Printing apparatus and method for producing printed matter

Abstract

To evaluate the degree of solidification of printing ink in real time.SOLUTION: A printing apparatus 100 includes: a printing unit 20 that performs offset printing on a substrate 102 using four CMYK color printing inks; a solidification unit 30 that cures the printing ink printed on the substrate 102 by irradiating active energy rays from an active energy ray irradiation source 31 to obtain a printed matter; a detection unit 40 that detects the degree of solidification of the printing ink in the printed matter using an infrared absorption measurement method with a detector 41; and a determination unit 50 that determines, with reference to a calibration curve, whether the degree of solidification detected by the detection unit 40 has reached a specific standard.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a printing device and a method for producing a printed matter. [Background technology]

[0002] Printing is a manufacturing method for decorative sheet materials (hereafter referred to as "printed materials") and involves various processes. Among these, the process of drying and / or curing (hereafter referred to as "solidification") the printing ink to fix it to the substrate is a crucial process that determines the design and performance of the printed material. Traditionally, in the solidification process, a good solidification state has been achieved by supplying more than the necessary amount of energy. A good solidification state is an important factor in ensuring, for example, the prevention of loss of design due to offset or rubbing between paper surfaces, and the suppression of migration in food packaging materials.

[0003] Recently, with the growing trend to curb environmental destruction caused by the rapid increase in energy consumption, interest has been growing in the printing industry as well in reducing energy consumption, such as by controlling the excessive energy supply required for solidification and by bringing to market printing inks that can be solidified with less energy than conventional inks. For example, a method of measuring the coloration of leuco dyes has been proposed as a method for evaluating the degree of cure of active energy ray-curable resin compositions (Patent Document 1).

[0004] Label indicator products are also used to measure the amount of energy involved in solidification during printing. Examples include the ultraviolet detection material "UV Label" (registered trademark) manufactured by Nitto Giken Kogyo Co., Ltd., and the radiation label "XR Label" (registered trademark) for confirming blood irradiation manufactured by the same company. The former changes color from colorless to color when exposed to ultraviolet light, while the latter changes color from yellow to red when exposed to radiation. Furthermore, a product used to measure the amount of thermal energy is the temperature-indicating material "Thermo Label" (registered trademark) manufactured by the same company. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4572985 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when controlling the energy supply required for solidification, small unpredictable problems can result in less than the minimum amount of energy being supplied to some printed materials, raising concerns that the quality of the printed materials may not be guaranteed.

[0007] Leuco dyes used to measure coloration have low photostability, and when an active energy ray-curable resin composition containing a leuco dye is molded into a sheet and used, there are concerns about the accuracy of the degree of cure evaluation when used after long-term storage. Furthermore, when using a label indicator material to measure the amount of energy required for solidification during printing, the material must be attached to the printing equipment in advance, which poses challenges such as rewinding the base film and re-stacking the base paper after attachment. Real-time attachment during printing requires the introduction of attachment equipment and significant changes to the printing environment, making it unrealistic to introduce attachment equipment into existing printing machines.

[0008] After printing, the degree of solidification of the printed material is checked at regular intervals. If poor solidification is found in a specific area, it takes a great deal of effort to identify the area. Furthermore, if the area of ​​poor solidification is not identified, the largest area where poor solidification is thought to have occurred must be discarded in order to prevent the defective solidification from being distributed on the market, resulting in resource waste.

[0009] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a printing apparatus and a method for producing a printed matter that allow the degree of solidification of the printed matter to be confirmed in real time. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, the printing device according to the present application includes a printing unit that prints on a substrate with printing ink, a solidification unit that solidifies the printing ink printed on the substrate to obtain a printed matter, a detection unit that detects the degree of solidification of the printing ink in the printed matter, and a determination unit that determines whether the detection result of the degree of solidification satisfies a standard.

[0011] The printing unit may be composed of at least one of an offset printing machine, a gravure printing machine, a flexographic printing machine, an inkjet printing machine, a resin letterpress printing machine, a dry offset printing machine, and a digital printing machine. The solidifying unit may cure the printing ink by irradiating it with active energy rays. The active energy rays may include at least one of an electron beam and ultraviolet light.

[0012] The detection unit may detect the degree of solidification of the printing ink by non-contact measurement. The non-contact measurement may include infrared absorption measurement. The determination unit may determine the degree of solidification of the printing ink by referring to a calibration curve.

[0013] The printing apparatus may further include a paper feed unit that supplies the substrate and a paper discharge unit that stores the substrate that has passed through the solidification unit. The printing apparatus may further include a cutting unit that cuts the printed material after the solidification unit and before the paper discharge unit.

[0014] The method for producing a printed matter according to the present application includes the steps of printing a substrate with printing ink, solidifying the printing ink printed on the substrate to obtain a printed matter, detecting the degree of solidification of the printing ink in the printed matter in-line, and determining whether the detection result of the degree of solidification satisfies a standard.

[0015] The step of solidifying the printing ink may involve irradiating the printing ink with active energy rays to cure it. The active energy rays may be electron beams, and the printing ink may contain an electron beam-curable composition. The active energy rays may be ultraviolet rays, and the printing ink may contain an ultraviolet-curable composition.

[0016] The step of detecting the degree of solidification of the printing ink may detect the degree of solidification of the printing ink by non-contact measurement.The step of detecting the degree of solidification of the printing ink may detect the degree of solidification of the printing ink by infrared absorption measurement.

[0017] The printed matter may have a non-picture portion, and the step of detecting the degree of solidification of the printing ink may include detecting the degree of solidification of the printing ink in the non-picture portion. The step of determining may include determining the degree of solidification of the printing ink with reference to a calibration curve. The step of determining may include determining the degree of solidification of the picture portion based on the detected degree of solidification in the non-picture portion. [Effects of the Invention]

[0018] According to the present invention, the degree of solidification of printing ink can be evaluated in real time while a printed matter is being produced using a printing device, and the range in which the degree of solidification does not meet the standard can be quickly identified. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a block diagram illustrating a schematic configuration of a printing device. [Figure 2] 1 is a flowchart showing a series of steps in a method for producing a printed matter. [Figure 3] 1 is a graph showing an example of a calibration curve. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail. Note that the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[0021] The terms used in this embodiment are explained below. "(Meth)acryloyl" means acryloyl and / or methacryloyl (methacryloyl), and "(meth)acrylate" means acrylate and / or methacrylate (methacrylate). "Active energy rays" means energy rays such as ultraviolet rays and electron beams that have the property of causing chemical changes such as chemical reactions in the irradiated object.

[0022] In this embodiment, a numerical range indicated using "to" includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In multiple numerical ranges described in stages in this embodiment, the upper limit or lower limit of a numerical range in a certain stage can be arbitrarily combined with the upper limit or lower limit of a numerical range in another stage. Furthermore, unless otherwise specified, the materials and compounds exemplified in this embodiment may be used alone or in combination of two or more types.

[0023] 1 is a block diagram showing a schematic configuration of a printing apparatus 100 according to this embodiment. The printing apparatus 100 includes a paper feed unit 10 that supplies sheet-like substrate 102 such as paper in the order in which the substrate 102 advances through the printing apparatus 100, a printing unit 20 that prints printing ink on the substrate 102, a solidification unit 30 that solidifies the printing ink to obtain a printed product, a detection unit 40 that detects the degree of solidification of the solidified printing ink, a determination unit 50 that determines whether the detected degree of solidification has reached a standard, a cutting unit 60 that cuts the substrate 102 to predetermined dimensions, and a paper discharge unit 70 that stacks and stores the cut printed products 103.

[0024] In the printing apparatus 100, the paper supply unit 10 stores a roll 101 on which a sheet-like substrate 102 such as paper is wound, and pulls out and supplies the substrate 102 from the roll 101. The printing unit 20 is an offset rotary press that performs color printing on the sheet-like substrate 102, and is configured in the direction in which the substrate 102 advances: a black (K) printing unit 21, a cyan (C) printing unit 22, a magenta (M) printing unit 23, and a yellow (Y) printing unit 24. The black printing unit 21 has an impression cylinder 21a, an offset cylinder 21b, and a plate cylinder 21c, and an ink roller 21d and a water roller 21e are arranged around the plate cylinder 21c. The cyan printing unit 22, the magenta printing unit 23, and the yellow printing unit 24 have the same configuration as the black printing unit 21.

[0025] The solidification unit 30 irradiates the substrate 102, on which the printing ink has been printed in the printing unit 20, with active energy rays, such as electron beams, from the active energy ray irradiation source 31 to solidify the printing ink and obtain a printed product. The detection unit 40 detects changes in the properties of the printing ink solidified in the solidification unit 30 using a detector 41 in a non-contact manner, such as infrared absorption measurement. The evaluation unit 50 converts the detected amount obtained by the detection unit 40 into the degree of solidification of the printing ink by referring to a calibration curve. If the degree of solidification meets a specific standard, the result is judged as pass, and if it does not meet the standard, the result is judged as fail. The evaluation unit 50 may include input means such as buttons and display means such as a display for setting the specific standard and displaying the evaluation results. The evaluation unit 50 may also include a memory unit for storing data on the calibration curve and the specific standard. The cutting unit 60 cuts the substrate 102 to a predetermined size using a blade 61. The paper discharge unit 70 stacks and stores the printed products 103 cut by the cutting unit. The cutting unit 60 may be located behind the paper discharge unit 70 .

[0026] The printing apparatus 100 of this embodiment is shown as an example, and the present invention is not limited to this configuration. While the printing unit 20 is shown as an offset rotary press that prints four colors on one side of the substrate 102, the printing method is not limited to offset printing. Instead, it can be applied to a sheet-fed press instead of a rotary press using roll paper. Furthermore, it is not limited to single-sided four-color printing; it can also be applied to double-sided printing, monochrome printing, or printing with four or more colors. It can also be applied to printing varnishes that do not contain color pigments. The solidification of the printing ink in the solidification unit 30 is not limited to irradiation with active energy rays such as electron beams from the active energy ray irradiation source 31, but can also be achieved by other methods such as heating. The detection unit 40 can measure changes in the properties of the printing ink using other methods, not just infrared absorption measurement, and the detector 41 can be used to measure the properties of the printing ink by contacting the printing ink rather than non-contact.

[0027] 2 is a flowchart showing a series of steps in a method for producing a printed matter in the printing device 100. The method for producing a printed matter will be described below with reference to this flowchart.

[0028] In the paper feeding process of step S1, a sheet-like substrate 102 is fed from the paper feeding unit 10. The paper feeding unit 10 pulls out the substrate 102 from the roll 101 and continuously feeds it downstream. A predetermined tension is applied to the substrate 102, and the substrate 102 is fed downstream at a predetermined speed. Note that the paper feeding unit 10 may feed the substrate 102 having a predetermined dimension in a sheet form, instead of continuously feeding the substrate 102 wound around the roll 101.

[0029] <Base material> The substrate 102 may be any sheet-like material on which printing ink can be printed. Examples of paper sheet-like materials include ordinary paper and cardboard, and the thickness is not particularly limited. The surface of the paper sheet-like material may be vapor-deposited with a metal such as aluminum to impart a design. Furthermore, the paper substrate may be surface-coated with acrylic resin, urethane resin, polyester resin, polyolefin resin, or other resin, and may further be surface-treated by corona treatment or the like. Specific examples of surface-treated paper substrates include coated paper and art paper.

[0030] Examples of resin sheet-like materials include polyolefin substrates such as polyethylene and polypropylene, polyester substrates such as polyethylene terephthalate and polylactic acid, polycarbonate substrates, polystyrene-based substrates such as polystyrene, AS resin and ABS resin, nylon substrates, polyamide substrates, polyvinyl chloride substrates, polyvinylidene chloride substrates, cellophane substrates, paper substrates, aluminum substrates, and film-like substrates made from composite materials of these.

[0031] Alternatively, a vapor-deposited substrate in which an inorganic compound such as silica, alumina, or aluminum is vapor-deposited onto a film substrate can be used as the substrate 102. Furthermore, the vapor-deposited surface may be coated with polyvinyl alcohol or the like.

[0032] The surface of the substrate 102 to be printed (the surface in contact with the printing layer) is preferably subjected to an adhesion-enhancing treatment. Specific examples of adhesion-enhancing treatments include corona discharge treatment, ultraviolet / ozone treatment, plasma treatment, oxygen plasma treatment, and primer treatment. Furthermore, if sufficient adhesion cannot be obtained with a polyethylene terephthalate substrate, surface treatments such as acrylic coating treatment, polyester treatment, and polyvinylidene chloride treatment may be applied.

[0033] In the printing process of step S2, a printed matter is obtained by printing inks in the printing unit 20 onto the substrate 102 supplied from the paper feed unit 10. The printing unit 20 of the printing device 100 is configured, for example, as an offset printing rotary press that performs four-color printing. In the printing unit 20, a black printing unit 21, a cyan printing unit 22, a magenta printing unit 23, and a yellow printing unit 24 print on the substrate 102 with printing inks of their respective colors to obtain a color printed matter.

[0034] <Print> Printing is not limited to offset printing, and can be performed using known printing methods such as gravure printing, flexographic printing, inkjet printing, resin letterpress printing, dry offset printing, and digital printing, or a combination of these. The printing speed, i.e., the speed at which the substrate 102 advances through the printing device 100, is not particularly limited, but is preferably 10 m / min or higher, more preferably 30 m / min or higher, even more preferably 50 m / min or higher, and even more preferably 80 m / min or higher. By printing at a speed higher than this, the time from the printing process of step S2 to the next solidification process of step S3 can be shortened, and changes in properties before and after irradiation due to causes other than solidification can be suppressed.

[0035] <Printing ink> The printing ink is not limited as long as it is a liquid that can be printed on a substrate and retains the property of solidifying after the solidification step described below. For example, an oil-based ink for rotary printing may contain a solvent that is sufficient for heat setting. For example, an oil-based ink for sheet-fed printing may contain an unsaturated fatty acid that is sufficient for heat setting. For example, an active energy ray-curable ink for active energy ray irradiation printing may contain a radical polymerizable compound.

[0036] The radical polymerizable compound is a compound having a radically polymerizable ethylenically unsaturated bond, and may be any compound having at least one ethylenically unsaturated bond in the molecule, including those having chemical forms such as monomers, oligomers, and polymers. The radical polymerizable compound may be used alone or in combination of two or more. Examples of radical polymerizable compounds include unsaturated carboxylic acids such as (meth)acrylic acid, itaconic acid, and maleic acid, and salts thereof, anhydrides having an ethylenically unsaturated group, acrylonitrile, styrene, and various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes. More specifically, the radical polymerizable compound includes 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, β-carboxyethyl (meth)acrylate, 4-tert-butylcyclohexanol (meth)acrylate, tetrahydrofurfuryl acrylate, alkoxylated tetrahydrofurfuryl acrylate, caprolactone (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isodecyl (meth)acrylate, 3,3,5-trimethylcyclohexanol (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (oxyethyl) (meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, benzyl (meth)acrylate, EO-modified (2) nonylphenol acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate, acryloylmorpholine, N-vinylcarbazole, 1-vinylimidazole, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, N-vinylformamide, and other monofunctional radical polymerizable compounds;1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol (200) di(meth)acrylate, polyethylene glycol (300) di(meth)acrylate acrylate, polyethylene glycol (400) di(meth)acrylate, polyethylene glycol (600) di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, EO modified (2) 1,6-hexanediol di(meth)acrylate, PO modified (2) neopentyl glycol di(meth)acrylate, (neopentyl glycol modified) trimethylolpropane di(meth)acrylate, dimethylol tricyclode Bifunctional radical polymerizable compounds such as bisphenol A di(meth)acrylate, EO-modified (4) bisphenol A di(meth)acrylate, PO-modified (4) bisphenol A di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, and tris(2-hydroxyethyl)isocyanurate di(meth)acrylate; trimethylolpropane tri(meth)acrylate, EO-modified (3) trimethylolpropane tri(meth)acrylate, and PO-modified (3) trimethylolpropane tri(meth)acrylate trifunctional radical polymerizable compounds such as acrylate, ε-caprolactone-modified tris-(2-acryloxyethyl)isocyanurate, ethoxylated isocyanuric acid tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, and pentaerythritol tri(meth)acrylate; tetrafunctional radical polymerizable compounds such as pentaerythritol tetra(meth)acrylate and ditrimethylolpropane tetra(meth)acrylate; and pentafunctional radical polymerizable compounds such as dipentaerythritol penta(meth)acrylate;and dipentaerythritol hexa(meth)acrylate and other hexafunctional radical polymerizable compounds. Examples of the radical polymerizable compound that can be used include unsaturated urethanes such as urethane acrylates, such as aliphatic urethane acrylates and aromatic urethane acrylates; unsaturated polyesters such as polyester acrylates; unsaturated polyethers such as polyether acrylates; and epoxy acrylates.

[0037] Printing inks may contain the substances listed below, but those with properties that suppress or inhibit detection in the detection step of step S4 described below are undesirable. For example, if colorimetric measurement is used to detect the degree of solidification of printed matter, the inclusion of color pigments may reduce the hue difference before and after solidification, thereby inhibiting colorimetric detection. For example, if infrared absorption measurement is used to detect the degree of solidification of printed matter, the inclusion of substances with infrared absorption wavenumbers at infrared measurement wavenumbers, such as C=C stretching vibrations and CH out-of-plane bending vibrations, which have relatively large peak intensity differences before and after solidification, can lead to a decrease in the accuracy of the calibration curve. For example, if optical interference measurement is used to detect the degree of solidification of printed matter, the inclusion of substances that impart irregularities to the surface of the printed matter can lead to a decrease in the accuracy of the calibration curve. For example, if luminescence measurement is used to detect the degree of solidification of printed matter, the inclusion of substances that emit strong light regardless of the degree of solidification, such as fluorescent brighteners that absorb ultraviolet light, can lead to a decrease in the accuracy of the calibration curve. In either case, accuracy can be improved by, for example, measuring the background or using multivariate analysis. In one embodiment, luminescence refers to a phenomenon in which part of the energy released during transition from an excited state to a ground state becomes light, and includes fluorescence and phosphorescence.

[0038] Printing inks can contain extender pigments. The use of extender pigments can adjust the fluidity and coating strength of the printing ink and prevent paper smearing during printing. Printing inks can contain resins. Resins can provide the printing ink with appropriate elasticity and contribute to the dispersion of color pigments. Printing inks can contain photopolymerization initiators. These initiators polymerize and polymerize radically polymerizable compounds, particularly when the active energy rays are ultraviolet. Printing inks can contain organic and / or inorganic pigments. The use of color pigments can impart color to printed materials, and the use of multiple printing inks with different color pigments can produce colorful printed materials. Printing inks can optionally contain colorants, waxes, leveling agents, antistatic agents, surfactants, defoamers, polymerization inhibitors, UV absorbers, antioxidants, antioxidants (preservatives), and the like, as needed.

[0039] The printing ink may contain a thermochromic material or a photochromic material. In one embodiment, these materials refer to materials that change color or emit light due to a change in molecular structure or zwitterionization when supplied with energy such as heat or active energy rays. For example, color-changing materials include leuco dyes such as leuco crystal violet and 4,4',4''-tris-di-β-hydroxyethylaminotriphenylacetonitrile (HHEVC). Light-emitting materials include spiropyran compounds such as 1,3,3-trimethylindolinobenzopyrilospiran, diarylethene compounds, and azobenzene compounds.

[0040] Photopolymerization initiators can also be used as the luminescent material. Any luminescent photopolymerization initiator can be used, and is not particularly limited. Examples of suitable photopolymerization initiators include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, 2-(dimethylamino)-2-(4-methylbenzyl)-1-(4-morpholinophenyl)butan-1-one, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4-diethylthioxanthen-9-one, 4,4'-bis(diethylamino)benzophenone, and Esacure One (manufactured by iGM).

[0041] In the solidification process of step S3, the printing unit 20 prints the printing ink onto the substrate 102 supplied from the paper feed unit 10. In the solidification unit 30, the substrate 102 on which the printing ink has been printed in the printing unit 20 is irradiated with active energy rays from the active energy ray irradiation source 31 to solidify the printing ink, thereby obtaining a printed matter comprising the substrate 102 and the solidified printing ink. The printing ink may also be solidified by drying, in which case a cooling step may be provided to cool the printed matter whose temperature has been raised by drying.

[0042] <Solidification> In one embodiment, solidification refers to the solidification of printing ink by thermal energy, active energy ray energy, or the like. Solidification can be broadly divided into drying and curing. In one embodiment, drying refers to the solidification of printing ink by a method such as oxidative polymerization, evaporation drying, or penetration drying, and curing refers to the solidification of printing ink by the polymerization of the (meth)acryloyl group of a radically polymerizable compound caused by active energy rays.

[0043] <Printed material> In one embodiment, the printed matter is a sheet-like material containing a substrate and a solidified printing ink (hereinafter referred to as a coating film). The coating film is preferably a thin film having a thickness of several hundred nanometers to several tens of micrometers. If the coating film is thin, the detected value may be small, and the detection accuracy may decrease. If the coating film is thick, the degree of solidification may differ between the substrate side and the outermost surface in the solidification process of step S3.

[0044] In the detection process of step S4, in order to detect in-line the degree of solidification of the printing ink solidified into the coating film in step S4, the properties of the printing ink are measured by a detector 41 provided in the detection unit 40. Since the properties of the printing ink change depending on the degree of solidification, the amount of change is output as the detected amount. The detector 41 may be a non-contact detector such as an infrared spectrometer, fluorescence spectrometer, or Raman scattering spectrometer, or it may be a detector that comes into contact with the printing ink.

[0045] <Degree of solidification> The degree of solidification is the degree of dryness or hardening of the coating film formed by solidifying the printing ink in the solidification section 30. The degree of dryness refers to the stickiness of the coating film, and the degree of hardening refers to the degree of polymerization of the (meth)acryloyl group of the radical polymerizable compound.

[0046] <inline> The inline process is the process in the printing apparatus 100 from when the substrate 102 is supplied from the paper feed unit 10 to when it reaches the paper discharge unit 70. Although not included in the printing apparatus 100 shown in FIG. 1, the inline process can include devices such as an automatic paper folder and an inverting machine. While these non-printing devices are not particularly limited, the number of devices between the printing unit 20, which performs the printing process of step S1, and the solidification unit 30, which performs the solidification process of step S3, is preferably two or less, and more preferably one or less. Having one or less device can shorten the time from the end of the printing process of step S1 to the start of the solidification process of step S2, and can suppress changes in the properties of the printing ink due to causes other than solidification.

[0047] <Detection> Detection involves detecting changes in properties that occur as printing ink solidifies. For example, detecting the difference in hue between the printing ink and the coating due to solidification. Another example is detecting the decrease in absorption bands due to C=C bonds and the broadening or sharpening of other absorption bands due to curing. Another example is detecting changes in interference fringes due to solidification. Another example is detecting changes in light emission, including fluorescence and phosphorescence, due to solidification.

[0048] These detections can be performed on the patterned portion of the printed matter or on the non-patterned portion. Here, the patterned portion refers to the portion that imparts design and performance to the printed matter. The non-patterned portion refers to the portion that imparts performance without placing emphasis on design, such as a portion printed with a color patch or trim mark. These observations are preferably performed on the non-patterned portion. When performed on the non-patterned portion, changes in properties that occur due to curing can be easily detected without being hindered by the printing ink that is applied intricately for the purpose of design, and quantitative observation allows the degree of solidification to be quantitatively observed.

[0049] The determination step of step S5 determines whether the degree of solidification of the printing ink satisfies a specific standard based on the detection results obtained in the detection step of step S4. For example, as shown in FIG. 3, the determination unit S5 may convert the detected amount into the degree of solidification of the printing ink by referring to a calibration curve showing the correspondence relationship between the amount of detection obtained by the detection unit S4 and the degree of solidification of the printing ink. The determination unit S5 may then determine that the solidified ink of the printing ink has reached a predetermined standard value and that the solidified ink has not reached the standard value. The determination unit 50 may prepare a calibration curve in advance showing the relationship between the detected amount and the degree of solidification of the printing ink in the picture area. The determination unit 50 may also prepare a calibration curve in advance showing the relationship between the detected amount in the non-picture area and the degree of solidification of the printing ink in the picture area. In this case, the determination unit 50 may convert the detected amount in the non-picture area into the degree of solidification of the printing ink in the picture area by referring to the calibration curve, and then determine the degree of solidification of the printing ink.

[0050] <Specific criteria> The specific standard is calculated by statistical analysis and is a detection result for achieving a certain degree of solidification. In one embodiment, the statistical processing may be univariate analysis or multivariate analysis. In one embodiment, it is preferable to create a calibration curve in advance by statistical processing to show the correlation between the degree of solidification and the detection result. In this case, the degree of solidification can be quantitatively evaluated.

[0051] In the paper discharge process of step S6, the substrate 102 that has undergone a series of processes in the printing apparatus 100 is received and stored. After the detection process of step S5 in the detection unit 40, the substrate 102 is cut to a predetermined size by the blade 61 provided in the cutting unit 60 and then sent to the paper discharge unit 70. The paper discharge unit 70 stacks and stores the substrates 102 cut to the predetermined size, i.e., the printed matter 103, and discharges them all at once. As described above, the degree of solidification of the printing ink detected in-line by the detection unit 40 is determined by the determination unit 50 to see if it meets specific standards, so it is clear whether the printed matter 103 stored in the paper discharge unit 70 has passed or failed.

[0052] As described above, the printing device 100 of this embodiment incorporates a detection unit 40 that detects the degree of solidification of the printing ink and a judgment unit 50 that determines whether the degree of solidification meets a specific standard, thereby making it possible to evaluate the degree of solidification of the printing ink in real time and quickly identify the range of printed matter whose degree of solidification does not meet the standard.

[0053] Furthermore, in the method of manufacturing a printed matter in this embodiment, a detection process S4 for detecting the degree of solidification of the printing ink and a determination process S5 for determining whether the degree of solidification meets a specific standard are incorporated in-line into the series of steps for manufacturing the printed matter in the method of manufacturing a printed matter in the printing device 100. This makes it possible to evaluate the degree of solidification of the printing ink in real time while manufacturing the printed matter in the printing device 100, and quickly identify the range of printed matter whose degree of solidification does not meet the standard. [Explanation of symbols]

[0054] 10 Paper feed section 20 Printing Department 21a impression cylinder 21b Offset body 21c plate cylinder 21d ink roller 21e Water Roller 30 Solidification section 31 Active energy ray irradiation source 40 Detector 41 Detector 50 Judgment section 60 Cutting section 70 Paper output section 100 Printing device 102 Base material

Claims

1. a printing unit that prints on the substrate with printing ink; a solidification unit that solidifies the printing ink printed on the substrate to obtain a printed matter; a detection unit that detects the degree of solidification of the printing ink on the printed matter; a determination unit that determines whether the detection result of the solidification degree satisfies a standard; 1. A printing device comprising:

2. 2. The printing device according to claim 1, wherein the printing section comprises at least one of an offset printing machine, a gravure printing machine, a flexographic printing machine, an inkjet printing machine, a resin relief printing machine, a dry offset printing machine, and a digital printing machine.

3. The printing apparatus according to claim 1 , wherein the solidifying unit cures the printing ink by irradiating it with active energy rays.

4. 4. The printing apparatus according to claim 3, wherein the actinic energy rays include at least one of an electron beam and an ultraviolet ray.

5. 2. The printing apparatus according to claim 1, wherein the detection unit detects the degree of solidification of the printing ink by non-contact measurement.

6. 6. The printing apparatus of claim 5, wherein the non-contact measurement includes an infrared absorption measurement.

7. 2. The printing apparatus according to claim 1, wherein the determining unit determines the degree of solidification of the printing ink by referring to a calibration curve.

8. a paper feed unit that supplies the substrate; a paper discharge section that stores the substrate that has passed through the solidification section; The printing device of claim 1 further comprising:

9. 9. The printing apparatus according to claim 8, further comprising a cutting unit that cuts the printed matter, located after the solidifying unit and before the paper discharge unit.

10. printing the substrate with a printing ink; a step of solidifying the printing ink printed on the substrate to obtain a printed matter; detecting the degree of solidification of the printing ink in the printed matter in-line; a step of determining whether the detection result of the solidification degree satisfies a standard; A method for producing a printed matter, comprising:

11. The method for producing a printed matter according to claim 10, wherein the step of solidifying the printing ink comprises irradiating the printing ink with active energy rays to cure the printing ink.

12. The method for producing a printed matter according to claim 11, wherein the actinic energy rays are electron beams, and the printing ink contains an electron beam curable composition.

13. The method for producing a printed matter according to claim 11, wherein the actinic energy rays are ultraviolet rays, and the printing ink contains an ultraviolet-curable composition.

14. 11. The method for producing a printed matter according to claim 10, wherein the step of detecting the degree of solidification of the printing ink detects the degree of solidification of the printing ink by non-contact measurement.

15. 15. The method for producing a printed matter according to claim 14, wherein the step of detecting the degree of solidification of the printing ink detects the degree of solidification of the printing ink by infrared absorption measurement.

16. 11. The method for producing a printed matter according to claim 10, wherein the printed matter has a non-design portion, and the step of detecting the degree of solidification of the printing ink includes detecting the degree of solidification of the printing ink in the non-design portion.

17. The method for producing a printed matter according to claim 10, wherein the determining step determines the degree of solidification of the printing ink by referring to a calibration curve.

18. 18. The method for producing a printed matter according to claim 17, wherein the printed matter has a non-pattern portion, the step of detecting the degree of solidification of the printing ink detects the degree of solidification of the printing ink in the non-pattern portion, and the step of determining determines the degree of solidification of the pattern portion of the printed matter based on the detected degree of solidification in the non-pattern portion.

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