JPS6285982A - Recording medium and recording method - Google Patents

Abstract

PURPOSE:To enhance color development properties, light resistance and water resistance, by incorporating an amino acid into a silica-containing recording medium. CONSTITUTION:This recording medium comprises a base consisting of a converted paper, a synthetic paper, a plastic film or the like, with silica and an amino acid provided in or on the base. Silica is preferably a synthetic fine particulate silica having a specific surface area measured by the BET method of at least 100m<2>/g. The amino acid may be any of various alpha-, beta- or gamma-amino acids and other amino acids. Particularly preferable amino acids include sulfur-containing amino acids, such as methionine and cystine, and hydrochlorides thereof. To incorporate silica and the amino acid into the base, for example, the two components may be added simultaneously or separately in the process of making a paper for obtaining the base. A recording medium of the type in which the two components are contained in a coated layer on the surface of the base can be produced by adding the two components to a coating liquid, applying the resultant coating liquid to the base, and drying the applied liquid. With the amino acid or a mixture thereof incorporated into a silica-containing recording medium, the light resistance of the medium can be enhanced without loosing the excellent color development properties inherent in the silica-containing recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a recording medium and a recording method, and more specifically, it provides a recorded image having excellent properties such as color development, light fastness, and water resistance. The present invention relates to an improved ink-side recording medium and an ink-side recording method using the medium.

(Prior Art) The ink-end recording method uses various recording liquid (hereinafter referred to as ink) ejection methods (for example, an electrostatic suction method, and a method that applies mechanical vibration or displacement to ink using a piezoelectric element). , a method in which ink is heated and foamed, and the resulting pressure is used) to generate small droplets of ink, fly them, and attach some or all of them to a recording medium such as a piece of paper for recording. However, it is attracting attention as a recording method that generates little noise and can perform high-speed printing and multicolor printing.

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

On the other hand, conventional paper has generally been used as a recording medium. When recording on such paper using liquid ink, it is generally necessary that the ink does not bleed onto the recording medium and cause the print to become blurry, and that the ink is kept dry as soon as possible after recording. It is desirable not to accidentally contaminate the paper surface.

That is, in the inkjet recording method.

(1) Even if the ink is quickly absorbed into the recording medium, the ink deposited later will not mix with the ink deposited earlier, disturb the ink dots, or flow out; (2) Ink liquid (3) The shape of the ink dot should be close to a perfect circle, and the periphery thereof should be smooth.

(4) The density of the ink dots is high and the periphery of the tonto is not blurred. (5) The height of the recording medium is high and the contrast with the ink dots is large. (6) The color of the ink does not change depending on the recording medium. (7) It is necessary to satisfy various requirements such as (7) dimensional fluctuations (for example, wrinkles, stretching) of the recording medium are small before and after recording.

By the way, since the conventional ink ciendo recording method mainly uses water-based ink, there is a problem that the recorded image lacks water resistance, and when it gets wet with water, the ink bleeds and the characters etc. become illegible. It was also requested that the issue be resolved.

For example, the inkjet recording medium described in JP-A-56-99693 contains a quaternary ammonium halide 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, paper containing silica has been proposed as an inkjet recording medium, and this recording medium has various advantages as an inkjet recording medium, such as excellent color development of the recording agent. water soluble dye,
In particular, when recording is performed with ink using a direct dye, acid dye, or food coloring agent as a recording agent, there is a disadvantage that the formed image has poor light resistance and discolors and fades, although the reason is not clear.

(Problems to be Solved by the Invention) The first objective of the invention is to satisfy all the problems that the prior art could not solve in the technical fields listed in L.

In particular, one object of the present invention is to simultaneously meet the various requirements, particularly color development, light fastness, and water resistance, in recording images using an inkjet recording method.
The purpose of this invention is to improve the light resistance of images when using silica-containing recording media that have excellent color development but are poor in light resistance.

Another object of the present invention is to provide a novel ink-side recording medium and recording method that can consistently exhibit excellent recording characteristics even when using a wide variety of water-based inks containing water-soluble dyes.

``Bipedal and other objects are achieved by the invention as follows.

(Disclosure of the Invention) That is, the present invention consists of two inventions, the first of which is a recording medium characterized by containing both silica and an amino acid, and the second invention is a recording medium characterized by containing silica and an amino acid. This is a recording method characterized by recording on a recording medium containing both silica and amino acids using ink containing a water-soluble dye.

Next, to explain the present invention in more detail, the main feature common to the present invention is that various recording media, especially images that have conventionally been excellent in color development, have insufficient light fastness. By adding an amino acid to a silica-containing recording medium, the light fastness of an image formed with an ink, particularly an ink containing a water-soluble dye, is significantly improved while maintaining the excellent color development properties. Based on this knowledge, the present inventor has achieved the object of the present invention.

Next, to explain the recording medium that is mainly characterized as uninvented, the recording medium of the present invention is characterized by combining various conventionally known recording media with specific compounds, that is, silica and amino acids. With such a configuration, the object of the present invention is achieved.

The recording medium of the present invention is obtained by using various types of recording V-types as a base material, such as conventionally known paper, processed paper, synthetic paper, plastic film, etc., and adding silica and amino acids to the base material.

As the silica used in the recording medium of the present invention, any conventionally known natural or synthetic silica as a filler can be used, but particularly preferred ones have a specific surface area of 7 toom2/g or more by the BET method. is 100-700
m'/g (7) is a synthetic fine particle silica, and by using silica with such a specific surface area, excellent color development of the water-soluble dye in the ink and optimal ink dot shape and size are achieved. be able to.

Furthermore, the amino acids used in the present invention may be any conventionally known α-1β- or γ-amino acids, such as glycine, alanine, valine, leucine, inleucine, serine, threonine, cysteine, methionine, and asparagine. , glutamine, aspartic acid, glutamic acid, lysine, arginine, phenylalanine, tyrosine, pronin, hydroxyproline, tryptophan, histidine, and salts thereof. Among these, particularly preferred are sulfur-containing amino acids, such as methionine. , cysteine and their salt ugliness a! etc.

Although any method may be used to incorporate silica and amino acids into the base material, for example.

A paper manufacturing method in which these two components are added simultaneously or separately in the paper making process of such a base material, or a post-treatment method in which these two components are added to a paper impregnating liquid and the base material is immersed in this. There are various methods, but any method may be used.

In such a method, the addition of two components to the recording medium■
found that the objects of the present invention are best achieved by setting the silica to about 5 to 30 parts by weight and the amino acid to about 0.05 to 10 parts by weight in 100 parts by weight of the recording medium. .

Although it is effective to some extent even outside these ranges, there is a risk that the balance between color development and light fastness of the formed image will be lost.

On the other hand, (the recording medium of the present invention of the type containing the above-mentioned two components in the coating layer on the surface of the material is produced by adding the above-mentioned two components to a coating solution for a base material such as paper, It is produced by coating As on the base material and drying it.Other components of the coating liquid in this case include conventionally known clay, talc, diatomaceous material, calcium charcoal, and calcium sulfate. , MM barium, titanium oxide, zinc oxide, satin white, aluminum silicate, lithopone, and other inorganic pigments: starch, gelatin, casein, gum arabic, sodium alginate, carpogysimethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate Water-soluble polymers such as synthetic rubber latte.

Synthetic resin latinx such as wax: polyhinylpetyral,
Organic solvent-soluble resins such as polyvinyl chloride; and various additives such as dispersants, fluorescent dyes, pH'A regulators, antifoaming agents, lubricants, preservatives, surfactants, and waterproofing agents can also be mentioned.

The solid content of the coating solution is preferably about 1 to 50% by weight. ~50g/m'' (dry coating)
is coated on the base material 1-. Preferably, it is applied in an amount of about 2 to 30 g/m' (dry coating amount).

Silica-containing recording media are known to exhibit excellent color development with ink as conventional recording media, especially recording media used in the ink-side recording method. However, according to the present invention, when recording is performed using ink made of a synthetic dye, the light fastness of the formed image is extremely low. By including it in the recording medium, silica-containing 1
The light fastness, which had been a drawback of recording media, was significantly improved without losing any of the excellent color development properties inherent in recording media.

A second invention of the present invention is an invention of an inkjet recording method using the recording medium of the present invention as described above, and as long as the ink used in the recording method contains a water-soluble dye, conventionally known inks can be used. Either can be used.

As the water-soluble dye that is an essential component of the ink used in the inkjet recording method of the present invention, water-soluble dyes such as direct dyes, acid dyes, and food colorings are preferably used.

For example, as a direct dye, C,! , Direct Black 2.4, 9.11.14
．． 17.19.22.27.32.36.38.41.
48.49.5+, 56.62.7! , 74.75.7
7.78.80.105, 106.107, 10
8, 112.113, 117, 132,
148.154, 194: C, t, direct yellow 1.2.4.8. ll,
12, 24. 2B, 27.28.33.34.39.
41.42, 44.48, 50, 51, 58. 72
, 85, 86, 87, 88, 98.100 , +
10.

c, r, direct orange 6,8.10.2B,
29.39, 41, 49.51, 102; C, 1, Direct Red 1.2.4.8.9.1+
, 13, 17.20.23.24.28.31. 3
3.37.39. 44.46, 47, 48.51.
59.62.63.73.75,? 7. 80.81,
．． 83, 84, 85. 90, 94. 99, +01
, 108. 110, 145, 189
, +97, 220, 224,
225. 22B, 22? , 230
.

c, r, direct eyelid l,'?
,9. 12, 35, 48, 51.90, 94;C
, 1, Direct Blue 1.2. +3.8.15.2
2, 25, 34.69.70.71.72.75.7
6.78.80.81, 82, 83, 86, 90, 98
, 106 , 10B , +1°120 ,
123, 158, 183, 185
, 192 , 193 .

194, 195, 19fl, +9
9, 200, 20+, 202. 2
03, 207, 218, 238,
237, 239, 246. 258; C1, tie left green 1.6, 8, 28.33
．． 37, 63, 64; C, 1, tie left brown IA, 2, 6, 25
．． 27゜44.58.35.100, 101.10
G, 112, 173°194, 195, 2
09, 210, 2+1.

As an acid dye, C,1, acid black 1.2
．． 7.1B, 17.24.26.2B, 31.41.
48.52゜58.60.63.94. 10? ,
+09, 112, 118.

119, 121, 122, +31, 155
, 156; C, 1, acid yellow 1. 3,
4.7, 11゜12.13.14.17.18.
19.23.25.29, 3.4.3B, 38, 40.
41.42.44.49.53.55.59.61.7
1°72, 7G, 78.99. 111, 114
, 116.122.135, 161.172.

C, 1, acid orange 7.8, to, 3
3.58.64: c, r, acid red 1.4, 6, 8, 13
．． 14゜15.18.19.21.26.27.30.
32.34.35.3? .

40.42.51.52.54.57.80.82.8
3.85.87.88.89.92.94,97.10
B, 108, 110. 119.

129, 131, 133, 134
, 135 , 154 , 155 . 172
, 178 , 180 , 184 , 18
8, 187. 243. 24'l, 254
．． 25B, 260. 289. 317. 31
8.

C, 1, Acid Wind Iolet 7.11. +5
．． 34.41.43.49.75; C,! , Acid Blue 1, 7.9.22.23.2
5.27.29.40.41.43.45.43.51
．． 53.55.56.59, 62.78.80.81.
83.90.92.93.102゜104, 111
, 113, +17, 120, 124, 1
2B, +45, 187, 171, 1?5,
183, 229, 234.236; C, 1, acid green 3.9, 12.16, +9.
20.25.27.41°C, 1, acid brown 4.14: Furthermore, as food-grade colored barley.

c, r, food black 2: C,! , Food Yellow 3,4.5;c, 1. Hood Red 2.3, 7, 9, 14.52.87°9
2, 94.102, 104, 105, 106:
Examples include C,1, Foot Eye Iolet 2; C,1, Food Blue 1.2: C,1, Foot Green 2.3, but are of course not limited to these.

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 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%.

Examples of the water-soluble organic solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, 5ec-
Butyl alcohol, tert-butyl alcohol, isobutyl alcohol.

Alkyl alcohols having 1 to 4 carbon atoms such as; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketone alcohols such as acetone and diacetone alcohol; Ethers of tetrahydrofuran and oxanekasa: polyethylene glycol , holipropylene glycol Kasa's polyalkylene glycols: ethylene glycol, propylene glycol, 1,2.6-
Alkylene glycol 1 (hexane), diol, thioglycol, hexylene glycol, diethylene glycol, etc.
alkylene glycols containing 2 to 6 carbon atoms;
Glycerin; Examples include lower alkyl ethers of polyhydric alcohols such as ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, and triethylene glycol monomethyl (or ethyl) ether. Among these many water-soluble organic solvents,
Preferred are polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether. 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 water-soluble dyes in liquid media.

For example, N-methyl-2-pyrrolidone and l,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 long-term recording medium W), storage stability, and fixing property to recording media, but in order to further improve these properties, various additives are added. An agent may be further included. For example, viscosity modifiers such as water-soluble resins such as polyvinyl alcohol and cellulose; various cationic, anionic or nonionic surfactants; surface tension of jetanolamine, triethanolamine, etc.
3J adjuster; pH adjuster using a buffer solution, etc. can be mentioned.

In addition, in order to prepare ink used in an inkjet recording method that charges the ink, 11! Lithium chloride, 11! Ammonium chloride, 11! A resistivity adjuster such as an inorganic salt such as sodium chloride is added. When applied to an inkjet recording system in which ink is ejected by the action of a mature energy key, thermal physical property values (eg, specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted.

In the method of the present invention, the inkjet recording method for performing recording by applying the above-mentioned ink to the recording medium effectively releases the ink from the nozzle and applies the ink to the recording medium, which is a projectile object! Any method can be used as long as it obtains the information, and a representative example of such methods is, for example, IEEE Trans Accordion on Industry Applications (IEEE Trans.
actions onIndustry Appl
cations) Vat, IA-13, No.
, 1 (February/March 1977 issue), IJ Kei Elect A-Kus April 1978 t9ut;, January 1973 290
No. and 1974 5 J'] 8 E, marked in No. 1, 1
It is arranged. The methods described and circled above are suitable for the method of the present invention. To explain some of them, there is an electrostatic attraction method. In this method, acceleration is There is a method in which a strong electric field is applied between the ink particles and the nozzle, and the ink particles are drawn out one after another from the nozzle, and while the drawn ink flies between the deflection electrodes, an information signal is transferred to the deflection electrodes and recorded. There is a method of ejecting ink droplets in response to an information signal without deflection, and both methods are effective for the method of the present invention.

The second method is to forcibly eject minute ink particles by applying high pressure to the ink with a small pump and mechanically vibrating the nozzle with a crystal oscillator. At the same time as the injection, it is charged according to the information signal. When the charged ink particles pass between the deflection electrode plates, they are deflected according to the charge level. Another method that utilizes this method is called the microdot ink side method. In this method, the ink pressure 1 excitation condition is kept within a certain range of appropriate values, and two types of ink particles, large and small, are collected from the nozzle tip. This method generates droplets and uses only the medium and small droplets for recording. The feature of this method is that it is possible to obtain a group of minute droplets even with a nozzle diameter as large as conventional ones.

A third method is a piezo element method, in which a piezo element is used as a pressure means for applying pressure to the ink, rather than a mechanical means such as a pump as in other methods. This method applies an electric signal to a piezo element to cause mechanical displacement, thereby applying pressure to the ink and ejecting it from a nozzle.

In addition, an inkjet method is disclosed in Japanese Unexamined Patent Publication No. 54-51837, in which the ink subjected to the action of thermal energy undergoes a sudden change in volume, and the acting force due to this state change causes the ink to be ejected from the nozzle. The point method can also be used effectively.

According to the present invention as described above, it is possible to provide an image that simultaneously has significantly superior color development and light fastness compared to the conventional method using a recording medium. By using an ink made of pigments, it is possible to provide images that have excellent quality not seen in conventional examples, particularly excellent color development and light fastness at the same time.

Furthermore, according to the present invention, the ink is quickly absorbed into the recording medium, and even when ink of different colors is repeatedly deposited on the same spot within a short period of time, there is no ink flow or oozing phenomenon, and high resolution can be achieved. A clear image can be obtained. Therefore, the recording medium and recording method of the present invention can be used not only for general recording but also for general recording.
It is particularly suitable as a recording medium and recording method for inkjet recording.

Hereinafter, Unexploded No. 11 will be further explained in detail according to Examples and Comparative Examples. However, unless otherwise specified, parts or percentages in the text refer to assembly standards.

Example 1 As a base material, the size degree based on JISP8122 is 35
Use second-quality paper (Tsubo+, (64g/m')) and dry coat the coating liquid with the following composition on this base material: 1
Then, it was coated with a blade coater at a rate of 10 g/m' and dried by a conventional method to obtain a recording medium of the present invention. Further, for comparison, a coating liquid containing no amino acid was prepared and coated in the same manner as a recording medium of a comparative example.

Synthetic silica (Fuji Davison Chemical, Cyroid 40
4. Specific surface Ja340m2/g) 100 parts polyvinyl alcohol (manufactured by Kuraray, PVA117)
50 parts amino acid
X part water
400 copies of the recording medium were subjected to an inkjet recording method using the following ink, and the light resistance of the solid printed portion of the resulting image was evaluated.

Light resistance is measured using a xenon fade meter for 30 hours of irradiation (4
0℃, 65% RH 155mW/Cm') L, using a high-speed spectrophotometer model CA-35 (Murari Color Technology Institute M), calculate the color difference (ΔEab books) from the unirradiated one and use it as a measure of light resistance. And so. The smaller the value, the better the light resistance. The results are shown in Table 1 below.

C, 1, Food Black 2 2 parts diethylene glycol 15 parts polyethylene glycol 18 parts water
Sevenfold section 1-1'
- ri1211 I II--12,
7 (Comparative example) Methionine 0.59°9 (Example) Methionine 2.0 8.2 (Example) Methionine 5.0 5.8 (Example) Methionine? , 0 3.8 (Example) Cystine 5.0 6.1 (Example) Cystine salt 5.0 5.8 (Example) Cystine
5.0? , 1 (Example) Note...
Addition amount (X parts) H...Light resistance (ΔEab book) L2 As shown in Table 1, the IYFl light resistance of the recorded image recorded by the method of the present invention using the recording medium of the present invention is that of the comparative example. This is a significant improvement compared to the case of
Furthermore, the recorded 1+In image according to the present invention was clear with high resolution and no ink bleeding even when a water-based ink containing water-soluble dye 1 was used. still.

The color development properties were equally excellent in the Examples and Comparative Examples.

Example 2 Freeness (C, S, F,) 400 as raw pulp
mJ1 LBKP was used, and synthetic silica ([1 piece made of silica, Nymp Seal NS, specific surface area 16
0rrr2/g) to 30 tons b1 of pulp solid content:
%, cationic starch (CATO
F, manufactured by Tamako National Co., Ltd.) was added internally at 0.2 weight: 4% based on the solid content of the pulp, and paper was made into a paper having a weight of 70 g/m' using a TAPPI standard sheet former to obtain a base paper.

Next, using a solution having the following composition as a coating liquid, the base paper was coated using a size press apparatus so that the dry coating amount was 2.0 g/m' to obtain a recording medium of the present invention. Further, a recording medium of a comparative example was prepared by applying a coating liquid containing no amino acid at all in the same manner as above.

Polyvinyl alcohol (manufactured by Kuraray, PVAC3T)
tripartite amino acid
2 parts water
95 copies Inkjet recording was performed on the above recording medium using the following ink, and the light resistance and water resistance were evaluated in the same manner as in Example 1. The results are shown in Table 2.

C, 1, Direct Bra, Ri 146 2 parts glycerin 15 parts polyethylene glycol 15 parts water
70 part 2, J 2
Sho l Uni Rentai ΔEab end-a, e
(Comparative example) Sulfuric acid sorter 5.2 (Example) Chizai sulfuric acid soda 3.9 (Example) Sodium bisulfate
4.9 (Example)-I: Foot temperature 2 As shown in Table 1, the light resistance of images obtained by the method of the present invention using the recording medium of the present invention was significantly improved compared to that of the comparative example. It was something.

Example 3 The present invention was carried out in the same manner as in Example 1 except that 2 parts of cysteine was used as the amino acid in Example 1, and the substances in Table 3 below were used as the silica, and the results were as shown in Table 3 below. , in the case of silica with a specific surface area of loom2/g or more, the light resistance is at a good level and shows high color density,
It showed excellent color development.

No. 35-' Le Clear Recitation U Red Rabbit Z'' - Knee - Plate - 801
,057,1 100 1.31 7.2
265 1.40 7.4
340 1.54 7.3
500 1.57 7.5
Note 1... Color development (black color c degree O1
It is expressed as D. ) ■I...Light resistance (ΔEab book) Example 4 Instead of black dyeing 1 of the ink in Example 1, Direct Yellow 86 and Direct Blue 86 were used, respectively.
and Acid Red 35, yellow ink,
Cyan ink and magenta ink were prepared, and ink ciend recording was performed using these inks in the same manner as in Examples 1 to 3. As a result, almost the same excellent results as in Examples 1 to 3 were obtained.

Claims (5)

[Claims] (1) A recording medium characterized by containing both silica and an amino acid. (2) Silica has a specific surface area of 100 m^ by BET method.
2/g or more of synthetic fine particle silica. The recording medium according to claim (1). (3) A recording method characterized in that recording is performed on a recording medium containing both silica and amino acids using a recording liquid containing a water-soluble dye as a recording agent. (4) Silica has a specific surface area of 100 m^ by BET method.
2/g or more of synthetic fine particle silica. The recording method according to claim (3). (5) The recording method according to claim (3), wherein the water-soluble dye is at least one substance selected from direct dyes, acid dyes, and food colorings.