JPH01299879A - Marking ink composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in resistance to drying of a penpoint, which means that it takes a long time before the pen gives a blurred writing even when it is left without its cap, by blending at least a colorant, an organic solvent and a specified polyethylene glycol fatty acid ester together. CONSTITUTION:This composition comprises at least a colorant which comprises a dye and/or a pigment, an organic solvent (e.g., n-propanol) and a polyethylene glycol fatty acid ester which is normally solid and has an HLB<=12 (e.g., monostearate of 2mol of polyoxyethylene having an HLB of 4.0). If necessary, additives such as a film-forming property imparting agent and a dispersant are suitably added to the above composition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a marking ink composition that has excellent pen nib drying resistance, and more specifically, the present invention relates to a marking ink composition that has excellent pen nib drying resistance, and more specifically, the pen nib remains stable even when left with the cap removed for a long period of time. This invention relates to a marking ink composition that is difficult to dry.

(Prior Art) Conventionally, marking ink compositions, that is, oil-based inks, have been used on absorbent surfaces such as paper, cloth, plastics, glass, etc.
It is widely used because it can be written on both non-absorbent surfaces such as metal, and it dries quickly. In addition, these inks range from common types that have strong handwriting fixation properties to those for writing boards that can erase handwriting written on a non-absorbing surface by light rubbing with a dry cloth, etc. by adding a release agent, etc. There is erasable ink.

(Problem to be Solved by the Invention) However, in any type of marking ink composition described above, when used in a writing instrument and left with the cap removed, the organic solvent evaporates and the colorant and resin The problem is that not only the surface of the pen nib but also the inside of the pen nib is clogged by precipitation, and ink cannot be ejected from the nib, resulting in blurred handwriting or even the inability to write.

The present invention aims to solve the above problems.

(Means for Solving the Problems) The present invention comprises a colorant, an organic solvent, a colorant that is solid at room temperature, and
The gist of the present invention is a marking ink composition comprising at least a polyethylene glycol fatty acid ester having an HLB of 12 or less.

Each component of the present invention will be explained in detail below.

The coloring agent used in the present invention is a dye or/and a pigment.

As the dye, general oil-soluble dyes or alcohol-soluble dyes that are soluble in organic solvents can be used, and as the pigment, there are no particular limitations as long as it can be stably dispersed in the ink composition. In particular, so-called processed pigments whose surfaces are coated with resin are preferred from the viewpoints of dispersibility, stability over time, and workability. These colorants can be used alone or in combination, and the amount used varies depending on the type of colorant and other ink components, but is 1 to 20% by weight based on the total amount of ink.
, preferably 2 to 17% by weight.

Examples of organic solvents include alcohols such as ethanol, propatool, isopropanol, butanol, ketones such as methyl ethyl ketone and methyl isobutyl ketone, esters such as ethyl acetate and butyl acetate, and aromatic carbonization such as benzene, toluene, and xylene. Examples include hydrogen, alicyclic hydrocarbons such as cyclohexane and ethylcyclohexane, aliphatic hydrocarbons such as hexane and heptane, cellosolves such as ethylene glycol monoethyl ether, and carbitols such as diethylene glycol monobutyl ether.
These can be used alone or in combination, and the amount used is 55 to 90% by weight based on the total amount of ink.
Preferably it is 65 to 85% by weight.

The gist of the present invention is solid at room temperature and HLB of 12.
The following polyethylene glycol fatty acid esters are used to prevent handwriting from fading when the cap is removed and left as is. For example, MMS-2 (stearic acid monoester containing 2 moles of polyoxyethylene).

HLB4.0), MYS-4 (4 moles of polyoxyethylene stearic acid monoester, HLB6.5), M
MS-10 (stearic acid monoester of polyoxyethylene 10 moles, HLBll, O)EGMS-70 (stearic acid monoester of ethylene glycol, HLB
3゜5), EGDS (stearic acid diester of ethylene glycol, HLB2.5), DGES (stearic acid monoester of diethylene glycol, HLB4)
．． 5), CDS-400 (stearic acid diester of polyethylene glycol, HLB8.5) (manufactured by Nikko Chemicals), Nonion S-2 (HLB8.0),
There is Nonion S-4 (HLBIl, 6) (polyoxyethylene monostearate, manufactured by NOF Corporation), and its usage amount is preferably 0.05 to 5% by weight based on the total amount of the ink.

When it is liquid at room temperature, it has little effect on pen tip drying resistance, and when HLB exceeds 12.

This is because the solubility in the above solvent is low and it is not possible to add it in an amount sufficient to provide good nib drying resistance.

In addition to the above components, general oil-based inks with fixing properties include a dispersant for imparting film-forming ability, imparting adhesion to the writing surface, and adjusting the viscosity of the ink, and in the case of using pigments as a coloring agent. Conventionally used natural resins and synthetic resins can be used for this purpose, including rosin, rosin ester, rosin-modified glycerin ester, rosin-modified maleic acid resin, rosin-modified phenolic resin, and rosin-modified phenol. Examples include rosin resins such as glycerin esters, cellulose resins such as ethyl cellulose and nitrocellulose, petroleum resins, ketone resins, polyvinyl butyral, vinyl chloride-vinyl acetate copolymers, etc., and the amount used is 1 to 10% based on the total amount of ink. 30% by weight is preferred.

In addition to the above-mentioned components, in addition to the above-mentioned components, in order to obtain an erasable ink for writing boards that can erase handwriting written on the non-absorbing surface by light rubbing with a dry cloth, the organic It is sufficient to add a release agent that has a lower vapor pressure than the solvent and is hardly volatile or non-volatile. Examples of release agents include higher fatty acid esters, higher aliphatic hydrocarbons, and polyoxyethylene alkyl ether type nonionic surfactants. and derivatives thereof, polyoxyethylene alkylphenol ether type nonionic surfactants and derivatives thereof, and these may be used alone or in combination.

Erasability can be imparted to handwriting, and the amount used should be 1 to 10% by weight based on the total amount of ink.

In addition to the above-mentioned components, various additives such as antiseptic/antifungal agents, antifoaming agents, etc. can be used as necessary.

In addition, the marking ink composition of the present invention contains, as a colorant,
When using a dye, it can be obtained by mixing and dissolving each component, and when using a pigment, it can be easily obtained by mixing and dispersing each component with a dispersion machine such as a homomixer, ball mill, or lab mixer. I can do it.

(Function) It is not clear why the marking ink composition of the present invention has excellent pen tip drying resistance and prevents blurring of handwriting, but it is speculated as follows.

Solid at room temperature and HLB of 12 used in the present invention
The following polyethylene glycol fatty acid ester precipitates at the same time when the organic solvent evaporates at the pen tip and the colorant and resin precipitates, preventing strong bonds between the colorant and resin and ensuring that a complete film is formed. In order to suppress this and form a very brittle film on the surface of the pen tip, it is believed that further evaporation of the organic solvent is prevented, and the film is torn by normal writing pressure, making it possible to write and prevent blurring.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples, and in the Examples, the term ``1 part'' indicates ``part by weight.''

Example 1 (Ink with fixing properties) Parifast Red 31808 (C, 1, acid red mixture, Orient Chemical Industry ■
7 parts Tamanol 1008
4 parts (oil-soluble phenol resin, manufactured by Arayo Kagaku Kogyo ■) Rosin WW
1 part (rosin resin, Tokushima essential oil) Ethanol 64 parts Ethyl cellosolve 20 parts Ethyl acetate
3 parts MYS - 41 parts A red ink was obtained by stirring the above components in a homomixer for 2 hours.

Example 2 (Ink with fixing properties) Neozapon Black RE (C, 1, Solvent Black 27, manufactured by BASF)
16 part rosin WW
10 Part n-Proper Tools
12 parts methyl cellosolve 60 parts M
MS-22 parts A black ink was obtained using the above ingredients in the same manner as in Example 1.

Example 3 (ink with peelability) Fuji As Black 8 parts (processed pigment, manufactured by Fuji Shiki ■) Ethanol 45 parts Isopropanol 34.4 parts MMS-102 parts Hexadecyl 2-ethylhexanoate 6.8 parts Emulgen 408 3.8 parts (polyoxyethylene oleyl ether, manufactured by Kao Soap ■) A black ink was obtained using the above ingredients in the same manner as in Example 1.

Example 4 (ink with peelability) Fuji IK Blue 7 parts (processed pigment, manufactured by Fuji Shiroki ■) Butyl acetate 30 parts Methyl ethyl ketone 43 parts Methyl isobutyl ketone 7 parts EGDS
2 parts n-butyl stearate 8 parts liquid paraffin 3 parts A blue ink was obtained using the above ingredients in the same manner as in Example 1.

Comparative Example 1 MMS-4 was removed from Example 1, and MYO-10 (
Polyoxyethylene 10, liquid at room temperature, HLBIl, O
Mol's oleic acid monoester, manufactured by Nikko Chemicals)
A red ink was obtained in the same manner as in Example 1 except that .

Comparative Example 2 MMS-2 was removed from Example 2, and MYS-25 (
Polyoxyethylene 25, solid at room temperature, HLB 15.0
A black ink was obtained in the same manner as in Example 1, except that mol of stearic acid monoester (manufactured by Nikko Chemicals ■) was added.

(The following is a blank space) (Effects) The marking ink compositions obtained in Examples 1 to 4 and Comparative Example 1.2 were used to conduct a pen nib drying resistance test, and the results are shown in the table.

Table <Nib drying resistance> (Comparative example 2 was not tested because MMS-25 was not completely dissolved.) (Note) Test method: ■ A fiber core was used as the nib and batting was used. Each marking ink composition was filled into the prepared writing instruments.

Remove the cap and leave it indoors (temperature 20°C, humidity 50%).

■Write down every 5 minutes for the first hour.

■ After one hour has passed, write every hour and measure the time until the handwriting becomes faint.

As described above, the marking ink composition of the present invention has excellent pen tip drying resistance when used in writing instruments, and the time required for handwriting to fade when the cap is removed and left unused is long, making it impractical. It is excellent.

Patent applicant: Pentel Co., Ltd.

Claims (1)

[Claims] A marking ink composition comprising at least a colorant, an organic solvent, and a polyethylene glycol fatty acid ester that is solid at room temperature and has an HLB of 12 or less.