JPH04110360A - Recording fluid and recording therewith - Google Patents

Abstract

PURPOSE:To obtain a recording fluid which can give a recording of excellent quality on plain paper without blotting by adding iodine and a boron compound to a recording fluid containing a coloring material, a water-soluble organic solvent and water. CONSTITUTION:A recording fluid essentially consisting of a coloring material, a water-soluble organic solvent and water, wherein iodine and a boron compound (e.g. sodium borate or potassium borate) are contained. This fluid can give a nonblotting recording on noncoated papers such as ordinary copying paper, report paper, note or letter paper, the so-called plain papers.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a recording liquid and a recording method, and more specifically to copy paper, report paper, notebooks, stationery, and bond paper commonly used in offices and homes. The present invention relates to a recording liquid and a recording method capable of recording without bleeding on uncoated paper such as continuous slip paper, so-called plain paper.

(Prior art and its problems) A wide variety of compositions have been reported for inkjet recording liquids, and recording liquids consisting mainly of pigments or water-soluble dyes, water-soluble organic solvents, and water are used. is,
The same applies to recording liquids for other writing instruments.

When this type of recording liquid is used in an inkjet recording method and recorded on plain paper without a special ink-receiving layer, there is a common problem that bleeding occurs, although there are some differences depending on the composition. . Therefore, in order to suppress bleeding, a method has been proposed in which a high viscosity solvent is further added to the recording liquid. However, although bleeding can be suppressed by increasing the viscosity, this requires a considerable amount of high-viscosity organic solvent, which increases the viscosity of the recording liquid too much and reduces the ink ejection speed at the nozzle. In addition, there is a problem that discharge becomes unstable due to a decrease in surface tension.

Therefore, as an attempt to solve such problems, Japanese Patent Publication No. 60-500540 and Japanese Patent Application Laid-open No. 63-15948
Publication No. 5, etc. are disclosed.

However, in the above example, sufficient effects could not be obtained for a wide variety of plain papers.

Accordingly, an object of the present invention is to provide a recording liquid and a recording method that are excellent in various recording properties and can perform bleeding-free recording without excessively increasing the viscosity of the recording liquid.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, the present invention provides a recording liquid containing at least a coloring material, a water-soluble organic solvent, and water, which is characterized by containing iodine and a boron compound, and a recording material containing at least a small amount of the coloring material. In the recording method performed by applying a recording liquid containing a water-soluble organic solvent and water, the recording liquid of the present invention can be used in combination with the above-mentioned recording material 1. When attached to the recording material, the recording liquid forms a gel with the iodine and/or boron compounds in the recording liquid, even if the sizing agent is starch-based, polyvinyl alcohol-based, or a combination thereof. It has been found that bleeding can be effectively prevented.

It is easy to determine whether or not the recording material contains a starch-based and/or polyvinyl alcohol-based sizing agent, since it shows a blue coloration when the iodine solution used in the iodine-starch reaction is applied to the recording material. can be determined.

Unlike the case of adding a high viscosity solvent, the above-mentioned iodine and boron compounds can provide excellent effects with a small amount and do not adversely affect the viscosity or surface tension of the recording liquid. Further, since iodine reacts with the sizing agent to gel the sizing agent and develops a blue color, brown discoloration of recorded images is suppressed, and therefore it is particularly suitable for cyan and black recording liquids.

(Preferred Embodiment) A recording method characterized in that plain paper is sized with a ribinyl alcohol-based sizing agent, and the recording liquid contains iodine and a boron compound.

(Function) The inventors of the present invention have proposed a method for producing copy paper, report paper, notebooks, stationery, bond paper, etc., which are generally used in offices and homes.
As a result of studying the recording liquid composition that does not cause bleeding in so-called plain paper such as continuous slip paper, we found that in most cases, these so-called plain papers contain starch-based (in the present invention, starch, modified starch such as oxidized starch, etc.) ) and/or polyvinyl alcohol-based (in the present invention, a general term including various polyvinyl alcohols with different degrees of saponification and degree of polymerization, modified polyvinyl alcohols such as carboxylic acid-modified polyvinyl alcohol) sizing agents (rarely, these sizes Focusing on the fact that sizing agents are sometimes used as internal sizing agents, we focused on the fact that starch-based sizing agents and iodine, which have strong gel-forming ability, and polyvinyl alcohol-based sizing agents, which have strong gel-forming ability, are the next most preferred. The present invention will be explained in more detail by citing embodiments.

The iodine used in the present invention is generally considered to exist in the form of iodide ions, referred to as 3-, in the recording liquid.
The method of adding it to the recording liquid is not particularly limited, but a method of adding it as an alcohol solution, a method of adding it after solubilizing it in a warm KI solution, etc. can be used.

As the boron compound used in the present invention, borates such as sodium borate and potassium borate are mainly used, but functional organic boron compounds (trade name Hyboron MCB-300
Similar effects can be obtained with the following materials: (1) (manufactured by Boron International), etc., and they can be added directly to the recording liquid by dissolving them.

The appropriate amounts of iodine and boron compounds to be added are 0.01 to 10% by weight each in the total amount of the recording liquid, and the total amount of both is preferably 0.02 to 15% by weight. If the amount added is less than this range, the ability to gel the sizing agent will be insufficient, and if the amount exceeds the above range,
There is a risk of deterioration or precipitation of the dye in the recording liquid. A more preferable addition amount is 01 to 8% by weight in total.

The coloring materials constituting the recording liquid of the present invention include direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes,
Vat dyes, soluble architectural dyes, reactive disperse dyes, oil dyes,
Various pigments may be used, but among them, water-soluble dyes are particularly preferred in view of the performance of the recording liquid.

The content of these coloring materials is determined depending on the type of liquid medium components, the properties required of the recording liquid, etc., but in general, it is approximately 0.2 to 20% by weight in the total amount of the recording liquid. Preferably 0.
The proportion is 5 to 10%, more preferably 1 to 5%.

The recording liquid of the present invention is characterized by containing iodine and a boron compound together with a coloring material, but requires a liquid medium consisting of water and a general organic solvent used in conventionally known recording liquids. For example, organic solvents include lower alkyl ethers of polyhydric alcohols such as methyl alcohol, ethyl alcohol monomethyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) ether, and nitriethylene glycol dimethyl (or ethyl) ether. , lower dialkyl ethers of polyhydric alcohols such as tetraethylene glycol dimethyl (or ethyl) ether; sulfolane, N-methyl-2-pyrrolidone, ], ]3-dimethyl-2-imidazolidinone.

The content of the water-soluble organic solvent is generally 2% to 50% by weight, preferably 2% to 3% by weight based on the total weight of the recording liquid.
The range is 0%.

Although the media described in ``2'' can be used alone or as a mixture, the most preferable liquid medium composition is water and one or more organic solvents, with a small amount of the solvent (both 1 and 2) being water-soluble and high boiling point. It contains an organic solvent, for example, a polyhydric alcohol such as diethylene glycol, triethylene glycol, or glycerin.

The main components of the recording liquid of the present invention are as described above.
n-propyl alcohol, isopropyl alcohol, n
-butyl alcohol, 5eC-butyl alcohol, te
rt-butyl alcohol, isobutyl alcohol, n-
Alkyl alcohols having 1 to 5 carbon atoms such as pentanol; amides such as dimethylformamide and dimethylacetamide; ketone or keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; diethylene glycol and triethylene glycol , oxyethylene or oxypropylene addition polymers such as tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol, polypropylene glycol, ethylene glycol, propylene glycol, trimethylene glycol, butylene glycol, 12,6-hexanetriol, hexanetriol, etc. Alkylene glycols in which the alkylene group has 2 to 6 carbon atoms, such as xylene glycol; thiodiglycol, glycerin, ethylene glycol monomethyl (or ethyl) ether, diethylene, and various other dispersants, surfactants, and viscosity adjusters. Agents, surface tension regulators, optical brighteners, etc. can be added as necessary within the range that does not hinder the achievement of the objects of the present invention.

Examples include various cationic, anionic or nonionic surfactants, surface tension modifiers such as jetanolamine and triethanolamine; p+ (modifiers by buffers), antifungal agents, etc.

In addition, in order to prepare the recording liquid used in the type of inkjet recording method that charges the recording liquid, lithium chloride,
A resistivity adjuster such as inorganic salts such as ammonium chloride and sodium chloride is added.

The recording liquid of the present invention is suitable for recording with various writing instruments and pen plotters, but is particularly suitable for use in inkjet recording methods in which the recording liquid is ejected by a bubbling phenomenon of the recording liquid caused by thermal energy. It is suitable and has the characteristics that the discharge is extremely stable and no bleeding occurs. However, in this case, the thermal physical property value (
For example, specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted.

Furthermore, the recording liquid of the present invention solves the problem of bleeding of the recording liquid when recording on plain paper, etc., and at the same time improves matching with an inkjet head. is 30-68
dyne/cm, and the viscosity is desirably adjusted to 20 cP or less, preferably 10 cP or less, more preferably 5 cP or less.

Therefore, in order to adjust the recording liquid to the above-mentioned physical properties and more fully solve the problems with plain paper, the water content in the recording liquid of the present invention should be at least 10% by weight, preferably at least 30% by weight, and more preferably at least 30% by weight. is preferably contained in an amount of 50% by weight or more.

The recording method of the present invention is a recording method characterized by using the above-mentioned recording liquid and plain paper containing a hydroxyl group-containing sizing agent as a recording material. Although not particularly limited, a particularly preferred method is Ink 1.

(Example) Next, the present invention will be explained in more detail by giving examples and comparative examples. In the text, parts and percentages are based on weight unless otherwise specified.

Daiarashi Kaijonu After mixing the following ingredients and stirring for 5 hours, the pH was adjusted to 7.5 with an O1% aqueous solution of sodium hydroxide, and a membrane filter with a pore size of 0.22 μm (product name
Pressure filtration is carried out using a Fluorobor filter (manufactured by Judenenko),
Recording liquids of Examples 1 to 5 were obtained.

Next, using the obtained recording liquid, recording was performed using an inkjet printer BJ-130 (trade name: manufactured by Canon ■) that uses a heating element as an energy source for ejecting the recording liquid. The obtained recorded matter was evaluated.

The results are shown in Table 1. Evaluation is usually at 25℃ and 60%
I went to RH.

! It is an inferior Ujet method. The inkjet method may be any conventionally known method (although not particularly limited, in the present invention, for example, the method described in Japanese Patent Application Laid-Open No. 54-59936 is used, in which the recording liquid is heated by the action of thermal energy). Particularly useful is a method in which a rapid volume change is caused and the recording liquid is ejected from the nozzle by the force exerted by this state change.

The recording material used in the present invention is non-coated paper, so-called plain paper, such as copy paper, report paper, notebook, stationery, bond paper, and continuous slip paper, which are generally used in offices and homes, and polyvinyl alcohol. , starch, modified starch, and other starch-based sizing agents, and polyvinyl alcohol-based sizing agents.These plain papers do not bleed, and high-quality recording is possible.

The recording liquid of the present invention is suitable for recording on the above-mentioned plain paper, and can also be used for recording materials specially prepared for inkjet printing and other recording materials. Naturally C, 1, Direct Black 15
4 3-part diethylene glycol
15 parts 5% ethanol solution of iodine 8 parts sodium borate 05 parts water
74 parts Real 5 l λ C, 1, Food black 2 4 parts diethylene glycol 20 parts 5% ethanol solution of iodine 5 parts Sodium borate
0.3 parts water
70 parts Mitsudan C,1, Direct Blue 86 3 parts ethylene glycol 10 parts diethylene glycol 10 parts 5% ethanol solution of iodine 10 parts Functional organoboron compound (trade name)
Hiboron MCB-300 (manufactured by Boron International) 3 parts water
64 parts Examples 4-5 The following components were mixed and centrifuged (1200 rpm,
15 minutes) to remove coarse particles.
A recording liquid was obtained.

External side A Carbon black (MA, -100, manufactured by Mitsubishi Kasei ■)
3 parts Demol N (manufactured by Kao Soap ■, sodium salt of β-nafucrene sulfonic acid formalin condensate) 0.5 parts 20 parts 10 parts 2 parts 6 parts 1 part 58.5 parts Ethylene glycol diethyl glycol triethanolamine 5% ethanol solution of iodine Sodium borate water 1 u Carbon black (Color Black S-170, manufactured by Degussa) 3 parts Demol N (manufactured by Kao Soap ■, β-naphthalene Table 1 (bleeding potential) Table 1 After printing on the recording material, it was left to stand for more than 1 hour, and then bleeding and edge sharpness were evaluated based on the dot level.

○: Bleeding (edges are sharp).

△: Some bleeding is seen, and the edges are also slightly blurred.

×...There is a lot of blurring (and the edges are also blurred.

When the iodine solution was applied to each recording material, the results were as follows: Blue 1 (sodium salt of fluphonic acid formalin condensate) 0.5 parts ethylene glycol 2 parts diethylene glycol 10 parts triethanolamine 2 parts 5% ethanol solution of iodine 6 parts boric acid lithium
2 parts water
585 parts Comparative Example 1 A recording liquid of Comparative Example 1 was prepared in the same manner as in Example 1 except that sodium borate was not used.

Comparative Example 2 A recording liquid 2 of a comparative example was prepared in the same manner as in Example 1 except that iodine was not used.

(Hereinafter referred to as blank space) It exhibited a color and the presence of a sizing agent such as polyvinyl alcohol or starch was confirmed.

(Effects) As explained above, the recording liquid and recording method of the present invention can be applied to plain paper such as copy paper, report paper, notebook, stationery bond paper, continuous slip paper, etc., which are generally used in offices. This enables good recording with excellent quality and no bleeding.

Claims (3)

[Claims] (1) A recording liquid containing at least a coloring material, a water-soluble organic solvent, and water, which is characterized by containing iodine and a boron compound. (2) In a recording method in which a recording liquid containing at least a coloring material, a water-soluble organic solvent, and water is applied to a recording material, the recording material is sized with a starch-based and/or polyvinyl alcohol-based sizing agent. 1. A recording method, characterized in that the recording liquid is plain paper and the recording liquid contains iodine and a boron compound. (3) The recording method according to claim 2, wherein the recording method is an inkjet recording method.