JP4620603B2 - Inkjet printing substrate - Google Patents

Description

  The present invention relates to a substrate for printing made of a nonwoven fabric that is excellent in flexibility and light weight, but also excellent in water resistance and durability, and particularly relates to an inkjet printing substrate that enables clear image formation.

  Conventionally, non-woven fabric-based printing substrates have features such as better water resistance, softer texture, and more fabric-like texture than those based on paper. Taking advantage of this, it is used for applications such as calendars, candy packaging bags and handbags for offset printing, and for futon bags and kotatsu cover materials for gravure printing. However, as a printing substrate for announcements used outdoors, for example, for product advertisements, road guides, or banners for advertisements, it is excellent in flexibility and light weight while being water resistant and durable. Excellent base materials are required. Further, there is a demand for high quality materials with clearer printing characteristics.

  As such a printing substrate, for example, in Patent Document 1, an inkjet recording sheet obtained by coating or impregnating an ink receiving component on a support, the support is made of a nonwoven fabric, and the nonwoven fabric has a fiber diameter of 0. An ink jet recording sheet characterized by being composed of fibers having a denier of 1 to 0.8 denier is described. In addition, the nonwoven fabric as the support is a wet nonwoven fabric, or a stitch-bond method, a spunbond method, a melt-blown method, a dry-type nonwoven fabric by a thermal bond method, or a spunlace nonwoven fabric using a wet-type nonwoven fabric or a dry-type nonwoven fabric, A spunlace nonwoven fabric using a wet nonwoven fabric or a wet nonwoven fabric is used.

  Thus, in patent document 1, since the fiber used is a 0.1-0.5 denier extra fine fiber or a 0.5-0.8 denier fine fiber, there exists an effect that it is excellent in printability. However, only the wet nonwoven fabric or the melt blown nonwoven fabric can be applied to the ultrafine fiber. Among these, the wet nonwoven fabric has a very small fiber length, for example, 3 mm in the embodiment, and the strength of the resulting nonwoven fabric is extremely small. There was a problem of poor durability. In addition, the meltblown nonwoven fabric has a long fiber length, but the fibers are not stretched. Therefore, there is a problem that the strength of the resulting nonwoven fabric is extremely small and the durability is poor. On the other hand, for nonwoven fabrics such as a stitch bond method, a spun bond method, and a dry method using a card machine using a fine fiber having a fiber length of, for example, 15 mm or more, as a base material for inkjet printing, even if strength can be secured to some extent, Since the fiber is thick, the dispersibility of the fiber is inferior, the partial mass variation becomes large, and there is a problem that clear printing cannot be performed.

In Patent Document 1, the spunlace nonwoven fabric is a post-processing for achieving a specific fragile air permeability to improve printing characteristics, or a specific fragile air flow by being laminated and integrated with a fabric by three-dimensional entanglement. The printing characteristics are improved by achieving the degree. Therefore, the spunlace nonwoven fabric does not solve the essential problems such as the above-described durability and mass variation when using ultrafine fibers or fine fibers. Moreover, in patent document 1, polyvinyl alcohol was used as the adhesive agent between fibers, and it was inferior also in water resistance.

JP 2000-296670 A

  The present invention solves the above problems, and is a printing substrate made of a nonwoven fabric excellent in water resistance and durability while being excellent in flexibility and light weight, and enables a clear printed image formation. An object of the present invention is to provide a substrate for inkjet printing.

Means for solving the problems of the present invention is a printing substrate for forming an ink-jet printed image in which a nonwoven fabric containing ultrafine fibers generated by splitting from splittable fibers by the action of water flow has an ink receiving layer. There,
The non-woven fabric is formed by the spunbond method, and the splittable long fibers in the fiber web are formed by the action of a water flow sprayed from a nozzle head containing high-pressure water on a fiber web made of continuous splittable long fibers. Is a non-woven fabric formed only by a process in which ultrafine fibers with a fiber diameter of 0.1 to 10 μm are generated and the ultrafine fibers are entangled with each other,
The splittable long fiber is a fiber having a fiber diameter of 10 to 100 μm composed of a composite fiber that can be split by the action of water flow, and a fiber-forming polyester resin component and a polyamide resin component are combined. The ultrafine fiber is a polyester. A base material for ink jet printing comprising a base fiber and a polyamide fiber.

  According to the present invention, there is provided a printing substrate made of a nonwoven fabric that is excellent in flexibility and light weight, but also excellent in water resistance and durability, and is a substrate for inkjet printing that enables a clear printed image formation. It became possible to provide.

  In the substrate for inkjet printing of the present invention, a nonwoven fabric (hereinafter sometimes referred to as a nonwoven fabric base fabric) containing ultrafine fibers generated by splitting from splittable fibers by the action of a water stream has an ink receiving layer. The splittable fiber is a fiber composed of a splittable composite fiber in which two or more kinds of fiber-forming resin components are combined. As long as the splittable fiber can be split by the action of a water flow, the cross-sectional shape of the splittable fiber is There is no particular limitation, and for example, there are forms shown in (a) to (d) of FIG. Among these cross-sectional shapes, the orange shape shown in (a) and (c) is preferable because it can be easily divided and the fiber strength after the division can be increased. The number of divisions of the splittable fiber is not limited, and may be two or more. For example, about 6 to 20 divisions are preferable.

The type of fiber-forming resin constituting the splittable fiber is not particularly limited , and polyamide-based resin (for example, 6 nylon, 66 nylon, etc.), polyester-based resin (for example, polyethylene terephthalate, polybutylene terephthalate, etc.) ) . Among these, it is preferable to select at least a polyester-based resin as one component because high strength and excellent durability and printability can be imparted.

  The thickness of the splittable fiber is not particularly limited as long as spinning conditions and splittability are considered, and the fiber diameter is preferably 10 to 100 μm, and more preferably 20 to 50 μm. Moreover, 0.1-10 micrometers is preferable and the fiber diameter after a division | segmentation has more preferable 0.1-5 micrometers. The fiber diameter before or after division can be the diameter of a circle having the same area as the cross section of the fiber.

The length of the splittable fiber is not particularly limited as long as it is possible to form a nonwoven fabric, and continuous long fibers can be applied to obtain a spunbond nonwoven fabric .

  The nonwoven fabric base fabric containing ultrafine fibers generated by splitting from the splittable fibers is a fiber web composed of fibers containing the splittable fibers by the action of a water flow sprayed from a nozzle head containing high-pressure water. The non-woven fabric is formed by splitting the splitting fibers in the fiber web and intertwining the constituent fibers. The fiber web may include only the splittable fibers or may include other fibers other than the splittable fibers. Examples of such other fibers include polyethylene terephthalate and polybutylene terephthalate. Polyester fibers, polyamide fibers such as nylon 6 and nylon 66, polyolefin fibers such as polypropylene and polyethylene, acrylic fibers such as polyacrylonitrile, and synthetic fibers such as polyvinyl alcohol fibers, semi-synthetic fibers such as rayon, Alternatively, natural fibers such as cotton and pulp fibers can be mentioned. The mixing ratio of other fibers should be kept in a range not losing the characteristics as the base material for inkjet printing of the present invention, and is preferably 30% by mass or less based on the entire nonwoven fabric base fabric formed from the fiber web. 15 mass% or less is more preferable.

Examples of the fiber web include a fiber web made of long fibers in which thermoplastic synthetic fibers are spun from a nozzle and laminated by , for example, a spunbond method . By adopting a fiber web consisting of long fibers by the spunbond method as the fiber web , the strength of the non-woven fabric is increased and the durability is excellent, and the fiber is not fluffed and the surface is also slippery. This is superior to the nonwoven fabric base fabric using short fibers in this respect.

It is also possible to use a fiber web in which the fiber web is preliminarily entangled with a needle punch .

  In order to divide the splittable fiber in the fiber web by the action of a water flow sprayed from a nozzle head containing high-pressure water, it is possible to use a method of producing a nonwoven fabric by a normal water flow entanglement, for example, the fiber The web is placed on a perforated support made of a belt conveyor and the number of nozzle heads containing high-pressure water installed on the top of the fiber web while moving the perforated support is larger. There is a method in which a columnar flow is ejected through a nozzle plate in which nozzle holes are arranged linearly, and a water flow is applied to the fiber web. The diameter of the nozzle holes used in this method is preferably 0.1 to 0.3 mm, the interval between the nozzle holes is preferably 0.5 to 2 mm, and a plurality of nozzle heads are preferably used. The water pressure in the nozzle head is preferably 0.2 to 2 MPa, and for dividing the splittable fiber, 0.5 to 2 MPa is preferable although it depends on the degree of splitting.

As described above, the fiber web composed of the fibers containing the splittable fibers is divided into the splittable fibers in the fiber web by the action of the water flow injected from the nozzle head containing the high-pressure water and the constituent fibers. Are intertwined to form a nonwoven fabric base fabric . Moreover , the nonwoven fabric base fabric can be made into a nonwoven fabric base fabric having improved flexibility by subjecting the nonwoven fabric fabric to a frying process at about 120 ° C. for about 10 minutes using a liquid dyeing machine.

Moreover, 20-300 g / m < ² > is preferable, as for the surface density of the said nonwoven fabric base fabric, 30-200 g / m < ² > is more preferable, and 50-150 g / m < ² > is further more preferable. If it is less than 20 g / m ² , it may not be vivid printing because the fiber density is low, and if it exceeds 300 g / m ² , the cost may increase.

  Thus, since the obtained nonwoven fabric base fabric contains the ultrafine fiber generated by splitting from the splittable fiber by the action of water flow, a clear printed image can be formed by ink jet printing. Further, since the constituent fibers are entangled by the action of the water flow, the water resistance and the durability are excellent, and the excellent effects of excellent flexibility and light weight are achieved.

  In the present invention, the non-woven fabric base fabric may be a non-woven fabric composite base fabric laminated and integrated with a scrim, a net, a burif, and the like. In order to obtain such a nonwoven fabric composite base fabric, for example, after laminating the fiber web and these scrims, nets, walliffs and the like, the splitting fibers contained in the fiber web are made by the action of water flow. It is possible to obtain by dividing. In this case, due to the action of the water flow, the fiber web and these scrims, nets, walliffs, and the like have a laminated and integrated structure.

  In the substrate for ink-jet printing of the present invention, the nonwoven fabric base fabric containing ultrafine fibers generated by splitting from splittable fibers by the action of water flow has an ink receiving layer. The ink receiving layer is a layer that absorbs and fixes printing ink such as inkjet ink, and more preferably a layer that has a function of imparting image bleeding and water resistance.

  As the material constituting the ink receiving layer, any conventionally known material can be used. Specifically, albumin, gelatin, casein, starch, cationic starch, gum arabic, polyvinyl imidazole, agar, hydrophilic natural materials such as sodium alginate, dextrin, viscose, methylcellulose, ethylcellulose, carboxymethylcellulose, hydroxyethylcellulose, cation modification Hydroxyethyl cellulose, polyvinyl alcohol, cation-modified polyvinyl alcohol, acetal-modified polyvinyl alcohol (polyvinyl acetal), polyethylene glycol, polypropylene glycol, polyacrylic acid, water-soluble alkyd, polyvinyl ether, polyvinyl pyrrolidone, quaternized polyvinyl pyrrolidone, polyamide, polyacrylamide , Poly (N-vinyl-3methylpyrrolidone), polymalein Examples include water-soluble or hydrophilic synthetic resins such as copolymers, polyethyleneimine, polyethylene oxide, polyvinylimidazole, polyallylamine, polyallylamine hydrochloride, melamine resin, polyurethane, and polyester. If desired, at least one of these materials is used. It is done.

  The material constituting the ink receiving layer is a biodegradable resin such as poly (α-hydroxy acid) (for example, polyglycolic acid, poly-L-lactic acid, etc.), poly (β-hydroxyalkanoate). ) (For example, poly (β-hydroxybutyric acid), β-hydroxybutyric acid-βhydroxyvaleric acid copolymer, etc.), poly (ω-hydroxyalkanoate) (for example, poly-β-propiolactone, poly-ω- Caprolactone, etc.), polyalkylene dicarboxylates (eg, polyethylene succinate, polybutylene succinate, butylene succinate-butylene adipate copolymer, etc.), and at least one of these materials can be used if desired. It is.

  Further, in particular, for the purpose of improving ink jet recording suitability, for example, beading resistance, blocking resistance, etc., the storage stability of the obtained ink jet recorded material, for example, image bleeding and water resistance in a high humidity environment, etc. For the purpose of improvement, in addition to the above materials, water-soluble low-molecular organic compounds, cationic compounds, and water-insoluble organic compounds can be used as appropriate.

  Examples of water-soluble low molecular weight organic compounds used at this time include polyvalent ethylene glycol, polyethylene glycol, poly (ethylene glycol-propylene glycol) copolymer, D-sorbitol, and sucrose having a molecular weight of 5,000 or less. Alcohol etc. are mentioned.

  Further, as the cationic compound, primary, secondary and tertiary amine salt type compounds, for example, laurylamine, palmamine, stearylamine, rosinamine and other hydrochlorides and acetates; quaternary ammonium salt type compounds, For example, lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltributylammonium chloride, benzalkonium chloride and the like; pyridinium salt type compounds such as cetylpyridinium chloride and the like; imidazoline type cationic compounds such as 2-heptadecenyl-hydroxyethyl Examples include imidazoline and the like; ethylene oxide adducts of higher alkylamines such as dihydroxyethyl stearylamine.

  Furthermore, water-insoluble organic compounds include acrylic resins typified by polymethyl methacrylate, polyamides typified by 6,6 nylon, polyvinyl acetals typified by butyral resins, polyethylene, polypropylene, polystyrene resins, polychlorinated resins. Examples thereof include vinyl, phenol resin, epoxy resin, polyester, polyurethane, diacetate compound, D-sorbitol / aromatic aldehyde condensate and the like.

Further, in order to improve physical properties as an ink jet recording medium, such as blocking resistance, conventionally known organic and / or inorganic fine particles (powder, emulsion, etc.) are added in an amount of 0.01 to 30 g in the ink receiving layer. / M ² , preferably about 1 to ²⁰ g / m ² can be added. Examples of the organic and / or inorganic fine particles include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, and diatomaceous earth. , Calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrous halloysite, magnesium carbonate, magnesium hydroxide, white inorganic pigment, styrenic plastic Examples thereof include organic pigments such as pigment, acrylic plastic pigment, polyethylene, microcapsule, urea resin, and melamine resin. Among these fine particles, the white pigment contained as a main component in the ink receiving layer is preferably a porous inorganic pigment, and examples thereof include porous synthetic amorphous silica, porous magnesium carbonate, and porous alumina. Porous synthetic amorphous silica having a large pore volume is preferred.

  In addition to the fine particles, conventionally known additives such as dispersants, lubricants, antifoaming agents, and other surfactants, oils, pH adjusters, fluorescent dyes, preservatives, and the like are added to the ink receiving layer. It can be used within a range that does not deteriorate the performance of the substrate for ink jet printing in the present invention.

  As a method for forming the ink receiving layer on the nonwoven fabric base fabric, there is a method in which a coating liquid made of the above material is impregnated with, for example, a padder. In addition, there are methods of forming by coating with various blade coaters, roll coaters, air knife coaters, bar coaters, rod coaters, gate roll coaters, curtain coaters, short dwell coaters, gravure coaters, flexographic gravure coaters, size presses and the like. Among these methods, the method of forming by padding impregnation is an advantageous method in that both surfaces of the non-woven fabric can be printed with a single treatment.

  As a specific form in which the nonwoven fabric base has an ink receiving layer, the form differs depending on the method for forming the ink receiving layer described above, and the form obtained mainly by padding impregnation and the like mainly by coating. It can be divided into two types of obtained forms.

  As a form obtained by padding impregnation, etc., the ink receiving layer is formed relatively uniformly over the whole thickness direction of the nonwoven fabric, and the material for forming the ink receiving layer between the fibers is densely packed. And a form in which the material for forming the ink receiving layer is interspersed between the fibers. Specifically, the mass of the material forming the ink receiving layer is preferably 5 to 150 parts, more preferably 5 to 100 parts, with respect to 100 parts of the fiber constituting the nonwoven fabric. More preferably, it is 10 to 50 parts.

  Further, the porosity after forming the ink receiving layer between the fibers is preferably 95 to 10%, more preferably 90 to 20%, and further preferably 90 to 30%. In addition, for the purpose of smoothing the surface of the substrate for ink jet printing and increasing the porosity, the thickness of the nonwoven fabric base fabric after forming the ink receiving layer between the nonwoven fabric base fabric or the fibers is increased by a pressure roll or the like. In this case, the porosity is preferably 85 to 30%, more preferably 80 to 40%, and even more preferably 70 to 40%. In addition, the porosity is defined as Vn, the apparent volume calculated from the surface density and the thickness obtained by the 6.1.2A method defined in JIS L1085-1998 (nonwoven fabric test method). Assuming that the total volume of each material constituting the nonwoven fabric base fabric after forming Vo is Vo, it can be obtained from the formula of porosity Vs (%) = (Vn−Vo) / Vn × 100.

  In addition, as a form in which the ink receiving layer is formed relatively uniformly in the entire thickness direction of the nonwoven fabric base fabric, when the fiber structure is very coarse and the pore diameter is large, it can be obtained not only by padding impregnation but also by coating. It is.

  As the form in which the nonwoven fabric base fabric has an ink receiving layer by coating or the like, the above-mentioned various blade coaters, roll coaters, air knife coaters, bar coaters, rod coaters, gate rolls are provided on at least one surface of the nonwoven fabric base fabric. There is a form in which the ink receiving layer is applied by a method of applying by a coater, curtain coater, short dwell coater, gravure coater, flexographic gravure coater, size press or the like. The coating amount of the ink receiving layer can be determined in consideration of the surface state of the nonwoven fabric base and the permeability into the porous fiber structure. The mass of the material forming the layer is preferably 3 to 80 parts, more preferably 3 to 50 parts, and even more preferably 5 to 30 parts. The form having the ink receiving layer by this coating or the like is characterized in that the density of the ink receiving layer is increased in the vicinity of the surface of the substrate for ink jet printing. When the ink receiving layer is provided on the surface portion substantially free of fibers (for example, 10% or less by mass ratio), the thickness of the ink receiving layer is preferably 1 to 50 μm, 30 μm is more preferable.

The areal density of the ink jet printing substrates, preferably 30~350g / ^{m 2,} more preferably 40~250g / ^{m 2,} more preferably 50 to 200 g / ^{m 2.} If it is less than 30 g / m ² , the surface density of the nonwoven fabric base fabric is small, so that clear printing may not be achieved, and if it exceeds 350 g / m ² , the cost may increase. Moreover, it is preferable that the thickness of the said base material for inkjet printing is 0.1-1.2 mm, 0.13-0.8 mm is more preferable, 0.15-0.7 mm is further more preferable. The thickness is the thickness specified in the 6.1.2A method of JIS L1913-1998. However, the load was 2.0 kPa.

The tensile strength of the inkjet printing substrate is preferably 100 N / 50 mm width or more when converted to an area density of 100 g / m ² when expressed by an average value in the vertical direction and the horizontal direction. A width of 50 mm or more is more preferable, and a width of 200 N / 50 mm or more is more preferable. Further, the tear strength of the inkjet printing substrate is preferably 4N or more, more preferably 5N or more when converted to an average surface density of 100 g / m ² in terms of the average value in the vertical and horizontal directions. . In addition, let the tensile strength be the tensile strength prescribed | regulated to 6.3 of JISL1913-1998. The tear strength is the tear strength specified in 6.4.3 (single tongue method) of JIS L1913-1998.

  In addition, the bending resistance (cantilever method) of the base material for ink jet printing is preferably 300 mm or less, and more preferably 250 mm or less, as an average value in the vertical direction and the horizontal direction. Moreover, in the field | area where a softness | flexibility is requested | required especially, it is preferable that it is 160 mm or less, and 100 mm or less is more preferable. The bending resistance is the bending resistance defined by the 8.19.1A method (45 ° cantilever method) of JIS L1096-1999.

Further, air permeability of the ink jet printing substrate ^is preferably 2~100cm ^{3 /} cm 2 ^{/ sec,} more preferably ^{4~50cm 3 / cm 2 / sec,} 5~30cm 3 / cm 2 / sec Is more preferable. In addition, let air permeability be the air permeability prescribed | regulated to the 8.27.1A method (fragile type method) of JISL1096-1999.

  As described above, according to the present invention, it is a printing substrate made of a nonwoven fabric that is excellent in flexibility and light weight but also excellent in water resistance and durability, and enables a clear printed image formation. It has become possible to provide a substrate for inkjet printing.

  Examples of the present invention will be described below, but these are only suitable examples for facilitating understanding of the invention, and the present invention is not limited to the contents of these examples.

(Printability-Sharpness evaluation method)
A full color image was inkjet printed using a pigment ink or a dye ink, and bleeding and image sharpness were evaluated by visual observation. As the evaluation criteria, “◯” was obtained when there was no blur and the image was clear, “Δ” when the image was slightly blurred but there was no problem in practical use, and “X” when the image was not noticeably blurred.
(Tensile strength and tensile elongation)
It tested by the method prescribed | regulated to 6.3 of JISL1913-1998.
(Tear strength)
It tested by the method prescribed | regulated to 6.4.3 (single tongue method) of JISL1913-1998.
(Flexibility)
It tested by the method prescribed | regulated to the 8.19.1A method (45 degree cantilever method) of JISL1096-1999.
(Air permeability)
It tested by the method prescribed | regulated to the 8.27.1A method (fragile type method) of JISL1096-1999.
(Dye fastness to friction)
It tested by the method prescribed | regulated to JISL0849-2004. Using a Gakushin type friction tester, mount the dried test piece on the test stand, apply a load of 2N to the friction element, and after 100 reciprocations, observe the surface condition of the test piece, The case where there was no or very little was judged as good (◯), the case where there was little change in color was judged as slightly good (Δ), and the case where the color became light was judged as bad (x).
(Abrasion resistance against friction)
It tested by the method prescribed | regulated to JISL0849-2004. Using a Gakushin type friction tester, mount the dried test piece on the test stand, apply a load of 2N to the friction piece, observe the surface condition of the test piece after 100 reciprocations, change the fiber structure and fluff The case where there was no or very little was determined as good (◯), the case where there was little change in fiber structure and fluffing was judged as slightly good (Δ), and the case where the fiber structure was broken or very fluffy was judged as poor (x).

Example 1
By the spunbond method, 2.4 decitex composite fiber having a cross-sectional shape shown in FIG. 1C as a splittable long fiber (fiber diameter 12 μm, resin component 1 is polyester resin, and resin component 2 is 6 nylon resin) Was spun from a nozzle to form a fiber web composed of splittable long fibers. Next, the fiber web was placed on an open support, a columnar flow was ejected from a nozzle head containing high-pressure water, the water flow was applied to the fiber web, and the fiber web was dried with a dryer. . As a result, the splittable long fibers are split by the action of the water flow, and a maximum of 16 ultrafine fibers are generated from each fiber. The generated ultrafine fibers are entangled by the action of the water flow, and the average fiber diameter is 3.1 μm. A non-woven fabric base fabric having an areal density of 100 g / m ² was obtained.
In addition, for forming an ink receiving layer, 50 mass% of an aqueous solution (liquid concentration 21%) in which silica particles and polyvinyl alcohol are added to an acrylic resin emulsion, and a cationic fixing agent (polyallylamine hydrochloride aqueous solution, liquid concentration 35%) 2 A dispersion liquid in which mass% was dispersed in 48 mass% of water was prepared. Next, the nonwoven fabric base was immersed in this dispersion, and then passed between a pair of rubber rolls so as to be impregnated with padder, so that a certain amount of the dispersion was included in the nonwoven fabric. Next, the impregnated nonwoven fabric was dried with a dryer set at a temperature of 150 ° C. to form an ink receiving layer on the nonwoven fabric, thereby obtaining a substrate for inkjet printing. The ink-receiving layer was formed almost uniformly in the thickness direction on this ink jet printing substrate, and printing was possible on both surfaces. Moreover, the surface density of this base material for inkjet printing was 125 g / m < ² >, and thickness was 0.42 mm. Further, the tensile strength was 331 N / 50 mm width in the longitudinal and transverse directions, and the tensile elongation at break was 50% in the longitudinal and transverse directions. The tear strength was 6.2 N in the longitudinal and lateral directions, and the bending resistance was 196 mm in the longitudinal and lateral averages. The air permeability was 6.5 cm ³ / cm ² / sec. In addition, Table 1 shows the results of the evaluation of the sharpness of printing, the dyeing fastness test and the abrasion resistance test.

(Example 2)
In the same manner as in Example 1, a nonwoven fabric base with a surface density of 100 g / m ² was obtained.
In addition, for forming an ink receiving layer, a dispersion was prepared by dispersing 8% by mass of an aqueous solution (liquid concentration 35%) obtained by adding a cationic fixing agent to an acrylic resin emulsion in 92% by mass of water. Next, the nonwoven fabric base was immersed in this dispersion, and then passed between a pair of rubber rolls so as to be impregnated with padder, so that a certain amount of the dispersion was included in the nonwoven fabric. Next, the impregnated nonwoven fabric was dried with a dryer set at a temperature of 150 ° C. to form an ink receiving layer on the nonwoven fabric, thereby obtaining a substrate for inkjet printing. The ink-receiving layer was formed almost uniformly in the thickness direction on this ink jet printing substrate, and printing was possible on both surfaces. Moreover, the surface density of this base material for inkjet printing was 105 g / m < ² >, and thickness was 0.44 mm. In addition, the tensile strength was 323 N / 50 mm width in the longitudinal and transverse directions, and the tensile elongation at break was 65% in the longitudinal and transverse directions. The tear strength was 8.2 N in the average in the longitudinal and lateral directions, and the bending resistance was 92 mm in the average in the longitudinal and lateral directions. The air permeability was 9.6 cm ³ / cm ² / sec. In addition, Table 1 shows the results of the evaluation of the sharpness of printing, the dyeing fastness test and the abrasion resistance test.

(Reference Example 1)
As a splittable short fiber, a 2.2 dtex composite staple fiber having a cross-sectional shape shown in FIG. 1A (fiber diameter 12 μm × 38 mm length, resin component 1 is polyester resin, and resin component 2 is 6 nylon resin) Was supplied to a card machine to prepare a fiber fleece, and the fiber fleece was folded to form a cross lay fiber web. Next, the fiber web was placed on an open support, a columnar flow was ejected from a nozzle head containing high-pressure water, the water flow was applied to the fiber web, and the fiber web was dried with a dryer. . The water pressure was 15 MPa and a plurality of nozzle heads were used. As a result, the splittable short fibers are split by the action of the water stream, and a maximum of 13 ultrafine fibers are generated from each fiber. The generated ultrafine fibers are entangled by the action of the water stream, and the average fiber diameter is 3.3 μm. A non-woven fabric base fabric having an areal density of 85 g / m ² was obtained.
Next, an ink receiving layer was formed in the same manner as in Example 1 to obtain a substrate for inkjet printing. The ink-receiving layer was formed almost uniformly in the thickness direction on this ink jet printing substrate, and printing was possible on both surfaces. Moreover, the surface density of this base material for inkjet printing was 104 g / m < ² >, and thickness was 0.50 mm. Further, the tensile strength was 240 N / 50 mm width in the longitudinal and transverse directions, and the tensile elongation at break was 53% in the longitudinal and transverse directions. In addition, the average value of tear strength in the longitudinal direction and the transverse direction was 11.2 N, and the bending resistance was 155 mm in average value in the longitudinal and transverse directions. The air permeability was 33.2 cm ³ / cm ² / sec. In addition, Table 1 shows the results of the evaluation of the sharpness of printing, the dyeing fastness test and the abrasion resistance test.

(Comparative Example 1)
As the ultrafine fiber, 3.3 dtex composite fiber (fiber diameter 18 μm, fiber length 5 mm, resin component 1 is polyethylene terephthalate resin, resin component 2 is 6 nylon resin) having the cross-sectional form shown in FIG. A 1.7 dtex polyethylene terephthalate fiber (fiber diameter: 13 μm, fiber length: 10 mm) as non-adhesive fiber was dispersed in water containing a dispersant to form a slurry. At this time, the composite fiber was disaggregated into a maximum of 11 portions, and each disaggregated fiber (average fiber diameter 5.5 μm) was an ultrafine fiber having a flat cross section. Next, the slurry was made into a fiber web by papermaking with a hand mill and dried at 110 ° C. Next, the fiber web was placed on an open support, a columnar flow was ejected from a nozzle head containing high-pressure water, the water flow was applied to the fiber web, and the fiber web was dried with a dryer. . The water pressure was 4 MPa and a plurality of nozzle heads were used. As a result, a non-woven fabric substrate having a surface density of 65 g / m ² in which ultrafine fibers were three-dimensionally entangled with a water flow was obtained.
Next, an ink receiving layer was formed in the same manner as in Example 1 to obtain a substrate for inkjet printing. The ink-receiving layer was formed almost uniformly in the thickness direction on this ink jet printing substrate, and printing was possible on both surfaces. Moreover, the surface density of this base material for inkjet printing was 73 g / m < ² >, and thickness was 0.39 mm. Further, the tensile strength was 106 N / 50 mm width in average in the longitudinal direction and the transverse direction, and the tensile elongation at break was 72% in average in the longitudinal direction and the transverse direction. Moreover, the average value of the longitudinal direction and the horizontal direction was 3.6 N for the tear strength, and the bending resistance was 102 mm for the average value in the vertical direction and the horizontal direction. The air permeability was 15.4 cm ³ / cm ² / sec. In addition, Table 1 shows the results of the evaluation of the sharpness of printing, the dyeing fastness test and the abrasion resistance test.

(Comparative Example 2)
A fiber web made of polyester fibers having an average fiber diameter of 3.5 μm is formed by a melt blow method, and the fiber web is partially fused by a pressure roll made of a pair of emboss rolls and a smooth roll to obtain a surface density. A nonwoven fabric base fabric of 80 g / m ² was obtained.
Next, an ink receiving layer was formed in the same manner as in Example 1 to obtain a substrate for inkjet printing. The ink-receiving layer was formed almost uniformly in the thickness direction on this ink jet printing substrate, and printing was possible on both surfaces. Moreover, the surface density of this base material for inkjet printing was 98 g / m < ² >, and thickness was 0.33 mm. In addition, the average value of the tensile strength in the longitudinal direction and the transverse direction was 73 N / 50 mm width, and the tensile elongation at break was 49% in the average value in the longitudinal direction and the transverse direction. The tear strength was 4.0 N in the longitudinal and lateral averages, and the bending resistance was 120 mm in the longitudinal and lateral averages. The air permeability was 4.9 cm ³ / cm ² / sec. In addition, Table 1 shows the results of the evaluation of the sharpness of printing, the dyeing fastness test and the abrasion resistance test.

Table 1

As is apparent from Table 1, ink jet printing substrates of Examples 1 and 2, as compared with Comparative Examples 1 and 2, the value of the tensile strength is high, were excellent in durability. In addition, the ink jet printing base materials of Examples 1 and 2 were excellent in the sharpness of printing, and excellent results were also observed in the dyeing fastness test and the abrasion resistance test.

(A) is an example of the cross section of the splittable fiber used in the present invention, (b) is another example of the cross section of the splittable fiber used in the present invention, and (c) is another cross section of the splittable fiber used in the present invention. An example and (d) are figures which show another example of the cross section of the splittable fiber used by this invention.

Explanation of symbols

1. 1. Resin component Other resin components

Claims (3)

A non-woven fabric containing ultrafine fibers generated by splitting from splittable fibers by the action of water flow is a printing substrate for forming a printed image by ink jet having an ink receiving layer,
The non-woven fabric is formed by the spunbond method, and the splittable long fibers in the fiber web are formed by the action of a water flow sprayed from a nozzle head containing high-pressure water on a fiber web made of continuous splittable long fibers. Is a non-woven fabric formed only by a process in which ultrafine fibers with a fiber diameter of 0.1 to 10 μm are generated and the ultrafine fibers are entangled with each other,
The splittable long fiber is a fiber having a fiber diameter of 10 to 100 μm composed of a composite fiber that can be split by the action of water flow, and a fiber-forming polyester resin component and a polyamide resin component are combined. The ultrafine fiber is a polyester. A base material for ink jet printing comprising a base fiber and a polyamide fiber.   The substrate for inkjet printing according to claim 1, wherein the bending resistance by the cantilever method is 300 mm or less. Tear strength, surface density 100 g / m ² per inkjet printing substrate according to claim 1 or 2, characterized in that at least 4N.

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