JPH08174995A - Recording medium, ink jet recording method using the same, and image forming method - Google Patents

Abstract

PURPOSE: To provide a recording medium in which conveying irregularity such as duplicate feeding, slip is less apt to occur even in a conveying type by an automatic sheet feeder and which has excellent printing quality level. CONSTITUTION: An ink receiving layer is provided at least on one surface of a base material. Beek smoothness of each of both front and rear surfaces is 5 to 800sec, and the difference of the smoothnesses of the front and rear surfaces is 0 to 280sec.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium suitable for ink jet recording, an ink jet recording method using the same and an image forming method.

[0002]

2. Description of the Related Art Ink jet recording methods include various ink ejection methods such as an electrostatic suction method, a method in which a piezoelectric element is used to mechanically vibrate or displace ink, ink is heated to foam, and the pressure is used. In this method, small droplets of ink are generated and ejected, and part or all of them are attached to a recording material such as paper or a plastic film coated with an ink receiving layer for recording. It is attracting attention as a method that can generate high-speed printing and multicolor printing with less noise.

As the ink used in the ink jet recording system, one mainly containing water is used in terms of safety and recording characteristics, and it is a multi-valued ink for preventing nozzle clogging and improving ejection stability. Alcohols are often added.

Conventionally, various types of paper, OHP film, glossy paper, cloth and the like have been developed and provided to users as recording media used for ink jet recording.

At the same time, the method of transporting the printer main body has changed, and the transport of recording media by an automatic sheet feeder (hereinafter abbreviated as ASF) has become the mainstream, instead of the conventional manual transport.

As a recording medium conventionally used for ink jet recording, as described in JP-A-60-220750, a hydrophilic property of a water-soluble polyvinyl alcohol having a saponification degree of 70 to 90 mol% on a polyester film. Overhead projector with coating
There are many examples such as recording sheets for (hereinafter abbreviated as OHP).

[0007]

In recent years, speeding up of recording,
Along with the improvement in the performance of inkjet recording apparatuses such as multicolor printing, more advanced and broader characteristics are required for inkjet recording media.

That is, (1) the ink absorption capacity is high (the absorption capacity is large, the absorption time is fast), (2) the optical density of the dots is high, and the periphery of the dots is not blurred. (3) the dot shape is a perfect circle. (4) The change in characteristics due to changes in temperature and humidity is small and curling does not occur (5) Blocking does not occur (6) Images are stable for long-term storage Do not change (especially
(High-temperature and high-humidity environment) (7) It is required to simultaneously satisfy characteristics such as stable and long-term storage of the recording medium without deterioration (especially under high-temperature and high-humidity environment).

Further, as the recording speed, image density, color, and ink diversification have increased,
Various recording media have been required.

Further, the mainstream paper feeding method on the printer body side starts to change from manual feeding to ASF feeding,
In order for the printer body side to pick up the recording medium smoothly, the following performance has been newly demanded. (1) The recording medium is conveyed smoothly (two recording mediums,
(3) Multi-feeding with 3 sheets, slipping and not being conveyed), (2) When the recording medium is picked up, the recording medium is not scratched by the pickup roller, (3) The recording medium is picked up At this time, the recording medium stacked under the picked-up recording medium is not scratched, and (4) the powder of the additive such as filler does not fall off the surface of the recording medium.

As the ink jet recording sheet described in Japanese Patent Publication No. 6-55542, a recording sheet is proposed in which the Bekk smoothness of the ink receiving layer is 130 seconds to 800 seconds. In the medium, when the smoothness on the opposite side is very large or small, the transportability by ASF is not sufficiently satisfactory.

ASF as a recording medium for ink jet
A recording medium optimized for transportation has not been developed or sold yet.

Therefore, an object of the present invention is to provide a recording medium suitable for ink jet recording, which is excellent in print quality and which is unlikely to cause conveyance unevenness such as double feeding and slipping in the ASF conveying system, and an ink jet recording method using the same. An image forming method is provided.

[0014]

The above object can be achieved by the present invention described below.

That is, the present invention has an ink receiving layer on at least one surface of a base material, and has a surface smoothness of 5 on both front and back surfaces.
Seconds or more and 800 seconds or less, and the difference in smoothness between the front and back surfaces is 0
The recording medium is characterized in that it is not less than 2 seconds and not more than 280 seconds.

More preferably, both surface smoothness of the front and back surfaces is 5 seconds or more and 500 seconds or less, and more preferably both surface smoothness of the front and back surfaces is 5 seconds or more and 300 seconds or less.

Further, the present invention is an ink jet recording method, which is an image forming method, characterized in that ink is ejected from an orifice of a recording head in accordance with a recording signal to perform recording on a recording medium.

More preferably, the liquid medium component of the ink is
Including that the composition is mainly composed of water and water-miscible glycols or glycol ethers, that the ink is cyan, magenta, yellow, and black ink, and that the ink is ejected by thermal energy.

[0019]

The present inventors, while developing a recording medium suitable for ink jet recording using ASF transportation, found that the above-mentioned recording medium has excellent transportability, and completed the present invention. It is a thing.

That is, a recording medium suitable for a recording apparatus using ASF transport has an ink receiving layer on at least one surface of a substrate, and has a surface smoothness of 5 seconds or more and 800 seconds or less on both front and back surfaces, and The difference in smoothness between the front and back surfaces is 0 seconds or more and 280 seconds or less, more preferably the surface smoothness on the front and back surfaces is 5 seconds or more and 500 seconds or less, and more preferably the surface smoothness on the front and back surfaces is 5 seconds. The recording medium is such that the time is 300 seconds or less.

Here, the difference in smoothness between the front surface and the back surface is an absolute value, and it is not always necessary that the smoothness of either one of the front surface and the back surface is high.

Next, the present invention will be described in more detail with reference to preferred embodiments.

The base material of the recording medium used in the present invention includes high-quality paper, medium-quality paper, art paper, bond paper, recycled paper, baryta paper, cast coated paper, cardboard paper and the like, and polyethylene terephthalate. , Diacetate, triacetate, cellophane, celluloid, polycarbonate
, Polyimide, polyvinyl chloride, polyvinylidene chloride, polyacrylate, polyethylene, a film made of a plastic such as polypropylene, or a plate, a glass plate, or cotton, rayon, acrylic, silk, a cloth such as polyester can be used. Of course, it is not limited to these.

The surface of the base material may be a smooth surface, unevenness, or may be transparent or translucent. Further, two or more kinds of these base materials may be bonded to each other.

Further, a back coat layer such as a mat layer and a peeling adhesive layer may be provided on the side opposite to the printed surface, and an adhesive layer may be provided on the printed surface after printing.

It is appropriately selected from the above-mentioned base materials depending on the recording purpose of the recording medium, the use of the recorded image, or various conditions such as adhesion to the composition coated on the recording medium.

An OHP film can be formed by using a translucent material such as a plastic film as the base material, and a glossy paper can be formed by using an opaque material such as paper as the base material. Further, depending on the purpose, the base material, the ink receiving layer and the like may be colored.

The material forming the ink receiving layer and the back coat layer is not particularly limited, but is particularly limited as long as it can accept a so-called aqueous ink and exhibits solubility or affinity for the aqueous ink. However, polyvinylpyrrolidone, polyvinyl alcohol, anion-modified polyvinyl alcohol, cation-modified polyvinyl alcohol, polyurethane, carboxymethyl cellulose, polyester, polyacrylic acid (ester),
Examples thereof include synthetic resins such as hydroxyethyl cellulose, cationized hydroxyethyl cellulose, melamine resin, and modified products thereof, and natural resins such as albumin, gelatin, casein, starch, cationized starch, gum arabic, and sodium alginate. ,
It is not limited to these. It is also possible to use a plurality of these materials at the same time.

Further, a water-dispersible resin may be used as a material for the ink receiving layer, and examples thereof include polyvinyl acetate, ethylene-vinyl acetate copolymer, polystyrene, styrene- (meth) acrylic acid ester copolymer, and (meth) acrylic. Acid ester-based polymer, vinyl acetate- (meth) acrylic acid (ester) copolymer, poly (meth) acrylamide, (meth) acrylamide-based copolymer, styrene-isoprene copolymer, styrene-butadiene copolymer, ethylene A large number of propylene copolymers, polyvinyl ethers and the like can be enumerated, but of course the present invention is not limited to these. A plurality of these water-soluble resins and water-dispersible resins may be used at the same time.

Further, for the purpose of improving the image storability,
You may further contain a cationic compound.

The cationic compound is not particularly limited as long as it contains a cationic moiety in the molecule, and examples thereof include monoalkylammonium chloride, dialkylammonium chloride, tetramethylammonium chloride, trimethylphenylammonium chloride and ethylene. Quaternary ammonium salt-type cationic surfactants such as oxide-added ammonium chloride, or amine salt-type cationic surfactants, and further alkylbetaines containing a cationic moiety, imidazolium-betaine, alanine-based surfactants, etc. An amphoteric surfactant may be used.

As the polymer or oligomer, a cation-modified polyacrylamide or a copolymer of acrylamide and a cationic monomer, polyallylamine, polyamine sulfone, polyvinylamine, polyethyleneimine, polyamide-epichlorohydrin resin, polyvinylpyridinium halide, etc. may be used. Can be mentioned.

Further, vinylpyrrolidone-based monomers alone or copolymers with other general monomers, vinyloxazolidone-based monomers alone or copolymers with other general monomers, and vinylimidazole-based monomers are used. Examples thereof include a single substance or a copolymer with another general monomer.

Examples of the above-mentioned general monomers include methacrylate, acrylate, acrylonitrile, vinyl ether, vinyl acetate, ethylene and styrene.

The above-mentioned cationic compounds are preferably used, but they may be used alone or in combination of two or more, and a low molecular weight cationic substance and a high molecular weight cationic substance may be used in combination.
Of course, it is not limited to these.

Of course, in the constitution of the present invention, the above-mentioned cationic compound is not an essential component but merely shows an auxiliary role.

Furthermore, a cross-linking agent may be included, such as, but not limited to, methylolated melamine, methylolated urea, methylolated hydroxypropylene urea, and isocyanate.

Various fillers and additives may be used in combination within a range not hindering the achievement of the object of the present invention in order to make the surface smoothness of the ink receiving layer and the film proper.

Examples of fillers are silica, alumina, aluminum silicate, calcium silicate, magnesium silicate, basic magnesium carbonate, talc, clay, ummo, haodrotalcite, calcium carbonate, barium carbonate, titanium oxide, Examples thereof include, but are not limited to, zinc oxide, plastic pigments such as polyethylene, polystyrene, and polyacrylate, glass beads, and the like.

When the smoothness of the recording medium is less than 5 seconds, the ASF transport causes the recording medium to be transported without any problem.
There is a problem that the recording medium located under the conveyed recording medium is damaged.

If the smoothness exceeds 800 seconds, the adhesion between recording media is increased, and there is a problem of "double feeding" in which two or three recording media are frequently fed. When the smoothness is more than 500 seconds, double feeding occurs about 3 out of 50 times when transported by ASF. If the smoothness exceeds 300 seconds, when the halftone is printed, the trace of the pickup roller is slightly left on the recording medium. further,
If the difference in smoothness between the front and back surfaces deviates from 0 second to 280 seconds, problems such as scratches on the recording medium surface and double feeding may occur.

As a concrete example of the additive to be used,
Various surfactants, dye fixing agents (waterproofing agents), antifoaming agents, antioxidants, fluorescent whitening agents, ultraviolet absorbers, dispersants, viscosity modifiers, pH modifiers, antifungal agents, plasticizers. To be These additives may be arbitrarily selected from conventionally known compounds according to the purpose.

In preparing the ink receiving layer or the backcoat layer of the recording medium of the present invention, first, the above composition, together with other additives as necessary, water or alcohol, polyhydric alcohols, or the like is used. Is dissolved or dispersed in an appropriate organic solvent to prepare a coating liquid.

The obtained coating liquid is applied, for example, to a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a bar coater. Method, size press method, spray coat method, gravure coater method, carter coater method and the like. After that, it is dried using, for example, a hot air drying oven or a heating drum to obtain the recording medium of the present invention.

[0045] The coating amount of the coating liquid for forming the ink receiving layer, 0.2 to 50 g / m ² as the total amount, more preferably in the range of 1 to 30 g / m ^2. When the coating amount is small, a part of the substrate may be exposed on the surface. If the coating amount is less than 0.2 g / m ² ,
Compared with the case where the ink receiving layer is not provided, the effect is less in terms of the color developability of the coating material. On the other hand, when it is provided over 50 g / m ² , curling is remarkable especially in a low temperature and low humidity environment. . When the coating amount is expressed by thickness, the coating amount is 0.5
A range in which the thickness is about 100 μm is suitable.

The coating amount of the coating liquid for forming the backcoat layer may be approximately the same as the coating amount of the ink receiving layer.

As the ink itself for carrying out ink jet recording and image formation on the recording medium described above, known inks can be used without any problems. As the recording agent, a direct dye, an acid dye, a basic dye, a reactive dye, a water-soluble dye typified by an edible dye, a dispersible dye, and a pigment can be used. If there is no particular limitation, it can be used.

Such water-soluble dyes or dispersible dyes and pigments are generally contained in conventional ink in an amount of about 0.1.
It is used in a proportion of about 20% by weight, and the proportion may be the same in the present invention.

The solvent used in the water-based ink used in the present invention is water or a mixed solvent of water and a water-soluble organic solvent, and a particularly preferable solvent is a mixed solvent of water and a water-soluble organic solvent. The organic solvent contains a polyhydric alcohol, which is a water-miscible glycol having an effect of preventing ink drying.

In the present invention, when forming a color image,
In order to prevent bleeding (irregular bleeding) between adjacent black and color images, black ink having high surface tension and yellow, magenta and cyan inks having low surface tension are colored. -Ink is preferably used.

The surface tension of the black ink is 40 to 55.
The range of dyne / cm is preferable, and the surface tension of the color ink is preferably within the range of 30 to 40 dyne / cm.

The method for recording by applying the above-mentioned ink to the above-mentioned recording medium is preferably an ink jet recording method, and this method is a range, in which the ink is effectively separated from the nozzle. Any method may be used as long as it can apply ink to the recording medium. In particular, according to the method described in Japanese Patent Laid-Open No. 54-59936, an ink-jet system which is subjected to the action of thermal energy causes a rapid volume change, and the action force due to this state change ejects the ink from the nozzle. Can be used effectively.

An example of an inkjet recording apparatus suitable for recording using the recording medium of the present invention will be described below. An example of a head configuration that is a main part of the apparatus is shown in FIGS.
And shown in FIG.

The head 13 is made of glass, ceramics or a plastic plate having a groove 14 through which ink passes, and is used as a heat-generating head 15 for heat-sensitive recording (a head is shown in the drawing, but is not limited to this). It is obtained by bonding and. The heating head 15 includes a protective film 16 made of silicon oxide, aluminum electrodes 17-1 and 17-.
2. A heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate 20 having a good heat dissipation property such as alumina.

The ink 21 has a discharge orifice (fine hole) 2
2, the meniscus 23 is formed by the pressure P.

Now, when an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact therewith,
The meniscus 23 is projected by the pressure, the ink 21 is ejected, becomes a recording droplet 24 from the orifice 22, and flies toward the recording medium 25. FIG. 3 shows an external view of a multi-head in which many heads shown in FIG. 1 are arranged. The multi-head is manufactured by closely contacting a glass plate 27 having a multi-groove 26 and a heating head 28 similar to that described in FIG.

Incidentally, FIG. 1 shows the head 1 along the ink flow path.
3 is a sectional view of FIG. 3, and FIG. 2 is a sectional view taken along the line AB of FIG. 1.

FIG. 4 shows an example of an ink jet recording apparatus incorporating such a head. In FIG. 4, 61
Is a blade serving as a wiping member, one end of which is held by a blade holding member to be a fixed end, which is in the form of a cantilever. The blade 61 is disposed adjacent to the recording area by the recording head, and in the case of this example, is held in a protruding form in the movement path of the recording head. Reference numeral 62 denotes a cap, which is disposed at a home position adjacent to the blade 61, and has a configuration in which it moves in a direction perpendicular to the moving direction of the recording head and contacts the ejection port surface to perform capping. Further, 63 is an ink absorber provided adjacent to the blade 61, and like the blade 61,
The recording head is held in a protruding form in the moving path of the recording head.
The blade 61, the cap 62, and the absorber 63 constitute a discharge recovery unit 64, and the blade 61 and the absorber 6
By the means 3, water, dust and the like are removed from the ink ejection port surface.

Reference numeral 65 denotes a recording head having ejection energy generating means for ejecting ink onto a recording medium facing the ejection port surface on which ejection ports are arranged for recording, and 66 a recording head 65 having the recording head 65 mounted thereon. It is a carriage for moving the. The carriage 66 slidably engages with the guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and its adjacent area.

Reference numeral 51 designates a paper feed section for inserting a recording medium, and 5
A paper feed roller 2 is driven by a motor (not shown). With these configurations, the recording medium is fed to the position facing the ejection port surface of the recording head, and as the recording progresses, the sheet discharge roller 53 is arranged and the sheet is discharged.

In the above structure, when the recording head 65 returns to the home position after recording is completed, the cap 62 of the head recovery section 64 is retracted from the movement path of the recording head 65, but the blade 61 is projected into the movement path. There is. As a result, the ejection port surface of the recording head 65 is wiped. When the cap 62 comes into contact with the protruding surface of the recording head 65 to perform capping, the cap 62 moves so as to protrude into the moving path of the recording head.

When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are in the same position as the above-mentioned wiping position. As a result, the ejection opening surface of the recording head 65 is wiped even during this movement.

The above-mentioned movement of the recording head to the home position is performed not only at the end of recording or at the time of ejection recovery, but also at the home adjacent to the recording area at a predetermined interval while the recording head moves in the recording area for recording. The wiper is moved to the position, and the wiping is performed along with the move.

[0064]

The present invention will be described in more detail with reference to the following examples. In the text, “part” or “%” is based on weight unless otherwise specified.

Example 1 Polyvinyl alcohol (trade name: PVA217, manufacturer: manufactured by Kuraray, saponification degree: about 88 mol%, polymerization degree: about 17)
00) of 10% aqueous solution, 1.2 parts of silica fine particles (trade name: Sylysia 470, manufacturer: Fuji Silysia Chemical Ltd., average particle size: 12 μm) are dispersed in 100 parts of 10% aqueous solution, and a coating solution is applied to the wire bar. -, Using a polyethylene terephthalate film (trade name: Lumirror, manufacturer: Toray, thickness: 100 μm), the coating thickness after drying is 10 μm
And then dried at 120 ° C for 3 minutes,
Next, the same coating liquid as above was applied to the back surface and a back coat layer was formed under the same conditions to prepare the recording medium of the present invention.

Color recording was carried out on the above recording medium under the following conditions using an ink jet recording apparatus in which the ink having the following composition was used to foam the ink by thermal energy and eject the ink.

Ink composition (Bk) Direct Black 19 3 parts Glycerin 6 parts Ethylene glycol 5 parts Urea 5 parts Isopropyl alcohol 3 parts Water 78 parts The surface tension of this ink was about 45 dyne / cm.

Ink composition (Y, M, C) Dye 4 parts Glycerin 7 parts Thiodiglycol 7 parts Urea 7 parts Acetylene glycol 1.5 parts Water 73.5 parts The surface tension of this ink is about 35 dyne / cm. It was

Dye Y: Direct Yellow-86 M: Acid Red 23 C: Direct Blue 199 Recording Conditions Ejection Frequency: 4 KHz Ejection Droplet Capacity: 45 pl Recording Density: 360 DPI Maximum Single Color Ink Amount: 8 nl / mm ² Transport Method: ASF (Auto Sheet Feeder)

Example 2 In Example 1, the resin forming the ink receiving layer was polyvinyl alcohol (trade name: PVA405, manufacturer: Kuraray Co., saponification degree: about 81.5 mol%, polymerization degree: about 500). A recording medium was prepared in exactly the same manner as in Example 1 except that the above was used, and color recording was carried out by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Example 3 A recording medium was prepared in the same manner as in Example 1 except that the amount of silica fine particles added was 0.8 parts.
Color recording was performed by an ink jet recording apparatus in which the ink was foamed by thermal energy and ejected.

Example 4 A recording medium was prepared in the same manner as in Example 2 except that the amount of silica fine particles added was 0.8 parts.
Color recording was performed by an ink jet recording apparatus in which the ink was foamed by thermal energy and ejected.

Example 5 A recording medium was prepared in the same manner as in Example 1 except that the amount of silica fine particles added was 0.4 parts.
Color recording was performed by an ink jet recording apparatus in which the ink was foamed by thermal energy and ejected.

Example 6 A recording medium was prepared in the same manner as in Example 2 except that the amount of silica fine particles added was 0.4 parts.
Color recording was performed by an ink jet recording apparatus in which the ink was foamed by thermal energy and ejected.

Example 7 Recording was carried out in the same manner as in Example 1 except that silica fine particles (trade name: Syropure 35, manufacturer: Fuji Silysia Chemical Ltd., average particle size: 8 μm) were used in Example 1. A medium was prepared, and color recording was performed by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Example 8 Recording was carried out in the same manner as in Example 3 except that silica fine particles (trade name: Syropure 35, manufacturer: Fuji Silysia Chemical Ltd., average particle size: 8 μm) were used in Example 3. A medium was prepared, and color recording was performed by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Example 9 A recording medium was prepared in the same manner as in Example 1 except that polyvinyl acetal (trade name: KW-1, manufactured by Sekisui Chemical Co., Ltd.) was used as the resin constituting the ink receiving layer. Then, color recording was performed by an ink jet recording apparatus that causes the ink to foam by thermal energy and eject the ink.

Example 10 A recording medium was prepared in the same manner as in Example 1 except that hydroxyethyl cellulose (trade name: AL-15, manufactured by Fuji Chemical) was used as the resin constituting the ink receiving layer. Then, color recording was performed by an ink jet recording apparatus that causes the ink to foam by thermal energy and eject the ink.

Example 11 A recording medium was prepared in the same manner as in Example 2 except that the back coating layer on the back surface was formed by using the coating liquid used in Example 1, and the thermal energy was changed. Color recording was performed by an ink jet recording apparatus in which the ink was foamed to eject the ink.

Example 12 A recording medium was prepared in the same manner as in Example 5 except that the back coating layer on the back surface was formed by using the coating solution used in Example 3, and the thermal energy was changed. Color recording was performed by an ink jet recording apparatus in which the ink was foamed to eject the ink.

Example 13 In Example 1, the amount of silica fine particles added to the ink receiving layer was 2.0 parts, and the back coat layer on the back surface was formed using the coating liquid used in Example 3. Example 1 except that
A recording medium was prepared in exactly the same manner as described above, and color recording was performed by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Example 14 In Example 1, the amount of the silica fine particles added to the ink receiving layer was 0.2 part, and the back coat layer on the back surface was formed using the coating liquid used in Example 5. Example 1 except that
A recording medium was prepared in exactly the same manner as described above, and color recording was performed by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Example 15 Example 5 was repeated except that the coating liquid used in Example 5 was used for forming the ink receiving layer and the coating liquid used in Example 8 was used for forming the back coat layer on the back surface. A recording medium is prepared in exactly the same manner as described above, and a color is formed by an ink jet recording apparatus in which the ink is foamed by thermal energy and ejected.
Recordings were made.

Example 16 A recording medium was prepared in the same manner as in Example 14 except that the coating liquid used for forming the ink receiving layer in Example 14 was used for forming the ink receiving layer and the back coat layer on the back surface. Then, color recording was performed by an ink jet recording apparatus that causes the ink to foam by thermal energy and eject the ink.

Comparative Example 1 In the same manner as in Example 5, except that silica fine particles (trade name: Sylysia 450, manufacturer: Fuji Silysia Chemical Ltd., average particle size: 5 μm) were used in Example 5. A recording medium was prepared, and color recording was performed by an inkjet recording device in which the ink was foamed by thermal energy and the ink was ejected.

Comparative Example 2 A recording medium was prepared in the same manner as in Example 1 except that the coating liquid used in Comparative Example 1 was used to form the back coat layer on the back surface of Example 1, and the heat treatment was performed. Color recording was performed by an ink jet recording apparatus in which ink was foamed by energy and ejected.

Comparative Example 3 A recording medium was prepared in the same manner as in Example 5 except that the coating liquid used in Comparative Example 1 was used to form the back coat layer on the back surface in Example 5, and the heat treatment was performed. Color recording was performed by an ink jet recording apparatus in which ink was foamed by energy and ejected.

Comparative Example 4 A recording medium was prepared in the same manner as in Example 1 except that the amount of silica fine particles added to the back coat layer side of the back surface was 10.0 parts. Color recording was performed by an ink jet recording apparatus in which the ink was foamed by thermal energy and ejected.

Comparative Example 5 A recording medium was prepared in the same manner as in Example 1 except that the coating liquid applied to the back coat layer side of the back surface was replaced with that used in Example 5. Color recording was carried out by an inkjet recording device which was prepared and foamed by thermal energy to eject the ink.

Comparative Example 6 A recording medium was prepared in the same manner as in Example 3 except that the coating solution applied to the back coat layer side on the back surface was replaced with that used in Comparative Example 1. Color recording was carried out by an inkjet recording device which was prepared and foamed by thermal energy to eject the ink.

Comparative Example 7 A recording medium was prepared in the same manner as in Example 1 except that nothing was coated on the back coat layer side of the back surface of Example 1, and the ink was foamed by thermal energy. Color recording was performed by an inkjet recording device that ejects ink by means of ink.

Comparative Example 8 A recording medium was prepared in the same manner as in Example 3 except that nothing was applied to the back coat layer side of the back surface of Example 3, and the ink was foamed by thermal energy. Color recording was performed by an inkjet recording device that ejects ink by means of ink.

[Evaluation Items] (1) Smoothness of the front and back surfaces of the recording medium A Beck smoothness meter measures 10 points on each of the front and back surfaces of the recording medium and outputs an average value. (2) Presence / absence of pickup roller trace-1 ASF conveyance was performed, and it was visually evaluated whether the conveyed recording medium had a pickup roller trace. Blue 60% duty printing was performed. The one with a clearly marked pickup roller mark is ×,
Those not attached, those having no effect on the image were evaluated as ◯, and those other than that were evaluated as Δ. (3) Presence / absence of pickup roller trace-2 ASF transport was performed, and the presence / absence of scratches on the recording medium under the transported recording medium was visually evaluated. Those with obvious scratches were marked with X, those without scratches, those that did not affect the image were marked with O, and those other than that were marked with Δ. (4) Conveyability The presence or absence of double feeding and slippage of the recording medium was evaluated. When there were more than 5 out of 50 times of double feeding and slip, x was given, when there was no double feeding, it was given as o, and other than that was given as Δ. (5) Print Quality 100% solid green was printed, and the degree of unevenness in the solid print portion was evaluated. When there was unevenness on the solid surface, it was marked with X, when there was no unevenness, it was marked with ◯, and when it was not, it was marked with Δ.

The evaluation results are summarized in Table 1.

[0095]

[Table 1]

[0096]

As described above, according to the present invention,
It is possible to obtain a recording medium suitable for the ASF transport system and for the inkjet recording system, and it is possible to provide a recording medium free from uneven transport such as double feeding and slip even in other normal transport systems.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a head portion of an inkjet recording apparatus used in the present invention.

FIG. 2 is a cross-sectional view of a head portion of an inkjet recording device used in the present invention.

FIG. 3 is an external perspective view of a head in which the heads shown in FIGS. 1 and 2 are multi-headed.

FIG. 4 is a perspective view showing an example of an inkjet recording apparatus.

Claims (18)

[Claims] 1. A substrate having an ink receiving layer on at least one surface thereof, and having a Bekk smoothness of 5 seconds or more and 800 seconds or less on both front and back surfaces, and a difference in smoothness of the front and back surfaces of 0 seconds or more and 280 seconds or less. A recording medium characterized by being. 2. The Bekk smoothness of both front and back surfaces is 5 seconds or more 50.
The recording medium according to claim 1, which is 0 seconds or less. 3. Bekk smoothness of 5 seconds or more on both front and back sides 30
The recording medium according to claim 1, which is 0 seconds or less. 4. An ink receiving layer is provided on one surface of a substrate,
The recording medium according to claim 1, which has a back coat layer on the opposite surface. 5. The recording medium according to claim 1, wherein the substrate has gloss. 6. The recording medium according to claim 1, wherein the substrate is a film. 7. An ink jet recording method, wherein ink is ejected onto the recording medium according to claim 1 from an orifice of a recording head according to a recording signal. 8. The ink jet recording method according to claim 7, wherein the liquid medium component of the ink is composed mainly of water and water-miscible glycols or glycol ethers. 9. The ink jet recording method according to claim 7, wherein the ink is cyan, magenta, yellow or black ink. 10. The surface tension of black ink is cyan,
The inkjet recording method according to claim 9, wherein the surface tension is higher than that of magenta and yellow inks. 11. The surface tension of black ink is 40-5.
The inkjet recording method according to claim 10, wherein the surface tension of the cyan, magenta, and yellow inks is in the range of 5 dyne / cm, and the surface tension of the cyan, magenta, and yellow inks is in the range of 30 to 40 dyne / cm. 12. The ink jet recording method according to claim 7, wherein the ink is ejected by thermal energy. 13. An image forming method, wherein an image is formed on the recording medium according to claim 1 by ejecting ink from an orifice of a recording head according to a recording signal. 14. The image forming method according to claim 13, wherein the liquid medium component of the ink is mainly composed of water and water-miscible glycols or glycol ethers. 15. The ink is cyan, magenta or yellow.
The image forming method according to claim 13, wherein the image forming method is black ink. 16. The surface tension of black ink is cyan,
The image forming method according to claim 15, wherein the surface tension is higher than those of magenta and yellow inks. 17. The surface tension of the black ink is 40-5.
The image forming method according to claim 16, wherein the surface tension of the cyan, magenta, and yellow inks is in the range of 5 dyne / cm and the range of 30 to 40 dyne / cm. 18. The image forming method according to claim 13, wherein the ink is ejected by thermal energy.