JP3387288B2 - Oily metallic glossy ink for writing instruments - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-based metallic glossy ink for a writing instrument , which exhibits a sufficient metallic luster in handwriting even after being stored for a long period of time and has excellent gloss persistence. . [0002] A metallic glossy ink contains at least an aluminum powder pigment, a resin and an organic solvent. As organic solvents, aromatic hydrocarbons such as xylene and toluene have been frequently used because they are inexpensive and have high solubility in resins. Since the specific gravity of the aluminum powder pigment used in this ink is large, the pigment sediments during storage. Therefore, when using it for writing instruments, the ink is directly filled into the ink storage chamber of the writing instrument together with a stirring body (metal ball, etc.) for re-dispersion of the precipitated aluminum powder pigment, and the writing instrument is shaken before use.
The precipitated aluminum powder pigment was redispersed and used.
By the way, the aromatic hydrocarbon-based organic solvents conventionally used as described above have problems such as high odor and toxicity, and in recent years, alicyclic hydrocarbons such as methylcyclohexane and ethylcyclohexane with low odor and toxicity are used. Many proposals have been made to use hydrogen as a solvent for the ink. [0003] The metallic luster color ink described above has a problem that the metallic luster decreases after lapse of time or the color becomes dark due to discoloration. In addition, when an alicyclic hydrocarbon is used as a solvent, this solvent has poor solubility in a resin, and particularly when used in a writing instrument, ink is poorly printed, and after storage for a long period of time, blurring or writing occurs. However, there are many problems in that it may become impossible. [0004] The present invention provides an aluminum powder pigment of 10% by weight or more and 40% by weight or less based on the total amount of ink, and a phosphorus powder of 2% by weight or more and 50% by weight or less based on the total amount of the ink. Not less than 5% by weight based on the total weight of the ink with the trialkyl acrylate and / or dialkyl phthalate
At least comprising writing instrument oily metallic luster color ink from the upper 40% or less by weight of the phosphoric acid trialkyl ester and / or a resin that is soluble in an dialkyl phthalates in which the gist. The details will be described below. The aluminum powder pigment is used as a coloring material for imparting metallic luster to the handwriting, and its addition amount is 10 to 40 with respect to the total amount of the ink.
% By weight is preferred. When the addition amount is less than 10% by weight, the density in the case of handwriting tends to decrease, and when the addition amount is more than 40% by weight, the viscosity increases, and
Ink discharge tends to decrease. The resin is used for improving the dispersibility of the aluminum powder pigment, improving the glossiness of the handwriting, and improving the fixing property of the handwriting. Examples of resins that can be used include coumarone resin, xylene resin, phenol resin, and ketone resin.
It is preferred to add. When the amount is less than 5% by weight, the effect tends to be small, and when the amount is more than 40% by weight,
Increasing viscosity increases ink ejection from the pen tip.
In the direction. [0007] Trialkyl phosphates and dialkyl phthalates are used as solvents and are excellent solvents that dissolve the resin well and do not adversely affect the aluminum powder pigment such as deterioration or corrosion after aging. . Specifically, trimethyl phosphate, triethyl phosphate, trinormal propyl phosphate, triisopropyl phosphate, trinormal malbutyl phosphate, trinormal pentyl phosphate, trinormal hexyl phosphate, trinormal heptyl phosphate, phosphorus Trinormal octyl acid, tris (2-ethylhexyl) phosphate, dimethyl phthalate,
Diethyl phthalate, dinormal propyl phthalate, dinormal butyl phthalate, dinormal pentyl phthalate,
Examples include dihexyl phthalate, diheptyl phthalate, dioctyl phthalate, and di-2-ethylhexyl phthalate. These can be used alone or as a mixture of two or more, and the used amount can be 2 to 90% by weight based on the total amount of the ink.
It is preferable to add 2 to 50% by weight. In addition to trialkyl phosphate and dialkyl phthalate, esters such as butyl acetate, amyl acetate and ethyl acetate, methyl ethyl ketone, methyl Organic solvents such as ketones such as isobutyl ketone, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane and cyclopentane, and hydrocarbons such as normal heptane, normal octane and mineral spirit may be used in combination. Further, in addition to the above-mentioned components, if necessary, dyes or pigments are used for producing a color tone such as gold or copper, or preservatives conventionally used for inks for writing instruments, etc. Various additives such as an antifungal agent, a wetting agent, a drying inhibitor, a viscosity modifier, a freeze stabilizer, an antifoaming agent, and a surfactant can be appropriately selected and used. The oily metallic glossy ink for writing implements can be obtained by stirring and mixing the above components using a conventionally known stirrer and uniformly dissolving them. It is not clear why the oil-based metallic glossy ink for a writing instrument according to the present invention improves gloss persistence after aging, but it is presumed as follows. The causes of gloss deterioration and discoloration after aging include deterioration of the aluminum powder pigment itself, deterioration of the aluminum powder pigment due to the action of the resin, and deterioration of the gloss due to deterioration of only the resin in the ink. Many of the causes of the decrease in gloss are the interaction between the solvent and the aluminum powder pigment and the poor dissolution stability of the resin in the solvent. The trialkyl phosphate and the dialkyl phthalate used in the present invention have an effect of protecting the metal surface. Furthermore, for the solubility of the resin, carbonyl-based oxygen and ether-based oxygen in the solvent molecule are required, but trialkyl phosphate and dialkyl phthalate have this oxygen in the molecule. . That is, the trialkyl phosphate and the dialkyl phthalate protect the surface of the aluminum powder pigment, and in particular, have excellent gloss stability even after a lapse of time in that the resin has particularly excellent dissolution stability. It is. Example 1 Alpaste 240T (aluminum powder pigment, manufactured by Toyo Aluminum Co., Ltd.) 25 parts by weight Esculon V120 (coumarone-indene resin, manufactured by Nippon Steel Chemical Co., Ltd.) 30 parts by weight phosphoric acid Trinormal butyl 30 parts by weight Methylcyclohexane 15 parts by weight The above components were stirred with a stirrer for 4 hours to obtain a silver ink having metallic luster. Example 2 Alpaste 241M (aluminum powder pigment, manufactured by Toyo Aluminum Co., Ltd.) 20 parts by weight Esklon T120 (coumarone-indene resin, manufactured by Nippon Steel Chemical Co., Ltd.) 30 parts by weight Dibutyl phthalate 5 parts by weight Methylcyclohexane 45 parts by weight A silver ink having metallic luster was obtained in the same manner as in Example 1 using the above components. Example 3 Alpaste 241M (described above) 30 parts by weight Resin AP (ketone resin: manufactured by Huls) 30 parts by weight Trimethyl phosphate 20 parts by weight butyl acetate 20 parts by weight A shiny silver ink was obtained. Example 4 Alpaste 241M (described above) 35 parts by weight Ekslon V120 (described above) 20 parts by weight Dimethyl phthalate 25 parts by weight Methylcyclohexane 15 parts by weight Normal heptane 5 parts by weight A glossy silver ink was obtained. Example 5 Alpaste 241M (described above) 25 parts by weight Escron G90 (coumarone-indene resin, manufactured by Nittetsu Chemical Industry Co., Ltd.) 30 parts by weight Trinormal butyl phosphate 30 parts by weight Dibutyl phthalate 15 parts by weight The components were the same as in Example 1 to obtain a silver ink having metallic luster. Comparative Example 1 The procedure of Example 1 was repeated except that trinormal butyl phosphate was used and methylcyclohexane was added in the same amount.
In the same manner as in the above, a silver ink having metallic luster was obtained. Comparative Example 2 A silver ink having a metallic luster was obtained in the same manner as in Example 2 except that dibutyl phthalate was added and methylcyclohexane was added in that amount. Comparative Example 3 A silver ink having a metallic luster was obtained in the same manner as in Example 3, except that trimethyl phosphate was removed and butyl acetate was added in the same amount. Examples 1 to 5 and Comparative Examples 1 to 3 were obtained.
The oily metallic glossy ink for writing implements is a commercially available writing implement structure (Pentel White 100W, pen point: fiber core, valve structure with direct filling of ink into the barrel, filling with stirring ink and ball for stirring. , Pentel Co., Ltd.) to prepare a writing instrument for testing. The writing implement for this test was stored in a thermo-hygrostat at a temperature of 50 ° C. and a humidity of 30% for 6 months, and then written on a glass plate, and the handwriting before and after the storage was observed. Table 1 shows the results. [Table 1] Evaluation of gloss ○: glossy (no change) Δ: slight gloss (slightly reduced gloss) ×: no gloss (significant change) Evaluation of discoloration ○: no discoloration ×: discoloration is present. As described in detail above, the present invention relates to the present invention.
The oily metallic glossy ink for writing implements is an ink having excellent properties that gloss is maintained in handwriting even after long-term storage, and that discoloration does not occur.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-120368 (JP, A) JP-A-3-74472 (JP, A) JP-A-1-129070 (JP, A) JP-A-4- 7368 (JP, A) JP-A-6-299114 (JP, A) JP-A-4-126782 (JP, A) JP-A-55-158202 (JP, A) JP-A-58-1765 (JP, A) JP-A-6-192610 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 11/00-11/20 C09C 1/00-3/12

Claims (1)

(57) [Claims 1] 10% by weight or more and 40 % by weight based on the total amount of ink
Weight percent or less of aluminum powder pigment, 2 to 50 weight% of trialkyl phosphate and / or dialkyl phthalate to total weight of ink, and 5 to 40 weight% of total weight of ink And a resin soluble in the above trialkyl phosphate and / or dialkyl phthalate.