JP2010194242A - Flap material for type of bag with flap - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flap material for a knapsack which has a feeling of smoothness and gloss on the surface, and sharpness in color, and that excels in bend resistance and in the effect of preventing a coloring agent applied to the rear surface from being transferred to the front surface when the rear and the front surface are superimposed and stored. <P>SOLUTION: In the flap material for the type of bag with a flap, a coloring layer is formed on the rear surface of a fiber base material layer, and on the opposite side to the rear surface, a polyurethane surface layer is laminated which contains binder polyurethane and polyurethane particulates of grain size of 1-50 μm in a mass ratio of 10-40 parts to 100 parts of the binder polyurethane. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cover-type bag cover material, and more particularly to a school bag cover material.

  Conventionally, in a cover-type lid cover material in which a resin surface layer is laminated on the surface of a fiber base material, in particular, in a cover-type cover-top cover material or a satchel cover material, printing on the back surface of the fiber base material, etc. There are many cases in which a design is applied and used as a covering material for a covering-type ridge or a school bag covering material without backing. As a typical example, a colored layer printed with a pattern represented by a check pattern or a tartan pattern is formed on the back surface of the cover material of the school bag. And the sheet for the cover material when the cover and the back surface of the cover-type bag and the back surface of the back cover are rolled up and the front and back surfaces are overlapped, or when the cover-type cover and bag are manufactured There is a problem that the printed pattern applied to the back surface is transferred to the front surface while the back cover is cut and cut into the shape of the cover material of the cover lid type bag or the backpack of the school bag. Yes, it impairs quality degradation and workability. In particular, the above problems occur frequently during high temperatures and humidity in the summer, so there is no effect on the surface of the printing ink applied to the back side of the covering lid bag or backpack covering material, which is not affected by storage conditions or the environment. There is a need for formula bags and school bag covers.

  Examples of a method for preventing transfer of ink printed on the back surface of the back cover material to the front surface include, for example, a method of forming a protective layer on the back surface after printing, a method of hardening the surface layer resin, and a surface layer There is a method of coating a silicone resin, a fluorine resin, or the like (for example, Patent Document 1). However, these methods have not been sufficient to prevent transfer of print ink. In addition, there are problems that increase the process and increase the cost, and the appearance, texture, surface touch, and bending resistance may be inferior.

Japanese Utility Model Publication No. 3-113618

  The problem to be solved by the present invention is a covering lid bag or a satchel covering material having smoothness and glossiness on the surface and clearness of color and excellent in bending resistance. When the front and back surfaces of the cover material of the school bag are overlapped, the coloring agent applied to the back surface is prevented from being transferred to the front surface side.

  As a result of intensive studies, the inventors of the present invention have found a cover-type ridge or a satchel cover material that solves the above problems, and have completed the present invention. That is, according to the present invention, a colored layer is formed on the back surface of the fiber base layer, and binder polyurethane and polyurethane fine particles having a particle diameter of 1 to 50 μm are added to 10 to 40 parts by weight of the binder polyurethane on the surface opposite to the back surface. It is a covering material of the covering lid type | mold with which the polyurethane surface layer containing a mass part is laminated | stacked. And it is preferable that a polyurethane porous layer exists between a polyurethane surface layer and a fiber base material layer, and it is preferable that the total thickness of a polyurethane porous layer and a polyurethane surface layer is 150 micrometers or more.

  The covering lid material of the covering lid type of the present invention and the covering material of the school bag have smoothness and glossiness of the surface, clearness of color, excellent bending resistance, and when the surface and the back surface are stacked and stored. Transfer of the colorant applied to the back surface to the front surface side can be suppressed.

Hereinafter, the present invention will be described in detail.
The fiber base layer of the present invention comprises a fiber assembly and an elastic polymer optionally impregnated. The fibers constituting the fiber assembly include ordinary fibers, for example, fibers made of synthetic resins such as polyester, polyamide, polyacrylonitrile, polyolefin, and polyvinyl alcohol, artificial fibers such as recycled cellulose, and natural fibers such as cotton, hemp, and wool. Examples thereof include fibers. Examples of the fiber assembly of the present invention include woven fabrics, knitted fabrics, non-woven fabrics, and laminated fabrics obtained by combining these fabrics. In the case of a synthetic fiber, not only a fiber composed of a single polymer but also a fiber obtained by mixing or spinning two or more polymers may be used. When mixed-spun fibers or composite-spun fibers are used, a method in which at least one polymer component constituting the fibers is extracted or removed at any stage in the fiber substrate manufacturing process, or fibers It is preferable that the fiber is made into a bundle of ultrafine fibers or a porous hollow fiber by a method of dividing into each polymer component constituting.
In the present invention, the fiber aggregate is preferably a nonwoven fabric that is bulky and has good cushioning and texture. As a method for producing the nonwoven fabric, a conventionally known method in which any one of the above-described fibers is used as a web and entangled by needle punching or high-speed fluid flow may be employed. Moreover, it can also be set as the laminated body of a nonwoven fabric and a knitted fabric. These nonwoven fabrics and these laminated fabrics are impregnated with an elastic polymer solution or dispersion as necessary. Prior to the impregnation treatment with the elastic polymer liquid, if necessary, the fiber assembly may be smoothed or densified by a treatment such as hot pressing. In addition, the fiber assembly surface is heated and pressed to prevent rupture of the fiber aggregate that is likely to occur during subsequent impregnation / solidification of the elastic polymer liquid and extraction or decomposition of the polymer constituting the mixed fiber or composite fiber. Alternatively, a method in which the constituent fibers are partially fused, or a method in which the fiber aggregate is impregnated and dried by water-soluble resin typified by polyvinyl alcohol and the fibers are glued and fixed may be used.

  Examples of the elastic polymer arbitrarily impregnated in the fiber assembly of the present invention include polyurethane polymers, polyacrylic acid polymers, polyvinyl chloride polymers, polyvinyl butyral polymers, polyamide polymers, polyamino acids. Examples thereof include at least one elastic polymer selected from a polymer, a silicone polymer, an acrylonitrile-butadiene copolymer, a styrene-butadiene copolymer, a mixture thereof, and a copolymer. Polyurethane is particularly preferable from the viewpoints of texture, durability, and adhesive strength between the fiber aggregate and the adjacent layer. The polyurethane includes at least one diol selected from polymer diols having a number average molecular weight of 500 to 2500, for example, polyester diol, polyether diol, polyester ether diol, polycaprolactone diol, polycarbonate diol, polyester polycarbonate diol; organic polyisocyanate For example, at least one kind selected from aromatic diisocyanate having a molecular weight of 500 or less, aromatic triisocyanate, alicyclic diisocyanate, aliphatic diisocyanate having a cyclic group, triphenylmethane-4,4,4-triisocyanate, etc. Organic polyisocyanates; and chain extenders such as low molecular diols, low molecular diamines, hydrazine and dicarboxylic acid dihydrazides Also one, polyurethane elastomers active hydrogen atoms obtained by reacting a molecular weight of 300 or lower molecular weight compound having at least two thereof. The raw material composition of polyurethane can be appropriately selected so as to satisfy various physical properties such as texture, deterioration resistance, yellowing resistance, and dyeability according to the requirements of the school bag covering material.

  If necessary, other polymers, various stabilizers, colorants, coagulation regulators and the like may be added to these elastic polymers. For example, the elastic polymer is impregnated into the fiber assembly as a solution or dispersion having a concentration of 3 to 40% by mass, and is immersed in an organic solvent (such as dimethylformamide) / water mixture at 10 to 80 ° C., 70 It is solidified by a wet method such as hot water treatment at -100 ° C., steam treatment at 100-200 ° C., or a dry method of dry heat treatment at 50-200 ° C. Examples of the solvent and the dispersion medium include dimethylformamide, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, methanol, isopropanol, ethyl cellosolve, butyl cellosolve, water and the like alone or in combination. As the coagulation method, the wet coagulation method is preferable in terms of texture. By using the wet coagulation method, the elastic polymer coagulates in a porous state, and a natural leather-like texture is obtained. The amount of the elastic polymer impregnated into the fiber assembly varies depending on the use, but the mass ratio of the fibers and the elastic polymer in the fiber base layer is 30:70 to 70: 30 is preferable.

  When the fiber assembly is composed of mixed spun fibers or composite spun fibers composed of two or more polymers, at least one of the fibers is formed before or after the fiber assembly is impregnated with the elastic polymer. Preferably, one polymer component is dissolved or decomposed away to form a fiber composed of at least one non-removed polymer component. For example, when the mixed spun fiber or the composite spun fiber is a fiber having a sea-island cross section, when the sea component polymer is dissolved or decomposed and removed, a fiber bundle of ultrafine fibers composed of the island component polymer is obtained. When dissolved and removed, a porous hollow fiber made of a sea component polymer and having many hollow portions in the fiber is obtained. When the fiber is a split type composite spun fiber in which a plurality of polymers are bonded in the length direction, the fibers are separated from each other by physical treatment or chemical treatment to obtain an ultrafine fiber bundle. It is done. Dissolution or decomposition removal, physical treatment, and chemical treatment for making the mixed spun fiber or composite spun fiber into ultrafine fiber bundles or porous hollow fibers can be performed under conditions known in the fiber technical field. Can be easily selected and determined.

  It is important that the covering material of the covering type bag of the present invention and the school bag covering material have a specific polyurethane surface layer formed on the surface opposite to the colored layer formed on the back surface of the fiber base material layer. However, it is preferable to insert a polyurethane porous layer between the fiber base layer and the polyurethane surface layer in order to improve the texture, cushioning properties and smoothness. As a method for forming the polyurethane porous layer, various conventionally known methods can be employed. For example, a polymer elastic dispersion, solution or melt is continuously applied to the substrate surface in an amount regulated by a certain clearance set between the fiber substrate layer surface and a knife, bar, roll, etc. Then, there is a method of drying in a film state by a dry method or coagulating and drying in a porous state, a method of coagulating and drying in a porous state by a wet method, or a method of forming a film by adding a foaming agent to the above-mentioned melt. Can be mentioned. Further, when the fiber base material is prepared, if a method is adopted in which the solidification of the elastic polymer impregnated into the fibrous base material and the solidification of the elastic polymer forming the polyurethane porous layer are completed at the same time, It can be dried once, and it is easy to obtain a sense of unity between the fiber base material and the coating layer (polyurethane porous layer and polyurethane surface layer) in the obtained cover material, so it is preferably used in the present invention. Is the method.

  The polyurethane porous layer is formed so that the total thickness with the polyurethane surface layer described later is 150 μm or more, preferably 170 μm. When the total thickness is less than 150 μm, the unevenness of the fiber base layer affects the smoothness of the covering lid surface, and it is difficult to obtain a satisfactory smooth feeling, particularly when finished in enamel or smooth tone. . There is no upper limit on the total thickness of the polyurethane surface layer and polyurethane porous layer, but if it is too thick, the flexibility becomes worse and the texture becomes harder. Since the mass of the material increases and the product becomes heavier than necessary, the upper limit is preferably 1 mm. Each of the polyurethane porous layer and the polyurethane surface layer is usually composed of one layer, but each may be composed of two or more layers.

  The polyurethane surface layer of the present invention contains 10 to 40 parts by mass of polyurethane fine particles having a particle diameter of 1 to 50 μm with respect to 100 parts by mass of polyurethane (binder polyurethane) constituting the polyurethane surface layer.

  Examples of the resin used for the binder polyurethane include polycarbonate-based polyurethane, polyester-based polyurethane, polyether-based polyurethane, modified products thereof, mixtures thereof, and copolymers. When long-term durability is required, polycarbonate-based polyurethane and mixed polyurethane mainly composed thereof are preferable, and non-yellowing polycarbonate-based polyurethane and mixed polyurethane mainly composed thereof are more preferable.

  A non-yellowing polycarbonate polyurethane is obtained by reacting a polycarbonate diol component, a non-yellowing diisocyanate component and a chain extender.

  Examples of the polycarbonate-based diol component include at least one polyalkylene polycarbonate diol having an average molecular weight of 500 to 5000 selected from polyethylene polycarbonate diol, polybutylene polycarbonate diol, polyhexamethylene polycarbonate diol, and the like; polydimethyl polycarbonate diol, polydiethyl polycarbonate At least one polydialkyl polycarbonate diol having an average molecular weight of 500 to 5000 selected from diols; at least one polyester polycarbonate diol having an average molecular weight of 500 to 5000 selected from polybutylene adipate polycarbonate diol, polyhexamethylene adipate polycarbonate diol, etc. Is mentioned.

  Examples of the non-yellowing diisocyanate component include aliphatic or alicyclic diisocyanates having a molecular weight of 500 or less, and at least one compound selected from isophorone diisocyanate, cyclohexyl diisocyanate, and dicyclohexylmethane diisocyanate is preferable. Further, as a part of the non-yellowing diisocyanate component, a small amount of tri- or higher functional non-yellowing polyisocyanate can be used as required.

  Examples of the chain extender include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, Aliphatic diols such as 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol , At least one active hydrogen selected from alicyclic diols such as cyclohexanedimethanol and cyclohexanediol, aliphatic diamines such as ethylenediamine and propylenediamine, alicyclic diamines such as isophoronediamine, hydrazine and dicarboxylic acid dihydrazide, etc. Molecular weight of 300 or more with at least 2 atoms They include low molecular weight compounds.

  In the present invention, a specific amount of polyurethane fine particles having a particle diameter of 1 to 50 μm is added to the binder polyurethane, and preferably the polyurethane fine particles are covered so that they are not exposed on the surface of the lid material, Surprisingly, the lid cover material and the school bag cover material when the cover material and the school bag cover material of the cover lid bag are overlapped and stored while maintaining the gloss and the clearness of the color. It has been found that the transfer of the printing ink formed as a colored layer on the back surface of the fiber base material constituting can be suppressed. As the polyurethane forming the fine particles, conventionally known polyurethanes, for example, polyurethanes such as polyesters, polyethers, polycarbonates and the like described above as examples of elastic polymers, and mixtures thereof can be used. Other thermoplastic elastomers such as polyester elastomer, polyamide elastomer, styrene elastomer, fluorine elastomer, polybutadiene elastomer, urethane / vinyl chloride elastomer, and ethylene copolymer may be blended with polyurethane. When forming the polyurethane surface layer, it is necessary to use a cross-linked polyurethane using a trifunctional or higher polyfunctional component as a part of a diisocyanate component or a chain extender as a reaction raw material of the polyurethane so as not to dissolve or swell in an organic solvent or the like. preferable. In order to prevent coloration (mainly yellowing) over time, it is preferable to use a non-yellowing polyurethane using the above-mentioned non-yellowing diisocyanate as a diisocyanate component which is a reaction material of polyurethane.

  The particle diameter of the polyurethane fine particles needs to be in the range of 1 to 50 μm, and preferably in the range of 3 to 30 μm. If it is smaller than 1 μm, the transfer prevention property of the ink formed as a colored layer on the back surface of the fiber base layer is insufficient, and if it is larger than 50 μm, it feels rough when touching the surface. Moreover, the compounding quantity of a polyurethane fine particle needs to be the range of 10-40 mass parts with respect to 100 mass parts of binder polyurethane, and the range of 12-35 mass parts is preferable. If it is less than 10 parts by mass, the ink transfer prevention property is insufficient. If it exceeds 40 parts by mass, the dispersibility, the bending resistance and the transparency in the binder polyurethane at the stage of forming the polyurethane surface layer will be poor, and it will tend to exist in a state close to exposure on the surface.

In the present invention, as described above, in order to obtain a covering lid material or a satchel covering material having a smooth surface and a glossy surface, the surface layer is formed in a state where the polyurethane fine particles are not exposed on the surface. It is preferable. The state in which the polyurethane fine particles are not exposed on the surface means that a part of each of the polyurethane fine particles is completely exposed, or even if not exposed, minute protrusions resulting from the shape of the polyurethane fine particles are substantially present on the surface of the polyurethane surface layer. It is a state that does not exist. More specifically, when an arbitrary portion of the polyurethane surface layer is observed with an electron microscope or the like, the number of exposures and protrusions is preferably 30 or less, more preferably 15 or less per 1 cm ² . That is. The polyurethane fine particles exposed on the surface are damaged when the surface of the object in contact with the surface is scratched by rubbing or the like, or when the surface is rubbed or scratched, the polyurethane fine particles fall off, and the removed part looks like scratches. The appearance is damaged. In addition, the light is irregularly reflected on the surface, resulting in problems such as a decrease in color sharpness and an inability to obtain the desired glossiness. Roughly and tactilely.

  The thickness of the polyurethane surface layer is preferably 5 μm or more, more preferably 10 μm or more from the viewpoint of abrasion resistance, although it depends on the particle diameter of the polyurethane fine particles to be blended. Although there is no upper limit to the thickness from the point of abrasion resistance, the total thickness of the polyurethane surface layer and the polyurethane porous layer is 150 μm to 1 mm as described above in consideration of the balance with the texture in addition to the flexibility described above. It is preferable that it is the range of these. In addition, it is preferable that the ratio of the thickness of a polyurethane surface layer and a polyurethane resin layer is 40: 60-3: 97.

The surface layer in a state where the polyurethane fine particles are not exposed on the surface is formed, for example, as follows. A coating liquid in which polyurethane fine particles are dispersed in a binder polyurethane solution (concentration: 20 to 60% by mass) is applied onto a release paper having a desired texture or a flat release paper, and the application surface is applied to the fiber base layer. After press-contacting on the formed polyurethane porous layer and solidifying and adhering, the release paper is removed. Examples of the solvent for the binder polyurethane solution include dimethylformamide, methyl ethyl ketone, toluene, xylene, methyl isobutyl ketone, methanol, isopropanol, ethyl cellosolve, and butyl cellosolve. Similarly, on the polyurethane surface layer formed on the release paper, the polyurethane to which the foaming agent is added is extruded from a T-die into a film state in a molten state, and pressed and solidified to form a polyurethane surface layer-polyurethane porous layer laminate. A method may be used in which the fiber base layer is bonded to the polyurethane porous layer and the release paper is removed. The fiber base layer may be bonded by a known bonding method using, for example, an adhesive after the polyurethane porous layer is solidified, or may be bonded while the porous layer is in a molten state.
The polyurethane that forms fine particles with the binder polyurethane preferably has the same composition, consists of the same type of structural unit, or consists of a chemically similar structural unit. Thereby, the adhesiveness and compatibility between the binder polyurethane and the polyurethane fine particles become extremely high, and the scratch resistance is improved.

  It is also possible to further improve the adhesiveness between the binder polyurethane and the polyurethane fine particles by adding a two-pack type urethane resin having a high crosslinking density containing a crosslinking urethane resin and a crosslinking agent to the binder polyurethane. In this case, it is necessary to select the addition amount of the cross-linking agent and the release paper while considering the ease of peeling between the polyurethane surface layer and the release paper. In addition, various additives such as a crosslinking accelerator, a colorant such as an organic pigment, a flame retardant, and an antioxidant can be added to the binder polyurethane. For applications where depth of color is required, a transparent or colored polyurethane intermediate layer may be provided between the surface layer and the porous layer in a range that does not interfere with the intended effect of the present invention. .

  The thicknesses of the polyurethane surface layer and the polyurethane porous layer in the covering lid material and the satchel covering material obtained as described above are as described above. Moreover, it is preferable that the thickness of a fiber base material layer is 1-3 mm.

Further, the covering material of the covering type lid and the school bag covering material of the present invention are the back surface of the fiber base material (the side on which the polyurethane surface layer is formed) of the obtained covering type lid material and the school bag covering material. The colored layer is formed on the opposite surface), and the colored layer can be formed by a conventionally known method.
For example, for applying a colored layer to the backside of the satchel cover material, such as a printed pattern consisting of a design represented by a solid, picture, character, line, abstract pattern, cloud pattern, check pattern, tartan pattern, etc. The print pattern is appropriately selected and printed on the back surface of the fiber base layer by a screen printing method, a gravure method or a spray method using a color ink represented by a pigment or a dye and made of a known colorant and a binder. Alternatively, a colored layer can be formed by printing on the back surface of the fiber base material by screen printing using a base paste for printing added with various dyes and pigments. An inkjet method using water-based ink is also common and is not particularly limited.
Moreover, the adhesion of the ink to the back surface of the fiber base layer may be continuous or discontinuous.
As the binder constituting the ink, a known resin can be used, and polyurethane and acrylic resin are preferable from the viewpoint of excellent mechanical properties, adhesiveness, and dispersibility of the colorant.
The thickness of the colored layer is not particularly limited, but is preferably 100 μm or less, and more preferably 50 μm or less, from the viewpoint that transferability due to physical pressure can be easily suppressed.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In addition, unless otherwise indicated, the part and% in an Example are related with mass. The evaluation of the school bag cover was performed by the following method.

(1) Appearance The color and glossiness of the surface of the satchel cover material were visually judged by the following criteria by five panelists engaged in the manufacture of the satchel selected arbitrarily.
A: The surface color is vivid, glossy, and luxurious.
C: The surface color is not clear and the gloss is also lost.
(2) Smoothness and feel The sensory evaluation of the smoothness and feel of the surface of the satchel cover material was conducted by the following criteria by five panelists engaged in the sale of an arbitrarily selected satchel.
A: Smooth and free from surface roughness.
C: There is no smoothness and the surface is rough.
(3) Bending resistance In accordance with JIS K 6545-1994, in a 20 ° C. and 65% RH environment, using a Bally Flexometer, the surface of one end of the measuring piece measuring 70 mm in length and 45 mm in width is inward. Bending with the end surface facing outward, attaching both ends of the measurement piece to the clamp, one clamp fixed, the other clamp bent the measurement piece by reciprocating motion, and occurred on the measurement piece every 50,000 times The damage was observed and the number of times until cracking occurred was measured.
(4) Transfer state of the color of the back of the cover material to the front surface Cut the cover material with the colored layer on the back surface into a square of 5 cm square, and stack the same cover material so that the back surface and the surface overlap. After sandwiching between two acrylic plates, applying a pressure load of 2 kg and leaving it in a dryer at 90 ° C. for 10 hours, the surface state of the cover material was observed and evaluated according to the following criteria.
A: No change is observed on the surface of all samples.
B: The color of the ink on the back surface is transferred to a part of the sample.
C: The color of the ink on the back surface has shifted to more than half of the sample.

Example 1
A sea-island composite fiber consisting of 45 parts of 6-nylon (sea component) and 55 parts of polystyrene (island component) was obtained by melt spinning. This was stretched 3 times, a fiber oil agent was applied, and after mechanical crimping, it was dried. The obtained crimped fiber was cut into 51 mm to form a 3 dtex staple, and after forming a web, needle punching of about 500 punch / cm ² was performed alternately from both sides to obtain an entangled nonwoven fabric. The basis weight of this entangled nonwoven fabric was 350 g / m ² and the apparent specific gravity was 0.17. This entangled nonwoven fabric was treated with a 4% aqueous solution of polyvinyl alcohol, the thickness was compressed and fixed to about 1.3 mm, and the surface was smoothed by buffing. This was impregnated with a dimethylformamide (hereinafter referred to as DMF) solution of polyurethane mainly composed of 13% concentration polyester-based polyurethane. Further, the same polyurethane elastomer solution was applied to the surface in an amount of 100 g / m ² in solid content, and then immersed in a DMF / water mixture to wet-coagulate the polyurethane in a porous state, and then in hot toluene. By eluting and removing the island components, the composite fiber was converted into a hollow fiber to obtain a fiber substrate layer having a polyurethane porous layer. According to microscopic observation, the thickness of the polyurethane porous layer existing above the nonwoven fabric layer of the fiber base material was 300 μm.

A non-yellowing polycarbonate-based polyurethane solution containing non-yellowing polyurethane fine particles (particle size: 15 μm, “Dynamic Bead 7150” manufactured by Dainichi Seika Kogyo Co., Ltd.) on a release paper (DE-125 manufactured by Dai Nippon Printing Co., Ltd.) Resin content 25%) 100 parts by mass (polyurethane fine particle content: 24 parts by mass with respect to 100 parts by mass of solid content of the non-yellowing polycarbonate polyurethane solution), Rezamin DUT4790 black (manufactured by Dainichi Seika Kogyo Co., Ltd.) 20 parts by mass A solution containing 30 parts by mass of DMF and 30 parts by mass of methyl ethyl ketone was applied so that the thickness after drying was 15 μm and dried to obtain a polyurethane outermost layer.
On the outermost polyurethane layer obtained, a DMF solution containing 100 parts by mass of one-component polyether polyurethane (Resamine ME8116 manufactured by Dainichi Seika Kogyo Co., Ltd.) and 20 parts by mass of Rezamin DUT4790 black is dried to a thickness of 20 μm. This was applied and dried to form a polyurethane intermediate layer.
Furthermore, on the intermediate layer, 100 parts by mass of a crosslinkable polyurethane adhesive solution composition UD8310 (Daiichi Seika Kogyo Co., Ltd.), 10 parts by mass of D-110N (Takeda Pharmaceutical Co., Ltd.), 5 parts of DMF, 10 ethyl acetate A polyurethane-based adhesive solution consisting of parts by mass was applied at 240 g / m ² (pure content 130 g / m ² ), and the polyurethane surface layer was dried for 15 seconds at 70 ° C. Pasted with quality layer. After that, after pressing with a roll with a clearance of 65% of the total thickness of the polyurethane porous layer and the fiber base layer, dried at 130 ° C. for 3 minutes, aged at 50 ° C. for 3 days, and then released from the release paper. Peeling school bag cover sheet was obtained. As a result of checking the surface of the satchel cover material sheet with an electron microscope, the polyurethane fine particles were not exposed on the surface.
Furthermore, a polyester system containing 10% by mass of a yellow pigment in solid content ratio with respect to polyurethane on the back surface (surface opposite to the surface on which the polyurethane porous layer is formed) of the fiber base material layer of the school bag covering cover material sheet. An ink made of a 10% polyurethane DMF solution was prepared, and a check pattern design was printed by a screen printing method to form a colored layer having a thickness of 3 μm on the back surface.

  The obtained satchel cover material was glossy and clear in color, polyurethane fine particles were not exposed on the surface, and the crease and texture were good. Each evaluation result is shown in Table 1.

Example 2
A sea-island composite fiber consisting of 45 parts of 6-nylon (sea component) and 55 parts of polystyrene (island component) was obtained by melt spinning. This was stretched 3 times, a fiber oil agent was applied, and after mechanical crimping, it was dried. The obtained crimped fiber was cut into 51 mm to form a 3 dtex staple, and after forming a web, needle punching of about 500 punch / cm ² was performed alternately from both sides to obtain an entangled nonwoven fabric. The basis weight of this entangled nonwoven fabric was 350 g / m ² and the apparent specific gravity was 0.17. This entangled nonwoven fabric was treated with a 4% aqueous solution of polyvinyl alcohol, the thickness was compressed and fixed to about 1.3 mm, and the surface was smoothed by buffing. This was impregnated with a polyurethane DMF solution mainly composed of 13% polyester polyurethane. Next, after the polyurethane is wet-solidified in a DMF / water mixture to make it porous, the island components are eluted and removed in hot toluene to convert the composite fibers into hollow fibers, thereby obtaining a fiber base layer. It was.

A non-yellowing polycarbonate-based polyurethane solution containing non-yellowing polyurethane fine particles (particle size: 15 μm, “Dynamic Bead 7150” manufactured by Dainichi Seika Kogyo Co., Ltd.) on a release paper (DE-125 manufactured by Dai Nippon Printing Co., Ltd.) Resin content 25%) 100 parts by mass (polyurethane fine particle content: 24 parts with respect to 100 parts by mass of solid content of the non-yellowing polycarbonate polyurethane solution), Rezamin DUT4790 black (manufactured by Dainichi Seika Kogyo Co., Ltd.), 20 parts by mass, A solution containing 30 parts by mass of DMF and 30 parts by mass of methyl ethyl ketone was applied so that the thickness after drying was 15 μm and dried to obtain a polyurethane outermost layer.
On the outermost polyurethane layer obtained, a DMF solution containing 100 parts by mass of one-component polyether polyurethane (Resamine ME8116 manufactured by Dainichi Seika Kogyo Co., Ltd.) and 20 parts by mass of Rezamin DUT4790 black is dried to a thickness of 20 μm. This was applied and dried to form a polyurethane intermediate layer.

Separately, 3-methyl-1,5-pentanediol, polyester diol obtained from adipic acid, butanediol, and 4,4′-diphenylmethane diisocyanate are mainly used for insertion between the polyurethane intermediate layer and the fiber base layer. A mixture of 100 parts by mass of polyester polyurethane pellets (Kuraray Co., Ltd. Kuramylon U-3190) as a component and 3 parts of black pigment pellets (polyethylene with a pigment concentration of 30%) was prepared. The mixture was extruded from a T-die of an extruder at a melting zone temperature of 210 ° C. and a die introduction part temperature of 210 ° C., and a 180 μm thick molten film was fed between the polyurethane intermediate layer and the fibrous base material. The obtained laminate was pressed with a metal roll and an elastic roll and cooled, and then the release paper was removed to obtain a school bag cover sheet.
Further, a tartan pattern was printed on the back surface by the same ink and printing method as in Example 1 to form a colored layer.

  The obtained satchel cover material was glossy and clear in color, polyurethane fine particles were not exposed on the surface, and the crease and texture were good. The evaluation results are shown in Table 1.

Comparative Example 1
A school bag cover sheet was produced in the same manner as in Example 1 except that the polyurethane fine particles were not used for the outermost layer, and a check pattern was printed in the same manner as in Example 1. Each evaluation result is shown in Table 1.

Comparative Example 2
A school bag cover material is produced in the same manner as in Example 1 except that the outermost layer does not use polyurethane fine particles and the polyurethane constituting the outermost layer is made of silicone-modified polyurethane. A check pattern was printed. Each evaluation result is shown in Table 1.

  The cover-type lid cover material and the school bag cover material obtained by the present invention have a smooth surface and glossy surface, a clear color feeling, excellent bending resistance, and the back surface when stored in a stacked state. The transfer of the printing ink applied to the surface of the cover is suppressed, and it is suitable for parts of cover-cover type ridges and cover materials of school bags.

Claims (4)

  A polyurethane surface layer in which a colored layer is formed on the back surface of the fiber substrate layer, and 10 to 40 parts by mass of binder polyurethane and polyurethane fine particles having a particle diameter of 1 to 50 μm are formed on the surface opposite to the back surface with respect to 100 parts by mass of the binder polyurethane. A cover-type lid covering material with a laminated structure.   The covering lid material for covering lid type | molds of Claim 1 in which a polyurethane porous layer exists between a polyurethane surface layer and a fiber base material layer.   The covering lid material for covering lids according to claim 1 or 2, wherein the total thickness of the polyurethane porous layer and the polyurethane surface layer is 150 µm or more.   The school bag using the covering material of any one of Claims 1-3.