KR20240169439A - The ink-jet recording material and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a material for an inkjet printer, which uses a Tyvek substrate with low wrinkling and tearing properties, has excellent adhesion to a printed matter by inkjet printing, and excellent water resistance and solvent resistance of the printed matter, and a method for manufacturing the same.

Description

{The ink-jet recording material and manufacturing method thereof}

The present invention relates to a material for an inkjet printer, which uses a Tyvek substrate with low wrinkling and tearing properties, has excellent adhesion to a printed matter by inkjet printing, and excellent water resistance and solvent resistance of the printed matter, and a method for manufacturing the same.

Tyvek is a high-density polyethylene fabric developed by DuPont. It is lightweight, strong, flame-retardant, breathable, and highly durable against water, wear, and bacteria, and is used in a variety of industries. Specifically, Tyvek has excellent heat retention and insulation properties, so it is used as interior and exterior materials for buildings, and it is used to make personal protective equipment for workers in special environments who are exposed to radiation and hazardous substances, because it has excellent chemical resistance. There are also attempts to use it as an industrial cargo cover or special packaging material, or as a fashion item.

With the advancement of digital printing equipment, the use of inkjet printers is spreading. Inkjet printing is widely used for general household, commercial, and industrial purposes due to its advantages of fast printing speed, low printer price, and recently, high-resolution images.

The output paper for general inkjet printers is often made of paper substrates such as photo paper, and depending on the intended use (commercial or household), synthetic resin film is also used.

These inkjet printer papers and synthetic resin films are provided with an ink-receiving layer coated on the surface of the paper or synthetic resin film substrate that has the property of sufficiently absorbing water-based or oil-based ink while producing a clear image. However, in the case of paper or synthetic resin films, there is a disadvantage in that wrinkles or tears easily occur after printing, and inkjet output images can be erased by water or solvents.

Registered Patent No. 10-2502095

Accordingly, the inventors of the present invention have sought to develop a material for an inkjet printer that can be used not only for simple printed matter with a desired image but also for fashion items such as clothing and bags, by using a substrate with excellent folding resistance that is less prone to wrinkling or tearing and causes less damage to the coating layer when folded.

Accordingly, the inventors of the present invention selected Tyvek fiber as a substrate with low wrinkling and tearing properties and excellent folding resistance, and sought to develop a material for an inkjet printer that can be used for fashion items such as clothing and bags.

However, in the case of Tyvek fiber, the surface is not flat, and the thickness can vary by up to 50 to 100㎛ even in the same product, making it difficult to obtain a uniform ink-absorbing layer. In addition, the adhesion between the Tyvek fiber base layer and the ink-absorbing layer is not good, resulting in a lifting phenomenon between the two layers. It was not easy to obtain high-quality prints using the conventional inkjet method.

Accordingly, the purpose of the present invention is to provide a material for an inkjet printer having excellent wrinkling and tearing properties and excellent folding resistance, so as to enable the production of various products by inkjet printing not only for industrial purposes but also for daily life, by treating Tyvek fibers and providing the material for an inkjet printer.

It is also an object of the present invention to provide a method for manufacturing a material for an inkjet printer by treating Tyvek fibers.

In order to achieve the first aspect of the present invention, the present invention provides a material for an inkjet printer including a substrate layer, a primer layer, and an inkjet absorbing layer (top layer).

(1) The above-mentioned substrate layer is made of Tyvek fiber,

(2) The primer layer comprises an oil-based urethane binder and pigment,

(3) The ink-absorbing layer provides a material for an inkjet printer, characterized in that it includes pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent.

In order to achieve the second aspect of the present invention, the present invention

(a) a step of preparing Tyvek fiber as a substrate;

(b) a step of preparing a coating solution for a primer layer containing a polyurethane binder, pigment and solvent;

(c) a step of preparing a coating solution for an ink-absorbing layer comprising water, pigment, first PVA, second PVA, cross-linking agent, ink fixing agent, and leveling agent;

(d) a step of coating a coating solution for a primer layer on the above-mentioned substrate and drying it to create a primer layer; and

(e) A method for manufacturing a material for an inkjet printer is provided, including the step of coating a coating solution for an ink-absorbing layer on the primer layer and drying it to manufacture an ink-absorbing layer.

Unlike conventional inkjet films, the material for an inkjet printer of the present invention has excellent wrinkle and tear properties and excellent folding resistance, so that it is possible to produce printed products that can be used for various purposes through inkjet printing.

The material for an inkjet printer of the present invention can obtain high-quality images through inkjet printing, and has excellent water resistance and solvent resistance of the produced printed matter, so that the durability of manufacturing sites and photographs and printed outputs is excellent.

The inkjet printer material of the present invention can be used in everyday life and industrial applications by means of inkjet printing, and can also be used for clothing, bags, etc. The inkjet printer material of the present invention has the effect of obtaining printed matter that can be utilized in various fields by simply printing it by means of inkjet printing.

FIG. 1 is a cross-sectional view of a material for an inkjet printer according to one embodiment of the present invention.

Hereinafter, the present invention will be described in detail. The purpose, specific advantages, and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments in conjunction with the accompanying drawings, but the present invention is not necessarily limited thereto. In addition, in describing the present invention, if it is judged that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

The present invention relates to a material for an inkjet printer comprising a substrate layer, a primer layer, and an inkjet absorbing layer (top coat layer).

(1) The above-mentioned material layer is made of Tyvek material.

(2) The primer layer contains pigment and oil-based urethane binder,

(3) The ink-absorbing layer provides a material for an inkjet printer, characterized in that it includes pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent.

Fig. 1 is a cross-sectional view of a material (10) for an inkjet printer according to one embodiment of the present invention. As shown in Fig. 1, the material for an inkjet printer of the present invention includes a substrate layer (1), a primer layer (2) formed on the substrate layer (1), and an ink-absorbing layer (top layer) (3) formed on the primer layer (2).

The inventors of the present invention have recognized that, in the case of conventional synthetic resin films or papers for inkjet printers, the substrates are wrinkled or torn and foldable, making it difficult to utilize them for various purposes when producing printed matter using them. In addition, since there is a phenomenon in which the printed matter obtained by inkjet printing on the synthetic resin films or paper is erased by water or organic solvents, or the ink-absorbing layer (top layer) is detached from the substrate, the inventors have attempted to find a method to improve this phenomenon.

The inventors of the present invention attempted to obtain a printed material using an inkjet method using Tyvek fibers as a substrate, which have the breathability of paper, the wrinkability of fabric, and the durability of film. However, in the case of Tyvek fibers, the surface is not flat, and even in the same product, the thickness differs by up to 50 to 100 ㎛, making it difficult to obtain a uniform ink-absorbing layer, and there was a problem that the adhesion between the Tyvek fiber substrate and the ink-absorbing layer was not good, resulting in a lifting phenomenon between the two layers.

Accordingly, the inventors of the present invention have developed a material for an aqueous or oil-based inkjet printer having an ink-absorbing layer for inkjet printing on a Tyvek substrate, wherein the material has a primer layer between the Tyvek substrate and the ink-absorbing layer for inkjet printing. The material for an inkjet printer has excellent adhesion to printouts produced by an inkjet printer, and the ink-absorbing layer has excellent resistance to water and solvents.

In addition, in the case of the inkjet printer material of the present invention, there is no problem such as cracks or pinholes on the surface of the inkjet printer material, and further, the level of the coating liquid for the coating layer of the substrate, primer layer, and ink-absorbing layer is excellent, so there is an advantage of not causing non-coating (a state in which coating is not performed).

Hereinafter, the material for the inkjet printer of the present invention will be described in detail.

(1) Description

The present invention includes Tyvek manufactured by a special process rather than paper or synthetic resin film having a relatively flat surface and uniform thickness, which are generally used as a substrate for materials for inkjet printers.

Tyvek is a high-density polyethylene fiber that has the breathability of paper, the wrinkability of fabric, and the durability of synthetic resin film.

Tyvek used as a substrate of the present invention is of a hard type similar to paper and a soft type similar to fiber, but is not limited to the type.

In other words, if you use a hard type Tyvek similar to paper, you can produce excellent printed materials that feel like paper but are soft and durable. Because it can have the same feel as existing paper while also being waterproof and highly durable, it can be used for various printed materials.

If you use a soft type of Tyvek similar to cloth, it can provide a cloth-like texture and softer feel, and can be used to manufacture clothing, bags, etc. through sewing.

The above Tyvek substrate may preferably have an average thickness of 150-300㎛, more preferably 175-275㎛, for printing with an inkjet printer. The weight per unit area may be 50-110g/ ^m2 . When the thickness of the Tyvek substrate is as above or the weight per unit area is as above, various printed materials can be produced by inkjet printing.

(2) Primer layer

The Tyvek used as a substrate does not have a flat surface, and even in the same product, the thickness can differ by up to 50 to 100 μm, making it difficult to perform a uniform coating with a general coating agent. In addition, there is a phenomenon in which the ink-absorbing layer (top layer) is detached. Accordingly, in the present invention, efforts were made to form a uniform primer layer while maintaining the adhesion between the Tyvek substrate and the ink-absorbing layer, and the primer layer of the present invention was developed, and a coating solution for an ink-absorbing layer (top layer) having leveling properties matching that of the primer coating was coated thereon, thereby finally completing a material for an inkjet printer.

The primer layer of the present invention resolves the unevenness of the Tyvek substrate layer and improves the adhesion between the substrate layer and the ink-absorbing layer.

The primer layer (2) of the present invention includes an oil-based urethane binder and pigment as a binder resin.

The polyurethane binder of the present invention has good compatibility with both the substrate and the ink-absorbing layer, thereby making the surface tension similar, so that there are no problems such as cracks or pinholes on the surface of the material for an inkjet printer, and also has the advantage of excellent leveling of the substrate and the ink-absorbing layer, so that no coating occurs.

The oil-based urethane binder of the present invention is a urethane binder capable of forming a cross-linking or network structure by having an ester group of the following chemical formula 1 bonded to a urethane polymer main chain, and can improve the adhesive strength between the base layer and the ink-absorbing layer by forming a condensation polymerization, covalent bond, or hydrogen bond between the main chains and the Tyvek base material. The oil-based urethane binder is a binder having a weight average molecular weight of 30,000-100,000, preferably 50,000-80,000.

[Chemical Formula 1]

-R1-C(=O)-O-R2

In the above chemical formula 1,

R1 is a C1-C10 alkylene group which may be substituted with one or more substituents selected from a carboxyl group, a carbonyl group, an OH group, and an ester group as a bond or functional group,

R2 is a C1-C10 alkyl group which may be substituted with one or more substituents selected from a carboxyl group, a carbonyl group, an OH group, and an ester group.

Preferably, R1 and/or R2 have two or more functional groups. In this case, the adhesion between the substrate layer and the ink-absorbing layer can be further improved by forming a condensation polymerization, covalent bond, or hydrogen bond between the main chain and the Tyvek substrate.

The pigment is preferably solid silica, silica sol, alumina sol or calcium carbonate. The average particle size of the pigment of the primer layer is 1 to 5 μm, preferably 2 to 3 μm. When the particle size of the pigment is as described above, the primer layer can further improve the adhesion between the substrate layer and the ink-absorbing layer.

The above-mentioned oil-based urethane binder and pigment may preferably include 90 to 99.9 wt% of the oil-based urethane binder and 0.1 to 10 wt% of the pigment based on the total weight of the primer layer, more preferably 95 to 99.5 wt% of the oil-based urethane binder and 0.5 to 5 wt% of the pigment, and in this case, the base layer and the ink-absorbing layer may have appropriate adhesive strength.

The thickness of the above primer layer is 2 to 10 μm, preferably 3 to 7 μm, and more preferably 3 to 5 μm. When the thickness of the primer layer is as described above, adhesion can be provided without making the thickness of the material for an inkjet printer excessively high.

(3) Inkjet absorbing layer (top coat)

The ink-absorbing layer (top layer) of the present invention is a layer that absorbs water-based or oil-based ink, and absorbs the ink of a print output printed by a high-speed inkjet printer using dye and pigment inks to create a clear image, while also providing water resistance and solvent resistance so that the image is not erased by water or solvents.

The material for an inkjet printer of the present invention has excellent water resistance by including the ink-absorbing layer of the present invention, and also has excellent solvent resistance to organic solvents such as methyl ethyl ketone (MEK), isopropyl alcohol (IPA), ethanol, methanol, acetone, etc., so that it has the advantage of being able to preserve records and shapes without deformation for a long period of time.

That is, the ink-absorbing layer (top layer) of the present invention is a layer that receives ink and leaves a desired record, and it is preferable that it has excellent moisture absorption and ink fixation properties for ink, and excellent water resistance and solvent resistance.

The ink-absorbing layer (top layer) of the present invention includes a pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent.

The pigment of the above ink-absorbing layer plays a role in absorbing the ink being printed, and solid silica, silky sol or alumina sol is preferable. The average particle size of the pigment of the above ink-absorbing layer is 5 to 11 ㎛, preferably 7 to 10 ㎛. When the particle size of the pigment is as above, the hygroscopicity and ink fixation property for ink are excellent.

The pigment may be present in an amount of 5 to 20 wt%, preferably 7 to 15 wt%, and more preferably 8 to 13 wt%, relative to the total weight of the ink-absorbing layer. In this case, ink spreading may be reduced, and high absorbency and high color development of the ink-absorbing layer may be enhanced.

The above ink-absorbing layer includes a first PVA binder and a second PVA binder as binders.

The first PVA binder is a polyvinyl alcohol having, as a functional group, at least one functional group selected from the group consisting of a carboxyl group, an ammonium group, a sulfonium group, and a silanol group, as a modified polyvinyl alcohol system, and the first PVA binder has a weight average molecular weight of 500 to 1,000. The second PVA binder is a polyvinyl alcohol having, as a functional group, at least one functional group selected from the group consisting of a carboxyl group, an ammonium group, a sulfonium group, and a silanol group, as a modified polyvinyl alcohol system, and the second PVA binder has a weight average molecular weight of 900 to 1,500. Preferably, the functional group of the first PVA binder is different from the functional group of the second PVA binder.

The ink-absorbing layer of the present invention has the advantage of improving the dispersibility of pigments without a separate dispersing agent by including a first PVA binder and a second PVA binder having different functional groups as binders, and improving the adhesion of the absorbing layer and the absorption and binding force of water-based ink. To this end, the first PVA binder and the second PVA binder of the ink-absorbing layer of the present invention may include 80 to 95 wt% of the first PVA binder and 5 to 20 wt% of the second PVA binder based on the total weight of the binders.

The binder is contained in an amount of 60 to 90 wt%, preferably 70 to 85 wt%, relative to the total weight of the ink-absorbing layer, thereby facilitating adhesion of the ink-absorbing layer without interfering with absorption of ink.

The ink-absorbing layer of the present invention includes a cross-linking agent. The cross-linking agent is characterized in that it includes at least one selected from the group consisting of an adipic acid/epoxypropyl diethyleneamine copolymer, a dimethylamine/epichlorohydrin copolymer, a dimethylamine/epichlorohydrin/ethylenediamine copolymer, glyoxal, a urea/polymer with ethanedial, and an ethyleneepoxyamine/adipic acid/urea condensate, and is characterized in that it provides water resistance and solvent resistance by cross-linking a functional group of modified PVA. For this purpose, it may be included in an amount of 3 to 12 wt%, preferably 5 to 10 wt%, based on the total weight of the ink-absorbing layer.

The ink-absorbing layer (top layer) (3) of the present invention contains an ink fixing agent together with a pigment. The ink fixing agent preferably contains at least one selected from the group consisting of a dimethylamine/epichlorohydrin copolymer, a dimethylamine/epichlorohydrin/ethylenediamine copolymer, a diallyldimethyl ammonium chloride polymer, an acryloyloxyethyltrimethyl ammonium chloride polymer, an ethylenediamine polymer, and a dimethylamine polymer. The ink fixing agent of the present invention serves to hold ink pigments or dyes, thereby allowing them to be well fixed on the surface of the print-absorbing layer. In addition, it helps prevent characters or shapes printed on the inkjet printer material of the present invention from being easily erased by water or an organic solvent. To this end, the ink fixing agent may be contained in an amount of 0.5 to 7 wt%, preferably 1 to 5 wt%, relative to the total weight of the ink-absorbing layer (top layer).

The ink-absorbing layer of the present invention includes a leveling agent. The leveling agent of the present invention is preferably an alcohol-based ethoxylate. The ink-absorbing layer of the present invention may include 0.1 to 1 wt% of the leveling agent based on the total weight of the ink-absorbing layer. By including the leveling agent in the above amount, there is an advantage of matching the leveling properties with the primer layer.

The ink-absorbing layer of the present invention contains pigment, a binder, a cross-linking agent, an ink fixing agent, and a leveling agent in an amount of 5 to 20 wt% of pigment, 60 to 90 wt% of binder, 3 to 12 wt% of cross-linking agent, 0.5 to 7 wt% of ink fixing agent, and 0.1 to 1 wt% of leveling agent based on the total weight of the ink-absorbing layer, and thus binds well to a primer layer coated on a Tyvek substrate, and at a relatively low cost, it holds ink pigment or dye well, allowing the pigment or dye to settle well on the surface of the ink-absorbing layer, thereby exhibiting high absorbency and high color development, and also exhibiting resistance to water or solvents.

The ink-absorbing layer (top layer) of the present invention preferably has a thickness of 20-40 ㎛ to capture ink pigments or dyes.

The ink-absorbing layer (top layer) of the present invention may further include additives to improve physical properties.

The above additives may include thickeners, pH regulators, antioxidants, anti-foaming agents, surfactants, etc.

A second aspect of the present invention is to provide a method for manufacturing a material for an inkjet printer of the first aspect.

Below, a method for manufacturing a material for an inkjet printer of the present invention is described.

A method for manufacturing a material for an inkjet printer of the present invention

(a) Step for preparing Tyvek substrate;

(b) a step of preparing a coating solution for a primer layer containing a polyurethane binder, pigment and solvent;

(c) a step of preparing a coating solution for an ink-absorbing layer comprising water, pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent.

(d) a step of manufacturing a primer layer by coating a coating solution for a primer layer on the above-mentioned substrate and drying it; and

(e) Provided is a method for manufacturing a material for an inkjet printer, including the step of coating a coating solution for an ink-absorbing layer on the primer layer and drying it to manufacture an ink-absorbing layer.

(a) Preparation of the description

As described above in the first aspect of the present invention, the substrate layer (1) is made of Tyvek material.

(b) Preparation of coating solution for primer layer

In order to manufacture the primer layer of the present invention, a coating solution is prepared by dissolving and dispersing the oil-based urethane binder and pigment from the first aspect in a solvent.

The solvent is not limited to the type of organic solvent, but is preferably at least one selected from the group consisting of methyl ethyl ketone (MEK), acetone, ethyl acetate (EA), isopropyl alcohol (IPA), and toluene (TOL), and more preferably methyl ethyl ketone (MEK) and/or isopropyl alcohol (IPA).

The coating solution for manufacturing the above primer layer may contain 20 to 50 wt% of a solvent, 50 to 80 wt% of a pigment and an oil-based urethane binder. Since the coating solution contains the solvent in the above amount, the primer layer can be uniformly coated on the Tyvek substrate.

(c) Preparation of coating solution for ink absorption layer (top layer)

The coating solution for the ink-absorbing layer (top layer) of the present invention is prepared by dissolving and dispersing the pigment from the first perspective, the first PVA binder, the second PVA binder, the cross-linking agent, the ink fixing agent, and the leveling agent in water. The coating solution for preparing the ink-absorbing layer uses water as a solvent, so it is excellent in environmental issues and workability.

A coating solution for the ink-absorbing layer of the present invention is prepared, which contains 20 to 50 wt% of water and 50 to 80 wt% of pigment, binder, cross-linking agent, ink fixing agent, and leveling agent.

(d) Manufacturing of primer layer

A primer layer is created by coating a coating solution for a primer layer on a substrate and drying it.

The method of coating the coating solution for the primer layer is not particularly limited, and can be used selectively depending on the properties of the coating solution for the primer layer.

For example, wire bar coating, microgravure coating, and slot die coating methods can be used. According to one specific example of the present invention, the thickness of the primer layer applied on the substrate during the coating is 2 to 10 ㎛, preferably 3 to 7 ㎛, and more preferably 3 to 5 ㎛. If the primer layer is less than 1 ㎛, it does not sufficiently perform its function, and if it is more than 10 ㎛, it does not show any change in adhesion, so there is no need to form it thicker.

The above thickness refers to the thickness of the solid content after coating and drying.

(e) Manufacturing of ink-absorbing layer (top layer)

An ink-absorbing layer is manufactured on the primer layer using the ink-absorbing layer coating solution described above.

The coating method may be, for example, wire bar coating, microgravure coating, and slot die coating. According to one specific example of the present invention, the thickness of the ink-absorbing layer (top layer) applied on the substrate during the coating is 20 to 40 μm in consideration of ink absorbency and fixation. If the thickness is less than the above, it is difficult to hold the pigment or dye of the ink, and if it is greater than the above thickness, there is no change in ink absorbency and fixation, so there is no need to form it thicker.

Hereinafter, preferred embodiments are presented to help understand the present invention; however, the following embodiments are provided only to make the present disclosure easier to understand, and the present invention is not limited thereto.

Example

Performance Evaluation Criteria

The performance of the examples and comparative examples was evaluated based on the following performance evaluation criteria.

1. Water resistance

After printing an image on inkjet printer material using an inkjet printer (EPSON L805), water was dropped on the printed surface, and after 1 minute, the rubbing was visually checked and converted into an achievement rate of the internal management water resistance standard to evaluate the water resistance standard.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Bad (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

2. Content-based (MEK)

After printing an image on inkjet printer material using an inkjet printer (EPSON L805), a solvent (MEK) was dropped on the printed surface, and the rubbing was immediately checked with the naked eye and converted into an achievement rate of the internal management content resistance standard to evaluate the content resistance standard.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Defective (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

3. Contents (IPA)

After printing an image on a water-based inkjet printer film using an inkjet printer (EPSON L805), a solvent (IPA) was dropped on the output surface, and immediately rubbing was visually checked and the content resistance standard was evaluated by converting it into the achievement rate of the internal management content resistance standard value.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Bad (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

4. Contents (Ethanol)

After printing an image on a water-based inkjet printer film using an inkjet printer (EPSON L805), a solvent (ethanol) was dropped on the printed surface, and the rubbing was immediately checked with the naked eye. The content resistance standard was evaluated by converting it into the achievement rate of the internal management content resistance standard value.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Bad (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

5. Contents (Acetone)

After printing an image on a water-based inkjet printer film using an inkjet printer (EPSON L805), a solvent (Acetone) was dropped on the printed surface, and the rubbing was immediately checked with the naked eye. The content resistance standard was evaluated by converting it into the achievement rate of the internal management content resistance standard value.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Bad (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

6. Ink Absorption

After printing an image on inkjet printer material using an inkjet printer (EPSON L805), the resolution of the printed image was visually checked and the ink absorbency standard was evaluated by converting it into an achievement rate of the internal management ink absorbency standard value.

○: Good (100% output image preservation)

△: Somewhat inadequate (80-99% output image retention)

× : Bad (output image retention 50-79%)

××: Extremely poor (output image preservation less than 50%)

7. Adhesiveness

After printing an image on inkjet printer material using an inkjet printer (EPSON L805), a tape (3M) was attached to the printed image, and then removed by going back and forth three times with a 1.3 kg roller, and the adhesion standard was evaluated by converting it into the achievement rate of the internal management adhesion standard value.

○: Good (Coating layer/image preservation 90-100%)

△: Somewhat inadequate (coating layer/image preservation 70-90%)

× : Defective (Coating layer/Image preservation 50-69%)

××: Extremely poor (Coating layer/image preservation less than 50%)

8. Coating surface

When coating the primer layer and ink-absorbing layer on materials for inkjet printers, the occurrence of pinholes and non-coating was measured visually at 1 m in width and length. The degree of coating surface defects was evaluated by comparing them with the preset internal management standard range.

○ : Good (0)

△ : Somewhat insufficient (1-2)

× : Defective (3-10)

××: Extremely bad (10 or more)

Example 1

Preparation of the article

Tyvek fiber with a thickness of 210㎛ was prepared as a substrate.

Preparation of coating solution for primer layer

A solvent (39.5 wt% of methyl ethyl ketone (MEK) and ethyl acetate (EA) in a 1:1 weight ratio) and a pigment (Silica) (0.5 wt%) were added, dispersed sufficiently with a dissolver, and 60 wt% of an oil-based urethane binder was added and stirred with a dissolver to prepare the solution.

Preparation of coating solution for ink-absorbing layer

35.8 wt% of water, 6 wt% of pigment (Silica), 47 wt% of modified polyvinyl alcohol containing a carboxyl group as a first PVA binder, 4 wt% of modified polyvinyl alcohol containing a silanol group as a second PVA binder, 5 wt% of dimethylamine/epichlorohydrin copolymer as a crosslinking agent, 2 wt% of dimethylamine/epichlorohydrin/ethylenediamine copolymer as an ink fixing agent, and 0.2 wt% of alcohol ethoxylate as a leveling agent were added and stirred with a dissolver to prepare.

Primer layer formation

The primer layer was formed by coating and drying the coating solution for the primer layer on a Tyvek fiber substrate having a thickness of 210 μm using a wire bar coating method so that the primer layer had a thickness of 3 to 4 μm.

Formation of ink-absorbing layer (top layer)

The ink-absorbing layer was formed by coating and drying the coating solution for the ink-absorbing layer (top layer) using a slot die coating method on the primer layer so that the thickness of the ink-absorbing layer was 30 ㎛.

As a result of performance evaluation of the material for an inkjet printer manufactured according to Example 1, it was evaluated that the water resistance, solvent resistance, coating surface property, and adhesion were satisfactory, and ink absorbency was also good.

Example 2

Preparation of the article

Tyvek fiber with a thickness of 210㎛ was prepared as a substrate.

Preparation of coating solution for primer layer

A coating solution for the primer layer was prepared in the same manner as in Example 1 with the contents shown in Table 1 below.

Preparation of coating solution for ink-absorbing layer

A coating solution for an ink-absorbing layer was prepared in the same manner as in Example 1 with the contents shown in Table 1 below.

Primer layer formation

The primer layer coating solution was coated and dried on a Tyvek oil base having a thickness of 210 μm using a wire bar coating method so that the primer layer had a thickness of 3 to 4 μm.

Formation of ink-absorbing layer (top layer)

The coating solution for the ink-absorbing layer (top layer) was coated and dried on the primer layer using a slot die coating method so that the thickness of the ink-absorbing layer became 30 ㎛.

As a result of performance evaluation of the material for an inkjet printer manufactured according to Example 2, it was evaluated that the water resistance, solvent resistance, coating surface property, and adhesion were satisfactory, and ink absorbency was also good.

Comparative Example 1

Preparation of the article

A substrate of Tyvek fiber with a thickness of 210㎛ was prepared.

Preparation of coating solution for primer layer

After adding 27 wt% of water and 3 wt% of pigment (silica), the mixture was sufficiently dispersed with a dissolver, and 70 wt% of a water-based acrylic binder was added and stirred with a dissolver to prepare the mixture.

Preparation of coating solution for ink-absorbing layer

10 wt% of water, 7 wt% of pigment (silica), 74 wt% of the first PVA binder, 4 wt% of a crosslinking agent, 2 wt% of a dispersant, and 3 wt% of an ink fixing agent were added and stirred with a dissolver to prepare the mixture.

Primer layer formation

The coating solution for the primer layer was coated and dried on a Tyvek fiber substrate having a thickness of 210 μm using a wire bar coating method so that the thickness of the primer layer was 3 to 4 μm.

Formation of ink-absorbing layer (top layer)

The coating solution for the ink-absorbing layer (top layer) was coated and dried on the primer layer using a slot die coating method so that the thickness of the ink-absorbing layer became 30 ㎛.

Comparative examples 2 to 6

Materials for inkjet printers of Comparative Examples 2 and 3 were manufactured using the contents in Table 1 below, and materials for printers of Comparative Examples 4 to 6 were manufactured using MEK and EA in a weight ratio of 1:1 as a solvent and the contents in Table 1 below, and were evaluated in the same manner as Comparative Example 1.

As a result of performance evaluation of materials for inkjet printers of Comparative Examples 1 to 3, which manufactured primer layers using water and water-based acrylic binders, the water resistance for inkjet-printed images was 50-79%, the solvent resistance was 50-79%, and the adhesion was 50-79%, and in particular, the adhesion was evaluated as poor.

In Comparative Examples 4 and 5, where an organic solvent was used in the manufacture of the primer layer and an oil-based acrylic binder was used as the binder, the water resistance was excellent, but the solvent resistance was somewhat inadequate, and the adhesion and coating surface properties were poor. In Comparative Example 6, where an organic solvent was used in the manufacture of the primer layer and an oil-based urethane binder was used as the binder, but the second PVA was not used in the ink-absorbing layer, the adhesion and coating surface properties were excellent, but the water resistance and solvent resistance were somewhat inadequate.

The performance evaluation results of the aforementioned Examples 1 and 2 and Comparative Examples 1 to 6 are shown in Table 1 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Primer layer water 27 27 20 solvent 39.5 38 25 27 28.5 Pigment 0.5 1.5 3 3 3 3 3 1.5 Mercury Acrylic Binder 70 70 77 Acrylic binder with oil 72 70 Polyurethane binder 60 60 70 Ink absorbing layer water 36 34 10 26 6 10 26 6 Pigment 6 7 7 5 7 7 5 7 1st PVA 47 47 74 62 78 74 62 78 2nd PVA 4 5 Crosslinking agent 5 5 4 2 4 4 2 4 Dispersant 2 2 2 2 2 2 Ink fixative 2 2 3 2 2 3 2 2 Leveling agent 0.2 0.2 1 1 1 1 Thickness (㎛) Primer layer 3~4 3~4 3~4 3~4 2~3 3~4 3~4 3~4 Ink absorbing layer 30 30 30 30 25 30 30 30 Physical properties Water resistance ○ ○ X X X ○ ○ △ Content-based (MEK) ○ ○ X X X △ △ △ Content-based (IPA) ○ ○ X X X △ △ △ Content (ethanol) ○ ○ X X X △ △ ○ Contents (acetone) ○ ○ X X X ○ ○ ○ Ink absorbency ○ ○ X X X ○ X △ Adhesion ○ ○ X X X △ △ ○ Coating surface ○ ○ X X X △ △ ○

Content is weight %

10: Materials for inkjet printers
1: Base layer
2: Primer layer
3: Ink absorption layer (top layer)

Claims (11)

A material for an inkjet printer including a substrate layer, a primer layer, and an ink-absorbing layer.
The above-mentioned substrate layer is made of Tyvek fiber,
The above primer layer comprises an oil-based urethane binder and pigment,
The above ink-absorbing layer is a material for an inkjet printer including pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent. In claim 1,
A material for an inkjet printer, characterized in that the thickness of the substrate layer is 150-300㎛ on average, the thickness of the primer layer is 2-10㎛, and the thickness of the ink-absorbing layer is 20-40㎛. In claim 1,
A material for an inkjet printer, characterized in that the primer layer contains 90 to 99.9 wt% of an oil-based urethane binder and 0.1 to 10 wt% of a pigment based on the total weight of the primer layer. In claim 1,
The ink-absorbing layer is a material for an inkjet printer, comprising 5 to 20 wt% of pigment, 60 to 90 wt% of binder, 3 to 12 wt% of cross-linking agent, 0.5 to 7 wt% of ink fixing agent, and 0.1 to 1 wt% of leveling agent based on the total weight of the ink-absorbing layer. In claim 1,
The above-mentioned oil-based urethane binder is a material for an inkjet printer, characterized in that it is a urethane binder in which an ester group of the following chemical formula 1 is bonded to a urethane polymer main chain.
[Chemical Formula 1]
-R1-C(=O)-O-R2
In the above chemical formula 1,
R1 is a C1-C10 alkylene group which may be substituted with one or more substituents selected from a carboxyl group, a carbonyl group, an OH group, and an ester group as a bond or functional group,
R2 is a C1-C10 alkyl group which may be substituted with one or more substituents selected from a carboxyl group, a carbonyl group, an OH group, and an ester group. In claim 1,
The first PVA binder is a polyvinyl alcohol having at least one functional group selected from the group consisting of a carboxyl group, an ammonium group, a sulfonium group, and a silanol group as a functional group, as a modified polyvinyl alcohol system, and the first PVA binder has a weight average molecular weight of 500 to 1,000, the second PVA binder is a polyvinyl alcohol having at least one functional group selected from the group consisting of a carboxyl group, an ammonium group, a sulfonium group, and a silanol group as a functional group, as a modified polyvinyl alcohol system, and the second PVA binder has a weight average molecular weight of 900 to 1,500, and the functional group of the first PVA binder is different from the functional group of the second PVA binder. In claim 1,
A material for an inkjet printer, characterized in that the first PVA binder and the second PVA binder of the ink-absorbing layer include 80 to 95 wt% of the first PVA binder and 5 to 20 wt% of the second PVA binder based on the total weight of the binders. (a) Step of preparing Tyvek substrate;
(b) a step of preparing a coating solution for a primer layer containing a polyurethane binder, pigment and solvent;
(c) a step of preparing a coating solution for an ink-absorbing layer comprising water, pigment, a first PVA binder, a second PVA binder, a cross-linking agent, an ink fixing agent, and a leveling agent.
(d) a step of manufacturing a primer layer by coating a coating solution for a primer layer on the above-mentioned substrate and drying it; and
(e) A method for manufacturing a material for an inkjet printer, comprising the step of coating a coating solution for an ink-absorbing layer on the primer layer and drying the coating solution to manufacture an ink-absorbing layer. In claim 8,
A method for manufacturing a material for an inkjet printer, characterized in that the coating solution for the primer layer contains 20 to 50 wt% of a solvent, 50 to 80 wt% of a pigment and an oil-based urethane binder. In claim 8,
A method for manufacturing a material for an inkjet printer, characterized in that the coating liquid for the ink-absorbing layer contains 20 to 50 wt% of water and 50 to 80 wt% of pigment, binder, cross-linking agent, ink fixing agent, and leveling agent. In claim 8,
A method for manufacturing a material for an inkjet printer, characterized in that the solvent of the coating liquid for the primer layer is at least one selected from the group consisting of methyl ethyl ketone (MEK), acetone, ethyl acetate (EA), isopropyl alcohol (IPA), and toluene (TOL).