JPS5991161A - Metallic flake pigment ink for writing utensil - Google Patents

Abstract

PURPOSE:To provide the titled ink which can be prevented from leaking out of the joint (e.g. a gap between the front and the rear barrels) of writing utensils, by incorporating a fatty acid amide thixotropic agent. CONSTITUTION:10-40wt% metallic pigment such as aluminum flake, copper flake or colored metallic flake, 5-50wt% resin such as gum rosin, alkyd resin or phenolic resin, 30-80wt% org. solvent such as toluene, ethyl acetate or ethylene glycol monomethyl ether and 0.02-5wt% fatty acid amide thixotropic agent such as Tarlene 6,200 (a product of Kyoei Yushi Kagaku Kogyo K.K.) are mixed together.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal powder pigment ink for writing instruments that prevents ink leakage from the joints of parts such as the front and rear shafts of writing instruments, particularly ink leakage that occurs during temperature changes. .

Writing instrument O, which traditionally uses pigment ink, is the first
As shown in the figure and Fig. 2, a bottomed aluminum rear shaft 1, m
The front shaft 3 that holds the raising body 2 is connected to the valve set 8 consisting of a valve body 4, a bullet body 5, a finger-made valve recess 6, and a resin catch seat 7.
After filling with ink, they are joined by screwing or caulking.

When a temperature change occurs, due to the difference in expansion coefficient between resin and aluminum, a slight gap is created at the joint between the rear shaft 1 and the catch seat 7.
Ink flows out from the gap.

As a result, ink leaks easily from the joint between the front shaft and the rear shaft. However, since the particle size of the pigment in general pigment inks is small, the pigment tends to enter and fill the gaps, thereby preventing ink leakage. On the other hand, metal powder pigment ink has a problem in that since the particle size of the pigment is large, the pigment cannot enter the gap, resulting in ink leakage.

Therefore, the inventors of the present invention have conducted extensive research.

By focusing on the fluidity of the ink and adding a fatty acid amide-based thixotropic agent, we have created an ink that can prevent ink leakage from the joint between the front and rear shafts as much as possible without affecting the ink discharge properties. The present invention has been completed by discovering that it can be obtained. That is, the gist of the present invention is a metal powder pigment ink for writing instruments, which comprises at least a metal powder pigment, a fatty acid amide type chikuntropic agent, a resin, and an organic solvent.

Although it is not clear why the ink of the present invention prevents ink leakage as much as possible, it is speculated as follows.

The fatty acid amide thixotropic agent used in the ink of the present invention increases the thixotropy of the ink, and as a result, the fluidity of the ink decreases in areas other than the pen tip area during writing, where stress is applied to the ink. The fluidity of the ink is also reduced, and as a result, it is thought that ink leakage from small gaps in the joints that occurs when the temperature changes can be prevented as much as possible. 9. Even when the fatty acid amide thixotropic agent used in the present invention is used in a general pigment ink, the thixotropy of the ink is increased in the same way as in the present invention, but as explained earlier, when a metal powder pigment is used, This is particularly effective in preventing ink leakage.

Each component of the present invention will be explained in detail below.
There are brass powders, aluminum powders, copper powders, colored metal powders, etc., and the appropriate amount to be used is lr + 10 to 40 times the total amount of ink.

Fatty acid amide-based thixotropic agents are particularly important in the present invention and are used to impart thixotropy to the ink of the present invention and adjust the fluidity of the ink.A specific example thereof is Taref 6200-20. ．． tarvy7
000A,, Taref 7200-20. 7 Low/7 5A-1000゜Flownon 5P-10'OO
(all manufactured by Kyoeisha Yushi Kagaku Kogyo ■), etc. These can be used alone or in combination, and the amount used is preferably 0.02 to 5% by weight based on the total amount of the ink.

If the amount is less than 2% by weight, no sufficient effect will be obtained, and if it is more than 5% by weight, no further effect will be obtained, and the viscosity of the ink may increase, resulting in blurred handwriting.

Resin is used to improve the fixation of handwriting and to adjust the viscosity of ink, and various types of resins can be used as long as they are soluble in organic solvents. Examples include: Gum rosin, maleic acid modified rosin, alkyd resin.

Kent resin, xylene resin 1 petroleum resin, acrylic resin,
There are terpene resins, phenol resins, etc., and these can be used alone or in combination. The amount used varies depending on the type of resin, degree of polymerization, etc., but is preferably 5 to 50% by weight based on the total amount of the ink. If it is less than 5% by weight, the adhesion of handwriting to the surface to be written will not be sufficient, and if it is more than 50% by weight, the ink viscosity will increase, making it easy to cause blurred brush marks and clogging of the pen tip. .

The organic solvent can be selected as appropriate depending on the material used for the writing surface and other materials used for □, but specific examples include:
Aromatic solvents such as toluene and xylene, ethyl acetate,
Ester solvents such as butyl acetate and amyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone.

Examples include aliphatic hydrocarbon solvents such as cyclohexane and n-heptane, alcohol solvents such as ethyl alcohol, propyl alcohol, and n-butyl alcohol, and glycol ether solvents such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.

These can be used alone or in combination.

The amount used is preferably 30 to 80% by weight based on the total amount of ink.

In addition to the above ingredients, various dispersants may be added as necessary to improve the dispersion of the metal powder pigment, or known pigments for complementary colors, or additives such as dyes and other rust preventives may be used as appropriate. You can also do that.

Next, the method for manufacturing the ink of the present invention will be briefly described.

It can be easily obtained by mixing the above-mentioned components in the required amounts (adding a dispersant and other additives as necessary) and stirring.

Hereinafter, the present invention will be explained in more detail with reference to Examples, in which "1 part" indicates "part by weight".

Example 1 Gold powder, M 70 n O (brass powder pigment, manufactured by Fukuda Metal Foil & Powder Industry ■) 30.0 parts Talene 6200-20 (fatty acid amide thixotropic agent, manufactured by Kyoeisha Yushi Kagaku Kogyo ■) 2.0 parts None Ronal xylene resin 0 J 20 (xylene resin.

Matsushita Electric Works Co., Ltd. 30.0 parts Xylene 38.0 parts The above components were mixed and stirred at room temperature to obtain a golden ink.

Comparative example 1 Among the components of Example 1, Talene 6200-20 was excluded.

A golden ink was obtained in the same manner as in Example 1 except that xylene was added in the same amount.

Example 2 Alpace) 240T (aluminum powder pigment, manufactured by Toyo Aluminum) 20.0 parts Flow/yS P-1000 (fatty acid amide thixotropic agent, manufactured by Kyoeisha Yushi Kagaku Kogyo ■) 01 parts Tamanol 1008 (phenol resin).

Arayo Kagaku Kogyo Co., Ltd. 25.0 parts Butyl acetate 600 parts n-Hebutane 24.9 parts A silver ink was obtained using the above ingredients in the same manner as in Example 1.

Comparative Example 2 Fluonone 5P-1000 in the ingredients of Example 2 was 00
A silver ink was obtained in the same manner as in Example 2, except that n-hebutane was added by the reduced amount.

Example 6 Copper powder! IT, 3 (copper powder pigment, Fukuda Metal Foil Powder Industry (stock company))
25050 parts Tarentz 200-2 fatty acid amide thixotropic agent, Kyoeisha Yushi Kagaku Kogyo @Jn
) 3.0 parts Nisseki Neopolymer 120 (petroleum resin 1 Nippon Oil ■) 20.0 parts n-butyl alcohol
10.0 parts ethylene glycol monomethyl ether 10.0 parts toluene
32.0 parts A copper colored ink was obtained using the same ingredients as in Example 1.

1-j- Among the components of Example 3, Talene 7200-20 was excluded.

A copper colored ink was obtained in the same manner as in Example 3 except that toluene was added in the same amount.

Above are Examples 1 to 3. Table 1 shows the results of the ink leakage test for the inks obtained in Comparative Examples 1 to 3.

Table-1 * Ink leakage test examples 1 to 3. A commercially available valve type writing instrument (see Figure 1) was filled with the ink obtained in Comparative Examples 1 to 3, 20 samples each (120 samples in total), and after capping, the pen tip was turned downward and subjected to a cooling/heating cycle. (Leave it in a constant temperature and humidity room at 50 degrees Celsius for 5 hours, then leave it in a refrigerator at 0 degrees Celsius for 5 hours).
After repeating this process several times, we checked the number of ink leaks from the joint between the front and rear axles.

As shown above, the ink of the present invention is an excellent metal powder pigment ink for writing instruments that prevents as much as possible ink leakage from the joint between the front and rear shafts of the writing instrument, which tends to occur when the temperature changes.

[Brief explanation of the drawing]

FIGS. 1 and 2 are longitudinal cross-sectional views of essential parts of the valve-type writing instrument. 1... Outer axis 2... Cursive 3
...Front shaft 4...Valve body 5...
...Propellant 6...Valve seat 7...
...Socket 8...Valve set patent applicant
Pentel Co., Ltd. = 11- 4IIm Figure 2

Claims (1)

[Claims] A metal powder pigment ink for writing instruments is made of at least a metal powder pigment, a fatty acid amide type thixotropic agent, a resin, and an organic solvent.