JP6288944B2 - Inkjet print - Google Patents

Description

  The present invention relates to an inkjet printed matter in which a pattern is expressed on the surface of a substrate having moisture absorption / release properties.

Techniques relating to members having moisture absorption / release properties have been proposed. For example, Patent Document 1 discloses a non-combustible humidity-control building material that is excellent in moisture absorption and release, moisture permeability, and has sufficient strength that can be used as a building material, and is also excellent in design. This humidity conditioning building material is a molded product produced by a carbonic acid curing reaction, and is composed of a molded product whose main components are calcium carbonate and amorphous silica. The humidity-conditioning building material has a specific surface area of 80 to 250 m ² / g by nitrogen gas adsorption method, an average pore diameter of 1.5 to 30.0 nm, and a colored portion to which a pigment is added. The colored part contains 2.0% by weight or less of a pigment having an average particle size of 2.0 μm or less based on the total weight of the colored part. In the production of humidity-controlled building materials, wet powder in which 2.4 parts by weight or less of pigment having an average particle size of 2.0 μm or less is mixed with 100 parts by weight of powder of calcium silicate hydrate as a main component is press-molded, Cured and cured in a carbon dioxide atmosphere. A calcium silicate hydrate powder having a lightness of L ^* C ^* h color system and L ^* of 60 or more is used. Patent Document 2 discloses a method for producing a designable building material.

  Furthermore, the applicant has also proposed a humidity control building material and a recording method thereof in Patent Document 3. Patent Document 3 describes the following regarding a base material for forming a humidity-control building material. That is, as a substrate, moisture absorption and desorption that acts to absorb and reduce humidity when the humidity in the room becomes high, and to release moisture and raise humidity when the room becomes dry and humidity becomes low. A molded body containing an inorganic powder having a function is preferable for image recording, and examples of the inorganic powder include siliceous powder, silica gel, diatomaceous earth, activated clay, zeolite, bentonite, montmorillonite, sepiolite, and the like. It is described. In addition, these inorganic powders have a large number of fine pores with a size of 1 to several tens of nanometers formed on the entire surface, and water molecules in the air are taken into the pores or water molecules from the pores. It is described that moisture absorption and desorption is performed by releasing the air into the air.

  In addition, Patent Document 4 discloses a humidity control wallpaper. This humidity control wallpaper has a three-layer structure of a moisture absorbing / releasing layer, and a front sheet and a back sheet sandwiching the moisture absorbing / releasing layer. The moisture absorbing / releasing layer is mainly composed of moisture absorbing / releasing fibers and heat-fusible fibers. The content of the heat-fusible fiber in the moisture absorbing / releasing layer is 10 to 70% by weight. The top sheet has moisture permeability or breathability. In the humidity control wallpaper, a cosmetic sheet having moisture permeability or air permeability may be further laminated on the surface of the surface sheet.

JP 2002-29804 A JP 2004-305834 A JP 2011-26871 A JP 2005-220449 A

  According to the ink jet recording apparatus, a high quality pattern can be expressed on the surface of the substrate. In the case where moisture absorption / release properties are imparted to an inkjet printed matter having a pattern expressed on the surface by the inkjet recording apparatus, the moisture absorption / release property is obtained by, for example, using a member having moisture absorption / release properties on a substrate forming the inkjet printed matter. Realized. If the inventor can further enhance the three-dimensional effect on the pattern expressed on the surface in the inkjet print that can realize a suitable design property with a high-quality pattern, the known inkjet print having a moisture absorption / release property I thought it could be differentiated. Therefore, the inventor has studied a technique capable of expressing a three-dimensional effect in a pattern expressed on the surface of an ink-jet print having moisture absorption / release properties.

An object of this invention is to provide the inkjet printed matter which has the designability which can give a three-dimensional effect to the user who visually recognized the pattern expressed on the surface of the base material which has moisture absorption / release property.

One aspect of the present invention is a moisture-absorbing / releasing ink-jet print having a pattern on the surface, the moisture-absorbing / releasing substrate having a rectangular outer shape, and the pattern represented on the surface of the substrate. A plurality of ink dots formed in a partial region of the surface of the base material, and the pattern represented on the surface of the base material by the plurality of ink dots is a unit as the brightness decreases by increasing the number of ink dots per area, the Heidelberg Gradient to change brightness continuously in a specific direction along a predetermined two sides facing each other of the base includes a plurality in the specific direction, In the gradation, the lightness difference ΔL ^* between the maximum value and the minimum value of the lightness L ^* in the L ^* a ^* b ^* color system is set in the range of 8 to 12, and L ^* a ^{* on} the surface of the base material ^. b ^* brightness in color system ^* Is a lightness L ^* of the maximum value, in the plurality of ink dots by pattern expressed on the surface of the substrate, the lightness L ^* in the region of the maximum value of the first gradient of the plurality of gradation And the region of the lowest lightness L ^* of the second gradation of the plurality of gradations is an inkjet printed matter that is continuously arranged in the specific direction.

According to this, the pattern which has a suitable three-dimensional effect on the surface of an inkjet printed matter can be expressed. By forming ink dots in a partial area of the surface of the base material, it becomes possible to secure a region where the background surface of the base material is exposed on the surface of the ink jet printed matter, and to maintain moisture absorption and desorption in the ink jet printed matter. be able to. The “surface of the substrate” is the background surface of the substrate. A gradation can be formed using the background surface of the base material to express a pattern having a three-dimensional effect. Moisture absorption and desorption can be maintained in a region having the highest lightness L ^* in gradation .

The inkjet printed matter is a building interior material or wallpaper, and the plurality of ink dots are measured in accordance with a moisture absorption / release test method for building materials defined in JIS A 1470-1: 2002 as follows. The difference between the moisture absorption amount obtained by subtracting the moisture absorption amount of the surface of the inkjet printed matter from the moisture absorption amount of the surface of the substrate in the substrate and the inkjet printed matter in the state of performing the procedure 1 and the procedure 2 of 2.5 g / M ² or less, and the base material and the inkjet printed matter in the state in which the following measurement method, step 1, step 2 and step 3 were performed in accordance with the moisture absorption / release test method, the surface of the base material The difference in moisture release rate obtained by subtracting the moisture release rate of the surface of the inkjet print from the moisture release rate is 4.8% or less. There.
(Measuring method)
Procedure 1 : Curing the substrate and inkjet printed material for 48 hours in an environment at a temperature of 23 ° C. and a humidity of 50% Procedure 2: After the procedure 1, the substrate and inkjet printed material are placed in an environment of a temperature of 23 ° C. and a humidity of 75% Place for 12 hours Step 3: After Step 2, place the substrate and inkjet print in an environment of temperature 23 ° C. and humidity 50% for 12 hours. According to this, to obtain moisture absorption and moisture release equivalent to the substrate Can do.

ADVANTAGE OF THE INVENTION According to this invention, the inkjet printed matter which has the designability which can give a three-dimensional effect to the user who visually recognized the pattern expressed on the surface of the base material which has moisture absorption / release property can be obtained.

It is a front view which shows an example of the inkjet printed matter by which the pattern containing gradation was expressed on the surface. It is the schematic which shows the state on the base-material surface of the ink dot which forms the gradation contained in a pattern, and is sectional drawing which cross-sectioned the inkjet printed matter in the position corresponding to the SS line | wire shown in FIG. 1 is a perspective view illustrating a schematic configuration of an ink jet recording apparatus. It is a figure which shows the evaluation result of the hygroscopic property and moisture release property of a base material and an inkjet printed matter.

  Embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the configurations described below, and various configurations can be employed in the same technical idea. For example, some of the configurations shown below may be omitted or replaced with other configurations. Other configurations may be included.

<Inkjet prints>
The inkjet printed matter 10 having moisture absorption / release properties will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the inkjet printed material 10 is a printed material having moisture absorption and desorption properties with a pattern on the surface. The inkjet printed product 10 is a member that forms various products that require design properties. For example, the inkjet printed product 10 is an interior material such as a vehicle or a building, or a wallpaper. The inkjet printed product 10 is a member that forms various interiors such as a screen in a roll curtain or a board that forms a partition or furniture.

As shown in FIG. 2, the inkjet printed product 10 includes a base material 12 and a plurality of ink dots 14. The base material 12 has moisture absorption / release properties. Absorbing definitive to various members which are formed by the inkjet printed matter 10 wet is achieved by moisture sorption with the substrate 12. Many fine pores are formed on the surface of the substrate 12. The surface of the substrate 12 on which the ink dots 14 are formed is the background surface of the substrate 12. The surface (background surface) of the base material 12 is plain (for example, white or beige) of a predetermined color. The color of the surface of the substrate 12 is appropriately determined in consideration of various conditions. The hygroscopicity in the base material 12 is realized by absorbing water molecules into a large number of minute pores. The substrate 12 absorbs water molecules into the pores when the humidity of the space where the substrate 12 (including the case where the substrate 12 is formed as the inkjet printed product 10) is high. The humidity of the space described above decreases due to the absorption of water molecules. On the other hand, the substrate 12 releases water molecules from the pores when the above-described space is dried and the humidity is lowered. The humidity of the space described above increases due to the release of water molecules. The substrate 12 is formed of a known material having moisture absorption / release properties according to the inkjet printed product 10 which is various products as described above. For example, when the inkjet printed matter 10 is an interior material as described above, the base material 12 is formed of a molded body including inorganic powder in which a large number of minute pores are formed, as shown in Patent Document 3, for example. It is formed.

  The ink dots 14 are formed by, for example, minute ink droplets having a predetermined color landing on the surface of the substrate 12. The ejection of minute ink droplets is performed using the ink jet recording apparatus 20. The outline of the recording method executed by the inkjet recording apparatus 20 will be described later. The pattern expressed on the surface of the substrate 12 by the plurality of ink dots 14 includes a gradation in which the brightness changes continuously (see FIG. 1). A region R1 shown in FIG. 1 is a part of a region where the gradation is formed.

^Gradient, L ^* a * ^{b *} lightness ^{L *} of the maximum value in the color system (hereinafter, "highest lightness ^{L *")} and minimum value (hereinafter, referred to as "minimum lightness ^{L *")} lightness difference [Delta] L ^* is It is set in the range of 8 or more, more preferably in the range of 8-12. The inventor obtained such a range of the brightness difference ΔL ^* through many examinations including the following evaluation results. The L ^* a ^* b ^* color system is a color display method standardized by the International Commission on Illumination (CIE 1976) and defined by JIS (JIS Z 8729: 2004). Therefore, the above-described lightness difference ΔL ^* is specified as a difference between the maximum lightness L ^* and the minimum lightness L ^* based on the L ^* a ^* b ^* color system (maximum lightness L ^* −minimum lightness L ^* ). In the inkjet printed product 10, the lightness L ^* of the surface (background surface) of the substrate 12 is set as the maximum lightness L ^{* in} gradation. Therefore, the gradation is formed with the lightness L ^* of the surface of the substrate 12 as the maximum lightness L ^* . Therefore, the plurality of ink dots 14 are formed in a partial region of the surface of the substrate 12. In other words, the inkjet printed matter 10 is a region in which the surface of the base material 12 is exposed in a finished state in which a pattern is expressed on the surface of the base material 12 and decorated (in FIG. In between ").

  The continuous change in brightness is realized by the density of the plurality of ink dots 14 formed on the surface of the substrate 12 and / or the density of the ink color. For example, the brightness can be reduced by increasing the number of ink dots 14 per unit area and forming the ink dots 14 densely (see FIG. 2). Moreover, the lightness can be reduced by using dark ink as the ink droplets forming the ink dots 14.

<Recording method>
The recording method will be described with reference to FIG. The recording method is a manufacturing method in which a pattern as illustrated in FIG. 1 is expressed on the surface of the substrate 12, and an inkjet printed product 10 decorated with the pattern is manufactured. The recording method is executed by the ink jet recording apparatus 20 as described above. As shown in FIG. 3, the ink jet recording apparatus 20 includes a transport unit 22 and a recording unit 24. The conveyance part 22 is comprised with a conveyor etc., and conveys the base material 12 to a predetermined direction (refer to the "conveyance direction" shown in FIG. 3).

  The recording unit 24 records a pattern on the surface of the substrate 12. The recording unit 24 includes an ink jet head for colors corresponding to the pattern. For example, when yellow, magenta, cyan, and black are used for pattern recording, the recording unit 24 includes ink jet heads for these colors. You may make it use the ink of a color different from these four colors for recording of a pattern. For example, light yellow, light magenta, light cyan and / or clear, which are light colors of yellow, magenta and cyan, may be used. In this case, the recording unit 24 includes a corresponding inkjet head for each color. The color to be used is appropriately determined depending on the design. Each color inkjet head is connected to an ink tank storing ink of each color. The ink of each color is supplied from the ink tank for each color to the corresponding ink jet head.

  For recording the pattern, for example, an active energy curable ink is used. Examples of the active energy curable ink include ultraviolet curable ink and electron beam curable ink. The active energy curable ink contains a pigment, a reactive monomer and / or a reactive oligomer, a photopolymerization initiator, and further contains an additive as necessary.

  When the active energy curable ink is used, the ink jet recording apparatus 20 includes an irradiation unit 26. The irradiation unit 26 is provided on the downstream side of the recording unit 24 in the transport direction. For example, when ultraviolet curable ink is used, the irradiation unit 26 irradiates ultraviolet rays. When the electron beam curable ink is used, the irradiation unit 26 irradiates an electron beam.

  The recording method includes a conveyance process, a recording process, and an irradiation process. The transport process is a process of transporting the base material 12 in the transport direction, and is continuously performed while the recording process and the irradiation process are performed. The base material 12 is placed on the transport unit 22 at a predetermined position on the upstream side in the transport direction, and transported downstream in the transport direction. At that time, the substrate 12 passes through the recording unit 24 and then passes through the irradiation unit 26.

The recording process is a process of recording a pattern on the surface of the substrate 12. When the base material 12 is conveyed to the position of the recording unit 24, ink of each color is ejected toward the surface of the base material 12 from nozzles formed on the ink jet heads for each color. The ejection of ink of each color is controlled according to image data corresponding to the pattern shown in FIG. 1, for example. In the region where the gradation has the maximum brightness L ^* , the ink ejection is not controlled. In other words, the non-ejection of ink is controlled in the region where the gradation has the maximum brightness L ^* . The ejected ink droplets of each color land on the surface of the substrate 12. A plurality of ink dots 14 are formed on the surface of the substrate 12 by the landed ink droplets of each color (see FIG. 2). In FIG. 3, the change in brightness of the gradation included in the pattern is indicated by halftone dots (see “surface of substrate 12”).

  The irradiation step is a step of irradiating the surface of the substrate 12 with active energy rays. When the substrate 12 passes through the recording unit 24 and reaches the irradiation unit 26, active energy rays are irradiated from the irradiation unit 26 to the surface of the substrate 12. For example, when ultraviolet curable ink is used, the irradiation unit 26 irradiates ultraviolet rays. When the electron beam curable ink is used, the irradiation unit 26 irradiates the electron beam. The ink dots 14 on the surface of the substrate 12 are cured with irradiation of active energy rays such as ultraviolet rays or electron beams. In this way, the inkjet printed product 10 is manufactured.

  The ink jet recording apparatus 20 may be either a serial type or a line type. When the active energy curable ink is not used, the ink jet recording apparatus 20 may not include the irradiation unit 26. In the recording method, the irradiation step is omitted. The ink jet recording apparatus 20 is a known recording apparatus, and is widely used when recording a predetermined picture on a predetermined recording medium. Therefore, the other description regarding the recording method is omitted.

<Evaluation of inkjet printed matter>
(1) Lightness difference ΔL ^*
For ink jet printing was measured highest lightness L ^* and lowest lightness L ^* in gradation L ^* a ^* b ^* color system of the pattern expressed on the surface, so called for the lightness difference [Delta] L ^*, which will be described . The pattern expressed on the surface of the sample 1 to be measured was the pattern shown in FIG. The maximum brightness L ^* and the minimum brightness L ^* were measured under the “measurement conditions” described below.

(Measurement condition)
Colorimeter used: CM-700d (Konica Minolta)
Colorimetric mode: SCI (including regular reflection light)
Light source: D65
Viewing angle: 10 degree field of view By the measurement based on the above, the following "Measurement result 1" was obtained. In sample 1, the maximum brightness L ^* is the brightness of the surface of the substrate (beige color).

(Measurement result 1)
Maximum brightness L ^* : 92.06
Minimum brightness L ^* : 81.83
Lightness difference ΔL ^* : 10.23
In addition to sample 1, an ink-jet printed material different from sample 1 was used as sample 2, and the maximum brightness L ^* and the minimum brightness L ^* of the gradation were measured under the above-mentioned “measurement conditions”. The pattern expressed on the surface of the sample 2 to be measured was a pattern (not shown) different from that in FIG. As a result, “Measurement result 2” described below was obtained. The inventors also recognized a suitable three-dimensional effect for the pattern including the gradation expressed on the surface of the sample 2 as in FIG. In sample 2, the maximum lightness L ^* is the lightness of the substrate surface (beige color), as in sample 1.

(Measurement result 2)
Maximum brightness L ^* : 94.30
Minimum brightness L ^* : 85.71
Lightness difference ΔL ^* : 8.59
(2) Hygroscopic and moisture-releasing base material (Eco Carat made by LIXIL Co., Ltd.) on which the design is not expressed, and inkjet printed matter on which the design including the gradation shown in FIG. As samples 3 and 4, the amount of moisture absorption and the moisture release rate were measured, which will be described. Each measurement of moisture absorption and moisture release rate is based on the moisture absorption / release test method for building materials defined in JIS A 1470-1: 2002, and “Procedure 1” to “Procedure” described in “Measurement method” below. 3 ”. Specifically, the amount of moisture absorption was measured in “Procedure 1” and “Procedure 2”, and the moisture release rate was measured in “Procedure 1” to “Procedure 3”. Since sample 3 (base material) and sample 4 (ink-jet printed matter) were measured only on the surface, the side and back surfaces were covered with aluminum tape.

(Measuring method)
Procedure 1: Curing the substrate and inkjet printed material for 48 hours in an environment at a temperature of 23 ° C. and a humidity of 50% Procedure 2: After the procedure 1, the substrate and inkjet printed material are placed in an environment of a temperature of 23 ° C. and a humidity of 75% Place 3 hours, 6 hours, and 12 hours to measure the amount of moisture absorbed. Step 3: After step 2, place the substrate and inkjet prints in an environment of 23 ° C and 50% humidity for 12 hours. Measure the moisture release rate after 12 hours (measurement result)
The result shown in FIG. 4 was obtained by the measurement based on the above. Both the amount of moisture absorption and the moisture release rate were the same in Samples 3 and 4. That is, it was confirmed that the same hygroscopic property and moisture releasing property as those of the base material can be obtained with the ink jet printed matter of the present embodiment. In addition, the inventor has made a great deal of study on the hygroscopicity so that the difference in the moisture absorption amount between the substrate and the inkjet printed material (the moisture absorption amount of the substrate−the moisture absorption amount of the inkjet printed material) is 4 g / m ² or less. It is suitable for the moisture-absorbing / releasing properties of the ink-jet printed matter to ensure moisture-releasing properties such that the difference between the moisture-releasing rate of the ink-jet printed matter (moisture-releasing rate of the substrate-moisture-releasing rate of the ink-jet printed matter) is 5% or less It is important to realize

<Effect of this embodiment>
According to this embodiment, the following effects can be obtained.

(1) L ^* a ^* b ^* A pattern including a gradation in which the lightness difference ΔL ^* between the maximum value and the minimum value of the lightness L ^* in the color system is set in the range of 8 to 12 is expressed on the surface of the base 12 Inkjet print 10 was obtained. Therefore, a pattern having a suitable three-dimensional effect can be expressed on the surface of the inkjet printed matter 10.

  In addition, the pattern is formed by a plurality of ink dots 14 formed in a partial region of the surface of the substrate 12. Therefore, it becomes possible to ensure the area | region where the ground surface of the base material 12 has exposed on the surface of the inkjet printed matter 10, and it can maintain moisture absorption / release property.

(2) The gradation was made into the structure which made the lightness L ^* in the L ^* a ^* b ^* color system of the surface of the base material 12 the maximum lightness L ^* . Therefore, a gradation can be formed using the ground surface of the base material 12, and the pattern which has a three-dimensional effect can be expressed. Moisture absorption and desorption can be maintained in a region where the maximum brightness L ^* is obtained in gradation.

<Modification>
This embodiment can also be performed as follows.

  (1) In the above, the pattern and the gradation which decorate the surface of the inkjet printed matter 10 were demonstrated to the example shown in FIG. The design and gradation may be a different design. Which design is selected is appropriately determined based on the demands of designers and / or consumers.

(2) According to this embodiment mentioned above, the following building interior materials can also be specified. A base material and a plurality of ink dots that form a pattern expressed on the surface of the base material and are formed in a partial region of the surface of the base material. The pattern expressed on the surface of the material includes a gradation in which the brightness changes continuously, and the gradation is a brightness difference ΔL ^* between the maximum value and the minimum value of the brightness L ^* in the L ^* a ^* b ^* color system ^. Can be specified as an inkjet print product in which is set in the range of 8-12.

  A plurality of ink dots that form a pattern expressed on the surface of the base material and have a plurality of ink dots formed in a partial region of the surface of the base material. The pattern expressed on the surface of the base material by the ink dots can also specify an inkjet printed matter including a gradation whose brightness changes continuously.

In these ink-jet printed matter, the gradation is formed a lightness L ^* in the L ^* a ^* b ^* color system of the surface of the substrate as the highest lightness L ^*, may be.

DESCRIPTION OF SYMBOLS 10 Inkjet printed matter 12 Base material 14 Ink dot 20 Inkjet recording apparatus 22 Conveyance part 24 Recording part 26 Irradiation part R1 area | region

Claims (2)

A moisture-absorbing and releasing ink-jet print with a pattern on the surface,
A substrate having a moisture absorption / release property whose outer shape is rectangular;
Forming a pattern represented on the surface of the substrate, and a plurality of ink dots formed in a partial region of the surface of the substrate;
The pattern expressed on the surface of the base material by the plurality of ink dots increases the number of the ink dots per unit area as the brightness decreases, so that the predetermined two sides of the base material facing each other are increased. the brightness in a specific direction along the continuously changed to Heidelberg Gradient includes a plurality in the specific direction,
In the gradation, the lightness difference ΔL ^* between the maximum value and the minimum value of the lightness L ^* in the L ^* a ^* b ^* color system is set in the range of 8 to 12, and L ^* a ^{* on} the surface of the base material ^. b ^* lightness ^{L *} in the color system is a lightness ^{L *} of the maximum value,
In the pattern expressed on the surface of the base material by the plurality of ink dots, the region of the highest value L ^* of the first gradation of the plurality of gradations and the second gradation of the plurality of gradations And an area of the lowest lightness L ^* of the inkjet printed matter arranged continuously in the specific direction. The inkjet printed matter is a building interior material or wallpaper,
The plurality of ink dots are the base material in a state where Procedure 1 and Procedure 2 of the following measurement method are performed in accordance with a moisture absorption / release test method for building materials defined in JIS A 1470-1: 2002, and In the inkjet print, the difference in moisture absorption by subtracting the moisture absorption on the surface of the substrate from the moisture absorption on the surface of the substrate is 2.5 g / m ² or less, and conforms to the moisture absorption / release test method. In the base material and the inkjet printed product in the state where the procedure 1, procedure 2 and procedure 3 of the following measurement method are performed, the moisture release rate of the surface of the inkjet printed product is determined from the moisture release rate of the surface of the substrate. The inkjet printed matter according to claim 1, wherein the printed matter is formed on the surface of the base material in a state where a difference of the subtracted moisture release rate is 4.8% or less.
(Measuring method)
Procedure 1 : Curing the substrate and inkjet printed material for 48 hours in an environment at a temperature of 23 ° C. and a humidity of 50% Procedure 2: After the procedure 1, the substrate and inkjet printed material are placed in an environment of a temperature of 23 ° C. and a humidity of 75% Place for 12 hours Step 3: After step 2, place the substrate and inkjet prints in an environment of temperature 23 ° C. and humidity 50% for 12 hours