JP3354854B2 - Correction fluid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a correction liquid, and more particularly to a handwriting with an aqueous ink such as an aqueous plapen, a felt pen, a ballpoint pen, an oily ink such as an oily ballpoint pen, an oily marking pen, and a PPC.
The present invention relates to a correction liquid for concealing and correcting a copy image by a copying machine or a CPC copying machine.

[0002]

2. Description of the Related Art Conventionally, correction fluids commercially available include white pigments for correcting and concealing typographical errors and dirt on paper, resins as binders for white pigments, solvents for dissolving the resins, and white pigments. It is composed mainly of a dispersant for dispersing the pigment well.

[0003]

As such a conventional correction liquid, an oily correction liquid must be selected and used for handwriting with water-based ink, and an aqueous correction liquid must be selected for handwriting with oil-based ink. If the above relationship is incorrect, the dyes and pigments constituting the handwriting ooze out, making it difficult to sufficiently cover and correct. As a method for solving such a problem, a naphthenic hydrocarbon solvent which does not cause bleeding in both handwriting with an aqueous ink and handwriting with an oil-based ink is used as a solvent.

The use of the above naphthenic hydrocarbon solvents as a solvent for correction fluids is disclosed, for example, in JP-A-59-597.
No. 54 and Japanese Unexamined Patent Publication (Kokai) No. 3-168252, etc., also disclose resins dispersing a white pigment used in a correction fluid. However, when these resins are used, the dispersion stability of the white pigment is reduced. And those satisfying the properties of the coating film formed from the correction liquid have not yet been obtained.

Accordingly, it is an object of the present invention to conceal and correct handwriting with water-based ink, handwriting with oil-based ink, and a copied image with one type of correction liquid regardless of the type of ink. Excellent physical properties of coating film formed from liquid,
Another object of the present invention is to provide a correction liquid having a good dispersion stability of a white pigment even for long-term storage.

[0006]

The above object is achieved by the present invention described below. That is, the present invention comprises a white pigment, an organic solvent containing a naphthenic hydrocarbon solvent, and an acrylic resin, wherein the acrylic resin comprises the following monomer (I):
A copolymer comprising (II) and (III), wherein the monomer unit (I) in the copolymer is 80 to 99.7% by weight;
The correction liquid is characterized in that the monomer unit (II) is 0.2 to 20% by weight and the monomer unit (III) is 0.1 to 5% by weight.

[0007]

In the above formula, R ¹ is a hydrogen atom or a methyl group; R ² is a linear or branched alkyl group having 3 to 18 carbon atoms or a hydrocarbon group containing a naphthene ring or an aromatic ring;
³ -C ₂ H ₄ - group, -CH = CH- group, - phenylene -
Or a -cyclohexylene- group. )

According to the present invention, the copolymer used in the present invention has sufficient solubility in a naphthenic hydrocarbon solvent for a correction fluid and is excellent in dispersibility of a white pigment. Both handwriting with ink and handwriting with oil-based ink, and even copied images, can be sufficiently concealed and corrected with one type of correction liquid without bleeding these handwritings and images. And a correction liquid having excellent white pigment dispersion stability even when stored for a long period of time.

[0010]

Next, the present invention will be described more specifically with reference to preferred embodiments. Specific examples of the monomer (I) constituting the copolymer which mainly characterizes the present invention include, for example, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and t-butyl methacrylate. 2-ethylhexyl methacrylate, lauryl methacrylate, alkyl methacrylate (C = 12, 13), dodecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, propyl acrylate, isopropyl acrylate, n-acrylate Butyl,
Isobutyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, alkyl acrylate (C = 12, 13), dodecyl acrylate, stearyl acrylate, cyclohexyl acrylate, benzyl acrylate, and the like. .

These monomers (I) can be used alone or in a mixture. Particularly preferred monomers are methacrylic esters in which R ¹ is a methyl group in the above formula (I). The content of these monomer units (I) in the copolymer used in the present invention is in the range occupying 80 to 99.7% by weight in the obtained copolymer.
When the content of the monomer unit (I) is less than 80% by weight, the viscosity of the correction liquid becomes high when the correction liquid is prepared, which is not practical. On the other hand, when the content exceeds 99.7% by weight. When the correction liquid is prepared, there is a problem in that the adsorbing power of the copolymer to the white pigment is weak, and the sedimentation of the white pigment in the correction liquid is increased. A particularly preferred range is about 90-99.7% by weight.

As the monomer (II) constituting the copolymer, specifically, 2-methacryloyloxyethyl succinate, 2-methacryloyloxyethyl maleate,
Acid-containing acrylates such as 2-methacryloyloxyethyl phthalate and 2-methacryloyloxyethyl hexahydrophthalate, 2-acryloyloxyethyl succinate, 2-acryloyloxyethyl maleate, 2-acryloyloxyethyl phthalate, hexa Examples thereof include carboxyl group-containing (meth) acrylates such as 2-acryloyloxyethyl hydrophthalate. These monomers can be used alone or in a mixture. Particularly preferred monomer (II) is R ¹ in the above general formula (II).
Is a methacrylic acid ester which is a methyl group. The content of these monomer units (II) in the copolymer used in the present invention is 0.2 to 0.2 in the obtained copolymer.
The range occupies 20% by weight.

When the content of the monomer unit (II) is less than 0.2% by weight, there is a problem that the adsorbability of the copolymer to the white pigment is weak, and the dispersion of the white pigment becomes poor. On the other hand, if the content exceeds 20% by weight, there is a problem in that the obtained correction fluid thickens and the stability of the correction fluid is impaired. A particularly preferred range is from about 0.2 to 10% by weight.
It is.

By using the above-mentioned monomer (II), a carboxyl group is introduced into the obtained copolymer, which keeps a good solubility in a naphthenic hydrocarbon solvent and, at the same time, a white pigment in the correction liquid. Is sufficiently adsorbed, the dispersion stability of the white pigment is improved, and the white pigment does not settle in the correction liquid for a long time, so that a correction liquid having excellent long-term dispersion stability can be obtained.

The monomer (III) constituting the copolymer
Specific examples thereof include glycidyl methacrylate and glycidyl acrylate. These monomers (III) can be used alone or in a mixture. Particularly preferred monomer (III) is glycidyl methacrylate in which R ¹ is a methyl group in the above general formula (III).

The content of these monomer units (III) in the above copolymer is 0.1% in the obtained copolymer.
-5% by weight. The monomer (III) is used when the monomers (I) to (III) are copolymerized.
The glycidyl group of (I) reacts with the carboxyl group of the monomer (II) to partially crosslink the obtained copolymer, and is suitable for the correction liquid when the obtained copolymer is dissolved in the solvent of the correction liquid. Demonstrates the effect of giving high viscosity.

When the content of the monomer unit (III) is 0.1
When the amount is less than% by weight, the obtained copolymer is insufficiently crosslinked, has a low viscosity when dissolved in the solvent of the correction liquid, and causes precipitation of a white pigment. On the other hand, when the content exceeds 5% by weight, the crosslink density of the obtained copolymer becomes too high,
It is not preferable because the viscosity becomes too high when dissolved in the solvent of the correction fluid. A particularly preferred range is from about 0.1 to 5% by weight.
It is.

The copolymer used in the present invention is polymerized by using the above-mentioned monomers (I) to (III) as essential components. Can be copolymerized. The above copolymer has sufficient solubility in a naphthenic hydrocarbon solvent described below, which is a solvent for the correction liquid, and adsorbs a white pigment well, thereby improving the dispersion.

The method of copolymerizing the monomers may be any of the conventionally known polymerization methods, but the preferred polymerization method is a method of copolymerizing in a suitable organic solvent. A particularly preferable method is a method in which the polymerization is carried out in a naphthenic hydrocarbon solvent constituting a solvent for the correction liquid described below. According to this method, the polymerization liquid can be used as it is as a resin solution of the correction liquid.

The above-mentioned copolymerization is carried out, for example, by polymerizing at a temperature of about 70 to 90 ° C. for about 7 to 8 hours using an appropriate amount of a known radical polymerization initiator to obtain a desired polymerization solution. The concentration of the polymer in the obtained polymerization solution is not particularly limited, and may be a dilute state or a concentrated state, and the concentration and viscosity of the polymerization solution may be adjusted by removing or adding a solvent in the final or correction liquid state. Good. Of course, the polymerization solvent is not limited to a naphthenic hydrocarbon solvent, and polymerization may be performed using another solvent to separate the polymer, and the polymer may be used for the correction fluid of the present invention.

Since the white pigment used in the present invention is required to have a high concealing property, it is preferable to contain 90% or more of various commercially available titanium oxide pigments. In addition, it is desirable to use in consideration of various physical properties such as gloss, smoothness, rewriting property, and sedimentation stability of the coating film surface formed from the correction liquid. As the titanium oxide, any of rutile type and anatase type can be used.
-550, R-690, R-780, R-820 (all manufactured by Ishihara Sangyo), Kronos KR-380, KR-480,
KA-20 (all made of titanium industry), Thai Pure R-9
00, R-921 and R-931 (all manufactured by DuPont).

The naphthenic hydrocarbon solvent used as a solvent for the correction fluid in the present invention is an organic solvent which is difficult to dissolve oily or aqueous handwriting or copy-copy image, and the preferred naphthenic hydrocarbon solvent has a boiling point of 70%.ヘ キ サ ン 130 ° C., specifically, cyclohexane having a low solvent odor,
Methylcyclohexane, ethylcyclohexane or a mixture thereof is preferably used. These naphthenic hydrocarbon solvents may be used in combination with another organic solvent of 50% by weight or less of the total amount of the solvent.

The correction fluids of the present invention is obtained by above-described copolymers and the white pigment is dissolved and dispersed in the naphthenic hydrocarbon solvent. The disperser to be used is not particularly limited, and a media disperser or a ball mill using glass, zircon, or the like can be used. Further, a solvent and other additives are added to the obtained dispersion, or the solvent is evaporated to adjust the viscosity to an appropriate value to finally obtain the correction liquid of the present invention.

The final composition of the correction fluid of the present invention is as follows:
When the entire correction liquid is 100 parts by weight, the copolymer is about 5 to 30 parts by weight, the white pigment is about 40 to 65 parts by weight,
The naphthenic hydrocarbon solvent is in a range of about 20 to 50 parts by weight, and the viscosity of the final correction liquid is about 20 to 50 parts by weight.
It is preferably in the range of 80 cps.

In addition to the above-mentioned components, various types of resins such as petroleum resins, various surfactants, and thickeners may be used in the correction fluid of the present invention in order to improve the physical properties of a coating film formed from the correction fluid. May be added, or a small amount of a coloring pigment such as carbon black may be added to match the color tone with the writing surface of paper or the like. In particular, petroleum resin is added in an amount of 0
When used together in an amount of from 40 to 40 parts by weight, preferably from 1 to 30 parts by weight, the tackiness of the coating film caused by drying the correction fluid can be eliminated.

[0026]

EXAMPLES Next, the present invention will be described more specifically with reference to Reference Examples, Examples and Comparative Examples. In the following, "parts" and "%" are based on weight unless otherwise specified. Reference Examples 1 to 5 500 ml of a mixture of the formulations described in Table 1 below having a stirrer, a nitrogen gas inlet, a thermometer and a reflux condenser.
Into a reaction vessel at 80 ° C. in a stream of nitrogen gas.
Polymerization was carried out while stirring for hours to obtain a copolymer solution shown in Table 1 below.

[0027] The numerical value of each component in Table 1 is the number of copies.

The yield Example 4 and Comparative Example 1 under Symbol Table 2 present invention and comparative examples of the correction fluid formulation was dispersed for 30 minutes by a paint shaker according to.

[0029]

The amounts in the tables are parts. The copolymer solution is a solution having a solid content of 50%. The petroleum resin solution is a 40% solids methylcyclohexane solution. The white pigment is manufactured by Ishihara Sangyo, and the petroleum resin is manufactured by Tosoh Corporation. Each of the correction liquids of the present invention and the comparative examples obtained as described above was evaluated by the following methods, and the results shown in Table 3 were obtained.

Evaluation method: viscosity: EL rotational viscometer: measured at 25 ° C., 5 rpm. Storage stability: Enclosed and sealed in a 50 cc glass bottle,
The viscosity of the sample after storage at 60 ° C. for 1 month was measured. Redispersibility: The sample after being stored at 60 ° C. for one month was lightly shaken 10 times.

Dispersibility: The particle size distribution of the pigment in the sample after storage at 60 ° C. for one month is measured, and those that are almost the same as the original dispersion are ○; Those were marked as x. Concealment: Colored evenly on plain paper (for PPC) with bar coater # 20, compared with general commercial products,
Equivalents were evaluated as ○, higher ones as ◎, and lower ones as X. Drying property: When compared with a commercial product, a substance having almost no difference was evaluated as ○, and a substance having a slower rate was evaluated as ×. Adhesion: Bar coater # 20 on plain paper (for PPC)
And the cellophane tape was peeled off, and the film which did not transfer the coating film to the tape side was evaluated as ○, the one which slightly migrated was evaluated as Δ, and the one which migrated was evaluated as ×.

Flexibility: Bar coater # 20 on plain paper (for PPC)
And the film was bent at 180 °, and the film which did not peel or crack was evaluated as ○, the film which cracked was evaluated as Δ, and the film which peeled was evaluated as ×. Blocking resistance: Two sheets of plain paper (for PPC) that were developed with a bar coater # 20 were bonded and pressed together. What peeled was evaluated as x. Rewriting: Bar coater # 2 on plain paper (for PPC)
0 was applied, and a water-based ballpoint pen and an oil-based ballpoint pen were used to write on it.

[0034] As is clear from Table 3 above, the correction liquid of the present invention is particularly excellent in storage stability, redispersibility of white pigment, concealing property and the like.

[0035]

According to the present invention as described above, the copolymer used in the present invention has sufficient solubility in a naphthenic hydrocarbon solvent for a correction fluid and has excellent dispersibility of a white pigment. It is possible to conceal and correct handwriting with water-based ink, oil-based ink, and even copied images with one type of correction liquid without blurring these handwritings and images. In addition, it is possible to provide a correction liquid having excellent physical properties of a coating film formed from the correction liquid and having a good white pigment dispersion stability even during long-term storage.

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mao Okawa 3-23 Muko Nagashida, Oba-machi, Onocho, Tamura-gun, Fukushima Prefecture Inside the Ono Plant, Fukushima Toei Co., Ltd. 3-23 Fukushima Toei Co., Ltd. Ono Factory (56) References JP-A-7-173416 (JP, A) JP-A-6-16981 (JP, A) JP-A-5-65440 ( JP, A) JP-A-3-285966 (JP, A) JP-A-2-97568 (JP, A) JP-A-63-142076 (JP, A) JP-A-61-36378 (JP, A) 59-59754 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 10/00 C09D 133/00-133/26

Claims (3)

(57) [Claims] 1. A white pigment, an organic solvent containing a naphthenic hydrocarbon solvent, and an acrylic resin, wherein the acrylic resin is a copolymer comprising the following monomers (I), (II) and (III). And the monomer unit (I) in the copolymer is 80 to 99.7% by weight, and the monomer unit (II) is 0.1% by weight.
2 to 20% by weight, and the monomer unit (III) is 0.1 to
5% by weight of a correction fluid. (R ¹ in the above formula is a hydrogen atom or a methyl group, R ² is a linear or branched alkyl group having 3 to 18 carbon atoms or a hydrocarbon group containing a naphthene ring or an aromatic ring, and R ³ is -C ₂ H ₄ -
Group, -CH = CH- group, -phenylene- group or -cyclohexylene- group. ) 2. The correction fluid according to claim 1, wherein the naphthenic hydrocarbon solvent is cyclohexane, methylcyclohexane or ethylcyclohexane. 3. The correction fluid according to claim 1, further comprising a petroleum resin.