JPS63166586A - Material to be recorded - Google Patents

Abstract

PURPOSE:To enhance the light-resistance of an image formed with a water-soluble dye, by a method wherein a silica previously surface-treated with a specific metallic compound is contained in the recording surface of a material to be recorded. CONSTITUTION:In a material to be recorded with an image by using a recording liquid containing a water-soluble dye, a silica surface-treated with one of a metallic soap, a hydroxide, a salt, and an oxide of a metal selected from among groups composed of Na, R, Ca, Mg, Al, Zn, Ba, Sr, or Sn or a mixture of two or more of the above compounds is contained. As a particularly preferable method for treating the silica with these compounds, a method wherein the metallic compound is added in the initial stage or the latter stage of aging reaction or gelation in the manufacturing process of the silica or a method wherein it is added in the initial stage of the reaction is employed. To contain the surface-treated silica in a substrate, for example, a method wherein the surface-treated silica is added in a paper making process to manufacture a paper is employed. This material to be recorded is manufactured by a method wherein the treated silica is added to a coating liquid and the coating liquid is coated on the substrate such as a paper and dried.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a recording liquid (hereinafter referred to as ink) containing a dye.
This technology relates to recording materials for forming images, and is particularly applicable to multicolor recording, in which small droplets of ink containing water-soluble dyes are ejected using various ejection methods and attached to the recording material. The present invention relates to an inkjet recording material.

(Prior Art) The inkjet recording method has attracted attention as a recording method that generates little noise, can print at high speed, and can print in multiple colors, and has been used in various applications as a method for obtaining hard copies of various figures and color images, including kanji. It is becoming popular.

Water-based inks are mainly used for inkjet recording in view of safety and printability.

On the other hand, conventionally, paper used for normal printing and writing has generally been used as the recording material.

However, as the performance of inkjet recording devices improves, such as faster recording, higher definition, or full color,
Recording materials are now required to have even more sophisticated properties.

That is, as a recording material for inkjet, it should absorb ink quickly and have a large ink absorption capacity;
The density of the ink dots is high, the color development is good, and the horizontal diffusion of the ink dots is not unnecessarily large.
In addition, it is necessary to satisfy various requirements such as the periphery being smooth and not blurred, and the recorded image having sufficient resistance to water, oxidizing gases in the air, and light.

Several proposals have been made to meet these demands. For example, in order to improve absorbency and ink bleeding, Japanese Patent Application Laid-Open No. 53-49113 discloses an inkjet recording paper in which a sheet made of wood pulp is impregnated with a water-soluble polymer.

Further, as examples of coated paper, JP-A-55-5830 discloses an ink-jet recording sheet with an ink-absorbing coating layer on a support, and JP-A-55-11829 discloses Inkjet recording sheets are disclosed in which two or more coating layers having different ink absorption properties are provided on non-size paper.

Further, the inkjet recording material described in JP-A-56-99693 contains a halogenated quaternary ammonium salt or the like to impart water resistance. However, it has been recognized that such measures to improve water resistance have the disadvantage that the light resistance of the recording agent (dye, etc.) is significantly reduced.

In addition, a recording paper containing silica has been proposed as a recording material for inkjet, and this recording material has various advantages as a recording material for inkjet, such as excellent color development. However, when recording is performed on the recording material with an ink containing a water-soluble dye, particularly a direct dye, an acid dye, or a food coloring agent, there is a disadvantage that the formed image has poor light resistance and discolors and fades. .

Also, JP-A-61-43593 and JP-A-61-
As seen in Japanese Patent No. 57379, it has been proposed to use silica together with magnesium sulfate or water-soluble aluminum salt to improve the light resistance of images, but these methods simply
Since the recording material is prepared as a mixed coating liquid by dispersing or dissolving the above components in water and adding an adhesive as a binder, the poor light resistance of silica is only slightly improved, and the The effects of their combined use, such as excellent color properties and reduced ink absorption, could not be said to be sufficient.

(Problems to be Solved by the Invention) An object of the present invention is to satisfy various problems that the prior art could not solve in the above-mentioned technical field.

In particular, the present invention aims to simultaneously improve the above-mentioned requirements in recording images using the inkjet recording method, particularly color development, light fastness, and water resistance. The objective is to improve the light resistance of images when a silica-containing recording material is used.

Another object of the present invention is to provide a new inkjet recording material that can always exhibit excellent recording properties even when using a wide variety of water-based inks containing water-soluble dyes.

The above and other objects are achieved by the invention as follows.

(Means for Solving the Problem) That is, the present invention provides a recording material for forming an image using a recording liquid containing a water-soluble dye, in which the recording material contains Na, Ca, Mg, etc. , AI, Zn, Ba, Br
A recording material characterized by containing silica surface-treated with one or a mixture of two or more of metal soaps, hydroxides, salts, or oxides of metals selected from the group consisting of .

Next, to explain the present invention in more detail, the main feature of the present invention is that the recording surface of the recording material is coated with silica that has been surface-treated in advance with the above-mentioned specific metal compound (hereinafter simply referred to as a treatment compound). By using silica whose surface has been treated with such processing agent compounds, these processing agent compounds can be simply mixed and used in the preparation of the recording material, for example, during papermaking or when adjusting the coating liquid. The main objective of the present invention, that is, the light fastness of images formed with water-soluble dyes is significantly improved compared to the case where the dyes are used.

The treatment agent compound that mainly characterizes the present invention is a metal soap, hydroxide, salt, or oxide of the above-mentioned specific metal, and examples of the metal soap include stearic acid, lauric acid, or other aliphatic acids and aromatic acids. It is a reactant with an acid, and its salts include chlorides, sulfates, nitrates, ammonium salts, acetates, carbonates, oxalates, silicates, and the like.

Further, it may be a double salt of the above metal or may have water of crystallization. Among the metals, Ca, Mg, AI
L and Zn are preferred from the viewpoint of bonding strength with silica, non-toxicity, non-coloring property, etc.

The processing agent compound used in the present invention is also used in East Germany.
NJ or more may be used in combination, and it is preferably used in a proportion of 0.1 to 30 parts by weight, particularly preferably 0.5 to 20 parts by weight, based on 100 parts by weight of silica. If the amount used is less than 0.1 parts by weight, the effect of the present invention will be insufficient, while if it is more than 30 parts by weight, the ink absorbency of the recording material will decrease and the color properties will decrease, which is not preferable.

The method for treating silica with the above-mentioned treating agent compound preferably includes a dry method and a wet method.

In the dry method, silica and a treatment compound are mixed, or powder of the treatment compound, its aqueous solution, or dispersion is added by a spraying method while stirring and mixing the silica to uniformly adhere the treatment compound to the silica. It's a method.

On the other hand, the wet method involves immersing silica in a treatment solution containing a treatment compound during the silica manufacturing process, or incorporating a treatment compound into a silica dispersion to perform gelation, ripening, and sedimentation, and reaction. It can be added from the beginning or sprayed during the drying process to treat the surface. Among these, particularly preferred are the method of adding the treating agent compound at the beginning of the aging reaction or gelation or later described, and the method of adding it from the early stage of the reaction, whereby the silica surface can be efficiently coated with the treating agent compound.

Note that the method is not limited to the above method, and any method may be used as long as the surface of the silica is previously treated with a processing agent compound before being included in the recording material.

The untreated silica used in the recording material of the present invention includes:
Any conventionally known natural or synthetic silica can be used, but particularly preferred ones have a specific surface area of 6 by the BET method.
0 g/rn' or more, preferably 80 to 700 g/rn
By using silica with such a specific surface area, it is possible to achieve excellent color development of the water-soluble dye in the ink and optimal ink dot shape and size.

The recording material of the present invention is made of various sheet materials such as conventionally known wood-free paper, medium-quality paper, processed paper, synthetic paper, plastic film, etc.; can get.

Any method may be used to incorporate the surface-treated silica into the base material, but for example, in the papermaking process of such a base material, a method of making paper by adding surface-treated silica described in 2. There is a post-treatment method in which the above-mentioned surface-treated silica is added and the base material is immersed therein, but any method may be used. In such a method, the object of the present invention can be achieved by adding the surface-treated wrinkle force to the recording material in such a range that the surface-treated silica accounts for about 5 to 30 parts by weight in 100 parts by weight of the recording material. best achieved.

On the other hand, in the recording material of the present invention of the type containing surface-treated silica in the coating layer on the surface of the substrate, the above-mentioned treated silica is added to a coating liquid for a substrate such as paper, and the coating layer is coated with the treated silica. It is manufactured by applying a liquid onto a substrate and drying it. Other components of the coating liquid in this case include conventionally known inorganic pigments such as clay, talc, diatomaceous earth, calcium carbonate, calcium sulfate, barium sulfate, titanium oxide, zinc oxide, satin white, aluminum silicate, and lithopone. Organic pigments such as styrene plastic pigments, acrylic plastic pigments, microcapsules, urea resin pigments, etc.: starch, gelatin, casein, gum arabic, sodium alginate, carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate, etc. Water-soluble polymers: Synthetic resins such as synthetic rubber latex Latex: Organic solvent-soluble resins such as polyvinyl butyral and polyvinyl chloride: Furthermore, dispersants, fluorescent dyes, PL+I agents, antifoaming agents, lubricants, preservatives,
Various additives such as surfactants and waterproofing agents can be mentioned.

Among these additives, the water resistance agent is a conventionally known 7-terminal that dissociates and exhibits cationic properties when dissolved in water.
, oligomers or polymers can be used.

The solid content of the coating liquid is preferably about 1 to 50% by weight, and the coating liquid can be coated by a known method such as a roll coater.
It is coated onto the substrate in an amount of usually about 1 to 50 g/m'' (dry coating amount) using a dry coating method, a blade coater method, an air knife coater method, etc. Preferably about 2 to 30 g/m2 (dry coating amount) ) Coating.

As described above, the recording material of the present invention is provided.

The ink referred to in the present invention is an ink consisting of a water-soluble dye, a liquid medium, and other additives. As the water-soluble dye, water-soluble dyes such as direct dyes, acid dyes, and food colorings are preferably used.

For example, direct dyes include C, 1, Direct Black 2, 4, 9, 11.14
．． 17.19.22.27.32.36.38.41.
48.49.51゜56.62.71.74.75.7
7.78.80.105, 106.107.108
, 112, 113.117.132, +46.
154.194.

1. Direct Yellow 1, 2, 4.8.1+.

12.24.26.27.28.33.34.39.4
1.42.44.48.50.51.58.72.85
．． 86.87.88.98.100%110: G, 1. Direct Orange 6, 8, 10.26
．． 29.39.41.49.51.102.

1. Direct Red 1, 2, 4.8.9.11
．． 13.17.20.23.24.28, :lI, 3
3.37.39.44.46.47.48.51.59
．． 62.63.73.75.77.80.81, 83.
84.85.90.94.99.101 %108゜1
10, 145, 189.197, 220, 2
24, 225.226, 227.230; 1. Direct Violet l, 7, 9.1
2.35.48.51.90.94: c, i, direct blue 1.2, 6, 8. +5.22.25.34.
69.70.71.72.75.76.78.80゜old, 82.83.86.90.98.106, 108
, II, 120, 123% 158.163.165
, 192.193.194.195.196 , 19
9, 200, 201.202.203, 207
, 218.236.237.2:19 , 246.25
8: c, r, direct green I, 6, 8.28.
33.37.63.64; C, 1, Direct Brown IA, 2, 6.25
．． 27.44.58.95, too, to+
% 106, 112, 173.194,
195, 209.210, 211; As acidic dyes, C,1, acid black l,2.7,
16.17.24.26.28.31.41.48.5
2.58.60.63.94.107, 109,
112, 118.119, 121.122,
131, 155.156.

c', r, acid yellow 1.3.4,7,11.
12.13.14.17.1B, 19.23.25.2
9.34.36.38.40.41.42.44.49
．． 53.55.59.61.71゜72.76.78.
99.111% 114, 116, 122゜1
35, 161, 172.

C, 1, Acid Orange 7.8, l0133.56
．． 64; C31, Acid Red 1, 4.6, 8, +3.14
．． 15.18.19.21.26.27.30.32.
34.35.37.40.42.51.52.54.5
7.80.82.83.85.87.88.89.92
．． 94.97.106, 108.110.119.1
29.131% 133, 134, 135, 15
4, +55.172% 176, +80.184.
186.187.243.249.254, 256.
260.289,:l17,318;c,r,
Acid Violet 7.11, +5.34.41
．． 43.49%75; C, 1, Acid Blue 1, 7.9, 22.23.2
5.27.29.40.41.43.45.49.51
．． 53.55.56.59.62.78.80.81.
83.90.92.93.102, +04, Ill
, 113 , 117 , 120% 124 , 126
．． 145, 167, 171%175, +83.2
29.234.236: C, 1, Acid Green 3.9.12.16.19.
20.25.27.41; (:, 1. Acid Brown 4.14: Furthermore, as food colorants, C, 1, Food Black 2; C, t, Food Yellow 3, 4, 5: C, 1, Food Red 2.3.7, 9.14.52.87.92.
94.102, 104.1G5, 106;
C, 1, Food Blue 1, 2; C, 1, Food Blue 1, 2; C, R, Food Green 2.3, etc., but are not limited to these, of course.

These water-soluble dyes are generally used by being dissolved in water or a liquid medium consisting of water and an organic solvent, and the liquid medium components preferably include water and various water-soluble organic solvents. Although mixtures may be used, it is preferred to adjust the water content in the ink to be within the range of 20 to 90% by weight.

Examples of the water-soluble organic solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, 5ec.
- Alkyl alcohols having 1 to 4 carbon atoms such as butyl alcohol, tert-butyl alcohol and isobutyl alcohol; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketone alcohols such as acetone and diacetone alcohol; tetrahydrofuran; Ethers such as dioxane: polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, 1.2.6-hexandriol, thioglycol,
Alkylene glycols in which the alkylene group has 2 to 6 carbon atoms, such as hexylene glycol and diethylene glycol; glycerin: ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl)
Examples include lower alkyl ethers of polyhydric alcohols such as ethers. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether are preferred. Polyhydric alcohols are particularly preferred because they are highly effective as wetting agents to prevent nozzle clogging caused by evaporation of water in the ink and precipitation of water-soluble dyes.

Solubilizing agents can also be added to the ink. Typical solubilizers are nitrogen-containing heterocyclic ketones, and their intended effect is to dramatically improve the solubility of the 7-soluble dye.

For example, N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidinone are preferably used.

Ink prepared from such components has its own recording properties (signal response, droplet formation stability, ejection stability,
It has excellent long-term continuous recording performance, ejection stability after a long recording pause), storage stability, and fixation to recording media, but in order to further improve these properties, various additives are added. You may further contain. For example, viscosity regulators such as water-soluble resins such as polyvinyl alcohol and cellulose; various cationic, anionic or nonionic surfactants; surface tension regulators such as jetanolamine and triethanolamine; pH regulators using buffer solutions. etc. can be mentioned.

Further, in order to prepare ink used in an inkjet recording method in which the ink is charged, a resistivity adjuster such as inorganic salts such as lithium chloride, ammonium chloride, and sodium chloride is added. In addition, when applicable to an inkjet recording method in which ink is ejected by the action of thermal energy, thermal physical property values (for example,
Specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted to A.

(Function) In the present invention, the mechanism of how the surface-treated silica acts on the ink and the water-soluble dye therein in the recording material of the present invention is not clear at present. However, water-soluble dyes are oxidized by oxidizing gases in the air such as oxygen and ozone as well as by oxidation in the air due to the catalytic action of untreated silica, especially synthetic fine particle silica with a specific surface area of 60 g/rn'' or more by the BET method. It is presumed that discoloration and fading occur because it becomes susceptible to oxidation due to the interaction between sexual gases and light.

As a result of extensive research, the present inventors have discovered that there is a correlation between the solid acid strength of the pigment or filler in the recording material, especially its ink-receiving layer, and the discoloration and fading of the recorded image. .

The surface treatment of silica with the specific treatment agent compound in the present invention inactivates the active acidic sites on the silica surface, which are assumed to be responsible for this catalytic action, and
Therefore, it is thought that in the recording material of the present invention, the oxidation reaction caused by the silica of the water-soluble dye is suppressed, and the light resistance (storability) of the recorded image is significantly improved.

(Effects) Silica-containing recording materials are known to exhibit excellent color development with ink as conventional recording materials, especially recording materials for inkjet recording methods. When recording was performed on a recording material containing water-soluble dye with an ink made of a water-soluble dye, the light resistance of the formed image was extremely low. By incorporating the silica into the recording material, the light resistance, which was a drawback of the silica-containing recording material, can be significantly improved without losing any of the excellent color development properties inherent in the silica-containing recording material.

(Examples) Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In the text, parts or percentages are based on weight unless otherwise specified.

Examples 1 to 5 Silica used in the present invention was prepared as shown in Table 1 below.

Next, a coating liquid having the following composition was prepared using each of the silicas shown in Table 1.

Next, general high-quality paper (silver ring: basis weight 64 g) was used as a base material.
/m', manufactured by Sanyo Kokusaku Valve ■), and applied the following coating liquids on this substrate at a dry coating weight of 12 g/m2.
The recording material of the present invention was obtained by coating with a bar coater and drying by a conventional method.

Silica in the table: 100 parts Polyvinyl alcohol (manufactured by Kuraray, PVA 117) 50 parts Water 400 parts Comparative Example 1 For comparison, untreated silica A was used in place of surface treatment strength B in the coating solution of Example 1. A recording material of a comparative example was prepared in the same manner as in Example 1 except that .

Comparative Example 2 For comparison, instead of the surface-treated silica B used in Example 1, a coating solution was prepared by simply mixing silica A and calcium chloride, a treatment compound, at room temperature during the preparation of the coating solution. A recording material of a comparative example was prepared in the same manner as in Example 1 in other respects.

Comparative Example 5 A recording material of a comparative example was prepared in the same manner as in Example 1 except that commercially available silica (Syroid 74, manufactured by Fuji Davison Chemical, specific surface: a 300 g/rn'') was used for comparison.

Usage Example 1 For the recording material of the present invention and the recording material for comparison,
Inkjet recording was performed using the following ink using a Canon BJ-80 inkjet printer, and the light resistance of the solid printed portion of the resulting image was evaluated.

Light resistance is measured using Atlas Fademeter for 50 hours of irradiation (6
3°C, 65% RH%, 0.39 W/bar), and using a high-speed spectrophotometer model CA-35 (Murakami Color Research Institute Group),
The color difference (ΔEab'') from that of the non-irradiated sample was determined and used as a measure of light resistance.The smaller the value, the better the light resistance.The results are also listed in Table 1 below.

C, 1, Food Black 2 2 parts diethylene glycol 15 parts polyethylene glycol 20 parts water
70 copies (as shown in Table 1 below)
The light resistance of the recorded image obtained using the recording material of the present invention is significantly improved compared to that of the comparative example.
Furthermore, the recorded images according to the present invention were clear and had high resolution without ink bleeding even when a water-based ink containing a water-soluble dye was used. It should be noted that while the recording materials of Examples were excellent in color development, the recording materials of Comparative Examples were poor in both ink absorption and color properties.

Examples 6 to 10 LBK with freeness of 350 mj ICSF as raw material valve
P was used, and silica slurry shown in Table 2 below was added as a filler to the valve solid content at 30% (dry weight), respectively.
As a retention aid, cationic starch (manufactured by Tamago National, CATOF) was added at 0.2% based on the solid content of the valve.
This was added internally, and paper was made into a paper having a basis weight of 65 g/m'' using a TAPPi standard sheet former to obtain a base paper.

Next, using a 2% concentration polyvinyl alcohol solution (manufactured by Kuraray, PVA C3T) as a coating liquid, the above-mentioned base paper was coated with a size press device so that the dry coating amount was 1.0 g / ♂, The recording material of the present invention was obtained by drying by a conventional method.

Comparative Example 3 For comparison, a recording material of Comparative Example was prepared in the same manner as in Example 6 except that untreated silica A was used in place of the surface-treated silica B of Example 6.

Comparative Example 4 For comparison, instead of the surface-treated silica C used in Example 7, silica A and magnesium hydroxide, a treatment agent compound, were simply mixed at room temperature and added internally, but the rest was the same as in Example 7. A recording material of a comparative example was prepared.

Usage Example 2 Inkjet recording was performed on the recording materials of the present invention and comparative examples using inks having the following compositions, and the light resistance was evaluated in the same manner as in Examples 1 to 5. The results are shown in Table 2 below.

C, 1, Direct Blue 86 2 parts glycerin 5 parts polyethylene glycol #300 10PtS diethylene glycol
20 parts water
65 copies As shown in Table 2 below, the light resistance of images obtained using the recording material of the present invention was significantly improved compared to that of the comparative example. Further, the recording material of the comparative example had poor ink absorption and color property, but the recording material of the present invention was good in both.

γ 1 Town (Examples 1 to 5, Comparative Example 1.2.5) Silica C: Immediately after aging for 40 minutes in the reaction of silica A described below, 3% calcium chloride was added to the silica. Silica B was obtained in the same manner as Silica A except that it was further aged for 20 minutes.

Light resistance (ΔEab'') 5 Example 1 Silica C: Silica C was prepared in the same manner as Silica A except that 10% of magnesium hydroxide was added to the perforation strength immediately before drying with a spray dryer in the reaction of Silica A described below. I got it.

Light resistance (ΔEab") 4 X 5 examples Nisilica D: Silica D was obtained in the same manner as Silica A, except that 6% of zinc oxide was added to the silica immediately after alkali neutralization in the reaction of Silica A described below. Ta.

Light resistance (ΔEab”) 4 comb group 4 Silica E: Silica E was obtained in the same manner as Silica A except that 15% of calcium laurate was added to the silica during spray dryer drying in the reaction of Silica A described below. Ta.

Light resistance (ΔEab”) 3 Inumu 1 Silica F: Silica F was prepared in the same manner as Silica A, except that 2% of aluminum hydroxide was added to the silica before the reaction of Silica A, which will be described later. Obtained.

Lightfastness (ΔEab") 2 Le Mosquito J Silica A: Put 10 grams of commercially available sodium silicate and 35 m3 of water into a reaction tank, and add sulfuric acid (220 g/lJ 3.2 m') over about 15 minutes while stirring. Steam was blown into this liquid while stirring, and the temperature was raised to 90° C. over 60 minutes. Thereafter, aging was performed at the same temperature for 40 minutes, and the alkali was neutralized with sulfuric acid to complete the reaction.

This solution is then filtered, washed with water, and sprayed. After drying with a dryer, grind and compare. Silica A with a surface area of 250 g/♂ was obtained.

Light resistance (ΔEab') 2 full mosquito silica A Treatment method No treatment (simply mix 3% calcium chloride to silica when preparing the coating solution) Light resistance (ΔEab') 15 Comparative example 5 Light resistance (ΔEab@) 25 to 2 -- (Examples 6 to 10, Comparative Example 3.4) ΔEa
b”Example 6B 4 Example 7C5 Example 8D 3 Example 9E 3 Example 10 F 2 Comparative Example 3
A 15 Comparative Example 4 A” 10 A1; No treatment (simply mixing magmedium hydroxide at 10% with respect to silica).

Claims (5)

[Claims] (1) In a recording material for forming an image using a recording liquid containing a water-soluble dye, the recording material contains Na, K,
, Ca, Mg, Al, Zn, Ba, Br and Sn. A recording material characterized by containing: (2) The recording material according to claim (1), wherein the recording material is paper, and the surface-treated silica is included in the paper. (3) The recording material according to claim (1), wherein the recording material is paper, and the surface-treated silica is included in a coating layer formed on the surface of the paper. (4) Silica has a specific surface area of 60 g/m^ by BET method.
The recording material according to claim (1), which is two or more synthetic silicas. (5) Claim No. (1) for inkjet use
Recording material described in section.