JP2003312136A - Recording medium for ink jet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording medium for an ink jet printer which enables easy observation of the content of a recorded image either on a film viewer or in a place where the film viewer is not present. <P>SOLUTION: The recording medium which is subjected to recording by the ink jet printer has a substrate 23 of a colorless or blue transparent resin, an ink receiving layer 24 provided on one side of the substrate and a white layer 25 provided on the other side of the substrate. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium for an inkjet printer used for diagnosis or reference of X-ray images in the medical field, or a recording medium for an inkjet printer used for non-destructive X-ray inspection in various industrial fields. .

For example, in the medical field, digital information of an X-ray simple photographic image obtained by a computerized radiography (hereinafter referred to as “CR”) or a flat panel X-ray detector (hereinafter referred to as “FPD”) is It is drawn as an image on a monitor or film after undergoing appropriate image processing, and these are provided for image diagnosis, surgery planning conferences, medical education, and the like. That is, the present invention relates to a recording medium for an inkjet printer on which the X-ray image is recorded. In particular, the present invention relates to a recording medium for an inkjet printer, which is easy to handle and easy to diagnose and refer to.

[0003]

2. Description of the Related Art Transmission images have been conventionally used for X-ray image diagnosis in the medical field. That is, an image is formed on a film having a transparent resin as a support, and the film is hung on a light box (Shakasten) having a fluorescent lamp as a light source for image interpretation.

In recent years, there is no need to dispose of the used ink ribbon as in a thermal transfer system or a sublimation type printer, and an expensive silver resource such as a silver salt film is not used. BACKGROUND ART A printer is used to form a medical image on a film.

[0005]

By the way, when the film is removed from the Schaukasten, the illumination light from the back surface disappears, so that it becomes very difficult to observe the image formed on the film and grasp its contents.

That is, in a film sorting operation or in a place where there is no Schaukasten, for example, next to an inpatient bed,
There is a problem that it is difficult for doctors and patients to clearly see the X-ray image on the film.

The present invention has been made in view of the above problems, and provides a recording medium for an ink jet printer which enables easy observation of the content of a recorded image on a Schaukasten or in the absence of the Schaukasten. The purpose is to do.

[0008]

[Means for Solving the Problems] That is, the above problems are solved by the respective solving means described in (1) to (9) below.

(1) The invention according to claim 1 is a recording medium for an ink jet printer which is recorded by an ink jet printer, wherein a colorless or blue transparent resin support and one surface of the transparent resin support are provided. And a white layer provided on the other surface of the transparent resin support, and a recording medium for an inkjet printer.

The ink jet printer forms an image by continuously ejecting a small amount of liquid ink and landing it on a recording medium by utilizing, for example, the piezo effect of crystals according to an input electric signal. In addition, in order to draw an image that is most suitable for the purpose of use of the image, by using the optimum ink and recording medium, and by using an appropriate recording medium with an ink receiving layer, digital image signals obtained from CR and FPD can be obtained. It can be used to draw an X-ray image of good quality.

As described above, on the other surface of the colorless or blue transparent resin support having the ink receiving layer on one surface,
By using a recording medium for an ink jet printer characterized by having a white or pale bluish white layer, an X-ray image can be easily obtained whether or not Schaukasten is used. You will be able to observe.

(2) The invention according to claim 2 is characterized in that in (1), the light transmittance of the transparent resin support is 70% or more. In this way, by setting the light transmittance of the transparent resin support to 70% or more, an X-ray image can be easily obtained with sufficient brightness whether the Schaukasten is used or not. You will be able to observe.

(3) The invention according to claim 3 is characterized in that in (1) or (2), the white layer is made of a resin. As described above, by forming the white layer with the resin, it is possible to provide a recording medium for an ink jet printer which is elastic and excellent in handleability.

(4) The invention according to claim 4 is the same as (1) or (2), wherein the white layer is made of paper.
It is characterized by As described above, by providing the white layer of paper on the transparent resin support, it becomes possible to add the writing property to the recording medium for an inkjet printer.

(5) The invention according to claim 5 is (1) to
In (3), the light transmittance of the white layer is 10% or more 7
It is less than 0%. In this way, by setting the light transmittance of the white layer to 10% or more and less than 70%, it becomes possible to easily observe the X-ray image with sufficient brightness even when using Schaukasten.

(6) The invention according to claim 6 is (1) to
In (5), it is in the form of a sheet and has a size of 75 μm or more
It has a thickness of less than μm. As described above, by having a thickness of 75 μm or more and 250 μm or less, it is possible to maintain the strength of elasticity when handling a medium on which an X-ray image is printed.

(7) The invention according to claim 7 is (1) to
In (6), a monochrome image is recorded on the ink receiving layer. As described above, by recording a monochrome image on the ink receiving layer of the recording medium for an inkjet printer, the X-ray image can be easily observed whether the Schaukasten is used or not. You will be able to.

(8) The invention according to claim 8 is (1) to
In (6), a medical image is recorded on the ink receiving layer. As described above, by recording a medical image on the ink receiving layer of the recording medium for an ink jet printer, an X-ray image can be easily observed with or without using Schaukasten. You will be able to.

(9) The invention according to claim 9 is (1) to
In (6), a monochrome medical image is recorded on the ink receiving layer. As described above, by recording a monochrome medical image on the ink receiving layer of the recording medium for an ink jet printer, an X-ray image can be easily obtained whether the Schaukasten is used or not. You will be able to observe.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention relating to a recording medium for an ink jet printer will be described in detail below with reference to the drawings. The present invention is not limited to the specific examples shown in the description of the embodiments.

<Recording Medium for Inkjet Printer> Here, the recording medium for inkjet printer will be described. The recording medium for an inkjet printer of this embodiment has the following features (1) to (9).

(1) A colorless or blue transparent resin support, an ink receiving layer provided on one surface of the transparent resin support, and a white layer provided on the other surface of the transparent resin support. , Are included.

(2) In the above item (1), the light transmittance of the transparent resin support is 70% or more. (3) In the above (1) or (2), the white layer is made of resin.

(4) In the above (1) or (2),
The white layer is made of paper. (5) In the above (1) to (3), the white layer has a light transmittance of 10% or more and less than 70%.

(6) The above (1) to (5) are characterized in that they are sheet-like and have a thickness of 75 μm or more and 250 μm or less. (7) In the above (1) to (6), a monochrome image is recorded on the ink receiving layer.

(8) In the above (1) to (6), a medical image is recorded on the ink receiving layer. (9) In the above (1) to (6), a monochrome medical image is recorded on the ink receiving layer.

A recording medium for an ink jet printer will be described below with reference to FIGS. A recording medium for an inkjet printer used in this embodiment is
Characterized by drawing a substantially black image using an inkjet recording liquid, with rounded corners at four corners, 75 μm or more
A colorless or blue-colored transparent resin support 23 having a thickness of 250 μm or less has an ink receiving layer 24 of void type or the like on at least one surface, and a white layer on the other surface (FIGS. 1 to 1). 3).

That is, FIG. 3 shows a sectional view of a recording medium for an ink jet printer of this embodiment. The ink jet recording medium of the present embodiment is basically composed of three layers of a void type ink receiving layer 24, a transparent layer (transparent resin support 23) and an opaque layer (white layer 25) (Fig. 3).

The ink receiving layer 24 has a porosity of 40 to 90%.
Is a layer having a three-dimensional mesh structure. The three-dimensional network structure is formed of silica fine particles or organic fine particles having an average particle diameter of 20 nm or less and a water-soluble resin, and the weight ratio of the silica fine particles or organic fine particles to the water-soluble resin is 1.2: 1. It is preferably in the range of 12: 1.

The number of pores forming the voids of the three-dimensional network structure is 5
The average diameter is ˜40 nm, and the pores forming voids have a diameter of 0.
It has a pore volume of 3 to 1.0 ml / g. The silica fine particles are inorganic silicic acid and have ^{2 to} 3 silalol groups per 1 nm ^{2 of} the surface thereof, and the three-dimensional network structure is formed by the connection of secondary particles having a particle size of 10 to 100 nm in which the silica fine particles are aggregated. It preferably comprises a chain. Examples of the fine particles here include colloidal silica, calcium silicate, zeolite, kaolinite, halosite, muscovite, talc, calcium carbonate, calcium sulfate, aluminum oxide and the like. The water-soluble resin is preferably polyvinyl alcohol. Examples of preferable water-soluble resins are disclosed in Japanese Patent Application Laid-Open No. 07-276789 in addition to gelatin. The ink receiving layer 24 preferably has a specific surface area of 50 to 500 m ² / g.

In order to prevent the recording media for inkjet printers from sticking to each other when the recording media for inkjet printers are stacked, the average particle diameter is 5 to 100 μm.
Matte particles of m can be dispersed on the surface. Further, a surfactant may be added to prevent static electricity.
Also, coloring in blue is a preferred embodiment.

The transparent resin support 23 adjacent to the ink receiving layer 24 includes polyesters such as polyethylene phthalate, cellulose esters such as nitrocellulose and cellulose acetate, polysulfone, polyimide,
Polycarbonate or the like can be used. The term "transparent" in this embodiment means having a light transmittance of 70% or more. Regarding the transmittance, for example, the turbidimeter (integrating sphere photoelectric scattering photometer) Mode, manufactured by Tokyo Denshoku Gijutsu Center Co., Ltd.
l T-2600 A type (halogen lamp light source) allows easy measurement. This transparent resin support 23 may be colorless or colored in blue. The thickness of the transparent resin support 23 is preferably 10 μm or more and 200 μm or less. If it is too thin, it may cause strength problems, and it is 200 μm.
If the thickness exceeds, it becomes heavy and inconvenient to handle as a recording medium for an inkjet printer.

The blue color referred to here is 370 nm to 7 nm.
Ratio (Sb / Sv) between the average value (Sv) of the spectral transmittance in the visible light wavelength range of 60 nm and the average value (Sb) of the spectral transmittance in the blue light wavelength range of 380 nm to 450 nm
Is in the range of 0.30 to 0.50 and 300 nm to 45
It has a transmittance peak in the range of 0 nm.

In order to coat the ink receiving layer 24 on the transparent resin support 23, it is a preferred embodiment to process the surface of the transparent resin support 23. That is, the adhesion of the ink receiving layer 24 can be improved by performing corona discharge treatment, flame treatment, ultraviolet irradiation treatment, or the like. Alternatively, a gelatin layer or the like may be applied and then the ink receiving layer 24
Can be applied. It is a further preferred embodiment to add a hardening agent that strongly cross-links with gelatin, a blue coloring dye, and a fluorescent whitening agent that emits blue light upon receiving ultraviolet rays to this gelatin layer.

The white layer 25 provided on the surface of the transparent resin support 23 opposite to the ink receiving layer 24 includes polyesters such as polyethylene phthalate, cellulose esters such as nitrocellulose and cellulose acetate, and further polysulfone, polyimide and polycarbonate. Etc. can be used.

The white layer 25 of this embodiment has a light transmittance of less than 70% and 10% or more. The transmittance can be easily measured with a turbidimeter (integrating sphere photoelectric scattering photometer) Model T-2600 A type (halogen lamp light source) manufactured by Tokyo Denshoku Gijutsu Center Co., Ltd., for example. To make it opaque, calcium carbonate, barium carbonate, titanium oxide, zinc oxide, etc. can be added to the above resin. Then, adding a blue dye to give a light blue tint is a preferred embodiment. Further, it is a more preferable embodiment to use paper instead of resin. The reason is that it gives moderate friction and has a soft touch, does not have fingerprints, and can be additionally written. A comfortable white background can be provided by adding a fluorescent whitening agent to this paper. The thickness of the white layer 25 is preferably 5 μm to 200 μm.

The recording medium for an inkjet printer used in this embodiment is preferably in the form of a sheet. It is necessary to interpret a large number of images in a short time at medical sites. At this time, by making the four corners 22a of the square sheet recording medium into a round shape (see FIG. 2), it is possible to enhance safety when handling the recording medium for an inkjet printer.
It is also preferable to provide the notch 26 to identify the front and back. Also, in order to handle a recording medium for an ink jet printer having a certain size or more, the firmness of the waist is required,
Therefore, its thickness is preferably about 175 μm.

The inkjet image used in this embodiment is preferably a monochrome image. The monochromatic image is a monochromatic image, but a color tone based on black is preferable.
To obtain this image, the ink can be prepared by selecting an appropriate pigment or combining known dyes. The ink is liquid at room temperature and water-soluble. Further, it is a preferable method that inks having different densities and color tones are combined to smoothly change the density and cover a wide density area.

The white layer 25 has an opaque member. For example, the opaque member described in JP-A-9-254521 is preferably used. As the opaque member, high-quality paper, medium-quality paper, super calendered paper, uncoated paper such as glossy base paper, tracing paper, art paper, coated paper, lightweight coated paper, slightly coated paper, cast A coated paper such as coated paper, a plastic film, an opaque film containing a pigment, a film such as a foamed film, a resin-coated paper, a resin-impregnated paper, a non-woven fabric, a cloth and a composite thereof can be used.

The white layer 25 can be made of either porous or non-porous paper. Examples of the porous layer include wood pulp paper, Japanese paper, synthetic pulp paper, synthetic fiber paper, and the like, but it is preferable that the porous layer is composed mainly of wood pulp and pigment. The paper used in the white layer 25 is made from wood pulp as a main raw material and synthetic pulp obtained by kneading polypropylene as required, or synthetic fibers such as nylon, polyester, and polyolefin, glass fibers, ceramic fibers, and the like. As wood pulp, LBKP, LBSP, NBKP, NBSP, LD
Any of P, NDP, LUKP and NUKP can be used, but LBKP, NBSP, LBS with a large amount of short fibers
It is preferable to use more P, NDP and LDP.
However, the ratio of LBSP and / or LDP is 10 to 70.
Mass% is preferred.

Chemical pulp (sulfate pulp or sulfite pulp) having few impurities is preferably used as the above-mentioned pulp, and pulp having a whiteness improved by bleaching is also useful. In paper, sizing agents such as higher fatty acids and alkyl ketene dimers, white pigments such as calcium carbonate, talc and titanium oxide, paper strength enhancers such as starch, polyacrylamide and polyvinyl alcohol, optical brighteners, polyethylene glycols A water retention agent such as the above, a dispersant, and a softening agent such as quaternary ammonium can be appropriately added.

The freeness of pulp used for papermaking is JIS
200-500c according to Canadian Standard Method described in P 8121
c is preferable, and the fiber length after beating is JIS P 8
It is preferable that the sum of the 24 mesh residual mass% defined by 207 and the 42 mesh residual mass% is 30 to 70%. The mass% of the 4-mesh residue is preferably 20 mass% or less.

The basis weight of the paper is preferably from 50 to 250 g / m ^2, in particular 70~200g / m ² is preferred. The thickness of the paper is preferably 50 to 210 μm. The paper can be given a high smoothness by calendering at the papermaking stage or after the papermaking. Paper density is 0.7 to 1.2 g / m ² (JIS P 8
118) is common. Furthermore, the stiffness of base paper is JIS P
20-200 g is preferable under the conditions prescribed in 8143.

A commonly used surface sizing agent may be applied to the paper surface, and as the surface sizing agent, the same sizing agent as that which can be added to the base paper can be used. For example, JP-A-11-323771 and 11
-034483, JP-A 2000-094827, 2000-198266, and 2000-220096.
No. 2000-199196, various sizing agents may be used. The pH of the paper is JI
It is preferably 5 to 9 when measured by the hot water extraction method specified in SP-8113. Also, a backing layer can be provided on the surface opposite to the adhesive surface between the paper and the support.

The white layer 25 can also be formed by using a non-porous hydrophobic resin film. Examples of non-porous hydrophobic resin films include polyethylene terephthalate (PET) film, polyvinyl chloride (PV
C) film, polypropylene (PP) film, polystyrene (PS) film, etc. can be mentioned. These films are colored white and used as the white layer 25.

In this embodiment, as a method for whitening a thermoplastic resin to obtain a thermoplastic white film, first, inorganic fine particles having a difference in refractive index from the thermoplastic resin, so-called white pigment, is added, A method of whitening by scattering light by the difference in the refractive index, a thermoplastic resin (incompatible resin) different from the thermoplastic resin forming the film and incompatible, and / or a large amount of inorganic type There is a method in which fine particles are contained and fine bubbles (voids) are generated inside by stretching during film formation, and light is scattered by the voids to whiten. In the above method, light is scattered and whitened by the voids formed inside. As another method of forming voids inside, a foaming agent is contained in the polyester layer,
A method in which a void is generated mainly by foaming due to heating during extrusion, a method in which a void is generated by injecting a gas, or the like can be used.

In the present embodiment, the "inorganic fine particles" are titanium oxide, zinc oxide, zinc carbonate, calcium carbonate, magnesium carbonate, magnesium oxide,
Silica, talc, kaolin, lithium fluoride, calcium fluoride, barium sulfate, zinc sulfide, alumina, calcium phosphate, mica and the like can be used. These may be used alone or in combination of two or more. In the above method, among these particles, titanium oxide, zinc oxide, and zinc sulfide are more preferable, and titanium oxide particles are most preferable, from the viewpoint of overall effects such as whiteness and optical density. In the above method, talc, calcium carbonate and barium sulfate are more preferable. Also,
The inorganic fine particles may be in the form of porous or hollow porous, and further, in order not to impair the effects of the present embodiment, surface treatment is performed to improve dispersibility in the resin. It may be applied.

In the present embodiment, the average particle size of the inorganic fine particles in this method is preferably 0.05 to 5 μm, more preferably 0.07 to 3 μm, and further 0.1 to 2 μm. Some are most preferred. If the average particle size is out of the above range, uniform dispersion becomes difficult,
It is not preferable because the smoothness of the film surface may be deteriorated, and the whiteness and glossiness may be reduced due to the deterioration.

The amount of the inorganic fine particles added in this method is not particularly limited, but is preferably 1 to 35% by weight, more preferably 3 to 30% by weight, and further 5 to 25%.
Those in the range of wt% are most preferred. When the added amount is less than the above range, it is difficult to improve properties such as whiteness and optical density of the film, and when the added amount is more than the above range, the film is broken at the time of stretching or powder during post-processing. Inconvenience such as occurrence may occur.

In addition, the above-described method of whitening by containing voids in the white layer 25 is particularly effective when the laminated white film of this embodiment is used as a printing substrate.
It is more preferably adopted from the viewpoints of overall whiteness, lightness, cushioning property, heat insulating effect and the like, but among them, the method of incorporating an incompatible resin is most preferable. In particular, in an image that can be observed as both a transmission image and a reflection image, the image does not turn yellow during transmission observation (when observing the image with a film placed on a light box), which is particularly preferable.

The above "incompatible resin" means, for example, in a system melted with a thermoplastic resin forming a film in a measurement by a known method using a differential scanning calorimeter (DSC) or the like. It is a resin in which Tg corresponding to an incompatible resin is observed in addition to Tg corresponding to a plastic resin.

In particular, polyester is most preferable as the resin forming the film in terms of dimensional stability, mechanical properties, and interfacial adhesion with the heat-resistant resin layer to be laminated. Therefore, a resin that is incompatible with polyester as the incompatible resin will be described in detail below.

It is preferable that the incompatible resin has a large effect of being dispersed in the polyester in a particle form and forming a void in the polyester film by stretching. Also,
The melting point of such an incompatible resin is preferably lower than the melting point of polyester and higher than the temperature for orienting the film. From this point of view, the incompatible resin is preferably an olefin such as polyethylene, polypropylene, polybutene or polymethylpentene, polystyrene, polyphenylene sulfide, acryl, or a fluorine resin. These thermoplastic resins may be homopolymers or copolymers. Among these, olefins having a small critical surface tension are preferable,
Further, polypropylene and polymethylpentene are preferable. In particular, polymethylpentene is particularly preferable because it has a large difference in surface tension with polyester and has a high melting point, so that the effect of forming voids per addition amount is large.

In this embodiment, the content of the incompatible resin is not particularly limited, but is preferably 1 to 35% by weight, more preferably 2 to 30% by weight, and further 3 to 28% by weight.
Those in the range of wt% are most preferred. When the content is less than the above range, it is difficult to improve properties such as whiteness and optical density of the film. On the other hand, when the amount is more than the above range, not only the film becomes unsuitable as a base material for printing such as thermal transfer due to a decrease in the smoothness (glossiness) of the film surface, but also a problem such as film breakage occurs during stretching during film formation There is.

In the present embodiment, in order to bond the transparent resin support 23 and the white layer 25, the non-printed surface of the transparent resin support 23 (the surface opposite to the ink receiving layer 24) or the white to be bonded. A synthetic resin adhesive layer is provided on one surface of the layer 25 by using a laminator such as a general melt extrusion die, a T die, or a multi-layer simultaneous extrusion die, and at the same time, a method of superposing them while applying pressure is adopted. There is no limit.

As the synthetic resin constituting the synthetic resin adhesive layer, a thermosetting resin, a thermoplastic resin, a radiation curable resin or the like is used, but a thermoplastic resin is preferably used. The thermoplastic resin includes vinyl resin, polyolefin resin, polyester resin, styrene resin and the like, but polyolefin resin is preferably used. Examples of the polyolefin resin include the following substances.
High density polyethylene, low density polyethylene, medium density polyethylene, linear low density polyethylene and other polyethylene; isotactic, syndiotactic, atactic, mixtures thereof, random copolymers with ethylene, block copolymers, etc. Polypropylene: Other poly-3-methylpentene-1, polyethylene glycol terephthalate, polyvinyl chloride, polyvinylidene chloride, eval, ethylene vinyl acetate copolymer, etc. may be used alone or in combination.

Alternatively, the transparent resin support 23 and the white layer 2
In order to improve the adhesiveness with 5, the ionomer, the carbosyl-modified SBR latex, the colloidal alumina, or the ethylene / ethylene /
An anchor coat layer such as an acrylic acid copolymer may be provided. Further, the molten resin film may be subjected to a surface treatment or the like with ozone gas, and the non-printed surface of the transparent resin support 23 may be subjected to corona discharge treatment, ozone treatment, plasma treatment, ultraviolet irradiation treatment or flame treatment. Therefore, the adhesiveness may be improved.

Alternatively, a gelatin layer or the like may be coated on the non-printed surface of the transparent resin support 23 and a paper may be stuck thereon, and a film-forming agent that strongly cross-links with gelatin or blue coloring may be applied to the gelatin layer. It is a further preferred embodiment to add a dye or a fluorescent whitening agent that emits blue light upon receiving ultraviolet rays.

<Ink Used for Recording on Recording Medium for Inkjet Printer> When recording an image on the recording medium for inkjet printer of the present embodiment by an inkjet printer, dye ink, pigment ink, or the like is used. Various inkjet recording inks can be used.

As described above, on the other surface of the colorless or blue transparent resin support having the ink receiving layer on one surface,
By using a recording medium for an ink jet printer characterized by having a white or pale bluish white layer, the transmitted light is used as in the conventional case when the Schaukasten is used, and the indoor reflected light is used when the Schaukasten is not used. Thus, the X-ray image can be easily observed.

The light transmittance of the transparent resin support is 70%.
With the above, when the Schaukasten is used, the X-ray image can be easily observed with sufficient brightness. In addition, by forming the white layer with a resin, it is possible to provide a recording medium for an ink jet printer which has elasticity and excellent handleability. Further, by providing the white layer of paper on the transparent resin support in this manner, it becomes possible to add the writing property to the recording medium for an inkjet printer. In addition, the light transmittance of the white layer is 10
By setting the ratio to be not less than 70% and less than 70%, it becomes possible to easily observe the X-ray image with sufficient brightness even when using Schaukasten. Further, the sheet-like shape having a thickness of 75 μm or more and 250 μm or less can retain the strength of elasticity when handling a medium on which an X-ray image is printed.

[0062]

EXAMPLES The effects of the present invention will be specifically described below with reference to examples as specific examples of the present invention.

<Transparent Resin Support> Visible Light Density 0.10, 0.1
6, 0.30 blue colored polyethylene terephthalate with a thickness of 75 μm (hereinafter referred to as “Blue10 base”, “Blue16 base” and “Blue30 base”), uncolored polyethylene terephthalate with a thickness of 75 μm (hereinafter “Clear base”)
, And a 175 μm thick polyethylene terephthalate (hereinafter referred to as “Blu
e17 base ”. ) Was subjected to corona discharge treatment. A surfactant and a zinc oxide dispersion were added to a gelatin solution and coated on one side so that the amount of gelatin was ² g / m ² , and a backing layer for curling prevention and antistatic treatment was applied. The visible light density here is a diffusion density measured by an optical densitometer PDA-65 (manufactured by Konica Corporation), and an ND filter was used as a filter.

<Ink Receiving Layer> The composition of the coating liquid for the ink receiving layer 24 is shown below. 180 g of fine particle silica synthesized by the vapor phase method with an average primary particle size of 12 nm is 1000 ml of pure water
It was added to the inside and dispersed by a high speed homogenizer to obtain a blue transparent dispersion liquid. Next, in this silica aqueous dispersion, 2 of the exemplified cationic polymer Mor-1 is used as the cationic polymer.
Add 100 ml of 5% aqueous solution, add 0.01% of antifoaming agent DF-1 (polypropyleneoxy-polyethyleneoxy-disuccinate) to the coating solution, disperse with a high-speed homogenizer for 30 minutes, and obtain a pale white transparent A different dispersion was obtained. Next, the average degree of polymerization is 300, and the saponification degree is 98%.
1 ml of polyvinyl alcohol aqueous solution was added, and further 600 ml of 5% polyvinyl alcohol aqueous solution (containing 4% by mass of ethyl acetate) having an average degree of polymerization of 3500 and a saponification degree of 95%.
Was gradually added, followed by the addition of 4% borax aqueous solution # 100 ml as a viscosity improver, and further 20 ml of ethanol. 30 ml of the following Dispersion # 1 was added to this to prepare a colorant receiving layer solution # 1 which forms a layer having voids.

<Dispersion # 1> Solutions # 1 and # 2 having the following compositions were prepared, mixed, and dispersed by an ultrasonic disperser. Solution # 1 ・ Di-i-decyl phthalate: 3.0 g, ・ Ethyl acetate: 5 ml, Solution # 2 ・ Gelatin: 1.0 g, ・ Surfactant (Maruzen Pharmaceutical Co., Ltd. QC-100): 2.8
g, pure water: 22 ml, the coloring material receiving layer liquid # 1 obtained as described above was subjected to an easy adhesion treatment by glow discharge so that the wet film thickness was 240 μm on the recording surface side of the above film support. The sample was prepared by cooling the coating film temperature to 15 ° C. or lower and then drying with hot air at 40 ° C. for 150 seconds. Microscopic observation of this sample revealed that the size of secondary agglomerated particles was about 75 nm.

<White layer> Transparent resin support 23 and white layer 2
Using a polypropylene as a synthetic resin adhesive layer for adhering 5, a laminator equipped with a melt extrusion die,
The thickness of the synthetic resin adhesive layer was adjusted to 10 μm, and a high-quality paper having a basis weight of 40 g / m ² was coated with a white layer on the opposite side of the surface of the transparent resin support 23 coated with the ink receiving layer 24. 25
Pasted together.

Two types of high-quality paper, 75 μm and 100 μm, were prepared as the quality paper to be bonded to the transparent resin support 23.
Hereinafter, the 75 μm thick one is called “blank paper 75” and the 100 μm thick one is called “blank paper 100”. Furthermore, a white paper 75 was prepared by adding a fluorescent whitening agent to the composition and coloring it in a light blue color. Hereinafter, this is referred to as "light blue paper 75".

In the same manner as described above, 100 μm thick polyethylene terephthalate (hereinafter referred to as “white PET100”) was colored white on the side of the transparent resin support 23 opposite to the surface coated with the ink receiving layer 24. ) Sheet as white layer 25
Pasted together. The polyethylene terephthalate was whitened by the bubble method.

<Preparation of Inkjet Recording Medium> Those which do not satisfy the conditions of the present invention were prepared as “Comparative Example # 1”, “Comparative Example # 2” and “Comparative Example # 3”, and the conditions of the present invention were basically used. "Example # 1" to "Example # 1"
3 ”. Comparative Example # 1: An ink receiving layer 24 was coated on "Blue16 support", and a backing layer for preventing curling and charging was coated on the opposite surface. Comparative Example # 2: The "Blue30 support" was coated with the ink receiving layer 24, and the opposite surface was coated with a backing layer for curling prevention and antistatic treatment. Comparative Example # 3: "White PET100" was used as a support, and a backing layer for preventing curling and antistatic was applied on the surface opposite to the surface on which the ink receiving layer 24 was applied. -Example # 1: The ink receiving layer 24 was coated on the "Clear support", and "white paper 75" was attached to the opposite surface. -Example # 2: The ink receiving layer 24 was applied to the "Clear support", and "blank paper 100" was attached to the opposite surface. -Example # 3: The ink receiving layer 24 was coated on the "Clear support", and "fine blue paper 75" was attached to the opposite surface. -Example # 4: The ink receiving layer 24 was coated on the "Clear support", and "white PET100" was attached to the opposite surface. -Example # 5: The ink receiving layer 24 was coated on the "Blue10 support", and "white paper 75" was attached to the opposite surface. -Example # 6: The ink receiving layer 24 was coated on "Blue10 support", and "blank paper 100" was attached to the opposite surface. -Example # 7: The ink receiving layer 24 was coated on the "Blue10 support", and "fine blue paper 75" was attached to the opposite surface. -Example # 8: The ink receiving layer 24 was applied to the "Blue10 support", and "white PET100" was attached to the opposite surface. Example # 9: The ink receiving layer 24 was coated on the "Blue16 support", and "white paper 75" was attached to the opposite surface. Example # 10: Ink receiving layer 24 on "Blue16 support"
Was applied, and "white paper 100" was pasted on the opposite side. -Example # 11: Ink receiving layer 24 on "Blue16 support"
"Painted blue paper 75" was pasted on the opposite side. -Example # 12: Ink receiving layer 24 on "Blue16 support"
Was applied, and "white PET100" was pasted on the opposite side. Example # 13: Ink receiving layer 24 on "Blue17 support"
Was applied, and "white paper 75" was attached to the opposite side.

<Inkjet recording environment> The image used for evaluation is a phantom image in which image data obtained by performing CR (Computed Radiography) imaging is inkjet-recorded on the above-mentioned recording medium for inkjet printer by an inkjet printer.

This time, the CR was photographed using Regius 150 (Konica Corporation), and the image was ink-jet recorded using PM-950C (Epson Sales Corporation) for the ink jet printer.

The size of the image data is 2048 pixels × 20
The image data of 48 pixels has a resolution of 240 dots / 25.
When ink-jet recording was performed with an output size of 4 mm, an image was ink-jet recorded using a dedicated ink (YMCK) for the printer of Epson Sales Co., Ltd. Although a color image can be recorded here by using color ink, when the image data is a monochrome image, the recorded image is also monochrome.

<Measurement Method and Evaluation Method> Transmittance: Comparative Examples # 1 to # 3 and Example # described above
Integrating sphere photoelectric scattering photometer Model T-2600
The light transmittance was measured using DA type (Tokyo Denshoku Gijutsu Center Co., Ltd.). The transmittance of the transparent resin support 23 (“support transmittance” in Table 1) and the transmittance of the white layer (“white layer transmittance” in Table 1) were measured in advance before production of the inkjet recording medium. The transmittance in the inkjet recording medium (“total transmittance” in Table 1) is the transmittance measured after the inkjet recording medium was manufactured.

Recording medium thickness: As for the thickness of the inkjet recording medium, a transmission electron microscope HU-12 type (manufactured by Hitachi, Ltd.) was used, and a cross section of the recording medium for the inkjet printer of this embodiment was 500. Obtained from a cross-sectional photograph that was magnified twice (in Table 1, "recording medium thickness (μm)")
Corresponds to).

Image observability: Regarding image observability when observing an image in a transmission observation environment (transmission observability) and image observability when observing an image in a reflection observation environment (reflection observability) Then, visual evaluation was performed. Regarding the transmission observation environment, an image was applied to a light box with an average brightness of 2700 cd / m ² and observed with the indoor illuminance being as low as possible. Regarding the reflection observation environment, the average illuminance is 52
Images were observed in a 0 lx room without using auxiliary light. A comprehensive image quality evaluation was performed as a diagnostic image in consideration of graininess, sharpness, gradation and color tone. The evaluation judgment is
Judgment was made by four-level evaluation of “◎”, “○”, “△”, and “×”, and the evaluation criteria were (◎: extremely good, ○: good, Δ: slightly bad,
The evaluation results correspond to the items of "transmission observability" and "reflection observability" in Table 1.

Ease of handling: The ease of handling of the ink jet recording medium was evaluated. As for evaluation items, the overall usability was evaluated by examining whether the film could be hung on a light box, the weight feeling when holding the film, the strength of the body, etc. In addition, evaluation judgment is "◎""○"
Judgment is made by a four-level evaluation of "△" and "×"
(⊚: extremely good, ◯: good, Δ: slightly bad, x: bad), and the evaluation result corresponds to the item “easy to handle” in Table 1.

<Measurement Results and Evaluation Results> When the evaluation was carried out in the above manner, the results shown in Table 1 were obtained.

[0078]

[Table 1]

Therefore, the following three conclusions became clear. -Relationship between transmittance and image observability: Regarding the transmittance, the support preferably has 70% or more, and the white layer preferably has less than 70% and 10% or more. When the transmittance of the support is low or the transmittance of the white layer is high, the amount of reflected light (particularly, the amount of reflected light inside the support) decreases, so the diagnostic ability (reflection observation property) of the reflected image is impaired, and the white When the transmittance of the layer is low, the amount of transmitted light is small and the diagnostic ability (transmission observability) of the transmitted image is impaired.

Further, regarding the transmittance of the entire recording medium,
5% to 60% is preferable. However, 30% as a transparent image
From the viewpoint of observability, 5% to 40% is preferable as the reflection image. It is possible to achieve both transmission observation and reflection observation among the contradictory properties that the observation ability of a transmission image is improved by coloring blue and the observation ability of a reflection image is decreased by coloring blue. Range is 30-40
%Met.

Relationship between recording medium thickness and image observability: The recording medium thickness is preferably 100 μm or more and 250 μm or less.
When the support is thick, the light scattering inside the support becomes large, which impairs the diagnostic ability of the reflected image (reflection observation property). When the white layer is thick, the transmitted light amount is significantly reduced and the diagnostic ability of the transmitted image is reduced. It was found that the (transmission observability) was impaired. Although the thickness of the recording medium changes depending on the thickness of the ink receiving layer 24, it has been found that the thickness of the recording medium is preferably in the above range from the viewpoint of the amount of absorbed ink and brittleness.

Relationship between recording medium thickness and ease of handling: The thickness of the recording medium is preferably 100 μm or more and 250 μm or less. Especially, when the recording medium is 100 μm or less, the elasticity of the recording medium is weak,
It is difficult to diagnose the image by holding the film in your hand. Also, 250
If it is more than μm, the recording medium is thick and it is difficult to separate the film.
Further, the transportability of the printer becomes a problem, which is not preferable.

Relationship between image observability and monochrome image: As described above, by recording a monochrome image on the recording medium for an ink jet printer of the present invention, which has good results in terms of transmission observability and reflection observability, It was found that the effects of the invention were more prominent and particularly good results were obtained. Gray (black) has a higher density contrast resolution that can be visually recognized by humans than other monochromatic colors (RGB), and the required image quality level becomes strict, but the transparent resin support 23 and the white layer 25 included in the recording medium for an inkjet printer are provided.
It is considered that the effect of the invention of the present application was more prominent by keeping the light transmittance in 2 within the predetermined range.

Relationship between image observability and medical image: As described above, the recording medium for an ink jet printer of the present invention has good results in terms of transmission observability and reflection observability.
It was found that the effects of the present invention were more prominent by recording medical images, and particularly good results were obtained. In particular, since medical images are used for diagnosis and the like, it is difficult for the images to be viewed (color tone, etc.) or easy to handle, but the recording medium for inkjet printers is colored white or blue, or for inkjet printers. It is considered that the effect of the present invention was more prominent by keeping the thickness of the recording medium within the predetermined range.

Relationship between image observability and monochrome medical image: As described above, a monochrome medical image is recorded on the recording medium for an inkjet printer of the present invention which has good results in terms of transmission observation and reflection observation. By doing so, it was found that the effect of the present invention was more prominent, and a better result was obtained. If one of the above "image quality level" and "ease of viewing or handling of the image" is lacking, it is not suitable for use as a medical image and a diagnostic image, and by having both features at the same time, the present application It is considered that the effects of the invention were more prominent.

[0086]

As described above in detail, according to the present invention, the content of the recorded image can be easily observed even on the Schaukasten or in the absence of the Schaukasten. A recording medium for an inkjet printer can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing a recording medium for an inkjet printer and a configuration of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a state of a recording medium for an inkjet printer according to an embodiment of the present invention.

FIG. 3 is a configuration diagram showing a cross-sectional configuration of a recording medium for an inkjet printer according to an embodiment of the present invention.

[Explanation of symbols]

20 Recording medium for inkjet printer 23 Transparent resin support 24 Ink receiving layer 25 white layer

Claims (9)

[Claims] 1. A recording medium for an inkjet printer, which records by an inkjet printer, comprising: a colorless or blue transparent resin support; an ink receiving layer provided on one surface of the transparent resin support; A white layer provided on the other surface of the resin support,
A recording medium for an inkjet printer, comprising: 2. The light transmittance of the transparent resin support is 70%.
The recording medium for an inkjet printer according to claim 1, which is the above. 3. The recording medium for an inkjet printer according to claim 1, wherein the white layer is made of resin. 4. The recording medium for an inkjet printer according to claim 1, wherein the white layer is made of paper. 5. The light transmittance of the white layer is 10% or more 70
It is less than%, Claim 1 thru | or Claim 3 characterized by the above-mentioned.
A recording medium for an ink jet printer according to any one of 1. 6. A sheet-like shape, 75 μm or more and 250 μm
The recording medium for an inkjet printer according to any one of claims 1 to 5, wherein the recording medium has a thickness of m or less. 7. The recording medium for an inkjet printer according to claim 1, wherein a monochrome image is recorded on the ink receiving layer. 8. The recording medium for an ink jet printer according to claim 1, wherein a medical image is recorded on the ink receiving layer. 9. The method according to claim 1, wherein a monochrome medical image is recorded on the ink receiving layer.
A recording medium for an ink jet printer according to any one of 1.