JP3392007B2 - Image forming method - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for forming an image coated with a transparent resin layer by inkjet recording.

[0002]

2. Description of the Related Art The conventional image forming method using an ink jet method has been mainly used to form an image by forming a visible image on a recording medium using a visible material such as a dye or a pigment. However, such a method has drawbacks in that the visible material undergoes discoloration or fading due to light or ozone during storage of an image (print), and image bleeding or the like occurs due to contact with water. There is also a problem that the glossiness of the visible image cannot be sufficiently obtained. As a means for solving these problems, there is a method of forming a protective layer by coating the surface layer of the image after recording. For example, in JP-A-7-237348 and JP-A-8-2090, a latex layer is provided on an alumina hydrate layer, and an image is formed on the alumina hydrate layer by an ink, and then an upper portion thereof is formed. A method of coating the latex layer of is disclosed.

[0003]

However, when the latex layer is heated to form a film in the above-mentioned conventional method, if the ink, particularly the solvent component thereof, remains in the latex layer, the latex layer is heat treated. In some cases, the surface of the obtained coating film could not have sufficiently good smoothness, and sufficiently high glossiness could not be obtained. In addition, cracks may occur in the coating film due to the residual solvent, which may cause a problem that the water resistance and weather resistance of the portion are deteriorated.

An object of the present invention is to provide an image forming method capable of more completely forming a film by heating a latex layer and more reliably improving the glossiness, water resistance, light resistance and the like of an image. It is in.

[0005]

The image forming method of the present invention is a method for forming an image covered with a surface layer composed of a transparent resin layer by ink jet recording, comprising the steps of: (a) absorbing an ink on a water impermeable substrate; Step of supplying ink droplets from the surface layer side to a recording medium provided with an ink receiving layer having a hydrophilic lower layer and a porous surface layer containing a thermoplastic latex resin by an inkjet method according to recording information And (b) at the stage where an image is formed by the ink supplied to the surface layer of the ink receiving layer by the step (a), transmitted through the surface layer, and absorbed in the lower layer thereof, the surface layer is transparently coated. The lower layer is pigment and alumina.
Filling consisting of one or more selected from hydrates
Material and a binder, and the thickness d (μm) of the lower layer and the maximum ink recording speed v ( μl / m) during inkjet recording.
(m · sec), and d ≧ 6.0 · v.

In the above method, a water-permeable base material may be used as the base material instead of the water-impermeable base material. In this case, the relationship between d and v is d ≧ 3.0 · v. It

The method of the present invention uses a recording medium having an ink-absorbing lower layer and an ink-receiving layer having at least two layers of a porous surface layer containing a latex resin provided on the lower layer, and an ink jet system for the recording medium. The ink jet recording is performed under the condition that the recording speed by the above and the layer thickness of the lower layer constituting the ink receiving layer of the recording medium satisfy the above specific relationship, and, if necessary, the time from the end of recording to the fixing process. By ensuring the space, it is possible to perform the fixing process in a state where the ink or the ink component (particularly the solvent component of the ink) does not remain on the surface layer, and it is possible to provide a high-quality and highly weather-resistant print.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The image forming method of the present invention will be described in detail below.

The surface layer of the ink receiving layer of the recording medium used in the present invention is formed of a porous layer containing a latex resin. This porous surface layer can be formed, for example, by coating a lower layer already provided on the substrate with a solution containing latex by a conventional method and drying. The latex resin to be contained in the surface layer may be any one as long as it is ink permeable and can form a porous layer capable of being formed into a transparent film by heat treatment, for example, vinyl chloride type, vinyl chloride-vinyl acetate type, SBR. System, NB
Examples include R-based, acrylic-based, urethane-based, polyester-based, and ethylene-based latexes, and vinyl chloride-vinyl acetate-based latex resins are preferable in consideration of scratch resistance. Further, the latex resin has an average particle size (weight average) in the range of 0.2 to 5 μm, a particle size distribution width of 3σ or less, and a particle size of ⅕ or less of the average particle size. Of particles of 10% by weight or less (in solid content)
Is preferable because the pore size of the porous layer as the surface layer is appropriately increased and good ink permeability is obtained.

The thickness of the surface layer is set so that a film having a desired function can be obtained when it is formed into a transparent film after image formation. For example, the thickness can be in the range of about 1 to 20 μm, and the film property thereof is set. From the viewpoint of ink permeability, 3 to 15 μm is preferable.

The ink absorbing lower layer provided below the surface layer in the ink receiving layer is a layer on which an image is formed by holding the ink that has permeated the surface layer there, and permeates the surface layer. A function of absorbing ink more completely and at high speed is required. The lower layer having such a function is
For example, a filler having an ink absorbing capacity may be mainly used, and a binder may be used if necessary. Examples of the filler include pigments such as light calcium carbonate, aluminum hydroxide, synthetic alumina, synthetic silica, and alumina hydrate, and one or more of these may be used in combination. . It is preferable to use at least alumina hydrate in order to obtain a higher absorption and higher quality image. Examples of the binder used as necessary include polyvinyl alcohol and modified products thereof, gelatin and modified products thereof, starch and modified products thereof, and casein and modified products thereof.

The compounding ratio of the filler and the binder is a weight ratio,
It can be selected from the range of 1: 1 to 30: 1, preferably 5: 1 to 25: 1.

The layer thickness of this lower layer is, for example, 10 to 100.
μm, and from this range the above-mentioned conditions,
That is, when a water-impermeable base material such as a resin film is used as the base material, d ≧ 6.0 · v, and when a water-permeable base material such as general paper, coated paper, or baryta paper is used, d ≧ 3. 0v
The layer thickness satisfying the above conditions may be selected in consideration of the recording conditions.

As the base material of the recording medium, polyester,
Transparent films of polysulfone, polyvinyl chloride, polycarbonate, polystyrene, polymethylmethacrylate, cellulose acetate, polyethylene, polyethylene terephthalate, polypropylene, etc., films whitened by filling these transparent films with white pigment, general paper, coated paper , Baryta paper or the like is used.

The method of the present invention will now be described with reference to the drawings. FIG. 1 is an example of an image forming apparatus applicable to the present invention. This image forming apparatus has a configuration in which the recording unit 101 is provided with a recording head for performing recording by an inkjet method using inks of different colors shown in FIG. As the recording head, a bubble jet method is preferable in terms of high speed recording, but a thermal method, a piezo method,
Other methods such as a continuous method can also be used.

As the ink, for example, various inks used for ink jet can be used. Of these, water-based inks containing water-soluble dyes such as direct dyes and acid dyes are preferable.

In this recording unit 101, the transport roller 1
Recording is performed on the recording medium conveyed by 02 by applying ink droplets according to the recording information. In this recording, recording is performed by moving the recording head relative to the recording medium, and the maximum ink recording speed at that time is related to the layer thickness of the lower layer in the ink receiving layer of the recording medium. It is assumed that the conditions shown above are satisfied. Depending on the desired recording conditions, the layer thickness of the ink receiving layer lower layer may be set for the maximum ink recording speed used, or the maximum ink recording speed may be set for the layer thickness of the ink receiving layer lower layer. May be set.

The relative movement of the recording head with respect to the recording medium is, for example, as shown in FIG.
The four heads (magenta head 2, cyan head 3 and black head 4) are arranged so that the nozzle rows of the heads are parallel to each other, and these are integrated and serially scanned in the direction of arrow y in the figure. (The arrow x in the drawing indicates the upper direction, and the arrow z indicates the paper feeding direction orthogonal to the scanning direction). When printing of one line in the scan direction with a width corresponding to the length of the nozzle row in each head is completed, the paper is fed by the required width and the ink droplets of each color are sent to the specified part according to the print information. Record.

After the recording is completed, the recording medium is conveyed by rollers 104, and when it reaches the intermediate tray 103, it is conveyed obliquely downward in the figure, and a fixing process is performed by forming a transparent film on the surface layer. FIG. 3 shows an example of the fixing unit. As shown in FIGS. 2 and 3, the fixing unit is provided with a pair of heat rollers 105 and 106, and the recording medium is passed between them to fix the recording medium after the recording is completed, that is, ink reception. The surface of the layer is transparently coated. The heating at this time can be performed, for example, at a temperature selected from the minimum film-forming temperature of the latex resin contained in the surface layer or higher, depending on the material constituting the recording medium, the physical properties of the ink used, and the like. The pressure applied by the pair of rollers is set so that the surface of the obtained transparent coating film has a predetermined smoothness and glossiness.

The transport time from the recording unit 101 to the heat roller pair, that is, the time interval between the recording process and the fixing process, depends on the ink absorption capacity of the recording medium, particularly the lower layer of the ink receiving layer, and the ink used for recording. It is appropriately selected depending on the physical properties and the like. In the present invention, the relationship between the layer thickness d of the lower layer of the ink receiving layer and the maximum ink recording speed v at the time of inkjet recording is set in accordance with the above-mentioned regulations, so that the time interval of these steps is effective. Can be shortened.

If necessary, the recording medium may be preheated after the recording is completed. This preheating treatment is carried out in order to promote the evaporation of the ink solvent component in the surface layer and the ink absorption in the lower layer of the ink receiving layer, and to make the fixing of the dye in the ink good during the laminating treatment. The temperature condition is appropriately selected mainly depending on the heat capacity of the recording medium, the constitution of the surface layer of the ink receiving layer used, and the like. For example, if the heating temperature is too high, there is a problem that the effective movement of the ink in the surface layer of the ink receiving layer is hindered, and the surface layer becomes cloudy, and if it is too low, the effect of heat treatment may be obtained. Can not. Specifically, it can be set at a temperature not higher than the glass transition temperature of the latex resin used for the surface layer of the ink receiving layer so that the desired effect can be obtained.

For this preheating treatment, for example, either one or both of a heater and a blowing means can be used. In particular, it is more effective that the temperature is higher if it is a means for exposing the recording medium to the atmosphere in the above temperature range, and that the air volume is larger if it is a blowing means. At this time, when paper restraining rollers or the like are arranged in order to efficiently conduct heat, these rollers or the like are arranged so as to contact the recording medium in the non-image area so as not to contact the recording surface of the recording medium.

[0023]

The present invention will be described in more detail with reference to the following examples. Example 1 According to the method described in US Pat. No. 4,242,271, aluminum octaxide was synthesized and hydrolyzed to produce an alumina slurry. Water was added to this alumina slurry until the solid content of the alumina hydrate became 5% by weight, and then the temperature was raised to 80 ° C. and the temperature was adjusted to 10%.
A aging reaction was performed to obtain a colloidal sol. The colloidal sol was further spray dried to obtain an alumina hydrate. Furthermore, this alumina hydrate is mixed with ion-exchanged water,
After being dispersed (solid content: 5% by weight), the pH was adjusted to 10 with nitric acid, and the aging time was adjusted to 5 hours to obtain a colloidal sol again. After desalting the colloidal sol, an appropriate amount of acetic acid was added to perform peptization. A part of the thus obtained colloidal sol was sampled, dried, and analyzed as the structure of alumina hydrate by X-ray analysis. The structure was pseudo-boehmite. Further, the colloidal sol that had been subjected to the above peptization treatment was concentrated to obtain a solution having a solid content of 15% by weight.

Next, polyvinyl alcohol (trade name: P
VA117, made by Kuraray Co., Ltd.) in ion-exchanged water
A 0% by weight solution was prepared, and this solution and a 15% by weight solution of the colloidal sol prepared above were used in such a manner that the solid content of the colloidal sol (alumina hydrate) and the solid content of the polyvinyl alcohol solution were 10:10 by weight. The mixture was mixed and stirred so that the mixture became 1 to obtain a dispersion liquid for preparing the lower layer.

This dispersion was die-coated on a polyethylene terephthalate (PET) film and dried to 40 μm.
A m-thick porous layer was obtained. Further, on this porous layer, a vinyl chloride-vinyl acetate latex having a solid content of 15% (trade name: VINYBLANN 602, manufactured by Nissin Chemical Industry Co., Ltd.) was die-coated and dried at 70 ° C. to obtain a porous latex having a thickness of about 5 μm. A surface layer consisting of layers was formed to obtain a recording medium. The content of particles of 0.14 μm (corresponding to a particle diameter of ⅕ of the average particle diameter) or less in this latex was 20% by weight or more.

The recording medium thus obtained was subjected to ink-jet recording and a transparent coating treatment (fixing treatment) for the surface layer under the following conditions by the apparatus shown in FIGS. Inkjet head: As shown in FIG. 2, four heads for yellow, magenta, cyan and black are used, and each head has 256 nozzles arranged in series in the paper feeding direction (direction orthogonal to the scanning direction). Then, the respective nozzle rows were arranged in parallel. Discharge voltage and pulse width: The discharge voltage is 9p from each nozzle
1 ink droplets are set to be ejected, and the ejection pulse is 1200 dpi in relation to the scanning speed by the carriage.
It was set to 10 kHz so that considerable recording could be performed.

The ink recording rate per color at this time, since the unit area (1 mm ²⁾ per about 1116 dots is driven, a 10.04 (nl / mm ^2). Since the carriage speed is about 211.6 (mm / sec), the ink recording speed at this time is 2.125 ( μl /
mm · sec). At this time, the maximum ink density at which ink is ejected simultaneously was set to about 2.8 colors (corresponding to recording at a recording density of 70% per unit area). Therefore, the maximum ink recording speed v here is
It becomes about 6 μl / mm · sec. Fixing process: The recording medium after recording is passed between the pair of heat rollers 105 and 106 shown in FIGS. 2 and 3 so that the surface of the ink receiving layer of the recording medium comes into contact with the roller 105 so that the surface layer of the ink receiving layer is removed. A transparent film was formed.

As the roller 105, an HTV silicone rubber layer having a thickness of 2 mm and an LTV silicone rubber layer having a thickness of 0.5 mm mirror-finished are formed on a peripheral wall of a cylindrical substrate (outer diameter 60 mm) having a halogen heater 120 built therein. As a roller 106, a cylindrical base body (outer diameter 60 m) having a halogen heater 120 built therein is formed by sequentially stacking layers.
m) on the peripheral wall of 2 mm thick HT as well as the roller 105
V 0.5 mm thick L with mirror finish on silicone rubber layer
Use a TV silicone rubber layer stacked structure,
The pressure was set by arranging these rollers so that the contact width (hereinafter referred to as the roller nip) was about 5 mm.

Further, the conveying speed is 10 mm / sec, the temperature is 1
The temperature was controlled at ± 5 ° C by the thermistor 107 at 60 ° C. Although this temperature control method uses the method of turning on / off the halogen heater 120 at a predetermined temperature, it may be a method of obtaining a predetermined heating temperature such as a method of controlling with an electric power value.

The time from the end of recording to the fixing process is the time from the end of recording in the recording head of the pattern used in the study to the roller nip, and was adjusted by the rotation speed of the conveying roller during that time, 30 seconds in this example. And In addition,
During the 30 seconds, it was confirmed that the ink supplied to the surface layer of the ink receiving layer had reached the lower layer containing amina hydrate by permeation of the surface layer.

The composition of the ink used is as shown below. Ink composition: Dye 3 parts by weight Glycerin 7 parts by weight Thiodiglycol 7 parts by weight Water 83 parts by weight Dye Yellow (Y) For ink: C.I. I. Direct Yellow 86 For magenta ink (M): C.I. I. Acid Red 35 For cyan (C) ink: C.I. I. Direct Blue 19
9 For black (Bk) ink: C.I. I. Food Black 2 With respect to the print obtained through the transparent coating treatment of the surface layer of the ink receiving layer by the above operation, the glossiness and the generation of cracks in the transparent coating formed as the surface layer on the image were evaluated by the following methods. The results obtained are shown in Table 1. (1) Glossiness A glossiness of 75 ° was measured using a digital variable angle glossmeter (manufactured by Suga Test Instruments Co., Ltd.) based on JIS-P-8142. (2) Generation of cracks The surface of the coating film obtained by the transparent coating treatment from the surface layer of the ink receiving layer was observed with an optical microscope to examine the presence or absence of cracks.

Further, after the recording in the above operation, a preheating treatment was carried out by passing the recording medium through a preheating region in which a heater was installed at a speed of 30 seconds. The temperature of the preheating region at that time is 30 to 90 ° C., preferably 40 ° C. because the glass transition temperature of the latex resin is about 90 ° C.
By setting the temperature to -80 ° C, effective preheating treatment could be performed.

In the above example, the maximum ink recording speed is set to the upper limit of the recording density per color (the maximum ink density of about 2.
Although it is set according to 8), it may be set according to the head scanning speed and recording density by the carriage.

Reference Example 1 A print obtained by performing recording medium preparation, image formation by ink jet recording and fixing treatment by a heat roller pair in the same manner as in Example 1 except that the thickness of the lower layer was 30 μm. evaluated. The results are shown in Table 1.
It was visually confirmed that the ink solvent remained in the upper layer of this recording medium even after 30 seconds from recording. The glossiness of the print after the fixing process was 60%, and cracks were observed in the coated surface layer.

Example 2 A vinyl chloride-vinyl acetate latex having a solid content of 15% (trade name: VINYBRAN 602, manufactured by Nissin Chemical Industry Co., Ltd.) was subjected to a centrifugal separation treatment (3000 rpm / 40 minutes), and the supernatant 4 was added.
0% was removed to obtain an average particle size of 0.7 μm and an average molecular distribution of 3
A latex solution having a content of particles of σ and a particle diameter of 0.14 μm or less and 1% by weight or less was obtained.

Then, a 40 μm-thick porous layer was formed on the polyethylene terephthalate film in the same manner as in Example 1 using the dispersion liquid for the lower layer prepared in Example 1, and then,
Then, the above latex solution is die-coated to 70
A recording medium was obtained by drying at 0 ° C. to form a surface layer composed of a porous latex layer having a thickness of about 5 μm.

Using this recording medium, image formation by ink jet recording and fixing treatment with a heat roller pair were performed in the same manner as in Example 1, and the obtained prints were evaluated. The results are shown in Table 1. In this example, it was confirmed that the ink had completely penetrated the surface layer within 10 seconds after recording, so the fixing process with the heat roller pair was performed 10 seconds after recording. Further, the glossiness of the print after the fixing process was 95%, and no crack was observed in the coated surface layer.

Example 3 A vinyl chloride-vinyl acetate latex having a solid content of 15% (trade name: VINYBRAN 602, manufactured by Nisshin Chemical Industry Co., Ltd.) was used as a microfiltration membrane (trade name: PMV313 / nominal pore size 0.25 μ).
m, manufactured by Asahi Kasei Kogyo Co., Ltd.) under the condition that the amount of pure water for substitution is 25 times that of the stock solution of latex, and the particle diameter is 0.14 μm.
A latex solution having the following particle content of 10% by weight was obtained.

Next, a 40 μm-thick porous layer was formed on the polyethylene terephthalate film in the same manner as in Example 1 using the dispersion for the lower layer prepared in Example 1, and then,
Then, the above latex solution is die-coated to 70
A recording medium was obtained by drying at 0 ° C. to form a surface layer composed of a porous latex layer having a thickness of about 5 μm.

Using this recording medium, image formation by ink jet recording and fixing treatment by a heat roller pair were performed in the same manner as in Example 1, and the obtained prints were evaluated. The results are shown in Table 1. In this example, it was confirmed that the ink had completely penetrated the surface layer within 10 seconds after recording, so the fixing process with the heat roller pair was performed 10 seconds after recording. Further, the glossiness of the print after the fixing process was 95%, and no crack was observed in the coated surface layer.

Reference Example 2 A print obtained by preparing a recording medium, forming an image by inkjet recording and fixing with a heat roller pair in the same manner as in Example 2 except that the lower layer has a thickness of 30 μm. evaluated. The results are shown in Table 1. The glossiness of the print after fixing processing by the heat roller pair after 10 seconds of recording was 55%, and cracks were observed in the coated surface layer.

Example 4 The lower layer has a thickness of 20 μm and the maximum ink recording speed is 3
A print medium was prepared, image formation by ink jet recording and fixing treatment by a heat roller pair were performed in the same manner as in Example 2 except that the print amount was ml / mmsec. The results are shown in Table 1. In this example, it was confirmed that the ink had completely penetrated the surface layer 10 seconds after the recording, so the fixing process was performed by the heat roller pair 10 seconds after the recording. Also, the glossiness of the print after the fixing process is 95%, the film of has been surface layer <br/> cracks were observed.

Reference Example 3 A print medium was prepared in the same manner as in Example 4 except that the lower layer had a thickness of 15 μm. Image formation by inkjet recording and fixing treatment by a heat roller pair were carried out, and the obtained print was evaluated. did. The results are shown in Table 1. The glossiness of the print after fixing processing by the heat roller pair after 10 seconds of recording was 60%, and cracks were observed in the coated surface layer.

Example 5 Example 1 was repeated except that a baryta paper (a paper having a basis weight of 150 g / m ^{2 and} a barium sulfate layer of 20 μm provided on a base paper) was used as a base material and the thickness of the lower layer was 20 μm. In the same manner as described above, a recording medium was prepared, an image was formed by inkjet recording, and a fixing process was performed with a heat roller pair, and the obtained print was evaluated. The results are shown in Table 1. In this example, it was confirmed that the ink completely penetrated the surface layer 30 seconds after the end of recording. The glossiness of the print after the fixing process was 60%, and no crack was observed in the coated surface layer.

Reference Example 4 A print obtained by performing recording medium production, image formation by ink jet recording and fixing treatment by a heat roller pair in the same manner as in Example 5 except that the thickness of the lower layer was 15 μm. evaluated. The results are shown in Table 1. In this recording medium, it was visually confirmed that the ink solvent remained in the upper layer 30 seconds after the recording, and the glossiness of the print obtained by the fixing treatment 30 seconds after the recording was finished was 30%, and the film was formed into a film. Cracks were observed on the surface layer.

Example 6 A recording medium was prepared in the same manner as in Example 2 except that the base material was baryta paper (the same as that used in Example 5) and the thickness of the lower layer was 20 μm. Forming and fixing processing with a heat roller pair were performed, and the obtained prints were evaluated. The results are shown in Table 1. In this example, it was confirmed that the ink had completely penetrated the surface layer after 10 seconds of recording, so that the fixing process was performed by the heat roller pair after 10 seconds of recording. Further, the glossiness of the print after the fixing process was 60%, and no crack was observed in the coated surface layer.

[0047]

[Table 1]

[0048]

EFFECTS OF THE INVENTION According to the present invention, since an effective transparent film-forming treatment can be carried out in a state where ink or ink components do not remain on the surface layer of the ink receiving layer containing a latex resin, high quality and weather resistance can be obtained. High print quality can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic view of an example of an image forming apparatus of the present invention.

FIG. 2 is a diagram showing the configuration and operation of a head in an example of the image forming apparatus of the present invention.

FIG. 3 is a cross-sectional view of an example of a heat and pressure processing member in the image forming apparatus of the present invention.

[Explanation of symbols]

1 Y color head 2 M color head 3 C color head 4K color head 5 carriage 101 recording section 102 transport roller 103 Intermediate tray 104 Reversing roller 105 heat roller 106 Lower heat roller 107 Thermistor 108 paper ejection roller 109 paper ejection roller 110 roller cleaning member 111 Paper output tray 112 roller pair

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-2-243355 (JP, A) JP-A-7-237348 (JP, A) JP-A-8-2090 (JP, A) JP-A-56- 99694 (JP, A) JP-A-9-11607 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/01 B41M 5/00

Claims (18)

(57) [Claims] 1. A method for forming an image covered with a surface layer composed of a transparent resin layer by ink jet recording, comprising: (a) an impermeable lower layer and a thermoplastic latex resin on a water impermeable substrate. A step of supplying ink droplets from the surface side to the recording medium provided with an ink receiving layer having a porous surface layer containing the ink by an inkjet method according to recording information, and (b) the step (a) A step of forming a transparent film on the surface layer of the ink-receiving layer when the image is formed by the ink supplied to the surface layer, transmitted through the surface layer, and absorbed in the lower layer. 1 selected from pigments and alumina hydrates
Including a filler or a binder made of two or more kinds, and the relation between the thickness d (μm) of the lower layer and the maximum ink recording speed v ( μl / mm · sec) during inkjet recording is d ≧ An image forming method, wherein the image forming method is 6.0 · v. 2. The compounding ratio of the filler and the binder is the weight.
The image form according to claim 1, wherein the ratio is 1: 1 to 30: 1.
How to do it. 3. The binder is polyvinyl alcohol,
At least selected from gelatin, starch and casein
The image forming method according to claim 1, which is one kind. 4. The average particle size of the latex resin is
In the range of 0.2 to 5 .mu.m, claims 1-3 distribution width of the particle size is within 3 [sigma], and the proportion of particles having a particle diameter of 1/5 or less of the average particle size of 10 wt% or less Noi
The image forming method according to Zureka. 5. The image forming method according to claim 1, wherein the latex resin is a vinyl chloride-vinyl acetate latex. 6. The image forming method according to claim 1 , wherein the transparent coating of the surface layer is a heat treatment at a temperature of a minimum film forming temperature of the latex resin contained in the surface layer or higher. 7. The transparent film of the surface layer, the image forming method according to claim 1 is a pressure treatment in the heating under the above minimum film-forming temperature of the latex resin contained in the surface layer . Wherein said water impermeable substrate, the image forming method according to claim 1 is a resin film. Wherein said filler is an image forming method according to any one of請<br/> Motomeko 1-8 is alumina hydrate. 10. A method of forming an image covered with a surface layer composed of a transparent resin layer by ink jet recording, comprising: (a) an ink-absorbing lower layer and a thermoplastic latex resin on a water-permeable substrate. A step of supplying ink droplets from the surface side by an inkjet method to a recording medium provided with an ink receiving layer having a porous surface layer, and (b) the ink by the step (a). A step of forming a transparent coating on the surface layer at a stage where an image is formed by the ink supplied to the surface layer of the receiving layer, transmitted through the surface layer, and absorbed in the lower layer thereof. And 1 selected from alumina hydrate
Including a filler or a binder made of two or more kinds, and the relation between the thickness d (μm) of the lower layer and the maximum ink recording speed v ( μl / mm · sec) during inkjet recording is d ≧ An image forming method, wherein the image forming method is 3.0.v. 11. The compounding ratio of the filler and the binder is
The image according to claim 10, which is in a volume ratio of 1: 1 to 30: 1.
Imaging method. 12. The binder is polyvinyl alcohol.
Less selected from sugar, gelatin, starch and casein
The image formation according to claim 10 or 11, wherein both are one kind.
Method. 13. The average particle size of the latex resin is
The range of 0.2 to 5 μm, the distribution width of the particle diameter is within 3σ, and the proportion of particles having a particle diameter of ⅕ or less of the average particle diameter is 10% by weight or less . Izu
An image forming method according to any one of the above. 14. The latex resin is vinyl chloride
The vinyl acetate latex as claimed in any one of claims 10 to 13.
An image forming method according to any one of the above. 15. The image forming method according to claim 10 , wherein the transparent coating of the surface layer is a heat treatment at a minimum film forming temperature of the latex resin contained in the surface layer or higher. 16. The image forming method according to claim 10 , wherein the transparent coating of the surface layer is a pressure treatment under heating at a minimum film-forming temperature of the latex resin contained in the surface layer. . 17. The image forming method according to claim 10 , wherein the water-permeable base material is plain paper, coated paper or baryta paper. 18. The method of claim 17, wherein the filler is, the image forming method according to any one of alumina hydrate <br/> claims 10 to 17.