The present invention relates to electrospun fibers comprising i) a hydrophilic polymer that is soluble in a first solvent, ii) a bioadhesive substance that is slightly soluble in said first solvent, iii) optionally, a drug substance.

A method for forming a coating on a skin surface using a nanofiber sheet, the method including: (1) applying to the skin a sheet transparentizing agent containing 2 mass % or more of one or more oil agent; and (2) transferring a white nanofiber sheet mainly composed of a water-insoluble polymer to the skin after (1), where the transferred white nanofiber sheet becomes transparent and the coating is a transparent coating through which the skin is visible.

A smokeless tobacco product includes smokeless tobacco and structural fibers. The structural fibers forming a network in which the smokeless tobacco is entangled. The structural fibers have a composition different from the smokeless tobacco. The tobacco-entangled fabric can have an overall oven volatiles content of at least 10 weight percent. In some embodiments, the structural fibers form a nonwoven network. In some embodiments, fibrous structures of the smokeless tobacco are entangled with the structural fibers.

A smokeless tobacco product includes smokeless tobacco and structural fibers. The structural fibers forming a network in which the smokeless tobacco is entangled. The structural fibers have a composition different from the smokeless tobacco. The tobacco-entangled fabric can have an overall oven volatiles content of at least 10 weight percent. In some embodiments, the structural fibers form a nonwoven network. In some embodiments, fibrous structures of the smokeless tobacco are entangled with the structural fibers.

One embodiment of the present invention provides a nonwoven fabric containing silk fibers in which an abs intensity ratio [abs (1650)/abs (1620)], which is a ratio of an intensity of a peak positioned in a vicinity of 1650 cm.sup.−1 [abs (1650)] in an infrared absorption spectrum to an intensity of a peak positioned in a vicinity of 1620 cm.sup.−1 [abs (1620)] in an infrared absorption spectrum, is larger than 0.65 and 1.90 or less, and a method for producing the nonwoven fabric containing silk fibers.

One embodiment of the present invention provides a nonwoven fabric containing silk fibers in which an abs intensity ratio [abs (1650)/abs (1620)], which is a ratio of an intensity of a peak positioned in a vicinity of 1650 cm.sup.−1 [abs (1650)] in an infrared absorption spectrum to an intensity of a peak positioned in a vicinity of 1620 cm.sup.−1 [abs (1620)] in an infrared absorption spectrum, is larger than 0.65 and 1.90 or less, and a method for producing the nonwoven fabric containing silk fibers.

The present invention provides nanometer-sized fibers that are produced by an electrospinning method with use of a spinning solution for electrospinning, said spinning solution being environmentally friendly and taking the effects of an organic solvent on the human body into consideration. The fibers are formed from a resin that contains a silicone-modified polyurethane resin which is a reaction product of (A) a polyol, (B) a water dispersant, (C) an active hydrogen group-containing organopolysiloxane represented by formula (1)

R.sup.1R.sup.2R.sup.3SiO(SiR.sup.2R.sup.3O).sub.nSiR.sup.1R.sup.2R.sup.3  (1)

(wherein R.sup.1 represents a monovalent hydrocarbon group which may have an oxygen atom in the chain, while having from 1 to 10 carbon atoms and a hydroxyl group or a mercapto group, or a monovalent hydrocarbon group which has a primary amino group or a secondary amino group, while having from 1 to 10 carbon atoms; each of R.sup.2 and R.sup.3 represents a group that is selected from among an alkyl group having from 1 to 10 carbon atoms, an aralkyl group having from 7 to 10 carbon atoms, an aryl group having from 6 to 12 carbon atoms and a vinyl group; and n represents an integer from 1 to 200), and (D) a polyisocyanate.

The present invention provides nanometer-sized fibers that are produced by an electrospinning method with use of a spinning solution for electrospinning, said spinning solution being environmentally friendly and taking the effects of an organic solvent on the human body into consideration. The fibers are formed from a resin that contains a silicone-modified polyurethane resin which is a reaction product of (A) a polyol, (B) a water dispersant, (C) an active hydrogen group-containing organopolysiloxane represented by formula (1)

R.sup.1R.sup.2R.sup.3SiO(SiR.sup.2R.sup.3O).sub.nSiR.sup.1R.sup.2R.sup.3  (1)

(wherein R.sup.1 represents a monovalent hydrocarbon group which may have an oxygen atom in the chain, while having from 1 to 10 carbon atoms and a hydroxyl group or a mercapto group, or a monovalent hydrocarbon group which has a primary amino group or a secondary amino group, while having from 1 to 10 carbon atoms; each of R.sup.2 and R.sup.3 represents a group that is selected from among an alkyl group having from 1 to 10 carbon atoms, an aralkyl group having from 7 to 10 carbon atoms, an aryl group having from 6 to 12 carbon atoms and a vinyl group; and n represents an integer from 1 to 200), and (D) a polyisocyanate.

A nonwoven fabric manufacturing facility includes a fiber assembly manufacturing step and a heating and drawing step. In the fiber assembly manufacturing step, fibers formed using an electrospinning method are collected to form a fiber assembly. In the heating and drawing step, the fiber assembly is drawn to form nonwoven fabric in a state where the fiber assembly is heated to a melting point of the fibers. In the formed nonwoven fabric, an average pore diameter is 15 μm or more, a relative standard deviation of a pore diameter distribution is 0.1 or less, and an average fiber diameter of the fibers is 3 μm or less.

A nonwoven fabric manufacturing facility includes a fiber assembly manufacturing step and a heating and drawing step. In the fiber assembly manufacturing step, fibers formed using an electrospinning method are collected to form a fiber assembly. In the heating and drawing step, the fiber assembly is drawn to form nonwoven fabric in a state where the fiber assembly is heated to a melting point of the fibers. In the formed nonwoven fabric, an average pore diameter is 15 μm or more, a relative standard deviation of a pore diameter distribution is 0.1 or less, and an average fiber diameter of the fibers is 3 μm or less.