 1.00 wt%. After 150 g of the nanofiber compound solution having a concentration of 1.00 wt% was collected, 850 g of water was added, and the above operations (1), (2), (3) (the number of operations of (3) was three times) were performed. Concentration adjustment was performed to obtain a nanofiber combination solution (Example 5) having a concentration of 0.10 wt%. Collect 150g of 0.10wt% concentration nanofiber solution, add 850g of water, and perform the above steps (1), (2), (3) (the number of operations in (3) is 3 times) and then the concentration. Adjustment was performed to obtain a nanofiber blending solution (Example 6) having a concentration of 0.01 wt%. The zeta potential of the nanofiber combination solution of Example 6 was measured and found to be -14 mV. When the dispersion stability of the nanofiber compound solution of Example 6 was evaluated by sedimentation time, the conventional fiber was 2.7 minutes (Comparative Example 2) and the ultrafine fiber was 1.1 minutes (Comparative Example 4). On the other hand, the settling time of the nanofiber in the nanofiber mixture solution of Example 6 was 10 minutes, and the dispersibility of the nanofiber was better than that of the conventional fiber. In addition, the dispersion of the ultrafine fiber is slightly worse than that of the normal fiber. The dispersion of the ultrafine fiber is a large flock of 3 to 10 mm because the normal fiber is scattered in the aqueous solution. Because. Moreover, the transparency of the compound solutions of Examples 4, 5, and 6 was 0%, 1.2%, and 51%, respectively. As for the nanofibers in the blended solution of Example 6, the single fiber number average diameter φm, the single fiber ratio sum Pa, and the single fiber diameter concentration index Pb were evaluated. As a result, φm was 60 nm, Pa was 100%, Pb was 66%.

Examples 7, 8, and 9
Example of adding a dispersant to Examples 4 to 6 An anionic dispersant in which the main component manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. is sodium polyacrylate in the nanofiber compound solution prepared in Examples 4, 5, and 6 ( Charol AN-103: molecular weight 10,000) was added to each compounded solution so that the concentration was 0.10 wt%, and stirred to obtain compounded solutions of Examples 7-9. The zeta potential of the nanofiber combination solution of Example 9 was measured and found to be −50 mV. When the dispersion stability of the nanofiber compound solution of Example 8 was evaluated by sedimentation time, the conventional fiber was 3.7 minutes (Comparative Example 5) for normal fibers and 1.3 minutes (Comparative Example 6) for ultrafine fibers. On the other hand, the nanofiber combination solution of Example 8 was 360 minutes. When the settling times of Example 6 and Example 9, Comparative Examples 2 and 5, and Comparative Examples 4 and 6 are compared, the effect of adding the dispersant is the largest in the nanofiber compound solution, and the conventional normal fiber or ultrafine fiber is effective. In comparison, the dispersibility of nanofibers is dramatically improved by the addition of a dispersant (36 times that of no additive). Further, the transparency of the blended solutions of Examples 7, 8, and 9 was 0%, 2.4%, and 63%, respectively, and the blended solution of 0.10 wt% concentration of Example 8 and 1. Although there was no effect of improving the transparency with respect to the 0 wt% concentration of the blended solution, the 0.01 wt% concentration of the blended solution of Example 9 was compared with Example 6 in which the dispersant was not added. Thus, the effect of improving the transparency of 10% or more was obtained. When the concentration of nanofibers in the compound solution is high, the number of nanofibers per unit volume of the compound solution becomes enormous, and even if a dispersant is added, the dispersibility is not improved so much. When the transparency of the blended solution is required, it is preferable to suppress the number of nanofibers per unit volume of the blended solution, and the nanofiber concentration is preferably 0.05 wt% or less.

Comparative Examples 5 and 6
Example of adding dispersant to aqueous solutions of conventional normal fibers and ultrafine fibers of Comparative Examples 2 and 4 The main component manufactured by Daiichi Kogyo Seiyaku Co., Ltd. is sodium polyacrylate in the aqueous solutions prepared in Examples 2 and 4. An anionic dispersant (Charol AN-103: molecular weight 10,000) was added so as to have a concentration of 0.10 wt%, and stirred to obtain aqueous solutions of Comparative Examples 5 and 6. When the dispersion stability of the aqueous solutions of Comparative Examples 5 and 6 was evaluated by sedimentation time, the conventional fiber was 3.7 minutes (Comparative Example 5) and the ultrafine fiber was 1.3 minutes (Comparative Example 6). Sedimentation occurred quickly and the dispersion stability was not good.

Example 10
Example of nanofiber combination lotion (1)
The following compounding agents were added to the nanofiber compound solution prepared in Example 6 to prepare a nanofiber-containing lotion. When the sensory evaluation when using lotion was performed on 10 subjects, the lotion using conventional fibers having a diameter of several tens of nanometers or ultrafine fibers of several μm as in Comparative Examples 7 and 8, There were 10 people in Comparative Example 7 who felt a rough feeling due to thick fibers when making up, and 9 people in Comparative Example 8, but in the case of nanofiber lotion, there was no sense of incongruity in the feeling of use in all subjects. It was natural. In addition, the nanofiber lotion also improved rough skin and prevented sunburn. Furthermore, it did not flow due to sweat and the makeup lasted well.

Nanofiber combination solution nanofiber of Example 6 86.5 wt%
Glycerin 5.0wt%
Allantoin 0.3wt%
Ethanol 8.0wt%
Ethyl parabenzoate 0.2wt%
Total 100.0wt%
Comparative Examples 7 and 8
Example of lotion containing conventional normal fiber and ultrafine fiber The following compounding agents were added to an aqueous solution of 27 μm diameter normal fiber and 2.1 μm diameter fine fiber prepared in Comparative Examples 2 and 4, and Comparative Example 7 and 8 lotions were prepared. Conventional fibers with a diameter of several tens of nanometers and ultrafine fibers with a diameter of several micrometers have a rough feeling due to the fibers when making up.

Aqueous solution of Comparative Example 2 (Comparative Example 7) 86.5 wt%
Aqueous solution of Comparative Example 4 (Comparative Example 8) 86.5 wt%
Glycerin 5.0wt%
Allanin 0.3wt%
Ethanol 8.0wt%
Ethyl parabenzoate 0.2wt%
Total 100.0wt%
Example 11
Example of nanofiber-containing lotion (2)
The nanofiber blended solution prepared in Example 5 and a commercially available lotion (The Skincare Hydrobalancing Softener made by Shiseido) were mixed at the following blending ratio for 3 minutes with a lab stirrer to prepare a nanofiber blended lotion. When 10 subjects were subjected to a sensory evaluation when using lotion, all the subjects felt that there was no sense of incongruity during use and a natural feeling. By blending nanofibers, the flow of makeup due to sweat could be prevented and the makeup lasting was improved. In addition, by blending nanofibers, the pore size is reduced by entanglement between nanofibers, so that the moisture retention is good and the moist feeling of the skin after use is improved.
Example 5 Nanofiber Mixing Solution 10wt%
The Skin Care Hydro Balancing Softener 90wt%
Total 100wt%
Example 12
Example of emulsion containing nanofiber (1)
The following compounding agent was added to the nanofiber compound solution prepared in Example 5 to prepare an emulsion. The blending method is as follows. First, nanofiber, lecithin, propylene glycol and pure water are added and stirred to obtain a liquid A. Next, the carboxyvinyl polymer is neutralized with a part of ethanolamine (0.4 wt%) to obtain a liquid B. Furthermore, oil components such as stearic acid, glyceryl monostearate, cetanol, liquid paraffin, and squalane are mixed at 80 ° C. to obtain liquid C. Add remaining ethanolamine (1.0 wt%) to Liquid A and mix at 80 ° C, then mix and emulsify Liquid C, then adjust the viscosity by adding Liquid B to obtain an emulsion containing nanofibers. It was. The nanofiber-containing emulsion was an emulsion with good uniform dispersibility and long-term stability. In addition, when 10 subjects were subjected to sensory evaluation when using the emulsion, all the subjects felt that there was no sense of incongruity on the skin during use and that they felt natural. The emulsion did not have rough skin, did not flow due to sweat, and had good makeup.

Nanofiber combination solution of Example 5 Nanofiber water 10.0 wt%
Triethanolamine 1.4wt%
Lecithin 0.2wt%
Propylene glycol 8.3wt%
Methyl parabenzoate 0.2wt%
1% carboxyvinyl polymer 20.0wt%
Stearic acid 2.6wt%
Glycerol monostearate 1.0wt%
Cetanol 1.0wt%
Liquid paraffin 8.0wt%
Squalane 1.0wt%
Pure water 46.3wt%
Total 100.0wt%
Example 13
Example of emulsion containing nanofiber (2)
The nanofiber blended solution prepared in Example 5 and a commercially available emulsion (The Skincare Night Essential Moisturizer manufactured by Shiseido Co., Ltd.) were mixed at the following blending ratio for 15 minutes with a lab stirrer to prepare a nanofiber emulsion. When 10 subjects were subjected to sensory evaluation when using the emulsion, it was found that all subjects had a natural feeling of use without feeling uncomfortable when using the emulsion. In addition, the nanofibers uniformly covered the skin surface, that is, the skin surface's sealing force improved the moist feeling of the skin after use. In addition, by blending nanofibers, it was possible to prevent the flow due to sweat and improve the makeup.

Example 5 Nanofiber Mixing Solution 10wt%
The Skincare Night Essential Moisturizer 90wt%
Total 100wt%
Example 14
Example of Nanofiber Blending Foundation The following Group A ingredients are mixed at 80 ° C. with a high-speed lab stirrer until uniform. Group B is also mixed at 80 ° C. with a low speed lab stirrer until uniform. A Group B compounding agent is mixed with Group A and emulsified. The nanofiber blend solution prepared in Example 4 was mixed with the emulsified liquid until uniform, and then cooled to obtain a nanofiber blend foundation. Sensory evaluation was performed on 10 subjects when using the foundation. In all subjects, there was no sense of incongruity during use, good slipping at the time of application, and familiarity with wrinkles and wrinkles on the skin. The adhesion of the foundation to the skin was also good. In addition, the feel at the time of use was also well balanced between the good breathability to the skin by the nanofibers and the moisture retention due to the sealing force by the multiple nanofibers. Further, the foundation had good makeup due to the effects of fiber adhesion, water retention, moisture retention, breathability and the like, and the resistance to flow caused by sweat was large.
The nanofiber combination solution of Example 4 10.0 wt%
Group A propylene glycol 5.0wt%
Butyl glycol 8.0wt%
Carboxyvinyl polymer 0.3wt%
Trietylamine 0.5wt%
Methylparaben 0.1wt%
Titanium oxide fine particles 6.0wt%
Talc 1.5wt%
Bengala 1.5wt%
Iron oxide 1.0wt%
Pure water 42.4wt%
Group B Stearic acid 2.6 wt%
Octyldodecyl myristate 10.0wt%
Cetanol 1.0wt%
Glycerol monostearate 2.0wt%
Liquid paraffin 6.0wt%
Squalane 2.0wt%
Propylene paraben 0.1wt%
Total 100.0wt%
Example 15
Example of nanofiber blended oily cream The following blending agent was added to the nanofiber blended solution prepared in Example 4 and mixed at 40 ° C. with a low-speed lab stirrer to prepare a nanofiber blended oily cream. Sensory evaluation when using an oil-based cream was performed on 10 subjects, and in all subjects, there was no sense of incongruity at the time of use, and slipping at the time of application was good and feel was good. . The cream had a moist feeling on the skin, no flow due to sweat, and good makeup.
The nanofiber combination solution of Example 4 10.0 wt%
Cetanol 5.0wt%
Lanolin 5.0wt%
Propyl myristate 10.0wt%
Liquid paraffin 27.0wt%
Vaseline 10.0wt%
Lipophilic surfactant 4.0wt%
Hydrophilic surfactant 4.0 wt%
Paraffin 1.0 wt%
Pure water 24.0wt%
Total 100.0wt%
Example 16
Example of nanofiber blended pack Add the following blending agent to the nanofiber gel after secondary beating produced in Example 1 and mix at 40 ° C. with a low-speed lab stirrer until uniform. Produced. When 10 patients were subjected to sensory evaluation when the pack was used, all subjects had no discomfort during use, good slipping during application, and good feel. In addition, the nanofibers in the pack also entered the wrinkle lines of the skin, and it was possible to remove dirt and fat components that were difficult to remove in the lines, which had a refreshing feeling and an effect of glossing the skin. In addition, after removing the dirt and fat, moisturizing the skin and supplying nutrients (addition of various nutrient components is possible) was effective in preventing rough skin and recovering the skin. Furthermore, it has moisturizing and water retaining effects on the entire skin, and moisturizes and moisturizes the skin. Moreover, when the pack which mix | blended was extract | collected to a small amount of glass slides and the titanium oxide microparticles | fine-particles whose average diameter is 0.02 micrometer were observed, there was no aggregation of titanium oxide and it was disperse | distributing finely.
Nanofiber gel-like material of Example 1 20.0 wt%
Propylene glycol 5.0wt%
Glycerin 5.0wt%
Bentonite 2.0wt%
Titanium oxide fine particles 1.0wt%
Pure water 67.0wt%
Total 100.0wt%
Example 17
Example of a method of directly beating nanofibers in an emulsion 1.6 g of nanofiber aggregate short fibers having a moisture content of 100% obtained in Example 1 (0.8 g when dried) were collected and used in Example 13. Add 499.5 g of a commercially available emulsion (made by Shiseido (The Skincare Hydrobalancing Softener)), (1) Disperse it at 6000 rpm for 5 minutes with a lab mixer, and (2) Obtain an emulsion filtered through a 50 mesh stainless steel wire mesh. It was. (3) The nanofibers on the stainless wire mesh were returned to the emulsion, and the operations (1) and (2) were repeated 7 times. By this operation, a nanofiber emulsion having a concentration of about 0.1 wt% was obtained. 10 g of the emulsion was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured to find that it was 0.12 wt%. Further, a commercially available emulsion was added to prepare a nanofiber emulsion having a concentration of 0.10 wt%.

As in Example 13, when 10 subjects were subjected to a sensory evaluation when using the emulsion, all the subjects felt that there was no sense of incongruity during use and a natural feeling. In addition, the sealing power of the nanofibers improved the moist feeling of the skin after use. In addition, by blending nanofibers, it was possible to prevent the flow due to sweat and improve the makeup.
Example 1 nanofiber (pure) 0.1 wt%
The Skincare Hydrobalancing Softener 99.9wt%
Total 100.0wt%
Examples 18 and 19
Example of Compounding Solution Combining Nanofibers with Organic Solvent Nanofiber aggregate short fibers obtained in Example 1 were dried at 50 ° C. for 12 hours, and 0.8 g of nanofibers after drying was added to the following solvent: It was added to 499.5 g of ethanol (Example 18) and toluene (Example 19), (1) directly mixed and dispersed in a solvent at 6000 rpm for 10 minutes in a lab mixer, and (2) filtered through a 50 mesh stainless wire mesh and organic. A solvent solution was obtained. (3) The nanofibers on the stainless wire mesh were returned to the organic solvent solution, and the operations (1) and (2) were repeated 7 times. By this operation, a blended solution in which about 0.1% concentration of nanofibers was blended in an organic solvent was obtained. 10 g of the solution was taken in a vat, the solvent was evaporated in a dryer, and the fiber concentration was measured and found to be 0.11 wt%. Furthermore, each organic solvent was added and the nanofiber mixing | blending solution of a 0.10 wt% density | concentration was adjusted. The nanofibers in the solution are well dispersed in an organic solvent, and the number average diameter of single fibers is 61 nm (Example 18) and 62 nm (Example 19), respectively. In all the examples, the concentration index Pb of the single fiber diameter is 64% (Example 18) and 63% (Example 19), respectively. It was found that nanofibers can be beaten similarly to the beating in water of Example 1.

The ethanol solution (Example 18) containing nanofibers can be used for cosmetics and paints, and the toluene solution (Example 19) containing nanofibers can be used for paints and adhesives.
Example 1 nanofiber (pure) 0.1 wt%
Ethanol (Example 18) 99.9 wt%
Toluene (Example 19) 99.9 wt%
Total 100.0wt%
Example 20
Solvent replacement example of nanofiber compound solution 200 g of a gel-like product obtained by dehydrating the nanofiber 10 wt% gel-like material prepared in Example 1 (water content 9 times = 900%) to a water content 1 time (100%) was collected, The solution was put into 800 g of ethanol and stirred at 6000 rpm for 15 minutes with a laboratory stirrer. This was desolvated to a solvent ratio of 1 (100%), re-introduced in about 8 times the amount of fiber ethanol, and stirred with a lab stirrer at 6000 rpm for 15 minutes. This operation was repeated five times to obtain 1000 g of a mixed solution in which the residual moisture content was 0.1 wt% or less and nanofibers were blended with ethanol (the residual moisture content in ethanol can be controlled by the number of solvent replacements depending on the application). . By this method, the solvent could be replaced from water to ethanol. This method is a method that enables solvent substitution while confirming the dispersion and aggregation state of nanofibers when the aggregation of nanofibers is likely to occur depending on the type of organic solvent used, and the compatibility with organic solvents is low This method is suitable for uniform dispersion of nanofibers.

Example 21
Example of nanofiber blended paint 300 g of nanofiber blended solution in which the solvent obtained in Example 19 is toluene and 300 g of a commercially available urethane-based paint in which the solvent is toluene are stirred with a lab kneader at 30 ° C. for 30 minutes at 120 rpm. A paint containing nanofibers was obtained. The obtained paint had good elongation when applied with a brush and was easy to apply. Moreover, the gloss of the coating after application was good, and the coated surface was smooth despite the addition of fibers.

Example 22
Example of nanofiber compound solution with dispersant added (1)
Using N6 used in Example 1, poly L lactic acid (optical purity 99.5% or more) having a weight average molecular weight of 120,000, a melt viscosity of 30 Pa · s (240 ° C., shear rate of 2432 sec ⁻¹ ), and a melting point of 170 ° C., N 6 The content was 20 wt%, the kneading temperature was 220 ° C., and melted and mixed in the same manner as in Example 1 to obtain a polymer alloy chip.

Here, the weight average molecular weight of poly L lactic acid was determined as follows. That is, THF (tetrahydrofuran) was mixed with the sample chloroform solution to obtain a measurement solution. This was measured at 25 ° C. using water permeation gel permeation chromatography (GPC) Waters 2690, and the weight average molecular weight was determined in terms of polystyrene. The melt viscosity of N6 used in Example 1 at a shear rate of 2432 sec ⁻¹ was 57 Pa · s. The melt viscosity of this poly L lactic acid at 215 ° C. and a shear rate of 1216 sec ⁻¹ was 86 Pa · s. Using the obtained polymer alloy tip, melt spinning was performed in the same manner as in Example 1 at a melting temperature of 230 ° C., a spinning temperature of 230 ° C. (a base surface temperature of 215 ° C.), and a spinning speed of 3200 m / min to obtain an undrawn yarn. .

The obtained undrawn yarn was drawn and heat-treated in the same manner as in Example 1 at a drawing temperature of 90 ° C., a draw ratio of 1.5 times, and a heat setting temperature of 130 ° C. to obtain polymer alloy fibers. This polymer alloy fiber was 70 dtex, 36 filament, the strength was 3.4 cN / dtex, the elongation was 38%, and U% = 0.7%. When the cross section of the obtained polymer alloy fiber was observed with a TEM, poly-L-lactic acid showed the sea-island structure with N6 being the island, and the number average diameter of the island component N6 was 55 nm. It was a polymer alloy fiber that was uniformly dispersed in the size. The polymer alloy fiber was crushed to form a crushed tow of about 130,000 dtex. At this time, the toe was restrained from falling apart during sea removal treatment by tying the outer circumference of the tow with a cotton thread and fixing it every 30 cm. Then, the cassette tension was adjusted so that the fiber density of the tow was 0.04 g / cm ^3, and the toe was set in the sea removal device of FIG. Then, this tow was treated with 98%, 3% sodium hydroxide for 2 hours to remove the poly-L lactic acid component as a sea component, and a tow composed of nanofibers was produced. When the cross section of the nanofiber tow obtained here was observed with a TEM, the area ratio of the nanofibers to the total fibers was 100%, the single fiber number average diameter φm was 60 nm, and Pa was 100%. This tow was cut into a fiber length of 0.2 mm with a guillotine cutter to obtain nanofiber short fibers.
About 20 liters of water and 30 g of the short fibers were put into a Niagara beater, and the fibers were first beaten for 10 minutes each. The freeness of the nanofiber subjected to the primary beating was 152. Water was removed from the fiber with a centrifugal separator to obtain 250 g of primary beating fiber having a fiber concentration of 12 wt%. This primary beating fiber was secondarily beaten for 10 minutes with a PFI beating apparatus, and then dehydrated to obtain 250 g of secondary beating fibers having a concentration of 10 wt% of nanofibers. The freeness of the nanofibers subjected to secondary beating was 32. In order to evaluate the shape of the nanofiber after the secondary beating, the secondary beating fiber with a concentration of 10 wt% is diluted with water, a 0.01 wt% nanofiber blending solution is prepared, and φm, Pa, and Pb are evaluated. As a result, φm was 58 nm, Pa was 100%, and Pb was 67%.

  Collect 1g of the 10wt% nanofibers obtained after the secondary beating, add 999g of water, (1) disperse with a lab mixer at 13900rpm for 5 minutes, and (2) obtain a solution filtered through a 50 mesh stainless steel wire mesh. It was. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated 5 times. By this operation, a nanofiber compound solution having a concentration of about 0.01 wt% was obtained. 10 g of the solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 0.01 wt%.

An anionic dispersant (Charol AN-103P: molecular weight 10000), the main component of which is manufactured by Daiichi Kogyo Seiyaku Co., Ltd., is the main component manufactured by Daiichi Kogyo Seiyaku Co., Ltd. It added so that it might become, and it stirred with the laboratory mixer, and obtained the nanofiber mixing | blending solution of Example 22. It was 740 minutes when the dispersion stability of the nanofiber in this compounding solution was evaluated by sedimentation time. Further, the transparency of this blended solution was 78%.

Examples 23 and 24
Example (2) of nanofiber blending solution to which dispersant was added Using the tow composed of nanofibers obtained in Example 22, nanofiber short fibers cut to a fiber length of 0.5 mm and a fiber length of 1 mm were obtained. In Example 23, nanofiber short fibers having a fiber length of 0.5 mm and in Example 24 having a fiber length of 1 mm were beaten in the same manner as in Example 22 to obtain secondary beaten fibers. The freeness of the nanofiber subjected to secondary beating was 43 in Example 23 and 58 in Example 24. Subsequently, the concentration of the solution was adjusted in the same manner as in Example 22, and a dispersant was added to obtain the nanofiber compound solutions of Examples 23 and 24, respectively.
When the dispersion stability of the nanofibers in this blended solution was evaluated by sedimentation time, it was 520 minutes in Example 23 and 410 minutes in Example 24. Moreover, when the transparency of this compound solution was evaluated, it was 70% in Example 23 and 68% in Example 24.

Examples 25 and 26
Example (3) of nanofiber compounded solution to which dispersant was added In Example 22, the additive concentration of the dispersant was set to 10 wt% in Example 25 and 0.01 wt% in Example 26 to obtain nanofiber compounded solutions, respectively. . When the dispersion stability of the nanofibers in this blended solution was evaluated by sedimentation time, it was 452 minutes in Example 25 and 627 minutes in Example 26. The transparency of each blended solution was 65% in Example 25 and 83% in Example 26.
Example 27

Example (4) of nanofiber combination solution with added dispersant
Mixing temperature of 20 wt% of polystyrene (co-PS) PBT having a melt viscosity of 120 Pa · s (262 ° C., 121.6 sec ⁻¹ ), a melting point of 225 ° C. and 22% copolymerized PBT and 2-ethylhexyl acrylate, and kneading temperature Was 240 ° C. and melt-kneaded in the same manner as in Example 1 to obtain a polymer alloy chip.

  This was melt-spun in the same manner as in Example 1 at a melting temperature of 260 ° C., a spinning temperature of 260 ° C. (die surface temperature of 245 ° C.), a single hole discharge rate of 1.0 g / min, and a spinning speed of 1200 m / min. The obtained undrawn yarn was drawn and heat-treated in the same manner as in Example 1 at a drawing temperature of 100 ° C., a draw ratio of 2.49 times, and a heat setting temperature of 115 ° C. The obtained drawn yarn was 161 dtex, 36 filaments, and the strength was 1.4 cN / dtex, the elongation was 33%, and U% = 2.0%. When the cross section of the obtained polymer alloy fiber was observed with TEM, co-PS showed the sea-island structure with the sea and copolymerized PET with the island, and the number average diameter of the copolymerized PET was 45 nm. As a result, nano-sized and uniformly dispersed polymer alloy fibers were obtained. By immersing this polymer alloy fiber in trichlene, 99% or more of the sea component co-PS was eluted and then dried, and cut into 0.5 mm with a guillotine cutter to obtain PBT nanofiber short fibers. . Secondary beating fibers were obtained from the cut fibers in the same manner as in Example 1. The fiber concentration of the PBT nanofiber after this secondary beating was 8 wt%, and the freeness was 96. In order to evaluate the form of the nanofiber after the secondary beating, the secondary beating fiber having a concentration of 10% wt is diluted with water to prepare a 0.01 wt% PBT nanofiber mixed solution, and evaluation of φm, Pa, and Pb As a result, φm was 52 nm, Pa was 100%, and Pb was 69%.

1.3 g of the obtained secondary beating fiber was collected, 998 g of water was added, (1) dispersed at 13900 rpm for 5 minutes with a laboratory mixer, and (2) a solution filtered through a 50 mesh stainless wire mesh was obtained. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated 5 times. By this operation, a PBT nanofiber combination solution having a concentration of about 0.01 wt% was obtained. 10 g of the solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 0.01 wt%.

A nonionic dispersant (Neugen EA-87: molecular weight 10,000) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was added to this nanofiber blended solution so that the concentration was 0.10 wt% with respect to the blended solution. The PBT nanofiber compound solution of Example 27 was obtained by stirring. It was 669 minutes when the dispersion stability of the nanofiber in this compounding solution was evaluated by sedimentation time. Further, the transparency of this blended solution was 81%.

Example 28
Example (5) of nanofiber combination solution with added dispersant
Example ^{1 with a} melt viscosity of 300 Pa · s (220 ° C., 121.6 sec ⁻¹ ), a PP (20 wt%) with a melting point of 162 ° C. and poly L lactic acid (80 wt%) of Example 22, and a kneading temperature of 220 ° C. In the same manner as above, melt kneading was performed to obtain a polymer alloy chip.

  This was melt-spun in the same manner as in Example 1 at a melting temperature of 220 ° C., a spinning temperature of 220 ° C. (die surface temperature of 205 ° C.), a single hole discharge rate of 2.0 g / min, and a spinning speed of 1200 m / min. The obtained undrawn yarn was drawn and heat treated in the same manner as in Example 1 at a drawing temperature of 90 ° C., a draw ratio of 2.0 times, and a heat setting temperature of 130 ° C. The obtained drawn yarn was 101 dtex, 12 filaments, and had a strength of 2.0 cN / dtex and an elongation of 47%.

  When a cross section of the obtained polymer alloy fiber was observed with a TEM, poly-L-lactic acid showed a sea-island structure with PP as an island, PP average diameter was 150 nm, PP was nano-sized and uniformly dispersed A polymer alloy fiber was obtained.

  By immersing the obtained polymer alloy fiber in a 3% aqueous sodium hydroxide solution at 98 ° C. for 2 hours, 99% or more of the poly L-lactic acid component in the polymer alloy fiber is hydrolyzed and neutralized with acetic acid. Then, it washed with water, dried, and cut | disconnected to 0.8 mm length with the guillotine cutter, and obtained PP nanofiber short fiber. Secondary beating fibers were obtained from these short fibers in the same manner as in Example 1. The fiber concentration of the PP nanofiber after this secondary beating was 6 wt%, and the freeness was 104. In order to evaluate the shape of the nanofiber after the secondary beating, the secondary beating fiber having a concentration of 10 wt% is diluted with water, a 0.01 wt% PP nanofiber mixed solution is prepared, and φm, Pa, and Pb are evaluated. As a result, φm was 154 nm, Pa was 100%, and Pb was 69%.

1.7 g of the obtained secondary beating fiber was collected, 998 g of water was added, (1) dispersed in a lab mixer at 13900 rpm for 5 minutes, and (2) a solution filtered through a 50-mesh stainless wire mesh was obtained. (3) The nanofibers on the stainless wire mesh were returned to water, and the operations (1) and (2) were repeated 5 times. By this operation, a PP nanofiber compound solution having a concentration of about 0.01 wt% was obtained. 10 g of the solution was taken in a vat, water was evaporated in a dryer, and the fiber concentration was measured and found to be 0.01 wt%.

A nonionic dispersant (Neugen EA-87: molecular weight 10,000) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was added to this nanofiber blended solution so that the concentration would be 0.10 wt% with respect to the blended solution, and stirred. A PP nanofiber compound solution of Example 27 was obtained. It was 597 minutes when the dispersion stability of the nanofiber in this compounding solution was evaluated by sedimentation time. Further, the transparency of this blended solution was 72%.

It is the schematic which shows an example of the spinning machine for "polymer alloy fiber" used as the raw yarn of nanofiber. 2 is a transmission electron microscope (TEM) photograph showing an example of the shape of an island in the cross section of the polymer alloy fiber of Example 1. FIG. It is the schematic of a casserole sea removal device.

Explanation of symbols

1: Hopper 2: Melting part 3: Spin block 4: Spin pack 5: Base 6: Chimney 7: Yarn 8: Focusing oiling guide 9: First take-up roller 10: Second take-up roller 11: Winder 12: Detachment Sea treatment tank 13: Seawater treatment liquid piping 14: Pump 15: Upper bar 16: Lower bar 17: Treatment liquid discharge hole 18: Dough-shaped tow 19: Seawater treatment liquid

Claims (17)

Polyester, polyamide, polyolefin, polyphenylene sulfide, phenol resin, polyvinyl alcohol, polysulfone, polyurethane, fluoropolymer and a thermoplastic polymer that is at least one selected from the group consisting of derivatives thereof . A blended solution comprising a fiber dispersion having a diameter of 1 to 500 nm and a sum Pa of the single fiber ratio of 60% or more, and a solvent. Polyester, polyamide, polyolefin, polyphenylene sulfide, phenol resin, polyvinyl alcohol, polysulfone, polyurethane, fluoropolymer and a thermoplastic polymer that is at least one selected from the group consisting of derivatives thereof . A blending solution comprising a fiber dispersion having a diameter of 1 to 200 nm and a sum Pa of the single fiber ratio of 60% or more, and a solvent. 3. The blend according to claim 1 or 2, wherein the concentration index Pb of single fiber diameters representing a ratio of fibers having a median diameter of single fibers by a number average and entering a width of 30 nm before and after that is 50% or more. solution. The solvent according to any one of claims 1 to 3, wherein the solvent is at least one selected from the group consisting of water, oil, and an organic solvent. The freezing degree of this fiber dispersion is 350 or less, The formulation solution in any one of Claims 1-4 characterized by the above-mentioned. Content of this fiber dispersion is 5 wt% or less, The formulation solution in any one of Claims 1-5 characterized by the above-mentioned. The blend solution according to any one of claims 1 to 6, wherein the fiber dispersion is composed of short fibers having a fiber length of 5 mm or less. A blending solution according to any one of claims 1 to 7 , comprising a dispersant. Content of this dispersing agent is 0.00001-20 wt%, The formulation solution of Claim 8 characterized by the above-mentioned. The mixed solution according to claim 8 or 9 , wherein the dispersant is at least one selected from the group of nonionic dispersants, anionic dispersants, and cationic dispersants. The blend solution according to claim 10 , wherein the fiber dispersion has a zeta potential in the range of −5 to +5 mV, and the dispersant is a nonionic dispersant. The blend solution according to claim 10 , wherein the fiber dispersion has a zeta potential of −100 mV or more and less than −5 mV, and the dispersant is an anionic dispersant. The blend solution according to claim 10 , wherein the fiber dispersion has a zeta potential of more than +5 mV and 100 mV or less, and the dispersant is a cationic dispersant. The compounding solution according to any one of claims 10 to 13 , wherein the dispersant has a molecular weight of 1,000 to 50,000. Claim 1-14 cosmetics made using compound solution of any one of. Coating made using a blend solution according to any of claims 1-14. The method for producing a blended solution according to any one of claims 1 to 14 , wherein the fiber assembly is directly beaten in at least one selected from the group consisting of water, oil and organic solvent.