JP2002019096A - Ink-jet recording method, recording device, water-based ink used for the method or device, and member to be recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording method capable of easily erasing the image from a member to be recorded with an image formed by an ink-jet recording method or a recording device, in particular, an image formed on a plain paper so as to allow repeated use of the member to be recorded, a recording device, a water-based ink used for the recording method or the recording device, and a member to be recorded. SOLUTION: An ink-jet recording method for recording by ejecting a water- based ink onto a member to be recorded, comprising the steps of forming an image on the member to be recorded using the water-based ink made of a coloring agent contained only in a resin emulsion, erasing the image by applying the mechanical shearing force to the image, and reusing the member to be recorded, a recording device, and a water-based ink used for the recording method or the recording device, and a member to be recorded, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method, a recording apparatus, a water-based ink and a recording material used in the method or the apparatus, and more particularly, to an ink jet recording method or a recording apparatus (hereinafter referred to as a recording method). Recording material on which an image is formed, in particular,
TECHNICAL FIELD The present invention relates to an ink jet recording method and a recording apparatus which can easily erase an image formed on plain paper and perform recording using a recording material repeatedly, a water-based ink and a recording material used in this recording method.

[0002]

2. Description of the Related Art An ink jet recording method for recording an image by ejecting a liquid ink from a nozzle is capable of printing on plain paper, easily supporting colorization,
In recent years, it has been rapidly spreading as a printer for outputting documents and images created by a computer due to noise at the time of driving and low power consumption. On the other hand, paper used as a recording material in the ink jet recording method is usually made of pulp obtained from wood, and mass consumption of paper leads to environmental destruction. desired.

Conventionally, aqueous inks containing water have been used in general ink jet printers. In order to regenerate the recording material printed with the aqueous ink, it is common to collect the recording material that is no longer needed and once beating it to the pulp state or re-melting it to reuse it It is a target. However, this method has the disadvantage that the energy efficiency for regeneration is low and the regenerated product is more expensive than using new raw materials.

As a method for solving this drawback, there has been proposed a method of reusing a recorded matter using a recording liquid containing a dye which is decolored by near infrared rays (Japanese Patent Laid-Open No. 05-016).
342). However, since the dye used in this method is light blue, it is not suitable for documents generally prepared in an office using an inkjet printer. In addition, since the vehicle component remains in the image forming area of the recording material even after the erasing, the erasing part of the recording material turns yellow and cannot be used for highly confidential documents. It is thought that it will come.

In the field of ink jet printers other than water-based ink, a method is disclosed in which an image is formed by a hot-melt type ink jet printer, the recording paper is impregnated with a release liquid, and then the image on the recording material is released. (JP-A-07-133451). In this case, since the adhesion between the hot melt ink and the recording paper is strong, a sufficient amount of a peeling liquid and a large amount of energy are required to peel such an image. Further, a room temperature solid-type recording heat-meltable ink that satisfies the recording property and the erasing property for any recording paper has been proposed (JP-A-06-080914). Further, the present applicant provides a medium processing apparatus for applying a pretreatment agent for improving the releasability of an image forming substance, and an image for forming an image by transferring the image forming substance to a recording material to which the pretreatment agent has been applied. An image forming system having a forming device has been proposed (Japanese Patent Laid-Open No. Hei 10-20725).

[0006] Erasable inks in fields other than ink-jet include an aqueous polymer emulsion in which a polymer having a glass transition temperature of 30 ° C or more is dispersed in water with a particle size of 1 µm or less, and a surface tension of 55 dyne / cm
The aqueous decoloring ink described above is disclosed (Japanese Patent Publication No.
8-19357). It is said that the composition drawn on cloth or paper using this ink can be erased by a physical method such as brushing or washing. However, although this ink is suitable for the purpose of erasing the composition drawn on the cloth at the time of sewing or the like, it is a light-colored ink due to the structure of the ink, and is applicable to a full-color ink. Or the thought is not included. Further, since the surface tension of the ink was high, the permeability to plain paper was poor, and the dryness of the printed matter was poor.

[0007] In the field of inks for ink jet printers, several inks containing a resin emulsion have been disclosed, but all of them are capable of preventing image bleeding and color bleeding, and imparting water resistance, light resistance and fixability. A resin emulsion or ink having characteristics suitable for the purpose of the above, wherein the resin emulsion has characteristics suitable for the purpose of easily erasing an ink jet recorded image, an ink containing this resin emulsion, and a method for erasing an ink jet recorded image using the same Was not a suggestion.

The present applicant has proposed an ink containing a resin emulsion suitable for reuse of a recording material in ink jet recording using a resin emulsion ink, and a method of erasing an ink jet recorded image using the same. (Japanese Patent Application No. 11-109845, Japanese Patent Application No. 11-1631)
95) In addition, at present, there is a demand for a simpler method capable of reliably erasing an image by a low shear force on a recording material.

[0009]

SUMMARY OF THE INVENTION In view of the foregoing, the present invention has been made to solve the above-mentioned drawbacks and problems, and has been developed in view of a recording material on which an image is formed by an ink jet recording method, in particular, a recording material formed on plain paper. It is an object of the present invention to provide an ink jet recording method and a recording apparatus capable of easily erasing an image and using a recording material repeatedly, a water-based ink and a recording material used in this recording method.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have focused on a resin emulsion contained in an aqueous ink and a means for erasing an image and the like. Using an aqueous ink composed of a colorant (hereinafter, sometimes referred to as a colored resin emulsion) contained only in the ink, applying a mechanical shearing force to the formed image, and including a specific resin emulsion in the aqueous ink. And by using a recording material having a specific porous surface, a recording material on which an image is formed by an ink jet recording method, in particular, an image formed on plain paper can be easily erased, and a recording material that is repeated It can be used as an ink jet recording method and recording apparatus, an aqueous ink and a recording material used in this recording method. It found that, and have completed the present invention based on this finding.

That is, according to the present invention, first, in an ink jet recording method for performing recording by discharging a water-based ink onto a recording material, a water-based ink comprising a coloring agent contained only in a resin emulsion is used. An ink jet recording method is provided in which after forming an image on a recording material, the image is erased by applying a mechanical shearing force to the image, and the recording material is reused for recording. In the first invention, the recording material on which the image is recorded is conveyed, and the image is erased by bringing a roller having a spiral projection made of an elastic material into contact with the recording material. And a roller which is driven and conveyed at relatively different linear velocities to apply a mechanical shearing force.

According to the present invention, secondly, in an ink jet recording apparatus for performing recording by discharging a water-based ink onto a recording material, recording is performed using a water-based ink comprising a colorant contained only in a resin emulsion. An ink jet recording apparatus, comprising: means for forming an image on a material, means for erasing the image by applying a mechanical shearing force to the image, and means for reusing the recording material from which the image has been erased. Is done. In the second invention, the means for conveying the recording material on which the image is recorded and the erasing of the image are performed by bringing a roller having a spiral projection made of an elastic material into contact with the recording material. And an ink jet recording apparatus having means for applying a mechanical shear force by driving and conveying the roller and the roller at relatively different linear speeds.

According to the present invention, thirdly, the resin forming the resin emulsion contained in the aqueous ink has a temperature of 25 ° C.
A water-based ink having the above glass transition temperature (Tg) for use in the above-described inkjet recording method or inkjet recording apparatus is provided.

According to the present invention, fourthly, 50 to 600 n
The aqueous ink used in the inkjet recording method or the inkjet recording apparatus, wherein 99% or more by weight of the resin emulsion particles contained in the aqueous ink having a particle diameter of m are contained in the aqueous ink. Is done.

According to the present invention, fifthly, the average particle size of the resin emulsion particles contained in the aqueous ink is 50 to 50%.
A water-based ink having a thickness of 500 nm, which is used in the ink jet recording method or the ink jet recording apparatus, is provided.

According to the present invention, sixthly, there is provided an aqueous ink used in the above ink jet recording method or the ink jet recording apparatus, wherein the resin emulsion particles contained in the aqueous ink are substantially spherical. These inventions include aqueous inks having a viscosity at 25 ° C. of 8 mPa · s or less and a surface tension of 45 dyne / cm or less.

According to the present invention, seventhly, C.I. S. F20
A recording material used in the inkjet recording method or the inkjet recording apparatus, wherein the recording material is formed from pulp fibers of 0 ml or less and has a porous surface smaller in diameter than the colorant in the aqueous ink. .

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording method and a recording apparatus according to the present invention will be described. The ink jet recording will be described later, and first, after printing an ink, erasing the image will be described.

FIG. 1 is a schematic diagram showing an example of an image erasing device unit. In FIG. 1, a recording material 100 on which an image 103 is formed is a pair of guide plates 105a and 105b,
Image forming substance removing roller 1 provided with a spiral projection by recording material transport roller pair 104a, 104b
01 and the pressure roller 102. As shown in FIG. 2, the image forming substance removing roller 101 having a spiral projection has a spiral structure at a portion that comes into contact with the recording material, but the projection portion that comes into contact with the recording material is made of an elastic member. Is done. One method for producing such rollers is aluminum,
Metals such as iron and stainless steel, phenolic resin, polystyrene, ABS resin, polyester, polyamide,
A method in which an elastic member is formed into a roll shape by a known method on a core material 11 made of a synthetic polymer compound such as polyacetal or the like, and then cut into a spiral shape is used. As another method, there is a method of winding a band-shaped elastic member around the core material.

FIG. 3 is a schematic diagram in which an image is peeled from a recording member that has passed between an image forming substance removing roller and a pressure roller. Pressure is applied between the image forming substance removing roller 101 and the pressure roller 102 by a helical spring, a leaf spring (not shown), or the like. The pressure roller may be a roller provided with a rubber member such as natural rubber, urethane rubber, silicon rubber, or fluoro rubber on the surface, but it is not particularly necessary to provide an elastic body on the surface. , A metal such as stainless steel, a phenolic resin, a polystyrene, an ABS resin, a polyester, a polyamide, a synthetic polymer compound such as polyacetal. The force applied between the image forming substance removing roller 101 and the pressure roller 102 is preferably 30 to 100 gf / cm per unit length of the roller.

The appropriate value of the pressure applied between these rollers varies depending on factors such as the diameter and material of the rollers, the contact area between the spiral roller and the recording material, and the like. The removed image forming substance 108 is stored in the image forming substance collection container 10.
7 and discarded as appropriate.

In the method of removing an image with a blade member called a blade, a shearing force is applied to the image at the edge of the blade to remove the image from the recording material. Further, in the method of removing an image with a roller having an elastic body, the image is removed by applying a shearing force to the image over the entire surface where the recording material and the projection are in contact with each other rather than the edge. Therefore, when the blade is removed with a blade member, the image removal characteristics are significantly reduced due to the abrasion of the edge. On the other hand, in the case of a roller made of a spiral elastic member, it is better to slightly wear the roller itself. Is good.

In order to remove the image-forming substance, a roller having a projection provided in a spiral shape is used instead of pressing the blade over the entire width of the recording material. Can be prevented. That is, when the blade is pressed across the entire width of the recording material, the frictional force between the recording material and the blade becomes very large, and the surface of the recording material becomes rough or wrinkles are formed on the recording material. Problems, such as skew and non-feeding. When the protrusion is provided in a spiral shape, the frictional force can be reduced because the roller contacts only a part of the recording material in the width direction at a specific time during the image removing operation. In the case of pressing with full width, it is necessary to increase the pressure of the blade against the recording material in order to completely remove the image.

In the case where the projection is provided in a spiral shape, the image can be completely removed by rotating the roller with a weak pressure to substantially increase the number of times of contact with the recording material, and at the same time, The transportability of the recording material can be improved. In particular, the ratio between the contact width with the recording material and the effective width of the roller as viewed in a specific time, when the pressure applied between the spiral protrusion shape and the image forming material removing roller and the pressure roller is specified, is 1/3 or less. In such a case, the above effects can be obtained. However, if the ratio is too small, the roller rotates at a high speed, which causes problems such as generating noise, and the removed image forming substance is easily scattered. Therefore, the ratio is preferably set to 1/20 or more. .

FIG. 4 shows an example of an apparatus in which an ink jet recording unit 420 and an erasing unit 410 are incorporated in the same housing, and the transport path of the recording material is shared.
In this apparatus, the erasing unit 410 uses the image forming substance removing roller having the elastic member having the spiral projection shape described above. The recording unit 420 is a conventionally known inkjet recording unit. That is, the recording material is the recording material transport roller pair 42.
4 and a pair of paper discharge rollers 421 are conveyed between a platen 423 and a print head (422) in this unit. This conveyance is synchronized with the image signal. The inkjet print head 422 is configured to be shuttle-scanned in a direction perpendicular to the plane of the drawing. In addition to the scanning type, the carriage may be a so-called line head or pseudo line head having a nozzle array over the entire printing width. Recording target material 10 stored in paper feed tray 401
Reference numeral 3 denotes a sheet feeding guide 40 one by one by a sheet feeding roller 402.
3, an erasing unit 410 and an ink jet 4
20.

In the apparatus shown in FIG. 4, the same recording material may be present in the erasing unit 410 and the ink jet 420 at the same time, and the conveying speed of the recording material is changed between the erasing unit 410 and the ink jet recording unit 420. It is difficult. Accordingly, if the erasing unit 410 and the ink jet recording unit 420 are operated at the same time with the same conveyance speed of the recording material, the portion where there is no image, which is performed by a normal ink jet recording apparatus, is step-conveyed. Cannot operate. Therefore, the erasing unit 410 and the ink jet recording unit 420
If both are operated at the same time, the recording speed of the image is reduced. That is, when reproducing a used recording material that has been used and becomes unnecessary, the erasing unit 410 is used.
When the image recording is performed by using only the ink-jet recording unit 420, the recording medium having no image recorded thereon is mounted on the sheet feeding tray 401, and only the inkjet recording unit 420 is operated. Preferably.

The aqueous ink used in such an ink jet recording method and recording apparatus will be described below. Usually, the aqueous ink is composed of a coloring agent composed of a dye or a pigment, and a vehicle such as a wetting agent and a penetrant solvent.
However, when printing on paper with such an aqueous ink, the coloring agent also penetrates and fixes in the paper fibers as the vehicle penetrates, making it very difficult to remove them. Japanese Patent Application No. 11-10984 filed by the present applicant
5. According to the erasable ink disclosed in Japanese Patent Application No. 11-163195, the vehicle in the ink penetrates the paper, but the resin emulsion colored with a colorant forms a film on the surface of the paper. It does not enter deeply between the holes of the paper, but is distributed only on the surface. As described above, the coating containing the colorant formed on the paper surface can be easily removed by applying a mechanical shearing force using a metal or resin blade or the like, and the transfer member can be removed by the coating forming portion. Then, the recording material can be peeled off from the recording material by being pressed and transferred. However, when an image formed by using the above ink is overlaid and stored, an adverse effect such as a part of the image adhering to another recording material may occur.

As a result of further studies, the present inventors have found that an ink-jet recording is carried out using an aqueous ink containing a resin emulsion containing a colorant having a specific glass transition temperature (Tg) and a specific particle size. The image formed on the recording material by the method does not adhere to another recording material even when it is stored in an overlapping manner, and when recording on plain paper, it does not form a coating. However, it has been found that the toner exhibits satisfactory fixing properties in practical use, and that the image can be easily erased by applying a mechanical shearing force with an elastic member.

The aqueous ink of the present invention has a viscosity at 25 ° C. of 8 mPa · s or less and a surface tension of 45 dy.
It is preferably not more than ne / cm. If the viscosity of the ink exceeds 8 mPa · s, clogging of the head occurs and stable ejection cannot be performed. Surface tension is 4
If it is higher than 5 dyne / cm, the permeability to a recording material such as plain paper will be poor, and the drying property of the image will be poor or bleeding will occur. Further, this aqueous ink has a porous layer having a smaller diameter than the colored fine particles in the ink-jet ink. S. It has been found that the erasability of the image is further improved by using it in combination with a recording material made of pulp fiber of F 200 ml or less.

As the colored resin emulsion used in the aqueous ink of the present invention, those having a resin component having a Tg equal to or higher than the image fixing temperature are used. When Tg is lower than this temperature, a problem may occur in the storability of an image.
As such a resin, a vinyl resin is preferable.
For example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-phenylstyrene,
p-ethylstyrene, 2,4-dimethylstyrene, p-
n-butylstyrene, p-tert-butylstyrene,
p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-chlorostyrene, 3,4-di Chlorostyrene,
styrene derivatives such as m-nitrostyrene, o-nitrostyrene and p-nitrostyrene, and ethylene and unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; unsaturated diolefins such as butadiene and isoprene; vinyl chloride Vinyl halides such as vinylidene chloride, vinyl bromide and vinyl fluoride; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; methacrylic acid and methyl methacrylate;
Α-methylene aliphatic monomers such as ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate and phenyl methacrylate Carboxylic esters; acrylic acid and methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, Acrylates such as 2-chloroethyl acrylate and phenyl acrylate;
Maleic acid, maleic acid half ester; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl carbazole N-vinyl compounds such as N-vinylindole and N-vinylpyrrolidone; vinylnaphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide; one or more acroleins selected and used A polymerized product is used.

In producing the above polymer used in the present invention, a crosslinked polymer can be obtained by using a crosslinking agent. As the crosslinking agent in this case, a general crosslinking agent can be appropriately used, and specific examples thereof include divinylbenzene, divinylnaphthalene, divinylether, divinylsulfone, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, ethylene glycol dimethacrylate, and ethylene glycol dimethacrylate. Polyethylene glycol dimethacrylate, diethylene glycol diacrylate,
Triethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate,
2,2'-bis (4-methacryloxydiethoxyphenyl) propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetra Acrylate,
Dibromoneopentyl glycol dimethacrylate, allyl phthalate, 1,2-propylene glycol, 1,3
-Butanediol and the like.

In order to obtain a colored resin emulsion composed of these resins, a method of melt-kneading a colorant and the above resin, finely pulverizing them and dispersing them in water, mixing the colorant with the above resin in a solvent, preparing a fine particle After dispersing in water, the method of removing the solvent, a method of mixing a colorant with a monomer that forms these resins, dispersing in water and then polymerizing, adding a colorant to a resin emulsion dispersed in water Any method such as a coloring method is adopted.

The particle size of the colored resin emulsion particles is preferably in the range of 50 to 600 nm with 99% or more particles by weight. The presence of emulsion particles exceeding 600 nm makes it difficult to form normal ink droplets with an inkjet nozzle or causes clogging of the nozzle. Particles having a particle diameter of less than 50 nm tend to easily penetrate into the paper together with the vehicle, and may remain during erasing. When the particle diameter of the colored resin emulsion has a distribution, the average particle diameter is 50 to 500.
The thickness is preferably about nm, and is appropriately adjusted so as to fall within the range.

The colored resin emulsion preferably has a substantially spherical shape. Such particles are obtained by granulation in a liquid, and can be easily produced by a suspension polymerization method or an emulsion polymerization method. If the shape is irregular and you try to erase the image with mechanical shear,
It is easily entangled with the fibers of the recording material, and the erasability is reduced.

In the measurement of the particle size distribution in the present invention,
A dynamic light scattering method (Doppler scattered light analysis) is used to irradiate laser light to particles in the ink that are performing Brownian motion, and to determine the particle diameter from the amount of frequency change of light (backscattered light) returning from the particles. Further, the average particle size refers to a particle size of 50% by volume cumulative percentage.

The content of the colored resin emulsion in the aqueous ink is 1 to 50% by weight, preferably 3 to 50%.
３０30%. If the content is less than 1%, the density of the image is not sufficient, and if it exceeds 50%, the viscosity of the ink is remarkably increased, which causes a problem in ejection stability, which is not desirable.

As the colorant in the present invention, a pigment or a dye is used. Examples of the pigment include azo, phthalocyanine, anthraquinone, dioxazine, indigo, thioindigo, perylene, isoindolenone, aniline black, azomethine, rhodamine B lake pigments, carbon black, etc. Examples of the inorganic pigment include iron oxide, titanium oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, dark blue, cadmium red, chrome yellow, and metal powder.

Of these, furnace black and black ink are particularly preferable for forming a color image.
Examples include carbon blacks such as acetylene black, channel black, and lamp black; organic pigments such as aniline black; and metals such as copper oxide, titanium oxide, and iron oxide. In the yellow ink, an azo-based C.I. I. Pigment Yellow 1,3,12,13,14,17,2
4,34,35,37,42,53,55,81,8
3,95,97,98,100,101,104,10
8, 109, 110, 117, 120, 138, 15
Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 4 in Magenta Ink.
8: 2,48: 2,48: 3,48: 4,49: 1,5
2: 2, 53: 1, 57: 1, 60: 1, 63: 1, 6
3: 2, 64: 1, 81, 83, 88, 101, 10
4,105,106,108,112,114,12
2,123,146,149,166,168,17
0,172,177,178,179,185,19
0, 193, 209 and 219, and C.I. I. Pigment Blue 1,2,15,15: 1,1
5: 2, 15: 3, 15: 4, 15: 6, 16, 17:
1, 56, 60, 63, copper phthalocyanine, metal-free phthalocyanine, and the like.

The dyes used in the present invention include direct dyes, acid dyes, basic dyes, disperse dyes, oil-soluble dyes, reactive dyes, fluorescent dyes and the like. Specifically, C.I. l.
Acid Yellow 17, 19, 23, 25, 39, 4
0, 42, 44, 49, 50, 61, 64, 76, 7
9, 142, C.I. l. Acid Red 1, 8, 13,
14, 18, 26, 27, 35, 37, 42, 52, 8
2,87,89,92,97,106,111,11
4,115,134,186,249,254,28
9, C.I. l. Acid Blue 9, 29, 45, 92,
249, C.I. l. Acid Black 1, 2, 7, 24,
26, 94, C.I. l. Food Yellow 3, 4, C.I.
l. Food red 7, 9, 14, C.I. l. Food Black 1, 2, C.I. l. Direct yellow l, l
2,24,26,33,44,50,86,120,1
32, 142, 144, 157, C.I. l. direct·
Red 1,4,9,13,17,20,28,31,3
9, 80, 81, 83, 89, 225, 227;
l. Direct orange 26, 29, 62, 102,
C. l. Direct Blue 1,2,6,15,22,
25, 71, 76, 79, 86, 87, 90, 98, 1
63, 165, 199, 202, C.I. l. direct·
Black 19,22,32,38,51,56,71,
74, 75, 77, 154, 168, 171; l.
Basic Yellow 1,2,11,13,14,1
5,19,21,23,24,25,28,29,3
2,36,40,41,45,49,51,53,6
3, 67, 70, 73, 77, 87, 91, C.I. l. Basic Red 2,12,13,14,15,18,
22, 23, 24, 27, 29, 35, 36, 38, 3
9, 46, 49, 51, 52, 54, 59, 68, 6
9, 70, 73, 78, 82, 102, 104, 10
9, 112, C.I. l. Basic Blue 1,3,5
7, 9, 21, 22, 26, 35, 41, 45, 47,
54, 62, 65, 66, 67, 69, 75, 77, 7
8,89,92,93,105,117,120,12
2,124,129,137,141,147,15
5, C.I. l. Basic Black 2, 8, C.I. l. Reactive Yellow 1, 5, 11, 13, 14, 2
0, 21, 22, 25, 40, 47, 51, 55, 6
5,67, C.I. l. Reactive Red 1,14,1
7, 25, 26, 32, 37, 44, 46, 55, 6
0, 66, 74, 79, 96, 97, 180, C.I. l.
Reactive Blue 1,2,7,14,15,23,
32, 35, 38, 41, 63, 80, 95, C.I. l.
Reactive Black 3,4,7,11,12,1
7, nigrosine, C.I. I. Solvent Black 3, 5,
7, 22, 23, C.I. I. Solvent Yellow 2, 6,
14, 15, 19, 21, 61, 80, C.I. I. Solvent Red 3, 8, 24, 25, 49, 81, 82, 8
3, 84, 109, 121, C.I. I. Solvent Blue 11, 12, 25, 35, 36, 55, 73, etc., and these can be used alone or in combination of two or more. The content of these colorants in the emulsion is 1 to 90% by weight, preferably 10 to 50%.
It is.

To form the colored resin emulsion used in the present invention, a surfactant is used. Examples of the surfactant include sorbitan fatty acid ester, glycerin fatty acid ester, decaglycerin fatty acid ester, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbit fatty acid ester, polyoxyethylene glycerin fatty acid ester, and polyethylene glycol fatty acid ester , Polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene castor oil, polyoxyethylene lanolin, lanolin, alcohol, beeswax derivatives, polyoxyethylene alkylamine, fatty acid amide, etc. Nonionic surfactants, alkyl sulfates, polyoxyethylene alkyl ether sulfates N- acylamino acid salt, N- acyl methyl taurate, polyoxyethylene alkyl ether acetate, alpha-
Anionic surfactants such as olefin sulfonates, alkyl phosphates, and polyoxyethylene alkyl ether phosphates are included.

In addition to the above components, the water-based ink of the present invention may contain various water-soluble additives which are usually used in ink-jet recording inks, for example, as a wetting agent and as a dissolution stabilizer for the ink components. Organic solvents can be used. For example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polyhydric alcohols such as glycerol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, Polyhydric alcohol alkyl ethers such as tetraethylene glycol monomethyl ether and propylene glycol monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; N-methyl-2-virolidone; -Hydroxyethyl-2-pyrrolidone, l, 3- Amides methyl imino Ida oxazolidinone, .epsilon. Kaburorakutamu, nitrogen-containing heterocyclic compounds such as γ- butyrolactone, formamide, N- methylformamide, N, etc. N- dimethylformamide,
Amines such as monoethanolamine, diethanolamine, triethanolamine, monoethylamine, diethylamine and triethylamine, dimethyl sulfoxide,
Examples thereof include sulfur-containing compounds such as sulfolane and thiodiethanol, propylene carbonate, ethylene carbonate and the like, which are used alone or in combination. The content of these water-soluble organic solvents in the ink is from 1 to 40 on a weight basis.
%, Preferably 5 to 20%.

For adjusting the surface tension, various penetrants can be used. Specifically, alkyl and aryl ethers of polyhydric alcohols such as ethylene glycol monophenyl ether, diethylene glycol monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, and tetraethylene glycol chlorophenyl ether; Examples include surfactants, lower alcohols such as ethanol and 2-propanol, and these are used alone or in combination of two or more. The content of these penetrants in the ink is 0.3 to 5% by weight, preferably 0.5 to 2%. Further, if necessary, other known preservatives, fungicides, ultraviolet absorbers, light stabilizers, pH adjusters, and rust inhibitors may be used. Usually, the colorant is present in the ink in a dissolved state (for a dye) or a dispersed state (for a pigment). When the ink contains a resin emulsion, the colorant is contained in components other than the resin emulsion. In the present invention, the colorant is present only in the resin emulsion, and the other components are free of the colorant, thereby improving the erasability of the image.

The present invention further provides C.I. S. A recording material for use in the ink jet recording method or the ink jet recording apparatus, characterized by having a porous surface formed of pulp fibers having a F of 200 ml or less and having a diameter smaller than that of the colorant in the aqueous ink. The base paper of the recording material can be manufactured by forming a papermaking raw material mainly composed of pulp fiber and filler by a conventional method. As the pulp, any pulp can be used without particular limitation as long as it is used for ordinary paper production. For example, one kind or a mixture of chemical pulp such as LBKP and NBKP, mechanical pulp, recycled pulp, non-wood pulp and the like is used. be able to. In the recording material of the present invention, the pulp fiber is C.I. S. F. It is beaten to 200 ml or less, and a filler, a sizing agent, a papermaking aid, and the like are blended as necessary, and the paper can be obtained. As a filler,
For example, calcium carbonate, kaolin, talc, titanium dioxide and the like can be mentioned. Examples of the sizing agent include rosin size, alkyl ketene dimer, alkenyl succinic anhydride, petroleum resin size, epichlorohydrin, acrylamide and the like. C. S. F is 0.3
The amount of water flowing out when 1000% of the stock having a concentration of 1000% was dropped from a container having a pore at the bottom into a receiver, and indicates the degree of beating. In the present invention, pulp fibers are C.I. S. By beating to F 200 ml or less, the erasability of the image can be improved, and if it exceeds 200 ml, the erasability of the image will be reduced.

[0044]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. The terms “parts” and “%” are based on weight unless otherwise specified.

[Preparation of Colored Resin Emulsion] <Colored Resin Emulsion 1> 30 parts of carbon black REAGAL300 (manufactured by Cabot) 70 parts of styrene-butyl acrylate copolymer (Tg = 65 ° C.) 70 parts After mixing, the mixture was melt-kneaded by a three-roll mill, cooled, and coarsely ground to a particle size of about 2 mm using a hammer mill. Next, a particle size of about 7μ was obtained using a pulverizer using an air jet method.
m. Subsequently, 20 parts of the above finely pulverized product, 75 parts of water, and 5 parts of ammonium polyoxyethylene alkylphenyl sulfate were pulverized for 10 hours while cooling with a sand mill to prepare a dispersion. Further, this dispersion was kept at 80 ° C. for 1 hour and subjected to spheroidizing treatment. The coarse particles were removed by centrifugation to obtain a colored resin emulsion 1 having an average particle diameter of 105 nm.

<Colored Resin Emulsion 2> Carbon black MA-100 (manufactured by Mitsubishi Kasei Co., Ltd.) 50 parts Styrene-butyl methacrylate copolymer (Tg = 75 ° C.) 50 parts Xylene 300 parts was sufficiently mixed and dissolved. Next, the above solution was mixed in an aqueous medium containing 600 parts of water, 5 parts of polyvinyl alcohol, and 1 part of sodium dodecylbenzenesulfonate, and stirred with a TK homomixer to be dispersed to an average particle diameter of 120 nm. The xylene was removed under reduced pressure, and coarse particles were removed by centrifugation to obtain a colored resin emulsion 2.

<Colored resin emulsion 3> Carbon black MA-100 (manufactured by Mitsubishi Chemical Corporation) 20 parts Styrene 70 parts Butyl methacrylate 25 parts Divinylbenzene 5 parts Azobisisobutyronitrile (AIBN) 3 parts Water 300 parts Polyvinyl alcohol 3 parts sodium dodecylbenzenesulfonate 1 part The above material was stirred with a TK homomixer to give an average particle size of 7
Dispersed at 0 nm. This composition is heated to 70 ° C. in a nitrogen atmosphere.
For 5 hours, and coarse particles were removed by centrifugation to obtain a colored resin emulsion 3.

<Colored resin emulsion 4> TONERMAGENTE-02 (manufactured by Clariant) 20 parts Styrene 65 parts Butyl methacrylate 30 parts 2-ethylhexyl methacrylate 5 parts Azobisisobutyronitrile (AIBN) 3 parts Water 300 parts polyvinyl alcohol 3 parts sodium dodecylbenzenesulfonate 1 part The above material was stirred with a TK homomixer to give an average particle size of 7
Dispersed at 0 nm. This composition is heated to 70 ° C. in a nitrogen atmosphere.
For 5 hours, and coarse particles were removed by centrifugation to obtain a colored resin emulsion 4.

<Colored resin emulsion 5> 69 parts of styrene 20 parts of butyl methacrylate 20 parts 2-ethylhexyl methacrylate 10 parts 1 part of sodium styrenesulfonate 1 part of potassium persulfate 1 part of water 300 parts Polymerized. Next, a black disperse dye (Disperse Diazo B)
Lack B) 10 g was added, and the mixture was charged into an autoclave and dyed at 120 ° C. for 2 hours to give a colored resin emulsion 5
I got

<Colored resin emulsion 6> Carbon black MA-100 (manufactured by Mitsubishi Kasei Corporation) 20 parts Styrene 35 parts Butyl methacrylate 20 parts 2-ethylhexyl methacrylate 15 parts Azobisisobutyronitrile (AIBN) 3 parts Water 300 Part Polyvinyl alcohol 3 parts Sodium dodecylbenzenesulfonate 1 part The above material was stirred with a TK homomixer to give an average particle size of 7
Dispersed at 0 nm. This composition is heated to 70 ° C. in a nitrogen atmosphere.
For 5 hours, and coarse particles were removed by centrifugation to obtain a colored resin emulsion 6.

<Colored resin emulsion 7> Carbon black MA-100 (manufactured by Mitsubishi Kasei Co., Ltd.) 20 parts Styrene 70 parts Butyl methacrylate 20 parts 2-ethylhexyl methacrylate 5 parts Divinylbenzene 5 parts Azobisisobutyronitrile (AIBN) 3 parts Water 300 parts Polyvinyl alcohol 3 parts Sodium dodecylbenzenesulfonate 0.5 part The above materials were dispersed by stirring with a TK homomixer. This composition was polymerized at 70 ° C. for 5 hours under a nitrogen atmosphere, and coarse particles were removed by centrifugation to obtain a colored resin emulsion 7 having an average particle diameter of 550 nm.

<Colored Resin Emulsion 8> A colored resin emulsion 8 having an average particle diameter of 105 nm was obtained in the same manner as in the colored resin emulsion 1, except that the sphering treatment at 80 ° C. was not performed.

The particle diameter and T of the above colored resin emulsion
g is shown in Table 1.

[Table 1]

[Preparation of Recording Material] LBKP as pulp
And NBKP were mixed at a mixing ratio of 9: 1. S. F was adjusted to 150 ml. Next, sodium carbonate, an alkyl ketene dimer sizing agent and calcium carbonate were added to prepare a stock. This stock was made with a fourdrinier using a 70-mesh wire under the conditions of ordinary neutral paper, and starch and sodium chloride were size-pressed. A recording material having a basis weight of 64 g / m ² and a density of 0.7 g / cm ³ was obtained.

[Preparation of Ink] <Aqueous Inks 1 to 8> The above colored resin emulsions 1 to 8
And colored emulsion inks 1 to 8 were prepared according to the following formulations. However, the prepared emulsion was lightly settled by a centrifugal separator, and the operation of redispersion with ion-exchanged water was repeated to remove the excess dispersant and to adjust the solid content concentration before use. The particle diameter of the colored resin emulsion did not change even after the preparation of the ink.
% Was confirmed to be distributed.

Colored resin emulsion (solid content) 8% glycerin 3% diethylene glycol 12% 2-pyrrolidone 2% ECTD-3NEX 0.1% (anionic surfactant manufactured by Nikko Chemicals) Proxel XL (manufactured by ICI) 0.4% ion-exchanged water remaining amount An ink composition having the above formulation was prepared, and adjusted with a 10% aqueous solution of lithium hydroxide so that the pH became 10, and used. In addition, the viscosity at 25 ° C. of all inks is 2 to 3 mp · s, and the surface tension is 25 to 35 dyne /
cm.

<Aqueous ink 9> Colored resin emulsion 5 (solid content) 40% Glycerin 3% Diethylene glycol 12% 2-Pyrrolidone 2% Proxel XL (manufactured by ICI) 0.4% Ion-exchanged water Remaining amount The above formulation In the same manner as in inks 1 to 8, Ink 9 was prepared. The viscosity of this ink at 25 ° C is 23 mp
s, the surface tension was 47 dyne / cm.

<Aqueous ink 10> Carbon black MA-100 (manufactured by Mitsubishi Kasei Corporation) 5% Polyoxyethylene alkylphenyl ammonium sulfate 2% Glycerin 3% Diethylene glycol 12% 2-pyrrolidone 2% ECTD-3NEX 0.1% (Nikko Chemicals anionic surfactant) Proxel XL (manufactured by ICI) 0.4% ion-exchanged water remaining amount Prepare an ink composition having the above formulation, and prepare a 10% aqueous solution of lithium hydroxide so that the pH becomes 10. Was adjusted. Thereafter, the mixture was filtered through a membrane filter having an average pore diameter of 0.8 μm to obtain a general pigment ink 10. 2 of this ink
The viscosity at 5 ° C. is 2.6 mp · s, and the surface tension is 33 d.
yne / cm.

[Evaluation] An on-demand type ink jet printer using a piezoelectric element (IPSi, manufactured by Ricoh)
Using O Jet 300), the head was filled with the above ink, and printing was performed at room temperature (18 ° C.). The quality of an image obtained by the following method, image erasability, and ejection stability of the ink were evaluated. The recording material is NBS Corporation.
Ricoh's MyPaper or the paper prepared in the above preparation example was used.

1. Image erasability A recording material on which an image was recorded by performing printing with an ink jet printer was applied to a recording material having a linear velocity of 10 using the apparatus shown in FIG.
The rotation speed of the image removing roller is adjusted to perform an image erasing operation under the condition that the spiral protrusion of the image removing roller and the recording material abut on the same portion of the recording material three times in mm / sec. Was. It was visually evaluated as follows. ◎ When the residual image on the paper was not observed and could not be distinguished from unused paper at all. ○ When the residual image on the paper is hardly observed and there is no problem in reuse. △ When the image on the paper became slightly lighter, but the paper could not be reused. × When the image did not come off at all.

[0061] 2. Image quality Printing with an inkjet printer, image bleeding,
The concentration was visually evaluated as follows. ○ Good. X: The bleeding is conspicuous and the density is low.

3. Image storability 10 sheets of recording material on which images are recorded are stacked, and 50 g / cm
^After placing the weight so that the pressure of ² was applied and leaving it at room temperature for one week, the adhesion of the ink to the back surface of another recording material in contact with the image surface was examined and evaluated as follows. ○ No ink stains. ×: Adhesion of ink was observed.

3. Discharge stability Continuous injection was performed for 10 hours at room temperature, and the evaluation was as follows.場合 When printing is possible without image distortion. × When printing is not possible.

Table 2 shows the results.

[Table 2]

[0065]

According to the present invention, a recording material on which an image is formed by an ink jet recording method or a recording apparatus, in particular, an image formed on plain paper can be easily erased, and the recording material is used repeatedly. The present invention provides an ink jet recording method and a recording apparatus, a water-based ink used for the recording method and the recording apparatus, and a recording material. More specifically, the recording material can be used repeatedly, without damaging the recording material, improving the erasability of the image, and improving the storability of the image. The ink can be stably ejected without clogging, has high permeability to a recording material and reduces image bleeding, and greatly contributes to the inkjet recording field.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of an image erasing device unit.

FIG. 2 is a schematic view showing an example of an image forming substance removing roller provided with an elastic member.

FIG. 3 is a schematic diagram illustrating a state in which an image is peeled from a recording member that has passed between an image forming substance removing roller and a pressure roller.

FIG. 4 is a diagram showing an example of an apparatus in which the erasing unit of FIG. 1 is incorporated in the same housing as the ink jet recording unit, and the transport path of the recording material is shared.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 recording material 101 image forming material removing roller 102 pressure roller 103 image 104 a recording material transporting roller 104 b recording material transporting roller 105 a guide plate 105 b guide plate 107 recovery container 108 removed image forming material 401 paper feed tray 402 feed Paper roller 403 Paper feed guide 410 Erasure unit 420 Recording unit 422 Print head 423 Platen in unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) B41J 3/04 101Y (72) Inventor Masaji Murakami 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. In Ricoh (72) Inventor Kiyofumi Nagai 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Tomoko Sekine 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Company F Term (reference) 2C056 EA19 EA24 FA02 FC01 FC06 HA27 2H086 BA02 BA05 BA21 BA41 BA53 BA59 BA60 BA61 4J039 AD01 AD03 AD05 AD06 AD08 AD10 AD11 AD12 AD23 AE03 BA04 BA13 BA35 BA37 BA39 BC05 BC07 BC14 BC15 BE01 BE02 BE03 BE04 BE05 BE07 CA03 CA06 EA28 EA29 EA48 GA24

Claims (10)

[Claims] In an ink jet recording method for performing recording by discharging an aqueous ink onto a recording material, an image is formed on the recording material using an aqueous ink composed of a coloring agent contained only in a resin emulsion. An ink-jet recording method, wherein a mechanical shearing force is applied to the image to erase the image, and the recording material is reused for recording. 2. A recording material on which an image is recorded is conveyed, and the image is erased by contacting the recording material with a roller having a spiral projection made of an elastic material. 2. The ink jet recording method according to claim 1, wherein the step (c) is performed by applying a mechanical shear force by driving and conveying at relatively different linear velocities. 3. An ink jet recording apparatus for performing recording by discharging an aqueous ink onto a recording material, means for forming an image on the recording material using an aqueous ink comprising a colorant contained only in a resin emulsion. An ink jet recording apparatus comprising: means for applying a mechanical shearing force to the image to erase the image; and means for reusing the recording material from which the image has been erased. 4. A means for transporting a recording material on which an image has been recorded and erasing the image by contacting the recording material with a roller having a spiral projection made of an elastic material. 4. The ink jet recording apparatus according to claim 3, further comprising means for applying a mechanical shearing force by driving and conveying at relatively different linear velocities. 5. The ink jet recording method according to claim 1, wherein the resin forming the resin emulsion contained in the aqueous ink has a glass transition temperature (Tg) of 25 ° C. or higher. Aqueous ink used in inkjet recording devices. 6. The water-based ink according to claim 1, wherein 99% or more by weight of the resin emulsion particles contained in the aqueous ink having a particle diameter of 50 to 600 nm are contained in the aqueous ink. Aqueous ink used in the ink jet recording method or the ink jet recording apparatus according to the above. 7. The aqueous ink used in the inkjet recording method or the inkjet recording apparatus according to claim 1, wherein the average particle size of the resin emulsion particles contained in the aqueous ink is 50 to 500 nm. 8. The aqueous ink used in the inkjet recording method or the inkjet recording apparatus according to claim 1, wherein the resin emulsion particles contained in the aqueous ink are substantially spherical. 9. The aqueous ink according to claim 5, which has a viscosity at 25 ° C. of 8 mPa · s or less and a surface tension of 45 dyne / cm or less. 10. A freeness value (C.S.
The ink-jet recording method according to any one of claims 1 to 4, wherein F) is formed from pulp fibers of 200 ml or less, and has a porous surface having a diameter smaller than that of the colorant in the aqueous ink. A recording material used in an ink jet recording apparatus.