JP2545000Y2 - Back of school bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the back of schoolbags for schoolchildren having a smooth texture that absorbs sweat of natural leather, and has excellent sweat absorption and surface strength.

[Conventional technology]

Conventionally, synthetic leather, artificial leather,
Natural leather and the like are used. A backpack of a backpack made of a leather-like sheet such as synthetic leather or artificial leather is made of a polyurethane resin, a polyacryl resin, a polyethylene resin, or the like as a surface resin layer of the constituent leather-like sheet. These backing materials had a profound feeling and depth of color, but were inferior to the smooth texture and sweat absorption of natural leather.

On the other hand, many attempts have been made to reproduce natural leather-like appearance and texture by mixing natural leather powder or collagen into the coating layer of the leather-like sheet. For example, Japanese Patent Publication 63-2364
No. 4, JP-B-63-315677, and the like. However, these leather-like sheets are merely mixed with a large-diameter leather powder or collagen powder, and the surface has a rough feeling, and a smooth or natural touch similar to natural leather cannot be obtained. . In addition, since the apparent bulk density of the collagen powder is as high as 0.3 g / cm ³ or more, it is inferior in sweat-absorbing property, and a smooth texture cannot be obtained. Furthermore, Tokiko Sho 61
Japanese Patent No. 163850 proposes a sheet material to which collagen powder is added, but the collagen powder used here has a short fiber form, so that it has poor compatibility with polyurethane, easily causes poor dispersion, and easily absorbs sweat. It is easy to produce spots on the skin and is also poor in sweat absorption.

[Problems to be solved by the invention]

An object of the present invention is to provide a back of a school bag that has a smooth texture that absorbs sweat of natural leather, and has excellent sweat absorption and surface strength.

[Means for solving the problem]

The present invention provides a leather-like sheet having a coating layer mainly composed of an elastic polymer on the surface of a fibrous base layer, wherein the surface of the coating layer is non-fibrous, has an average particle size of 10 μm or less, and has an apparent bulk density of 0.1.
The back of a school bag, comprising a mixture of collagen powder of about 0.3 g / cm ³ and a polymer mainly composed of polyurethane.

The fibrous base material layer having the coating layer of the present invention is made of ordinary fibers, for example, synthetic fibers such as polyester, polyamide, polyacrylonitrile, polyolefin, and polyvinyl alcohol, synthetic fibers such as regenerated cellulose, natural fibers, and fibers in special forms. For example, it is composed of fibers selected from ultrafine fibers such as polyester, polyamide and polyacrylonitrile or multicomponent fibers which can be transformed into ultrafine fiber bundle fibers or special porous fibers by dissolving and removing at least one component. One type of fabric selected from fiber entangled nonwoven fabric, fiber napped woven fabric, laminated fabric of nonwoven fabric and woven fabric, entangled by needle punch or high-speed fluid flow, and polyurethane, acrylic polymer, acrylonitrile・ Butadiene copolymer, styrene / butadiene copolymer Impregnating with an impregnating composition mainly composed of at least one kind of elastic polymer selected from the group of elastic polymers such as synthetic rubbers, and then, if necessary, applying a polymer coating composition and applying weight. Coagulated into a sponge structure in the combined solvent to transform the multicomponent fibers into ultrafine fiber bundles or special porous fibers, and if necessary, a polymer coating layer mainly composed of an elastic polymer was applied. It is a sheet-like material having a base layer made of a polymer mainly composed of an elastic polymer and a fiber assembly and a porous or non-porous coating layer of a polymer mainly composed of an elastic polymer on the surface thereof.

The collagen used for the surface layer in the present invention is obtained by treating and purifying animal skin, bones and tendons with an enzyme or the like, extracting polymeric collagen fibers, causing a cross-linking reaction between the collagen fibers, and then pulverizing. Average particle size 2-10μ, JIS K 6721
By a collagen powder of the non-fibrous apparent bulk density of 0.1 to 0.3 g / cm ³ as determined, for example, manufactured by Showa Denko of CX240 and CX2
60 and the like. When the average particle size of the collagen is larger than 10 μm, the surface becomes rough and a fine smooth surface cannot be obtained, and a natural leather-like smooth and natural touch cannot be obtained. Moreover, when the apparent density is more than 0.3 g / cm ^3, affinity decreased film strength of the resin because the bulkiness decreases collagen particles is reduced, the durability is lowered further, moisture and sweat The ability to inhale water decreases, and the desired sweat absorption property cannot be obtained. In addition, apparent bulk density
If it is less than 0.1 g / cm ³ , the strength of the collagen particles will be low and the coating film strength will be low.

The weight ratio of the collagen powder to the polyurethane-based polymer is in the range of 1: 2 to 1: 1. If the amount of the collagen powder is small, the characteristic of collagen such as sweat absorption and a smooth touch cannot be obtained, and if the amount of collagen is large, the collagen powder cannot be sufficiently fixed by the polymer, and the film strength is reduced. The texture also worsens.

In the present invention, the polyurethane mixed with the collagen powder is a polymer diol having an average molecular weight of 500 to 2500, for example, at least one selected from the group of polyester diol, polyether diol, polyester ether diol, polycaprolactone diol, polycarbonate diol and the like. And a polymer diol of an organic polyisocyanate such as an aromatic diisocyanate, an aromatic triisocyanate, an alicyclic diisocyanate, an aliphatic diisocyanate having a cyclic group, and triphenylmethane
Polyurethane obtained by reacting at least one organic polyisocyanate selected from the group of 4,4 ', 4 "-triisocyanate with a low molecular compound having at least two active hydrogen atoms as a chain extender. .

A polymer composition mainly composed of collagen and polyurethane is applied to the surface as a dispersion in which collagen powder is dispersed in a polymer solution. If necessary, a colorant such as a dye or a pigment, a stabilizer, an antistatic agent, a leveling agent and the like may be added to the coating solution. Further, it is also preferable to add an antibacterial agent and a deodorant to impart deodorant antibacterial properties simultaneously or by post-processing. As a method of applying the coating liquid, for example, the coating is performed by a method such as a roll coating method, a spray coating method, a surface contact method, or the like, which uses a roll such as a notched roll or a smooth surface roll. A preferred coating method is a roll coating method from the viewpoint of coating uniformity.

The coating amount, 5 to 50 g / m ² by weight of dry collagen,
Preferably in the range of 5 to 30 g / m ^2. If the amount of collagen applied is less than 5 g / m ² , the entire surface is not covered with the collagen powder, so that the entire surface does not have a fine matte surface and a smooth touch cannot be obtained. When the amount of collagen applied is large, the appearance does not deteriorate so much, but roughness appears and the film strength decreases, resulting in poor durability.

The surface provided with the polymer composition mainly composed of collagen and polyurethane has fine irregularities substantially equal to the size of collagen particles. The light is scattered by the fine irregularities, and the appearance becomes a matte appearance without glare. Collagen particles are not completely covered by the polymer, and many of the collagen particles are directly exposed to the surface. The leather-like sheet of the present invention can be colored with a pigment, but it is preferable to dye the leather-like sheet because the color has more depth. The dyeing method uses a metal complex salt dye, an acid dye, a disperse dye, or the like, and dyes it by a Wins dyeing method, a Jigger dyeing method, or the like.

The leather-like sheet obtained by the present invention has good sweat absorption,
It has the smooth texture of natural leather and the smooth and natural touch similar to natural leather without the slimy feel and has a profound feeling and depth of color, resulting in a leather-like sheet with excellent surface strength.

〔Example〕

Next, embodiments of the present invention will be described with reference to specific examples, but the present invention is not limited to these examples.
The parts and percentages in the examples relate to weight unless otherwise specified.

Example 1 As a base sheet, a 20% dimethylformamide (DMF) solution of a polyethylene adipate-based polyurethane containing a beige-based colorant was added to an entangled nonwoven fabric of multicomponent fibers containing polyethylene terephthalate as a dispersion component and polyethylene as a dispersion medium component. impregnated, and further the amount applied of 150 g / m ² on the surface
A sheet having a polyurethane microporous coating layer on one surface of a base layer in which polyurethane is contained in a porous state in a nonwoven fabric of ultrafine fiber bundle fibers obtained by dissolving and removing polyethylene after coagulation in a 40% DMF aqueous solution. Was. A polyethylene adipate-based polyurethane (10
%), Beige pigment, and DMF / acetone composed of a light stabilizer =
1/1 solution by gravure roll roll coating method 1
After applying 00 g / m ^2, 5 parts of an average particle size was added to 100 parts of a 30% DMF / acetone = 1/1 solution of polyethylene adipate polyurethane.
m, a composition liquid containing 30 parts of collagen powder having an apparent bulk density of 0.25 g / cm ³ was applied at 40 g / m ² by a roll coating method using a gravure roll, and dried. Next, heating embossing was performed at a temperature of 150 ° C. to finish a leather-like sheet.

The obtained leather-like sheet has a soft texture, has a good sweat-absorbing property, has a smooth texture similar to natural leather and a smooth and natural touch with no slimy feeling, and has a visual appearance. It was a backing material for a school bag with a profound feeling.

A backpack was made using this leather-like sheet on the back and back of the backpack, and the backpack was worn and found to be non-sticky even with sweat and had a smooth feel.

Example 2 A 20% DMF solution of a polyethylene adipate-based polyurethane containing a beige colorant was impregnated into an entangled nonwoven fabric of multicomponent fibers containing polyethylene terephthalate as a dispersion component and polyethylene as a dispersion medium component. After coagulation, polyethylene was dissolved and removed to obtain a substrate layer in which polyurethane was contained in a porous state in a nonwoven fabric of ultrafine fiber bundle-like fibers.

On a release paper, 30% DMF / methyl ethyl ketone (MEK) of polyester polyurethane = 100 parts of 1/1 solution with an average particle size of 5
μm, a composition liquid containing 20 parts of collagen powder having an apparent bulk density of 0.25 g / cm ³ and 20 parts of a beige pigment was applied at 40 g / m ² and dried, and then a DMF / MEK solution of a polyurethane adhesive was applied. Were laminated to obtain a leather-like sheet.

The obtained leather-like sheet has a soft texture, good sweat absorption, a smooth texture similar to natural leather, a smooth and natural touch with no slimy feel, and a surface strength. It was an excellent backing material for school bags.

A backpack was made using this leather-like sheet on the back and back of the backpack, and the backpack was worn and found to be non-sticky even with sweat and had a smooth feel.

Comparative Example 1 A leather-like sheet was obtained in the same manner as in Example 2 except that collagen powder was not added to the polyurethane solution.

The obtained leather-like sheet had a sticky feeling on the surface, lacked perspiration, and had low surface strength.

Create a school bag using this leather-like sheet on the back,
When I wore it, my back was sticky and sweaty.

[Effect of the invention]

Since the backpack using the back of the present invention has excellent sweat absorption properties, it can be worn comfortably for a long time without stickiness or stuffiness even if the back is sweated.

[Brief description of the drawings]

FIG. 1 is a perspective view of a school bag using the back of the present invention. In the figure, reference numeral 1 denotes the back.

Claims (1)

(57) [Scope of request for utility model registration] 1. A leather-like sheet having a coating layer mainly composed of an elastic polymer on the surface of a fibrous base layer, wherein the surface of the coating layer is non-fibrous, has an average particle size of 10 μm or less, and has an apparent bulk density of 0.1. ~
The back of a school bag, comprising a mixture of 0.3 g / cm ³ collagen powder and a polymer mainly composed of polyurethane.