JPH0583106B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention allows writing on a writing board commonly known as a whiteboard, on which markings can be written using marking ink, and when the writing is no longer necessary, the writing can be erased. This invention relates to improvements in marking ink for writing boards that enable writing and erasing. (Prior art) In addition to colorants, resins, and solvents, conventional marking inks for writing boards of this type contain higher fatty acid esters, polyethylene glycol, and nonionic surfactants as release agents to facilitate erasing. etc. were added. (Problems to be Solved by the Invention) Characters, figures, etc. written on the writing board using such writing board marking ink can be removed by wiping the writing board with a dry cloth etc. by adding the above-mentioned release agent. Although erasing is possible, if a long period of time has passed after writing, it cannot be completely wiped off and the letters, figures, etc. that should be erased may remain faintly, making it impossible to completely erase them. (Object of the Invention) The present invention is intended to solve the problems of the conventional marking ink for writing boards, and it is possible to use the marking ink on the writing board not only immediately after writing but also after a long period of time. The purpose is to provide a marking ink for a writing board that can be completely erased. (Means for solving the problems) The present invention is intended to achieve the above-mentioned objects,
The method is to add one substance selected from carboxylated polyoxyethylene alkyl ethers and their derivatives represented by the following general formula as one of the additives to the ink whose main components are colorants, resins, and solvents. This is done using a writing board marking ink. General formula R-O-(CH ₂ CH ₂ O) _o CH ₂ COOM (R is a C ₄ to _{C 18} alkyl group, n is an integer of 1 to 20, M is an H atom or a metal atom such as Na or K, or Indicates ammonium or alkanolamine) (Examples of the invention) Next, examples of the invention will be described below. This marking ink for writing boards has a colorant, a resin, and a solvent as its main components, and as one of the additives, one substance selected from carboxylated polyoxyethylene alkyl ether and its derivatives, and as other additives. higher fatty acid ester,
It is made by blending polyethylene glycol, nonionic surfactants, etc. The colorant used is 1 to 15% pigment including processed pigments, and the resin used is vinyl, cellulose, vinyl chloride-vinyl acetate copolymer, etc.
%, a volatile solvent such as alcohol, ketone, or ester is used as the solvent, and 40 to 90% is selected from carboxylated polyoxyethylene alkyl ether and its derivatives as one of the additives. These substances are mixed at a ratio of 0.05 to 10% and other additives at a ratio of 0 to 20%. When carboxylated polyoxyethylene alkyl ether and its derivatives are added in small amounts, the molecules of this substance are oriented on the entire surface of the board in the areas marked with marking ink for writing boards, thereby modifying the surface and erasing it. It improves the performance. In that case, it is important that the surfactant used as a modifier is carboxylated. For example, if the surfactant is ethylene oxide with a free terminal, it will be more sensitive to the low-volatile solvents and resins used in this ink. It is ineffective because its solubility or affinity is too high and its orientation force is too weak. On the other hand, the phosphoric acid type, sulfonic acid type, and sulfuric acid type have low solubility and are less effective. Although it is possible to change this balance by changing the length of the alkyl group or ethylene oxide, it is not very effective, and carboxylic acid type seems to be particularly effective. As a formulation example of this example, the first formulation example and the second formulation example are
The marking ink for writing boards of the formulation example was prepared, and the marking inks for writing boards of the first conventional example and the second conventional example were tested for erasability after a long period of time on three types of writing boards. I went there. The first formulation example includes 3 parts of carbon black as a coloring agent, 5 parts of a vinyl chloride-vinyl acetate copolymer, and carboxylated polyoxyethylene as a substance selected from carboxylated polyoxyethylene alkyl ethers and derivatives thereof. Two parts of triethanolamine salt of octyl ether, 7 parts of dibutyl sebacate as other additives, 2 parts of polyoxyethylene alkyl phenyl ether, and 80 parts of MIBK as a solvent were used. The second formulation example includes 3 parts of phthalocyanine blue as a coloring agent, 4 parts of PVB as a resin, and 2 parts of ammonium salt of carboxylated polyoxyethylene lauryl ether as one substance selected from carboxylated polyoxyethylene alkyl ether and its derivatives. 8 parts butyl stearate as other additives, 83 parts ethanol as solvent
part was used. The first conventional example uses 3 parts of carbon black as a coloring agent, 5 parts of a vinyl chloride-vinyl acetate copolymer as a resin, 10 parts of cetyl caprate as an additive, and 10 parts of a solvent as a solvent.
82 parts of MIBK are used. In the second conventional example, 3 parts of phthalocyanine blue as a coloring agent, 4 parts of PVB as a resin, 8 parts of butyl stearate and 2 parts of polyoxyethylene alkyl ether as additives, and 83 parts of ethanol as a solvent are used. Three types of writing boards in each of the above formulations, namely A
The erasability of the plates, B plates, and C plates was as follows. However, it is expressed as 〇; good △; somewhat poor ×; poor.

[Table] (Effects of the Invention) As described above, the present invention provides an ink containing a colorant and a resin as a main component, in which one of the additives is selected from carboxylated polyoxyethylene alkyl ethers and derivatives thereof. By adding one substance, the molecules of this substance are oriented on the entire surface of the writing board marked with the writing board marking ink. Therefore, surface modification is performed, erasability is improved, and good erasing can be performed even after a long period of time has passed. Therefore, there is no need to wipe the writing board again with a wet cloth to completely erase incomplete erasure caused by the lapse of a long period of time, as in the past, and the writing board can always be kept in a beautiful condition. It is.

Claims (1)

[Scope of Claims] 1. One additive selected from carboxylated polyoxyethylene alkyl ethers and their derivatives represented by the following general formula for ink containing colorants, resins, and solvents as main components. A marking ink for writing boards characterized by the addition of a substance. General formula R-O-(CH ₂ CH ₂ O) _o CH ₂ COOM (R is a C ₄ to _{C 18} alkyl group, n is an integer of 1 to 20, M is an H atom or a metal atom such as Na or K, or (indicates ammonium or alkanolamine)