Printing substrate and method for manufacturing the same

Abstract

To provide a novel printing substrate and the like.SOLUTION: A printing substrate has a printed portion thereon, the printed portion including a different color printed portion in which different colors are printed with a clearance therebetween.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a novel printing substrate and the like. [Background technology]

[0002] 2. Description of the Related Art Various printing methods (image recording methods) have been known in the past. For example, the inkjet method is a printing method (printing system) in which minute ink droplets are ejected to print (record or form an image). Various inks for such inkjet printing are known according to printing performance, the type of substrate to be printed on, coating film performance, and the like (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-132946 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a novel printing substrate and a method for producing the same.

[0005] As described above, various printing methods have been conventionally known, but when inks of different colors (color inks) are printed adjacent to each other (without spacing between them), the inks may mix between the adjacent colors (at the boundaries between the different colors), resulting in bleeding (color mixing).

[0006] According to the inventors' investigations, such bleeding between different colors is particularly likely to occur in printing methods such as inkjet methods in which ink is printed (image recorded) in a dot pattern, and among such printing methods, bleeding is most noticeable when printing on non- or low-absorbency (liquid-absorbent) substrates (e.g., plastic films, etc.), when using aqueous inks, when printing color inks and clear inks in layers, etc.

[0007] Although inks of different colors are adjacent to each other, they are naturally printed in positions (dots) where they do not overlap, making it extremely difficult to solve this problem of bleeding. [Means for solving the problem]

[0008] In this situation, the inventor conducted extensive research and discovered that when printing inks of different colors adjacent to each other, the problem of bleeding between adjacent colors can be efficiently solved by printing the different colors in such a way that a clearance is created between them. After further research, the inventor completed the present invention.

[0009] That is, the present invention relates to the following inventions, etc. [1] A printing substrate having a printed portion on a substrate, the printed portion including (at least including) a different color printed portion in which different colors are printed with a clearance therebetween. [2] A printing substrate having a printing portion on a substrate, The printing substrate includes at least different color printed portions in which different colors are printed adjacent to each other without causing bleeding. [3] The printing substrate according to [1] or [2], wherein the printing surface of the substrate has a wetting tension of 30 to 50 dyn / cm. [4] The printing substrate according to any one of [1] to [3], wherein the substrate is a plastic film. [5] The printing substrate according to any one of [1] to [4], wherein the printing surface of the substrate is composed of a polyester-based resin. [6] The printing substrate according to any one of [1] to [5], wherein the printed portion is printed by an inkjet method. [7] The printing substrate according to any one of [1] to [6], wherein the printed portion is formed using a water-based ink. [8] The printing substrate according to any one of [1] to [7], wherein the printed portion is formed with a color ink and a clear ink. [9] The printing substrate according to any one of [1] to [8], wherein the printed portion is formed with water-based color inks and water-based clear ink.

[10] The printing substrate according to any one of [1] to [9], wherein the proportion of the resin in the printed portion relative to the total amount of the resin and colorant is 20 mass % or more.

[11] The printing substrate according to any one of [1] to

[10] , wherein the width of the clearance is 10 to 1500 μm.

[12] The printing substrate according to any one of [1] to

[11] , comprising a different color printed portion in which, when the different colors are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the clearance width is B (μm), the value of B / A is 8 or less.

[13] The printing substrate according to any one of [1] to

[12] , comprising a different color printed portion having an X / Y value of 20 to 800, where X (dpi) is the printing resolution and Y is the number of pixels corresponding to the width of the clearance.

[14] The printing substrate according to any one of [1] to

[13] , comprising a different color printed portion 1, in which, when the different colors of the different color printed portion are colors 1 and 2, the width of color 1 or the width of color 2 is 500 μm or less, and when the printing resolution is X (dpi) and the number of pixels corresponding to the clearance width is Y, the value of X / Y is 50 or more.

[15] The printing substrate according to

[14] , wherein in the different color printed portion 1, the width of color 1 or the width of color 2 is 400 μm or less, and the value of X / Y is 100 or more.

[16] The printing substrate according to any one of [1] to

[15] , comprising a different-color printed portion 2, in which, when the different colors are color 1 and color 2, the width of color 1 or the width of color 2 exceeds 500 μm, and when the printing resolution is X (dpi) and the number of pixels corresponding to the clearance width is Y, the value of X / Y is 200 or less.

[17] The printing substrate according to

[16] , wherein in the different color printed portion 2, the width of color 1 or the width of color 2 is 600 μm or more, and the value of X / Y is 150 or less.

[18] The printing substrate according to any one of [1] to

[17] , wherein the different color printed portion comprises a different color printed portion 1 according to

[14] or

[15] , and a different color printed portion 2 according to

[16] or

[17] .

[19] The printing substrate according to any one of [1] to

[18] , wherein the different color printed portion includes a different color printed portion in which one of the different colors is white.

[20] The printing substrate according to any one of [1] to

[19] , comprising a different color printed portion, in which, when the different colors are colors 1 and 2, color 1 is a pattern and color 2 is a background. [twenty one] The printing substrate according to any one of [1] to

[20] , comprising a different color printed portion recognizable as a barcode or a two-dimensional code, in which color 1 is a barcode or two-dimensional code and color 2 is a background, when the different color printed portion has different colors, colors 1 and 2. [twenty two] The printing substrate according to any one of [1] to

[21] , for forming a soft medical bag (for example, an infusion bag). [twenty three] A method for producing a printed substrate according to any one of [1] to

[22] , at least through a printing step of printing a printed portion on a substrate, wherein in the printing step, the different color printed portions are printed with a clearance between the different colors. [twenty four] A method for suppressing or preventing bleeding between different colors in a different color printed portion in a printing substrate having a printed portion including a different color printed portion in which different colors are printed adjacent to each other on the substrate, the method including printing the different color printed portion by providing a clearance between the different colors in a printing process for printing the printed portion on the substrate. [twenty five] The method according to

[23] or

[24] , wherein printing is performed by an inkjet method.

[26] The method according to any one of

[23] to

[25] , wherein in the printing step, printing is performed by ejecting color inks and clear ink.

[27] The method according to any one of

[23] to

[26] , wherein printing is performed so that the clearance width is 10 to 1500 μm.

[28] The method according to any one of

[23] to

[27] , wherein the different colors are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the width of the clearance is B (μm), and a clearance is provided so that the value of B / A is 8 or less.

[29] The method according to any one of

[23] to

[28] , wherein the clearance is set so that the value of X / Y is 20 to 800, where X (dpi) is the printing resolution and Y is the number of pixels corresponding to the width of the clearance.

[30] A molded product made from any of the printing substrates [1] to

[22] .

[31] The molded article according to

[30] , which is a soft medical bag. Effect of the Invention

[0010] According to the present invention, a novel printing substrate and a novel method for manufacturing a printing substrate can be provided. Such a printing substrate and manufacturing method can efficiently prevent (or suppress) bleeding between different colors. Such a printing substrate and method are preferable because, even though different colors (inks of different colors) are printed adjacent to each other, bleeding does not impair visibility or design. In particular, when the printing substrate is a pharmaceutical packaging material, medical accidents such as mixing up pharmaceuticals can be prevented by preventing a decrease in visibility due to bleeding. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a close-up photograph of a different color printed portion 1 of the printing substrate obtained in Example 1. [Diagram 2] FIG. 2 is a micrograph of a different color printed portion 1 of the printed substrate obtained in Example 1. As shown in FIG. [Diagram 3] FIG. 3 is a close-up photograph of the different color printed portion 2 of the printing substrate obtained in Example 1. [Figure 4] FIG. 4 is a micrograph of the different color printed portion 2 of the printed substrate obtained in Example 1. As shown in FIG. [Diagram 5] FIG. 5 is a close-up photograph of the different color printed portion 3 of the printing substrate obtained in Example 1. [Figure 6] FIG. 6 is a micrograph of the different color printed portion 3 of the printed substrate obtained in Example 1. As shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <Printing base material> A printing substrate has a printed portion (coating, film) on a substrate. In other words, a printing substrate has a substrate and a printed portion formed (provided) on the substrate.

[0013] The printed portion has at least a printed portion printed in a different color (different color printed portion), and the present invention is characterized by the different color printed portion.

[0014] That is, in the first aspect of the present invention, in the different color printed portion, different colors are printed adjacently (without spacing) without bleeding. As described above, when different colors are printed adjacently, bleeding may occur between the adjacent different colors, but in the first aspect, the different colors are printed adjacently without such bleeding.

[0015] In a second aspect of the present invention, in the different color printed portion, different colors are printed with a clearance (gap) between them (there is a clearance between the different colors).

[0016] In the second embodiment, since there is a clearance between the different colors, bleeding (color mixing) does not usually occur between the different colors, as in the first embodiment.

[0017] Such printed substrates according to the first and second aspects of the present invention can usually be obtained efficiently by printing so that clearances are generated between different colors, as described below.

[0018] Through such printing, when the clearance set during printing is reflected in the different color printed portion, a different color printed portion having a clearance between different colors (a different color printed portion of the second aspect) is formed.

[0019] On the other hand, even if printing is performed so that a clearance is generated (set so that a clearance is provided), different color inks may spread slightly into the spaces between each other depending on the type of substrate, the type of ink, the printing method, etc.

[0020] In such a case, by adjusting the size of the clearance and matching the size (width) of the clearance with the size (width) of the spread, different color inks spread close to each other but do not bleed, and a different color printed area is formed in which there is (apparently) no clearance between the different colors (different color printed area of ​​the first embodiment).

[0021] For this reason, the first aspect can also be said to be a special aspect of the second aspect (an aspect in which the clearance set during printing is not (apparently) reflected in the different color printed portion, and no bleeding occurs).

[0022] This will be explained in further detail below.

[0023] [Base material] Examples of the substrate (recording medium, print-receiving medium) include plastic, metal, wood, paper, etc., and the substrate may be a combination of these.

[0024] Examples of plastics include polyester-based resins (e.g., polyethylene terephthalate, polybutylene terephthalate, etc.), polycarbonate-based resins, olefin-based resins (e.g., polyethylene, polypropylene, cyclic olefin-based resins), halogen-based resins (e.g., polyvinyl chloride), acrylic resins, styrene-based resins, polyamide-based resins, etc.

[0025] The type of such substrate (material) can be selected depending on the application, handling, productivity, printability, etc. For example, polyester-based resins may be suitably used from the viewpoints of printability, high-speed bag-making properties (high-speed sealing properties), etc.

[0026] The shape of the substrate may be any one-dimensional (e.g., rod-like), two-dimensional (e.g., film (or sheet)-like), or three-dimensional (e.g., various molded products), and typically may be a film (sheet)-like shape.

[0027] The film-like substrate may be a stretched film. The film-like substrate may be a laminated film, or may be in a bag shape (tube shape, tube film, inflation film), or the like.

[0028] The substrate may be a coated substrate (eg, coated paper) or a substrate that has been surface treated (eg, corona discharge treated, plasma treated).

[0029] Such treatment may be performed at least on the printing portion of the substrate (the recording portion, the portion where the printed portion is formed, for example, the printing surface of a film-like substrate) (the same applies below to the characteristics and physical properties of the substrate).

[0030] The substrate may be transparent, depending on the material.

[0031] Representative substrates include plastic films, particularly transparent plastic films.

[0032] The substrate may be colored or colorless.

[0033] The substrate (the printed surface of the substrate, the portion on which the printed portion is formed) may be particularly low or non-liquid absorbing (particularly low or non-water absorbing). In the present invention, even with such a substrate, a different color printed portion without bleeding (or having clearance) between different colors can be efficiently formed.

[0034] The wetting tension of the substrate (the printed surface of the substrate, the portion where the different color printed portion is formed) may be, for example, about 25 to 55 dyn / cm, preferably 28 to 52 dyn / cm, and more preferably 30 to 50 dyn / cm (eg, 32 to 45 dyn / cm, 33 to 42 dyn / cm).

[0035] The wetting tension can be measured, for example, according to (conformity with) JIS K 6768. As the wetting reagent, for example, a mixture for wetting tension testing (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., etc.), a dyne pen for checking wettability (enerdyne series, manufactured by Enercon, Inc., etc.), etc. can be used. A specific method is to dip the tip of a cotton swab in the mixture for wetting tension testing, and then wet the surface of the printed material with the cotton swab. The area where the liquid has spread to some extent even after about 2 seconds, and the area where the liquid is repelled, are examined using the mixture with different grit sizes.

[0036] Wetting tension can be related to the wettability of the ink used in printing, and thus to the ease of printing (recording), but the greater the wettability, the more likely adjacent colors are to mix (bleed). In the present invention, it is possible to efficiently achieve both sufficient ease of printing (moderate wettability) and prevention (suppression) of bleeding.

[0037] [ink] The printed portion (different color printed portion) is usually formed with ink (ink composition).

[0038] In addition, if the ink contains volatile components (solvent components), the printed area (different color printed area) will be composed of the volatile components that have volatilized (evaporated) from the ink, i.e., the solid components of the ink (colorant, resin, etc., as described below).

[0039] The ink may be at least a color ink, and may be combined with other inks (clear ink, etc.) as necessary.

[0040] (Color ink) As the colorant (coloring material) contained in the color ink, either a white colorant or a non-white colorant (yellow, cyan, magenta, black, gray, red, orange, green, etc.) can be used.

[0041] In particular, the color constituting the different color printed portion may contain at least a white colorant. When the different colors constituting the different color printed portion contain white (and further, in particular when the base material is transparent), the clearance provided in the different color printed portion tends to be difficult to visually confirm (hard to stand out), and bleeding can be prevented in a natural way without making the clearance stand out.

[0042] As the colorant, for example, a dye or a pigment may be used, and preferably, a pigment may be used. The pigment may be either an inorganic pigment or an organic pigment.

[0043] Examples of inorganic pigments include metal compounds (such as titanium oxide, basic lead carbonate, zinc sulfide, iron oxide, red iron oxide, and chromium oxide), and carbon black (such as furnace black, acetylene black, and channel black).

[0044] Examples of organic pigments include azo pigments (such as azo lake pigments), phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, and diketopyrrolopyrrole pigments.

[0045] The color index (CI) of the colorant is not particularly limited, and examples of color indexes of white pigments include CI Pigment White 1 (basic lead carbonate), 4 (zinc oxide), 5 (mixture of zinc sulfide and barium sulfate), 6 (titanium oxide), 6:1 (titanium oxide containing other metal oxides), 7 (zinc sulfide), 18 (calcium carbonate), 19 (clay), 20 (titanium mica), 21 (barium sulfate), 22 (natural barium sulfate), 23 (gloss white), 24 (alumina white), 25 (gypsum), 26 (magnesium oxide-silicon oxide), 27 (silica), and 28 (anhydrous calcium silicate).

[0046] The colorant (pigment) may be surface-treated (may be a self-dispersing pigment) or may be in a form dispersed in a dispersant (surfactant, resin, etc.) (dispersion-type pigment).

[0047] The color ink may generally contain a resin (resin component). The resin may be used from the viewpoint of the scratch resistance and adhesion of the coating film (film).

[0048] Examples of the resin include acrylic resins, styrene acrylic resins, styrene resins, vinyl carboxylate ester resins (e.g., vinyl acetate resins), olefin resins, rosin-modified resins, terpene resins, diene resins (e.g., butadiene resins), halogen-based resins (e.g., vinyl chloride resins), polyester resins, urethane resins (polyurethane resins), polyamide resins, and epoxy resins.

[0049] In addition, if a resin can be formed in the coating film [for example, by reacting (polymerizing, condensing, etc.) as the coating film dries to polymerize or crosslink], a component that serves as a resin precursor or a prepolymer (for example, a polyisocyanate-based compound, a polyol-based compound, etc.) can also be used as the resin (resin component).

[0050] The resins may be used alone or in combination of two or more kinds.

[0051] The resin may have a functional group (reactive group), such as an acid group (such as a carboxy group), an amino group, a hydroxy group, a mercapto group, an epoxy group, an isocyanate group, a carbodiimide group, or an oxazoline group.

[0052] The resin may have one or more types of functional groups.

[0053] Such functional groups can contribute to crosslinking of the printed ink (coating film).

[0054] The form of the resin is not limited, but may be particularly particulate (resin particles), typically such a resin emulsion particle (resin particles constituting an emulsion). Such an emulsion particle may contain a dispersant (surfactant).

[0055] The color ink may have a crosslinking property, which makes it possible to form a stronger coating (printing coating).

[0056] Such crosslinking properties can be imparted to the color inks, for example, by using a resin having at least a functional group as the resin and incorporating into the color ink a component (crosslinking agent) that can react with this functional group to form crosslinks, or by incorporating into the color ink a crosslinking agent that reacts with the resin that constitutes the clear ink described below.

[0057] The crosslinking agent (crosslinkable component) can be appropriately selected depending on the type of functional group possessed by the resin constituting the color ink and / or the resin constituting the clear ink.

[0058] For example, when the functional group is a carboxyl group or the like, a crosslinking agent having a group reactive to the carboxyl group (for example, an isocyanate group, an epoxy group, a carboidimide group, an oxazoline group, or the like) may be used.

[0059] In addition, the functional group or reactive group (and further the crosslinking agent) may be protected (blocked) in the ink (ink before printing) as long as it can be crosslinked in the coating. In such a case, deprotection and crosslinking are performed in the coating.

[0060] In the printed portion (different color printed portion), the crosslinking agent (crosslinkable component) crosslinks the resin, that is, it is a constituent component of the resin.

[0061] The color ink may contain, for example, a dispersant, a surfactant, an antifoaming agent, a dissolution aid, a viscosity adjuster, a pH adjuster, an antioxidant, a preservative, an antifungal agent, a corrosion inhibitor, etc. These may be contained in the color ink alone or in combination of two or more kinds.

[0062] The color ink may be oil-based, water-based, or the like, but water-based ink (water-based ink) may be preferably used in consideration of environmental aspects, etc. Water-based ink is likely to cause bleeding between different colors (particularly, bleeding is likely to occur remarkably when printing on a substrate such as a plastic film) possibly because it tends to take a long time to dry, but in the present invention, bleeding between different colors can be efficiently suppressed even when water-based ink is used.

[0063] The solvent contained in the color ink can be appropriately selected according to the classification of the ink, such as oil-based or water-based.

[0064] For example, the solvent contained in the aqueous ink may be composed of at least water, and may contain an organic solvent (water-soluble organic solvent) as necessary.

[0065] Examples of such organic solvents include alcohol-based solvents, ether-based solvents, nitrogen-based solvents (e.g., chain amide-based solvents such as N,N-dimethylformamide and N,N-dimethylacetamide; cyclic amide-based solvents such as 2-pyrrolidone, N-methyl-2-pyrrolidone and 2-oxazolidone; urea derivatives such as 1,3-dimethyl-2-imidazolidinone and 1,1,3,3-tetramethylurea), and sulfur-based solvents (e.g., dimethyl sulfoxide and sulfolane).

[0066] Examples of alcohol-based solvents include monools (e.g., alkanols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butanol, 2-butanol, t-butanol, isobutanol, n-pentanol, 2-pentanol, 3-pentanol, and t-pentanol), and polyols (e.g., alkanediols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol; polyalkanediols such as diethylene glycol, dipropylene glycol, and triethylene glycol; and aliphatic polyols such as aliphatic polyols having three or more hydroxyl groups, such as glycerin).

[0067] Examples of the ether-based solvent include mono- and polyethers of polyols (such as the polyols exemplified above) [for example, alkanediol monoalkyl ethers such as ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-n-propyl ether, propylene glycol monoisopropyl ether, and propylene glycol mono-n-butyl ether; diethylene glycol mono-n-propyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monobutyl ... polyalkanediol monoalkyl ethers such as diethylene glycol mono-t-butyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol mono-n-propyl ether, and dipropylene glycol monoisopropyl ether; and polyol polyalkyl ethers (for example, polyalkanediol dialkyl ethers) such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol ethyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol dimethyl ether.

[0068] The organic solvents may be used alone or in combination of two or more kinds.

[0069] In the color inks, the ratio of each component can be appropriately selected depending on the printing method (for example, ejection properties in an inkjet method), the viscosity of the ink, and the like.

[0070] For example, in color inks, the proportion of colorant may be, for example, 0.1 mass % or more (e.g., 0.5 to 30 mass %), preferably 1 mass % or more (e.g., 1.5 to 20 mass %), and more preferably 2 mass % or more (e.g., 3 to 15 mass %).

[0071] Furthermore, in the color ink, the proportion of the resin (resin component) may be, for example, 0.1 mass % or more (e.g., 0.5 to 30 mass %), preferably 1 mass % or more (e.g., 1.5 to 20 mass %), and more preferably 2 mass % or more (e.g., 3 to 15 mass %).

[0072] When the color ink contains a crosslinking agent, the proportion of the crosslinking agent will vary depending on the type and amount of resin, but may be, for example, 0.01 mass % or more (e.g., 0.05 to 10 mass %), preferably 1 mass % or more (e.g., 0.1 to 5 mass %), and more preferably 0.3 mass % or more (e.g., 0.5 to 3 mass %).

[0073] In the color ink, the ratio of the solvent can be selected according to the viscosity, composition, and the like of the ink. For example, in an aqueous ink, the proportion of water may be, for example, 20% by mass or more (e.g., 30 to 90% by mass), preferably 40% by mass or more (e.g., 45 to 80% by mass), and more preferably 50% by mass or more (e.g., 50 to 75% by mass).

[0074] When the aqueous ink contains an organic solvent (water-soluble organic solvent), the proportion of the water-soluble organic solvent may be, for example, 1 mass % or more (e.g., 3 to 60 mass %), preferably 5 mass % or more (e.g., 8 to 50 mass %), and more preferably 10 mass % or more (e.g., 15 to 40 mass %).

[0075] The viscosity of the color ink at 32° C. may be, for example, about 1 to 80 mPa·s, preferably about 2 to 50 mPa·s, and more preferably about 3 to 30 mPa·s.

[0076] The viscosity can be measured, for example, by a viscometer (such as an E-type viscometer, a B-type viscometer, or an Ubbelohde viscometer) or a capillary rheometer.

[0077] (clear ink) The color ink may be combined with a clear ink. In this manner, a printed portion (a printed portion of different colors) is formed by the color ink and the clear ink (an ink set of the color ink and the clear ink).

[0078] The purpose of using the clear ink is not particularly limited, but one of the purposes may be to increase the ratio of resin (or the ratio of resin to colorant) in the entire ink (or printed part). In particular, when printing on a substrate such as a plastic film, increasing the amount of resin makes it easier to efficiently form a printed part that is excellent in terms of abrasion resistance, adhesion, etc.

[0079] Here, if the only goal is to increase the resin ratio, it would be sufficient to increase the amount of resin in the color ink; however, doing so would increase the viscosity of the ink, which could cause problems such as impairing the ejection properties in the inkjet method.

[0080] Therefore, from the viewpoint of efficient printing, etc., the clear ink may be preferably used.

[0081] The clear ink usually contains a resin (resin component). Examples of such resins include the resins exemplified above (e.g., acrylic resins, styrene-acrylic resins, urethane resins, etc.), and may have the same functional groups as those described above.

[0082] The clear ink may also have crosslinking properties, and the manner in which this occurs is the same as described above. For example, the clear ink may contain a crosslinking agent (such as the components exemplified above), and the crosslinking agent may react with a resin contained in the clear ink (e.g., a resin having a functional group) and / or a resin constituting the color ink (a resin having a functional group).

[0083] Generally, the clear ink does not need to contain a colorant (coloring agent).

[0084] The clear ink may also contain a dispersant, a surfactant, an antifoaming agent, a dissolution aid, a viscosity adjuster, a pH adjuster, an antioxidant, a preservative, an antifungal agent, a corrosion inhibitor, and the like.

[0085] The clear ink may be oil-based, water-based, etc., but water-based ink (water-based ink) may be preferably used. In particular, it is preferable to match the color ink and the clear ink with each other in oil-based or water-based, and typically, both the color ink and the clear ink may be water-based ink.

[0086] As described above, the use of clear ink (and even aqueous ink) results in a relatively larger amount of solvent (particularly water content) during printing (and thus a longer drying time) compared to when only color inks are used, making bleeding between different colors more likely to occur; however, in the present invention, even when clear ink (and even when aqueous ink) is used, bleeding can be efficiently suppressed.

[0087] The solvent contained in the clear ink can be appropriately selected according to the classification of the ink, such as oil-based or water-based. For example, the solvent contained in the aqueous ink may be composed of at least water, and may contain an organic solvent (water-soluble organic solvent) as necessary.

[0088] Examples of the water-soluble organic solvent include those exemplified above (alcohols, ethers).

[0089] In the clear ink, the proportion of the resin (resin component) may be, for example, 0.1 mass % or more (e.g., 0.5 to 30 mass %), preferably 1 mass % or more (e.g., 1.5 to 20 mass %), and more preferably 2 mass % or more (e.g., 3 to 15 mass %).

[0090] When the clear ink contains a crosslinking agent, the proportion of the crosslinking agent will vary depending on the type and amount of resin, but may be, for example, 0.01 mass % or more (e.g., 0.05 to 10 mass %), preferably 1 mass % or more (e.g., 0.1 to 5 mass %), and more preferably 0.3 mass % or more (e.g., 0.5 to 3 mass %).

[0091] The ratio of the solvent in the clear ink can be selected according to the viscosity, composition, and other factors of the ink. For example, in an aqueous ink, the proportion of water may be, for example, 20% by mass or more (e.g., 30 to 90% by mass), preferably 40% by mass or more (e.g., 45 to 80% by mass), and more preferably 50% by mass or more (e.g., 50 to 75% by mass).

[0092] When the aqueous ink contains an organic solvent (water-soluble organic solvent), the proportion of the water-soluble organic solvent may be, for example, 1 mass % or more (e.g., 3 to 60 mass %), preferably 5 mass % or more (e.g., 8 to 50 mass %), and more preferably 10 mass % or more (e.g., 15 to 40 mass %).

[0093] The viscosity of the clear ink at 32° C. may be, for example, about 1 to 80 mPa·s, preferably about 2 to 50 mPa·s, and more preferably about 3 to 30 mPa·s.

[0094] The viscosity can be measured, for example, by a viscometer (such as an E-type viscometer, a B-type viscometer, or an Ubbelohde viscometer) or a capillary rheometer.

[0095] [Printing Department and Different Color Printing Department] As described above, the printing substrate has a printed portion on the substrate, and this printed portion includes at least a different color printed portion.

[0096] In the printed portion (different color printed portion), the ratio of the resin (resin component) to the total amount of the resin (resin component) and colorant can be selected depending on the type of substrate, coating film performance, etc., but may be, for example, 10 mass % or more, preferably 20 mass % or more, more preferably 30 mass % or more, and particularly 50 mass % or more. The upper limit of the proportion of the resin relative to the total amount of the resin and colorant may be, for example, 95 mass %, 90 mass %, 85 mass %, 80 mass %, 75 mass %, 70 mass %, etc. Specific examples of the ratio of the resin (resin component) to the total amount of the resin (resin component) and colorant include 10 to 95 mass %, 30 to 90 mass %, and 50 to 80 mass %.

[0097] In addition, since the crosslinking agent is a component that reacts with resins, etc., when a printed portion is formed using a crosslinking agent, the crosslinking agent also constitutes the resin in the printed portion.

[0098] By ensuring that the amount of resin in the printed portion is sufficient, as described above, a strong coating film (printed portion) can be efficiently formed even on a substrate such as a plastic film. As described above, the use of clear ink is advantageous for increasing the amount of resin, but in the present invention, even when such clear ink is used, bleeding between different colors can be efficiently suppressed as described above.

[0099] The printed portion may be printed in a dot pattern, depending on the printing method used. Such a printed portion can be typically formed by an inkjet method.

[0100] In addition, when printing in a dot pattern using an inkjet method or the like, the dots may be reflected in the printed portion (different color printed portion) [the printed portion (different color printed portion) may be formed in a dot pattern (the printed portion is composed of dots)], or some or all of the dots may be crushed.

[0101] Although it depends on the type of ink (e.g., whether or not clear ink is used, whether or not water-based ink is used, etc.) and resolution, even if printed in a dot pattern, adjacent dots (or ink ejected onto them) may mix together, causing the dots to be significantly crushed (e.g., the dots may appear to disappear). In the present invention, even in such cases where bleeding is likely to occur, bleeding between different colors can be efficiently suppressed.

[0102] The dot density (resolution) can be appropriately selected according to the desired printed portion, and may be selected from a range such as 50 dpi or more, 100 dpi or more, preferably 200 dpi or more, and more preferably 300 dpi or more. The upper limit of the resolution may be, for example, 1200 dpi, 1000 dpi, 800 dpi, 600 dpi, or the like. Specific examples of the resolution include 50 to 1200 dpi, 200 to 1000 dpi, and 300 to 800 dpi.

[0103] As described above, bleeding becomes more likely as the resolution increases, but the present invention can effectively suppress bleeding between different colors even at a relatively high resolution.

[0104] The resolution may be the same or different in the entire area of ​​the printing section. For example, the resolution may be the same or different in the printing direction (vertical direction) and the direction perpendicular to the printing direction (horizontal direction).

[0105] Furthermore, when using clear ink, as long as it is printed (ejected) in the same position (dot) as the colored inks, the colored ink dots and the clear ink dots may be the same or different (for example, the clear ink dots may at least overlap the colored ink dots).

[0106] In the different color printed portion, different colors are printed adjacent to each other (or with a clearance between them).

[0107] The width (size) of each color among the different colors can be selected from small to large depending on the desired printed portion, and for example, the width (length) in the different color directions may be, for example, more than 500 μm (colors with a relatively large width, for example, 550 μm or more, 600 μm or more, 800 μm or more, 1000 μm or more, 2000 μm or more, 10000 μm or more, etc.), or may be 500 μm or less (colors with a relatively small width, for example, 480 μm or less, 450 μm or less, 400 μm or less, 350 μm or less, 300 μm or less, 250 μm or less, 200 μm or less, 150 μm or less, 100 μm or less, etc.). The upper limit of the color width is not particularly limited and can be appropriately selected depending on the intended use of the printing substrate, and may be, for example, 50,000 μm, 30,000 μm, 10,000 μm, 8,000 μm, 5,000 μm, 4,000 μm, 3,000 μm, etc. Similarly, the lower limit of the color width can be appropriately selected depending on the intended use of the printing substrate, and may be, for example, 10 μm, 20 μm, 30 μm, 50 μm, 80 μm, 100 μm, etc. A specific range of the color width is an appropriate combination of the above lower limit and upper limit, for example, 100 to 10,000 μm.

[0108] The widths of different colors may be the same or different. To explain a specific example, assuming that adjacent different colors are colors 1 and 2, respectively, the widths of colors 1 and 2 may be the same or different (for example, the widths of colors 1 and 2 are both greater than 500 μm or less than 500 μm, but are different, such as the case where the width of color 1 is greater than 500 μm and the width of color 2 is less than 500 μm).

[0109] As described later, when one of the different colors (e.g., color 1) is a pattern and the other (e.g., color 2) is its background, the width of the color may not be clearly defined, or the width of the other color may be significantly larger than the width of the other color. In such cases, from the viewpoint of the width of one of the clear colors (e.g., color 1) and its tendency to affect the visibility of the clearance, the width of the smaller color (e.g., color 1) or the width of the color that constitutes the pattern may be used (or various adjustments may be made using this). In addition, when the color width fluctuates (for example, when the pattern is not of a constant width, when the color is the background, etc.), the narrowest width may be used as the color width.

[0110] In the different color printed portion of the second embodiment, the width (width in the direction of different colors) of the clearance (gap between different colors) may be selected, for example, from a range of about 2000 μm or less, and may be about 1500 μm or less, preferably 1000 μm or less, and more preferably about 800 μm or less (e.g., 700 μm or less), or may be 600 μm or less (e.g., 500 μm or less, 400 μm or less, 350 μm or less).

[0111] The lower limit of the clearance width may be, for example, 3 μm, 5 μm, 7 μm, 10 μm, 15 μm, 20 μm, 30 μm, 50 μm, etc. Specific examples of the clearance width include 3 to 2000 μm, 10 to 1000 μm, 20 to 500 μm, 30 to 400 μm, 50 to 300 μm, and 100 to 200 μm.

[0112] It is preferable that the width of the clearance is not too large, since the presence or absence of the clearance is noticeable. On the other hand, in order to make the clearance less noticeable, it is considered better that the width of the clearance is closer to 0. However, in order to print all of the multiple different color printed parts so that the clearance is substantially unnoticeable as in the first embodiment, complicated print settings may be required, and color mixing (bleeding) may occur in some of the different color printed parts. Also, even if the width of the clearance is a somewhat finite value, there are cases in which the presence of the clearance is not noticeable (for example, the presence or absence of the clearance is almost unnoticeable, at least with the naked eye). Therefore, it is realistic for the width of the clearance to be a finite value within a range that is not too large.

[0113] The width of the clearance may be the same as or different from the clearance set during printing (corresponding to the set clearance described below). For example, even if printing is performed so that a clearance of a predetermined width X is generated in the printing settings, the width of the clearance in the different color printed portion may be smaller than X because the color inks spread slightly between different colors.

[0114] When it becomes small in this way, the width of the clearance of the different color printed part (the clearance that can actually be confirmed on the printing substrate) depends on the actually set width and the color width, etc., but for example, when the width of the clearance set in printing is 1, it may be 0.99 or less, 0.98 or less, 0.97 or less, 0.96 or less, 0.95 or less, 0.9 or less, 0.85 or less, 0.8 or less, 0.75 or less, 0.7 or less, 0.65 or less, 0.6 or less, 0.55 or less, 0.5 or less, etc., and the lower limit value may be, for example, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, etc. Specific examples of the clearance width of the different color printed portion, assuming that the clearance width set in printing is 1, include 0.1 to 0.99, 0.2 to 0.98, 0.3 to 0.97, and 0.4 to 0.96.

[0115] The amount of clearance in the different color prints may be selected depending on the width of the different colors and the printing resolution.

[0116] For example, when the different colors are colors 1 and 2, the width of color 1 or the width of color 2 (e.g., the smaller width of these, the width of the color forming the pattern) is A (μm), and the clearance width is B (μm), the value of B / A can be selected from a range of about 10 or less (e.g., 9.5 or less, 9 or less), and may be about 8 or less (e.g., 7.5 or less), preferably 7 or less (e.g., 6 or less), more preferably 5 or less (e.g., 4 or less), particularly 3 or less (e.g., 2.5 or less), or may be 2 or less (e.g., 1 or less, 0.8 or less, 0.5 or less, 0.3 or less, 0.1 or less), etc. Examples of the lower limit of the B / A value include 0.005, 0.01, 0.015, 0.02, 0.03, 0.05, 0.08, 0.1, 0.15, 0.2, 0.3, 0.4, and 0.5. Specific examples of B / A include 0.005 to 7, 0.01 to 5, 0.15 to 3, and 0.2 to 2.

[0117] The visibility of the clearance also appears to be affected by the width of the color (if the widths of different colors are different, the smaller (narrower) width), and within the above range, bleeding can be efficiently suppressed while preventing the clearance from being noticeable.

[0118] Furthermore, when the printing resolution is X (dpi) and the number of pixels corresponding to the clearance width is Y, the value of X / Y [dpi / number (number of pixels)] may be, for example, approximately 20 to 800 (e.g., 22 to 700, 25 to 650, 28 to 600, 30 to 550, 40 to 500, 45 to 450).

[0119] For example, when the resolution is 600 dpi and the number of pixels corresponding to the clearance width is 2 pixels, the clearance width is 2 pixels [approximately 85 μm (2.54 cm ÷ 600 × 2)], the X / Y value is 300, and falls within the above X / Y value range (20 to 800).

[0120] The visibility of the clearance also seems to affect the resolution, and by setting the clearance in relation to the resolution as described above, it is possible to efficiently suppress bleeding while reducing the visibility of the clearance.

[0121] Also, such X / Y values ​​may be selected according to the range of different colors.

[0122] For example, in a different color printed portion, when the width of color 1 or the width of color 2 (e.g., the smaller of these, the width of the color forming the pattern) is relatively small (e.g., 500 μm or less, 300 μm or less, 200 μm or less), the value of X / Y may not be too small (e.g., 50 or more, 80 or more, 100 or more, 120 or more, more than 120, 125 or more, etc.).

[0123] On the other hand, in the different color printed portion, when the width of color 1 or the width of color 2 (e.g., the smaller of these, the width of the color forming the pattern) is relatively large (e.g., more than 500 μm, 600 μm or more), the value of X / Y may not be too large (e.g., 200 or less, 150 or less, 120 or less).

[0124] By selecting the X / Y values ​​according to the width of the color in this way, it becomes easier and more efficient to reduce the visibility of the clearance.

[0125] The printed portion (different color printed portion) may be plain or may have (form) a pattern. The pattern is not particularly limited and can be selected depending on the use of the substrate (printing substrate) and the purpose of its display. Examples of the pattern include letters (e.g., hiragana, katakana, kanji, alphabet, etc.), numbers (e.g., Arabic numerals, Roman numerals, etc.), figures, etc. The graphic may be a pattern (graphical pattern) such as a barcode or a two-dimensional code.

[0126] However, if the barcode bleeds or the clearance becomes too large, it becomes difficult or impossible to recognize (difficult or impossible to read), and therefore it is difficult to print a recognizable barcode.

[0127] However, in the present invention, as described above, by adjusting the width of the clearance using a specific index, it is possible to print (record) a barcode that can be efficiently recognized (read).

[0128] Whether the barcode can be recognized (read) can be confirmed by using a barcode reader (for example, the method described below).

[0129] Specific examples of different color printed parts include, for example, different colors 1 and 2, (i) when color 1 is the pattern and color 2 is the background, and (ii) when colors 1 and 2 are combined to form a pattern (for example, when colors 1 and 2 are adjacent to each other to form stripes, or when color 1 is a wavy pattern and color 2 is a wavy pattern following the wavy pattern of color 1), etc. A typical example of a different color printed part is the different color printed part of (i).

[0130] As described above, the printed portion may have one or two or more different color printed portions, and in particular may have two or more (plural) different color printed portions.

[0131] When there are multiple different color printed sections, the multiple different color printed sections may be the same or different color printed sections (for example, different color printed sections that differ in at least one type selected from color type, color combination, color range, clearance range, pattern, etc.).

[0132] For example, the multiple different color printed parts may have a combination of large widths (e.g., over 500 μm) and small widths (e.g., 500 μm or less). For convenience, the printed part may have two different different color printed parts, which are respectively called different color printed parts 1 and 2. To explain a specific example, there may be a case where the width of at least one of the different colors constituting the different color printed part 1 (e.g., the smaller width of the color forming the pattern) is over 500 μm, and the width of at least one of the different colors constituting the different color printed part 2 (e.g., the smaller width of the color forming the pattern) is 500 μm or less.

[0133] As described above, the visibility of the different color printed parts in the second embodiment (how unnoticeable the clearance is) can be adjusted according to the width of the color, so even if there is a combination of different color printed parts having colors with a large width and different color printed parts having colors with a small width, it is possible to form multiple different color printed parts that are efficient and easy to see across the entire printing substrate (overall).

[0134] The multiple different color printed parts usually include at least different different color printed parts. In order to efficiently suppress color bleeding and make the clearance less noticeable in such different different color printed parts, it is preferable to select the clearance of each different color printed part (selected according to the different color printed part) based on a specific index (color width, resolution, etc.).

[0135] In addition, the printed portion needs to have at least a different color printed portion (especially, a plurality of different different color printed portions), and may also have a non-different color printed portion (for example, a plain printed portion (a solid color only), or a printed portion having a pattern in one color).

[0136] [Manufacturing method] A printing substrate is obtained by forming (recording) a printing portion on a substrate.

[0137] Here, in the present invention, when printing different color printed sections (printed sections in which different colors are printed adjacent to each other), the printing is performed so that a clearance is generated between the different colors (or a clearance is provided between the different colors).

[0138] By printing in this manner, the above-mentioned printed base material can be obtained efficiently. In other words, bleeding in the different color printed portion can be suppressed or prevented. Therefore, such a method can be said to be a method for suppressing or preventing bleeding in the different color printed portion. As described above, even when printing is performed so that a clearance occurs (set so that a clearance is provided), different color inks may spread slightly toward each other's spaces. Even in such a case, if the size (width) of the clearance and the size (width) of the spread are the same, the different color inks will spread toward each other's spaces, but no bleeding will occur, and a different color printed area will be formed in which there is (apparently) no clearance between the different colors (different color printed area of ​​the first embodiment).

[0139] The printing method is not limited, but may in particular be an inkjet method (inkjet system).

[0140] In the inkjet method, examples of the inkjet method include a continuous type, an on-demand type (e.g., a piezo type, a thermal type, a valve type, etc.), etc. A typical example is the on-demand type (e.g., a piezo type).

[0141] The printing device can be selected depending on the printing method. For example, in the inkjet method, an inkjet printer may be used.

[0142] When clear ink is used in combination, a printer head having an ink chamber for ejecting the color inks and an ink chamber for ejecting the clear ink may be used.

[0143] Incidentally, printing (ejection of ink, etc.) may be performed while the substrate is being transported. In such a case, the conveying speed can be appropriately selected depending on the type of the base material, and may be, for example, 1 to 20 m / min (eg, 2 to 15 m / min, 3 to 12 m / min), etc.

[0144] In the case of printing (inkjet), the ink, resolution, and other aspects are as described above.

[0145] The amount of ink ejected per droplet (dot) may be, for example, 1 pL or more (e.g., 3 pL or more), preferably 5 pL or more (e.g., 7 pL or more), and more preferably 8 pL or more (e.g., 9 pL or more). The upper limit of the amount of ink ejected per droplet (dot) may be, for example, 50 pL, 30 pL, 20 pL, 15 pL, or the like.

[0146] This ejection amount is applicable to both color ink and clear ink.

[0147] In particular, when clear ink is used in combination, the total amount of ejection of the color ink and clear ink [ejection amount per drop (dot)] may be 1.1 or more, preferably 1.3 or more, and more preferably 1.5 or more (for example, 1.8 or more), when the ejection amount of the color ink is taken as 1, or may be 10 or less, 8 or less, 5 or less, 3 or less, etc.

[0148] When clear ink is used in combination, the amount of ink ejected (and therefore the amount of solvent in the printing area) is greater than when color inks are used alone; however, even with such a large amount of solvent, bleeding can be efficiently suppressed by printing with a clearance.

[0149] The ink may be ejected while the carriage (carriage having a head) is scanned (moved). In this case, the scanning direction may be, for example, perpendicular to the transport direction of the substrate. The scanning speed may be, for example, about 30 m / min or more (for example, 40 to 500 m / min), preferably 50 m / min or more (for example, 80 to 300 m / min), and more preferably 100 m / min or more (for example, 120 to 200 m / min).

[0150] As described above, when printing the different color printed parts, printing is performed (the printing device is set to print) so that a clearance is generated between the different colors. The form of the clearance is as described above, but the clearance set during such printing (sometimes referred to as a set clearance, etc.) may also be similar.

[0151] For example, the width of the clearance (set clearance, hereinafter the same applies to the clearance set during printing) may be selected from a range of, for example, approximately 2000 μm or less, and may be approximately 1500 μm or less, preferably 1000 μm or less, and more preferably 800 μm or less (e.g., 700 μm or less), and may be printed so that it is 600 μm or less (e.g., 500 μm or less, 400 μm or less, 350 μm or less). The lower limit of the set clearance width may be, for example, 3 μm, 5 μm, 7 μm, 10 μm, 15 μm, 20 μm, 30 μm, 50 μm, etc.

[0152] Specific examples of the set clearance width include 3 to 2000 μm, 10 to 1000 μm, 20 to 500 μm, 30 to 400 μm, 50 to 300 μm, and 100 to 200 μm.

[0153] As described above, due to the spreading of the ink, etc., the clearance (sometimes referred to as the actual clearance (as opposed to the set clearance)) in the formed different color printed portion may be smaller than the set clearance. Therefore, the width of the set clearance may be the same as the width of the actual clearance, or may be larger than the width of the actual clearance (desired clearance). When making the width larger in this way, the degree of the increase can be selected according to the expected spread of ink, the width of the desired clearance, and the like, and is not particularly limited.

[0154] In such a case, the width of the set clearance may be larger than the width of the actual clearance, for example, by about 1 μm or more [for example, 1.5 μm or more (for example, 2 to 300 μm), 2.5 μm or more (for example, 3 to 250 μm), 3.5 μm or more (for example, 4 to 200 μm), 4.5 μm or more (for example, 5 to 150 μm)]. Alternatively, the set clearance width may be more than 1 times the width of the actual clearance [for example, 1.001 times or more (for example, 1.005 times or more), 1.01 times or more (for example, 1.02 times or more), 1.05 times or more (for example, 1.07 times or more), 1.08 times or more, 1.1 times or more, etc.], or may be 5 times or less the width of the actual clearance (for example, 4 times or less, 3.5 times or less, 3 times or less, 2.5 times or less, 2 times or less, 1.8 times or less, 1.5 times or less, 1.3 times or less, 1.2 times or less, 1.1 times or less, 1.05 times or less, etc.).

[0155] As mentioned above, the amount of clearance can be selected depending on the range of different colors and the resolution of the print.

[0156] For example, when the different colors are colors 1 and 2, the width of color 1 or the width of color 2 (e.g., the smaller width of these, the width of the color forming the pattern) is A (μm), and the clearance width is B (μm), the value of B / A can be selected from a range of about 10 or less (e.g., 9.5 or less, 9 or less), and may be about 8 or less (e.g., 7.5 or less), preferably 7 or less (e.g., 6 or less), more preferably 5 or less (e.g., 4 or less), particularly 3 or less (e.g., 2.5 or less), or may be 2 or less (e.g., 1 or less, 0.8 or less, 0.5 or less, 0.3 or less, 0.1 or less), etc. Examples of the lower limit of the B / A value include 0.005, 0.01, 0.015, 0.02, 0.03, 0.05, 0.08, 0.1, 0.15, 0.2, 0.3, 0.4, and 0.5. Specific examples of B / A include 0.005 to 7, 0.01 to 5, 0.15 to 3, and 0.2 to 2.

[0157] Furthermore, when the printing resolution is X (dpi) and the number of pixels corresponding to the clearance width is Y, the value of X / Y [dpi / number (number of pixels)] may be adjusted to be, for example, approximately 20 to 800 (e.g., 22 to 700, 25 to 650, 28 to 600, 30 to 550, 40 to 500, 45 to 450).

[0158] Moreover, such X / Y values ​​may be selected according to the range of different colors.

[0159] For example, when the width of color 1 or the width of color 2 (e.g., the smaller of these, the width of the colors forming the pattern) is relatively small (e.g., 500 μm or less, 300 μm or less, 200 μm or less), the value of X / Y may not be too small (e.g., 50 or more, 80 or more, 100 or more, 120 or more, more than 120, 125 or more, etc.).

[0160] On the other hand, when the width of color 1 or the width of color 2 (e.g., the smaller of these, the width of the color forming the pattern) is relatively large (e.g., greater than 500 μm, 600 μm or more), the value of X / Y may not be too large (e.g., 200 or less, 150 or less, 120 or less).

[0161] In this way, by selecting (adjusting) the way in which the clearance is provided depending on conditions such as the color width and resolution, it is possible to efficiently form a natural different color printed area in which the clearance is not noticeable while suppressing bleeding between colors in the different color printed area.

[0162] As described above, the above printing conditions (clearance state, etc.) may be reflected in the same manner in the printed portion (different color printed portion) or may be reflected in different manners.

[0163] For example, even if printing is performed by an inkjet method, the dots in the printed area may be crushed, and the width of the clearance in the different color printed area may be smaller than the width of the clearance set during printing. As mentioned above, when at least one of the different color inks (especially both inks) spreads toward the space between the other colors, the width of the color set during printing [e.g., the width (length) corresponding to the number of pixels)] becomes larger in the printing area, which means that the actual clearance becomes smaller than the set clearance. In such a case, if the width of the color set during printing (hereinafter sometimes referred to as the set color width, etc.) is C1 and the width of the color in the different color printed part [hereinafter sometimes referred to as the actual color width, etc. (relative to the set color width)] is C2, the difference between them [C2 (actual color width C2) - C1 (set color width C1)] may be, for example, 0.5 μm or more (e.g., 0.8 μm or more, 1 μm or more, 1.5 μm or more, 2 μm or more, 2.5 μm or more, 3 μm or more, 3.5 μm or more, 4 μm or more, 4.5 μm or more, 5 μm or more), etc., or 300 μm or less (e.g., 280 μm or less, 250 μm or less, 200 μm or less, 180 μm or less, 150 μm or less, 120 μm or less, 100 μm or less, 80 μm or less, 70 μm or less, 50 μm or less, etc.).

[0164] After printing, a heat treatment (drying treatment) may be performed as necessary. The heat treatment can remove the solvent from the printed area. In addition, if the ink contains a crosslinking agent, crosslinking may be promoted during the heating (drying) process.

[0165] [Uses of printing materials] The printing substrate may be used as it is for various applications depending on the type and form of the substrate, or may be further molded (processed) as necessary to obtain a desired molded product.

[0166] For example, a printing substrate made of a plastic film (such as an inflation film) can be formed into a soft bag (medical soft bag) through a heat sealing process, a cutting process, a port (a port for filling the contents) attachment process, and the like.

[0167] The soft bag can then be converted into a soft bag (infusion bag) containing the contents by, for example, further undergoing a process of filling the bag with contents (infusion liquid, etc.) and a process of high-pressure sterilization (high-pressure shower sterilization), etc.

[0168] In this way, various loads are applied to the printing base material during the molding process after printing, and if the printed area (different color printed area) is not sufficiently fixed (recorded), it may fall off. For example, in the case of processing into the infusion bag, the printed portion (different color printed portion) is likely to fall off due to high pressure sterilization or the like. In addition, if the printed part is not fixed sufficiently, it will be prone to falling off when it comes into contact with chemicals (for example, alcohol such as ethanol).

[0169] In order to efficiently prevent such falling off, as mentioned above, it is advantageous to use clear ink in combination to ensure a sufficient amount of resin in the printed areas (different color printed areas). However, on the other hand, the use of clear ink tends to result in significant bleeding (color mixing) between colors in the different color printed areas, and ultimately in losses in the visibility and appearance of the printed areas.

[0170] However, according to the present invention, as described above, even when clear ink is used, bleeding in different color printed areas can be efficiently suppressed, and it is possible to efficiently achieve both strong printing (recording) (e.g., abrasion resistance, excellent adhesion, chemical resistance, etc.) required for medical soft bags and the like, and suppression of bleeding (and even making clearance less noticeable). EXAMPLES

[0171] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0172] The materials used are as follows:

[0173] Ink (color ink and clear ink) Inks 1 to 4 and 8 described in the examples of JP 2020-19180 A were prepared and used as color inks. Ink 9 described in the examples of JP 2020-19180 A was prepared and used as a clear ink. The composition of each ink is as follows: In the tables below, "parts" refers to parts by mass.

[0174] [Table 1]

[0175] <Antifoaming agent> DF110D: Product name "Surfynol DF110D", acetylene diol surfactant, manufactured by Nissin Scientific Industry Co., Ltd. <Surfactant> BYK348: Product name, silicone surfactant, manufactured by BYK Japan Co., Ltd. <Pigments> Black pigment: Carbon black Cyan pigment: CI Pigment Blue 15:3 Magenta pigment: CI Pigment Red 122 Yellow pigment: CI Pigment Yellow 150 · White pigment: CI Pigment White 6 <Resin> Joncryl 62J (product name, styrene-acrylic resin, manufactured by BASF Japan Ltd.) AQUACER539 (product name, modified paraffin wax emulsion for water-based systems, manufactured by BYK Japan Co., Ltd.)

[0176] The measurements and analyses were carried out as follows:

[0177] viscosity A rheometer (product name "MCR300" manufactured by Anton Paar) was used, and the measurement temperature was 32°C and the shear rate was 200 s -1 Measurements were taken at .

[0178] Wetting tension As a wetting reagent, we used a mixture for wetting tension testing (manufactured by Fujifilm Wako Pure Chemical Industries, etc.). A cotton swab was dipped into the mixture for wetting tension testing No. 35, and the liquid on the cotton swab was applied to the printed material. If the material was still wet after 2 seconds, the wetting tension was determined to be that value. A new cotton swab is dipped in the No. 45 wet tension test mixture and the same procedure is performed. Since it is repelled within 2 seconds, it is deemed to have a wet tension of 45 or less. Assuming that the wet tension value of the printed material is between 35 and 45, the maximum value at which the printed material remains wet for 2 seconds using a liquid with an appropriate wet tension value is determined to be the wet tension of the printed material.

[0179] Barcode recognition A Keyence SR2000 is placed about 20cm above the printed substrate (barcode portion) to capture and read the barcode. The SR2000 is adjusted so that it produces the closest verification values ​​(modulation, decodability, and defects) to those of the verification device on the calibration sheet. Recognition is possible when modulation is 25% or more, decodability is 37% or more, and defects are less than 30%.

[0180] Visual inspection The samples were visually observed from a distance of approximately 40 cm, and bleeding and clearance were judged according to the following criteria. A: Not confirmed at all B: Almost impossible to confirm C: Visible but not noticeable D: It is clearly visible The labeling judgment was performed by 30 people, and the most common judgment was recorded as the visual judgment result.

[0181] [Example 1] (Manufacturing of printing materials) The air was removed from the inner surface of a tube-shaped film (a laminated film of polybutylene terephthalate and olefin-based resin) that had been blown into a roll and rolled up, and the plain, transparent, strip-shaped film was sent to a buffer roll with the printed side (the polybutylene terephthalate side of the laminated film (wet tension 38 dyn / cm)) facing up.While being transported, a printed section was formed using the inkjet method.

[0182] That is, the tubular film was intended for use as a soft medical bag, and ink was ejected and printed onto the film under the conditions shown in the table below so as to form a plurality of different color printed portions.

[0183] [Table 2]

[0184] The colors of the different printed areas (the pattern and its background) were all printed along the horizontal direction of the film (i.e., the direction in which "Glucose-added electrolyte solution (maintenance fluid)" is printed in different printed area 1, "Infusion" is printed in different printed area 2, "1000 mL" is printed in different printed area 3, and the bars that make up the barcode in different printed area 4 are all aligned horizontally on the film).

[0185] The ink ejection head of the inkjet device moved (head scanning speed: 152 m / min) perpendicular (i.e. horizontal) to the film travel direction (vertical direction, film transport speed: 8 m / min), ejecting ink from the nozzles as it moved. Ink was ejected on the outbound and return paths of the ink ejection head. On the outbound path, clear ink was ejected immediately (almost simultaneously) after the colored ink was ejected, and on the return path, colored ink was applied immediately after the clear ink was ejected. This is due to the structure of the ejection head, as the nozzles are lined up in the direction of travel on the outbound path, with the nozzles ejecting color ink followed by the nozzles ejecting clear ink. Furthermore, the clear ink is ejected onto the color ink ejection area on the forward pass (and onto the area to be ejected on the return pass), and is not ejected onto the entire film (clear ink is not ejected onto areas where color ink is not ejected).

[0186] The film after the ink ejection was further transported while hot air was blown onto it to dry the printed surface, thereby obtaining the target product (a film provided with a printed portion including a plurality of different color printed portions).

[0187] (Evaluation of printing substrate) Unique Printing Part 1 Of the resulting film, a close-up photograph of the different color printed portion 1 is shown in FIG. 1, and a micrograph (20x magnification, black background) is shown in FIG.

[0188] The different color printed portion 1 has relatively small characters in color 1 (i.e., the width of each character in the string of characters "Sugar-Added Electrolyte Solution (Maintenance Fluid)"), but when visually inspected, there was absolutely no bleeding between color 1 and its background (Judgment A), and no clearance was observed (Judgment A). This was also evident from Figure 1, which can be considered a close-up view, and Figure 2, which is an enlarged photograph.

[0189] In the different color printed portion 1, as described above, the clearance set during printing is not noticeable at all, but when observed using a higher magnification microscope photograph, the presence of a slight clearance (gap between the character string and its background) was confirmed [approximately 78 μm vertically (approximately 0.92 times (1.8 pixels) the clearance set during printing, width 1 (350 μm), width 2 (175 μm), width B / width 1 = 0.22, width B / width 2 = 0.45, X / Y = 333), and approximately 42 μm horizontally (0.50 times (0.99 pixels) the clearance set during printing, width 1 (350 μm), width 2 (175 μm), width B / width 1 = 0.12, width B / width 2 = 0.24, X / Y = 606)].

[0190] Since color 1 is white, it was suggested that the white color is also related to the less noticeable clearance.

[0191] Unique Printing Part 2 Similarly, a close-up photograph of the different color printed portion 2 is shown in FIG. 3, and a micrograph (20x magnification, black background) is shown in FIG.

[0192] The different color printed portion 2 has letters of medium width (i.e., the width of each character of the character string "infusion") in color 1, but visual inspection revealed absolutely no bleeding between color 1 and its background (judgment A), and almost no clearance was observed (judgment B). In other words, even in the close-up photograph of Figure 3, no clear clearance could be confirmed between color 1 (character string) and the background, and it was only in the enlarged photograph of Figure 4 that a clear clearance could be recognized.

[0193] In the different color printed portion 2, as described above, the clearance set during printing is almost impossible to confirm with the naked eye, but the presence of the clearance was confirmed by microscopic observation [approximately 159 μm in the vertical direction (approximately 0.94 times (3.8 pixels) the clearance set during printing, width 1 (1636 μm), width 2 (630 μm), width B / width 1 = 0.097, width B / width 2 = 0.25, X / Y = 158), and approximately 116 μm in the horizontal direction (0.69 times (2.7 pixels) the clearance set during printing, width 1 (1636 μm), width 2 (630 μm), width B / width 1 = 0.071, width B / width 2 = 0.18, X / Y = 222)].

[0194] Unique Printing Part 3 Similarly, a close-up photograph of the different color printed portion 3 is shown in FIG. 5, and a micrograph (20x, white background) is shown in FIG.

[0195] The different color printed portion 3 has characters of a relatively large width [i.e., the width of each character (number, alphabet) of the character string "1000mL") in color 1, but visual inspection revealed absolutely no bleeding between color 1 and its background (judgment A), and almost no clearance was observed (judgment B). That is, even in the close-up photograph of Figure 5, a slight clearance could be confirmed in places between color 1 (character string) and the background, and it was only in the enlarged photograph of Figure 6 that a clear clearance could be recognized.

[0196] In the different color printed portion 3, as described above, the clearance set during printing is almost impossible to confirm with the naked eye, but the presence of the clearance was confirmed by microscopic observation [approximately 226 μm in the vertical direction (approximately 0.89 times (5.3 pixels) the clearance set during printing, width 1 (2388 μm), width 2 (2802 μm), width B / width 1 = 0.095, width B / width 2 = 0.081, X / Y = 113), and approximately 144 μm in the horizontal direction (0.57 times (3.4 pixels) the clearance set during printing, width 1 (2388 μm), width 2 (2802 μm), width B / width 1 = 0.060, width B / width 2 = 0.051, X / Y = 176)].

[0197] Unique Printing Part 4 Regarding the different color printed part 4 (barcode), no bleeding was observed between color 1 (barcode bars) and its background when visually inspected (Judgment A), and no clearance was observed (Judgment A). The fact that no clearance could be visually confirmed is likely related to the fact that the background color was white.

[0198] Regarding the different color printed portion 4, it was confirmed by the above-mentioned method whether it could be recognized as a barcode, and it was found to be recognizable.

[0199] Furthermore, when an enlarged photograph was taken and observed of the different color printed area 4, the presence of clearance was confirmed [approximately 154 μm vertically (approximately 0.91 times the clearance set during printing (3.6 pixels), width 1 (367 μm), width 2 (350 μm), width B / width 1 = 0.42, width B / width 2 = 0.44, X / Y = 167), and approximately 118 μm horizontally (approximately 0.7 times the clearance set during printing (2.8 pixels), width 1 (367 μm), width 2 (350 μm), width B / width 1 = 0.32, width B / width 2 = 0.34, X / Y = 214)].

[0200] (Infusion bag molding and evaluation) The printed film was heat-sealed at the four sides of the infusion bag (however, the port attachment position was not heat-sealed). After the heat-sealing process, the film was cut into an infusion bag, and a resin port was attached to the port attachment position by heat welding.

[0201] After the port attachment process, the contents (infusion) were filled through the port, a rubber stopper was attached to the port, and a protective film was attached to the port by heat fusion to protect the surface of the rubber stopper.Then, the bag was sterilized with a high-pressure shower to obtain an infusion bag.

[0202] The process up to high-pressure shower sterilization was carried out in-line.

[0203] During the molding process of the infusion bag, the different color printed parts 1 to 4 did not fall off. Furthermore, on the infusion bag after high-pressure shower sterilization, the different color printed parts 1 to 4 were rubbed strongly with a finger, but no falling off occurred. Furthermore, the different color printed parts 1 to 4 were wiped with a cloth soaked in ethanol, but again no peeling occurred. In this way, it was confirmed that the different color printed parts 1 to 4 were firmly printed on the infusion bag.

[0204] [Reference example 1] A printing substrate was obtained by printing in the same manner as in Example 1, except that printing was performed without leaving any clearance between the different color printed parts (color 1 and color 2 (background)) during printing. In the obtained film, in each of the different color printed portions 1 to 4, bleeding between color 1 and the background was clearly visible even at the visual inspection stage (Judgment D).

[0205] [Reference example 2] In Example 1, printing was performed in the same manner as in Example 1, except that no clear ink was used and no clearance was set between the different color printed areas (color 1 and color 2 (background)), and a printed substrate was obtained.

[0206] Although the different color printed parts 1 to 4 were slightly less than Reference Example 1, bleeding between colors was visually observed in all of them (Judgement C).

[0207] In addition, when an infusion bag was molded using the printed substrate in the same manner as in Example 1, the different color printed parts 1 to 4 were found to have fallen off in places, and when the bag was wiped with a cloth soaked in ethanol, almost all of the different color printed parts fell off.

[0208] [Example 2] Printed substrates were obtained with each clearance width in the same manner as in Example 1, except that the clearance width in the vertical direction of the different color printed portion 1 was changed to the value shown in the table below. Then, the different color printed portion 1 of each of the obtained printing substrates was visually evaluated in the same manner as in Example 1. The results are shown in the table below.

[0209] [Table 3]

[0210] [Example 3] Printing substrates were obtained with each clearance width in the same manner as in Example 1, except that the width of the lateral clearance of the different color printed portion 3 was changed to the value shown in the table below.

[0211] Then, the different color printed portion 3 of each of the obtained printing substrates was visually evaluated in the same manner as in Example 1. The results are shown in the table below.

[0212] [Table 4]

[0213] As is clear from the results in the table above, for colors with a relatively large width, even if the clearance width is somewhat large, by adjusting the value of X / Y, it is possible to form a different color printed area in which the clearance is less noticeable.

[0214] [Example 4] A printing substrate was obtained in the same manner as in Example 1, except that a single-layer polyethylene film (wetting tension of the printing surface: 35 dyn / cm) was used as the tubular film. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag.

[0215] [Example 5] A printing substrate was obtained in the same manner as in Example 1, except that a single-layer film of a mixed resin of polyethylene and polypropylene (wetting tension of the printing surface: 45 dyn / cm) was used as the tubular film. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag.

[0216] [Example 6] An ink according to Example 1 of JP2018-141066A was prepared. A printing substrate was obtained in the same manner as in Example 1, except that the obtained ink (cyan) was used instead of Ink 2. The obtained film showed similar trends to those in Example 1 in the different color printed parts 1 to 4 (particularly the different color printed parts 2 and 4), and in the molding and evaluation of the infusion bag.

[0217] [Example 7] A printing substrate was obtained in the same manner as in Example 1, except that inks 1 to 4 were used instead of black (FPG-BK), cyan (FPG-CY), magenta (FPG-MG), and yellow (FPG-YE) inks manufactured by Roland DG Corporation. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag.

[0218] [Example 8] A printing substrate was obtained in the same manner as in Example 1, except that the vertical resolution was changed to 400 dpi. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag.

[0219] [Example 9] A printing substrate was obtained in the same manner as in Example 1, except that the lateral resolution was changed to 200 dpi. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag.

[0220] [Example 10] A printing substrate was obtained in the same manner as in Example 1, except that the vertical resolution was changed to 300 dpi and the horizontal resolution was changed to 300 dpi. The obtained film showed the same tendency as in Example 1 in the molding and evaluation of the different color printed parts 1 to 4 and the infusion bag. [Industrial Applicability]

[0221] According to the present invention, a novel printing substrate and a method for producing the same can be provided.

Claims

1. A printing substrate having a printed portion on a substrate, the printed portion including a different color printed portion in which different colors are printed with a clearance therebetween; The width of the clearance of the different color printed portion is 0.1 to 0.99, assuming that the width of the clearance set in printing is 1; A printing substrate including a different color printed portion, in which when the different colors of the different color printed portion are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the width of the clearance is B (μm), the value of B / A is 8 or less.

2. A printing substrate having a printing portion on a substrate, The printed portion includes at least a different color printed portion in which different colors are printed adjacent to each other without causing bleeding, The width of the clearance of the different color printed portion is 0.1 to 0.99, assuming that the width of the clearance set in printing is 1; A printing substrate including a different color printed portion, in which when the different colors of the different color printed portion are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the width of the clearance is B (μm), the value of B / A is 8 or less.

3. 3. The printing substrate according to claim 1, wherein the printing surface of the substrate has a wetting tension of 30 to 50 dyn / cm.

4. The printing substrate according to any one of claims 1 to 3, wherein the substrate is a plastic film.

5. The printing substrate according to any one of claims 1 to 4, wherein the printing surface of the substrate is made of a polyester-based resin.

6. The printing substrate according to any one of claims 1 to 5, wherein the printed portion is printed by an inkjet method.

7. The printing substrate according to any one of claims 1 to 6, wherein the printed portion is formed with a water-based ink.

8. The printing substrate according to any one of claims 1 to 7, wherein the printed portion is formed with a color ink and a clear ink.

9. The printing substrate according to any one of claims 1 to 8, wherein the printed portion is formed with a water-based color ink and a water-based clear ink.

10. The printing substrate according to any one of claims 1 to 9, wherein the proportion of the resin in the printed portion relative to the total amount of the resin and the colorant is 20 mass % or more.

11. The printing substrate according to any one of claims 1 to 10, wherein the width of the clearance is 10 to 1500 µm.

12. The printing substrate according to any one of claims 1 to 11, comprising a different color printed portion, in which when the different colors are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the width of the clearance is B (μm), the value of B / A is 5 or less.

13. The printing substrate according to any one of claims 1 to 12, wherein the different color printed portion includes a different color printed portion having an X / Y value of 20 to 800, where X (dpi) is the printing resolution and Y is the number of pixels corresponding to the width of the clearance.

14. The printing substrate according to any one of claims 1 to 13, comprising a different color printed portion 1, in which the different colors are color 1 and color 2, the width of color 1 or the width of color 2 is 500 μm or less, and the printing resolution is X (dpi), and the number of pixels corresponding to the width of the clearance is Y, the value of X / Y is 50 or more.

15. The printing substrate according to claim 14, wherein in the different color printed portion 1, the width of color 1 or the width of color 2 is 400 μm or less, and the value of X / Y is 100 or more.

16. The printing substrate according to any one of claims 1 to 15, comprising a different color printed portion 2, in which the different colors are color 1 and color 2, the width of color 1 or the width of color 2 is greater than 500 μm, and the value of X / Y is 200 or less, where X is the printing resolution (dpi) and Y is the number of pixels corresponding to the width of the clearance.

17. 17. The printing substrate according to claim 16, wherein in the different color printed portion 2, the width of color 1 or the width of color 2 is 600 μm or more, and the value of X / Y is 150 or less.

18. The printing substrate according to any one of claims 1 to 17, wherein the different color printed portion comprises a different color printed portion 1 according to claim 14 or 15, and a different color printed portion 2 according to claim 16 or 17.

19. The printing substrate according to any one of claims 1 to 18, wherein the different color printed portion includes a different color printed portion, one of the different colors being white.

20. The printing substrate according to any one of claims 1 to 19, comprising a different color printed portion, in which the different colors are color 1 and color 2, color 1 being a pattern and color 2 being a background.

21. The printing substrate according to any one of claims 1 to 20, comprising a different color printed portion that can be recognized as a barcode or a two-dimensional code, in which the different colors are colors 1 and 2, color 1 being a barcode or two-dimensional code, and color 2 being a background.

22. The printed substrate according to any one of claims 1 to 21 for forming a soft medical bag.

23. A method for producing a printed substrate according to any one of claims 1 to 22, at least through a printing step of printing a printed portion on a substrate, wherein in the printing step, the different color printed portions are printed with a clearance provided between the different colors.

24. A method for suppressing or preventing bleeding between different colors in a different color printed portion in a printing substrate having a printed portion including a different color printed portion in which different colors are printed adjacent to each other on the substrate, the method including printing the different color printed portion by providing a clearance between the different colors in a printing process for printing the printed portion on the substrate.

25. 25. The method according to claim 23 or 24, wherein printing is by an inkjet method.

26. The method according to any one of claims 23 to 25, wherein in the printing step, printing is performed by ejecting color inks and clear ink.

27. The method according to any one of claims 23 to 26, wherein printing is performed so that the width of the clearance is 10 to 1500 µm.

28. The method according to any one of claims 23 to 27, wherein the clearance is provided so that the value of B / A is 8 or less when the different colors are colors 1 and 2, the width of color 1 or the width of color 2 is A (μm), and the width of the clearance is B (μm).

29. The method according to any one of claims 23 to 28, wherein the clearance is provided so that the value of X / Y is 20 to 800, where X is the printing resolution (dpi) and Y is the number of pixels corresponding to the width of the clearance.

30. A molded article of the printing substrate according to any one of claims 1 to 22.

31. 31. The molded article of claim 30, which is a soft medical bag.

Images