JPH07195894A - Mat film for water-based ball-point pen - Google Patents

Abstract

PURPOSE:To improve paintability, absorbency and water resistance by a method wherein writing layer is made of coating film consisting of fine and bulky synthetic silica, the average particle diameter and sedimentation volume of which are specified, and the like and, at the same time, over-coating layer is made of coating film of quaternary ammonium salt acrylic resin. CONSTITUTION:In a mat film, writing layer 3 is laminated, when necessary, through under coating layer, onto one side or both the sides of plastic base material 1 and, at the same time, over-coating layer 4 is laminated onto the top face of the writing layer. In this case, the writing layer 3 is made of coating film containing fine and bulky synthetic silica, the average particle diameter of which is 2-10mum and the sedimentation volume of which is 20-90ml/5g, water soluble polymer, cellulose reaction type crosslinker and catalyst therefor. On the other hand, the over-coating layer 4 is made of coating film of quaternary ammonium salt acrylic resin. Further, as the plastic film base material, polyethylene terephthalate or the like is employed. Furthermore, as the water soluble polymer, polyvinyl alcohol or the like is employed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matte film for ballpoint pens, and more particularly to a writing film which can be suitably used when a design drawing or a map drawn by a computer is output by a pen plotter, that is, a ballpoint pen. Is.

[0002]

2. Description of the Related Art With the spread of computer technology in recent years, it has become possible to output materials created by a computer with a pen plotter, and a plastic film is used as the paper.

By the way, regarding the plastic film for recording the information output by the pen plotter, those for mechanical pencils, oil-based ballpoint pens, and ink pens as writing instruments have been commercialized and are generally used. However, with regard to a writing instrument using a water-based ink, drying property and drawing property of the water-based ink are required,
Conventionally, this has been dealt with mainly by improving water-based inks and water-based pens used. Recently, studies have been conducted on a matte film that can be commonly used for a wide variety of water-based inks and water-based pens, and some of them have already been proposed.

For example, a water-based ink recording sheet in which a composition containing a cationic synthetic resin, a cellulose derivative and polyvinyl alcohol is applied to the surface of a plastic sheet to improve ink absorption and water resistance (JP-A-63-16).
No. 0875), a composition containing an ionizing radiation-curable hydrophilic monomer and an ionizing radiation-curable polyfunctional monomer is applied to the surface of a plastic film, and then irradiated with ionizing radiation to form a recording layer. A recording medium having improved recording aptitude (Japanese Patent Laid-Open No. 1-139256) has been proposed.

However, even if the ink absorbency, that is, the drying property for water-based ballpoint pens is improved to some extent by these papers, it is still insufficient, and the coating strength of the water-based ballpoint pens is not enough to withstand the contact of the balls. There is a defect that the line breakage peculiar to the water-based ballpoint pen occurs.

In other words, the ink absorbency of the water-based ink is harder to dry than the oil-based ink, and when written on a normal coating matte film, the wet state continues for several hours. In many cases, the written surface is contaminated. Therefore, for water-based ballpoint pen paper, it has been practiced to mix a water-soluble resin in the coating film to impart hydrophilicity and allow the ink to soak into the coating film.
When a water-soluble resin is blended in this way, the water resistance decreases, so when writing drawings, such as the part where the drawing lines cross,
When the image is drawn once and then drawn a second time, the coating film peels off, resulting in line breakage, or when wet with water, the coating film at that portion melts and the image disappears.

On the other hand, regarding the drawability, in the case of an oil-based ballpoint pen, the rotation of the ball at the tip is smooth, so there is almost no problem even if a normal coating mat film is used. This tendency is large because the line is easily broken because the rotation of No. is not smooth, and the surface of the plastic film is smooth in particular, and so-called sticking to the ball is poor. Furthermore, when a binder having a high absorbability for the water-based ballpoint pen ink is used, after writing with this ink, a part of the ink is laterally diffused due to the difference in the viscosity and surface tension of the ink, resulting in blurring of the line.

[0008] As described above, the plastic mat film for water-based ballpoint pens has some problems in practical use, and a product in which these problems have been completely solved is still known. Absent.

[0009]

DISCLOSURE OF THE INVENTION The present invention overcomes the above-mentioned drawbacks of the conventional water-based ballpoint pen mat film, has good ballpoint pen drawing properties and water-based ink absorbability, and enables smooth rotation of the ball of the ballpoint pen. The purpose of the present invention is to provide a mat film for water-based ballpoint pens that is free from line breakage and has excellent water resistance.

[0010]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted intensive studies in order to invent a matte film for water-based ballpoint pens which has no drawbacks in use, and as a result, devised a composition of a writing layer and an overcoat layer. It has been found that the addition of the water-soluble matte film for water-based ballpoint pens has improved ink absorbency and drawing properties, and the present invention has been completed based on this finding.

That is, the present invention provides a matte film having a construction in which a writing layer is provided on one or both sides of a plastic film substrate with an undercoat layer if necessary, and an overcoat layer is further provided thereon. A) The writing layer comprises a coating film containing fine and bulky synthetic silica having an average particle size of 2 to 10 μm and a sedimentation volume of 20 to 90 ml / 5 g, a water-soluble polymer, a fibrin reactive cross-linking agent and a catalyst thereof,
And (B) a matte film for a ball-point pen, wherein the overcoat layer comprises a coating film of a quaternary ammonium salt type acrylic resin.

The structure of the water-based ballpoint pen mat film of the present invention will now be described in detail with reference to the accompanying drawings. Figure 1
FIG. 1 is an enlarged cross-sectional view of an example of a water-based ballpoint pen mat film of the present invention, showing a structure in which an undercoat layer 2, a writing layer 3 and an overcoat layer 4 are sequentially laminated on a plastic film substrate 1. Have

As the plastic film substrate 1, polyethylene terephthalate, polyethylene, polypropylene, polyamide and the like are used, and polyethylene terephthalate is particularly preferable. This plastic film has a thickness of 25 to 250 μm, preferably 50 to 100 μm
Having a thickness of.

An undercoat layer 2 is provided on the plastic film substrate 1 in order to improve the adhesion with the writing layer 3 formed thereon. The undercoat layer 2 is not always necessary and may be omitted in some cases, and may be provided on both sides of the plastic film base material if desired. A saturated polyester resin is usually used as the undercoat layer. The thickness of this product is usually in the range of 0.5 to 1.5 μm.

Next, in the present invention, as the writing layer,
It is necessary to use a coating containing a particular synthetic silica, a water soluble polymer and a fibrin reactive crosslinker. The water-soluble polymer in this is a compound to be blended as a binder, and is preferably polyvinyl alcohol, polyvinyl acetal resin, or the like, but in addition, a carboxyl group-containing polymer, N-hydroxyalkylated polyacryamide, polyvinylpyrrolidone or the like can be used. . These water-soluble polymers preferably have a degree of polymerization of 1000 or more, and when the molecular weight is smaller than that, the ink absorption rate and receptivity become insufficient, and as a result, the ink drying property decreases.

As the polyvinyl alcohol, a partially saponified product of polyvinyl acetate is used, but a completely saponified product of polyvinyl acetate can also be used. In the case of partially saponified product, the saponification degree is 75% or more, preferably 75 to 90%
Are advantageous. If the saponification degree is less than 75%, the ink absorption speed becomes slow.

Next, the polyvinyl acetal resin is obtained by the reaction of polyvinyl alcohol and an aldehyde, and has a degree of acetalization of 2 to 20 mol%, preferably 5 to 5.
15 mol% is used. If the degree of acetalization is less than 2 mol%, sufficient water resistance cannot be obtained, and 20
If the content is higher than the mol%, the water resistance is good, but the ink drying property is deteriorated and the crosslinking property is also deteriorated.

The synthetic silica incorporated into this water-soluble polymer is obtained by heating a water-soluble silicate, for example sodium silicate, in the presence of sulfuric acid or by heating a solution of a tetrasilicate ester in the presence of acetic acid. Porous powder having an average particle size of 2 to 10 μm, preferably 3 to 9 μm
It is fine and bulky in the range of m and has a sedimentation volume of 20 to 90 ml / 5 g. When the average particle size is less than 2 μm, the slipperiness becomes too large, which causes poor rotation of the ball of the ball-point pen and causes a break in the drawn line.
If it is larger than this, the drawn line lacks smoothness and the image quality deteriorates.

Further, the sedimentation volume is a parameter of bulkiness, and if it is less than 20 ml / 5 g, sufficient ink absorbency cannot be obtained and drawing properties and color sharpness are deteriorated.
If it exceeds 90 ml / 5 g, the strength and the image quality are deteriorated.

The synthetic silica is a water-soluble polymer 100.
70 to 110 parts by weight, preferably 85 to 100 parts by weight
It is mixed in a ratio of 95 parts by weight. If this amount is less than 70 parts by weight, the roughening is insufficient and the rotation of the ball is deteriorated, which causes a break in the drawn line. If the amount is more than 110 parts by weight, the coating film strength will be reduced.

The fibrin-reactive cross-linking agent used in the present invention is a cross-linking agent having reactivity with the hydroxyl group of the fibrin, such as dimethylol ethylene urea, dimethylol alkyl triazone and methylation. Examples include dimethyloluron, dimethylolglyoxal monourein, and dimethylolpropyleneurea. These react with functional groups in the water-soluble polymer in the presence of a catalyst such as ammonium chloride, ammonium nitrate, ammonium sulfate, etc. to form a three-dimensional structure. This fibrin-reactive cross-linking agent is 20 to 8 with respect to 100 parts by weight of the water-soluble polymer.
It is mixed at a ratio of 0 parts by weight. Further, the catalyst used in combination therewith is used in a proportion of 10 to 80% by weight based on the fibrin reactive cross-linking agent. The coating liquid for forming the coating film of the writing layer is prepared by dissolving or dispersing each of the above-mentioned components in water to obtain a solid content concentration of 10 to 15%. Are, if desired, those conventionally used as an additive component of a coating liquid used in forming a normal writing layer, for example, a surfactant, a wetting agent, a stabilizer, a filler, a coloring agent, a hydrophilic property. A solvent or the like can be added.

The coating solution is applied to the surface of the plastic film directly or through an undercoat layer by a conventional method, then dried and cured to form a writing layer. The thickness of the writing layer thus formed is in the range of 5 to 30 μm, preferably 7 to 20 μm.

In the present invention, it is necessary to coat the surface of the writing layer thus provided on the plastic film with an overcoat layer made of a quaternary ammonium salt type acrylic resin. Examples of the quaternary ammonium salt type acrylic resin include copolymer salts of alkyl acrylate or alkyl methacrylate with dialkylaminoalkyl acrylate or dialkylaminoalkyl methacrylate. This quaternary ammonium salt type acrylic resin is known, and for example, a quaternary salt of a copolymer of butyl methacrylate and dimethylaminoethyl methacrylate in a molar ratio of 1: 1 is commercially available.

To form the overcoat layer, the quaternary ammonium salt type acrylic resin is dissolved in alcohol or a mixture of alcohol and water, coated on the writing layer, and then dried. The thickness of this thing is 0.5 ~
A range of 1.5 μm is suitable. This overcoat layer prevents the water-based ballpoint pen ink from bleeding,
It has an effect of suppressing troubles caused by static electricity generated when writing and rubbing paper.

[0025]

EXAMPLES The present invention will be described in more detail with reference to examples. The physical properties shown in each example are evaluated as follows. (1) Drawability: Drawing with a water-based ballpoint pen on a drafting plotter HP 7595A made by Yokogawa / Hewlett-Packard Co., Ltd., and visually observing the image quality and line breaks. A sample with a slight defect was evaluated as Δ, and a sample with a defect was evaluated as ×. (2) Color definition; black, as in the case of drawing
Plots were made with four colors of red, blue, and green, and the sharpness of the entire color tone was visually observed. As a whole, a clear one was marked with ◯, a slightly unclear one was marked with Δ, and a completely unclear one was marked with x. (3) Ink bleeding: Drawing was performed in the same manner as in the case of drawing properties, and the presence or absence of ink bleeding was observed. (4) Quick-drying property of ink: Plotted in the same manner as in the case of drawing property, and ○ when touch-dried within 30 seconds after plotting, Δ when dried for more than 30 seconds and less than 60 seconds, The case where it took more than 60 seconds was marked with x.

Example 1 A subbing layer (thickness 1.0 μm) made of a saturated polyester resin was provided on one surface of a polyethylene terephthalate film having a thickness 75 μm, and then a polyvinyl acetal resin (degree of polymerization 1700, degree of acetalization 8.0). Mol%) 7.
1 part by weight, dimethylolglyoxal monoureine 1.8 parts by weight, synthetic silica I (average particle size 9.0 μm, sedimentation volume 47 ml / 5 g) 2.2 parts by weight, synthetic silica II
(Average particle size 3.5 μm, sedimentation volume 90 ml / 5 g) 3.
2 parts by weight, kaolin clay (average particle size 2.0 μm, sedimentation volume 22 ml / 5 g) 1.0 part by weight, sodium dioctyl sulfosuccinate 0.1 part by weight, ammonium chloride 0.4 part by weight, ethyl alcohol 20.0 1 part by weight, 10.0 parts by weight of propylene glycol monomethyl ether, and 54.2 parts by weight of water are mixed to prepare a coating solution, which is applied using a wire bar and heated at 130 ° C. for 2 minutes to give a thickness of 11 μm. A writing layer was formed.

Then, a quaternary ammonium salt type acrylic resin consisting of a copolymer of butyl methacrylate and dimethylaminoethyl methacrylate in a molar ratio of 1: 1 was dissolved in a mixture of water and ethyl alcohol, and the surface of the writing layer was dissolved. It was applied and heated at 130 ° C. for 1 minute to form an overcoat layer having a thickness of 1 μm.

The physical properties of the matte film thus obtained are shown in Table 1. The kaolin clay used as a component of the writing layer in this example is for improving the pencil writing property, and the propylene glycol monomethyl ether is for improving the coating property.

Example 2 Example 1 was repeated except that the polyvinyl acetal resin in the writing layer coating solution in Example 1 was replaced with the same amount of polyvinyl alcohol resin (polymerization degree 2000, saponification degree 88.0 mol%). A matte film was produced in exactly the same manner.
The physical properties of this product are shown in Table 1.

Comparative Example 1 A matte film was produced in exactly the same manner as in Example 1 except that the same amount of water-soluble melamine resin was used in place of dimethylolglyoxalmonourein in the writing layer coating solution in Example 1. did. The physical properties of this product are shown in Table 1.

Comparative Example 2 In exactly the same manner as in Example 1, a writing layer was formed on a polyethylene terephthalate film having an undercoat layer, and a matte film having no overcoat layer was produced. The physical properties of this product are shown in Table 1.

[0032]

[Table 1]

Comparative Examples 3 to 5 Matte films were produced in exactly the same manner except that the synthetic silica in Example 1 was replaced with the synthetic silica or natural silica shown in Table 2. The physical properties of this product are shown in Table 2.

[0034]

[Table 2]

[0035]

EFFECTS OF THE INVENTION The matte film of the present invention is excellent in the drawing ability of a ballpoint pen and the absorbability of water-based ink, the rotation of the ball when drawing with a ballpoint pen is smooth, there is no line break, and the water resistance is good. It is suitable for outputting the designed drawings and maps.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of an example of the present invention.

[Explanation of symbols]

 1 Plastic Film Base Material 2 Undercoat Layer 3 Writing Layer 4 Overcoat Layer

Claims (3)

[Claims] 1. A matte film in which a writing layer is provided on one or both sides of a plastic film substrate with an undercoating layer if necessary, and an overcoat layer is further provided thereon, wherein (A) the writing layer. But the average particle size is 2 to 10μ
m, a fine and bulky synthetic silica having a sedimentation volume of 20 to 90 ml / 5 g, a water-soluble polymer, a coating film containing a fibrin-reactive cross-linking agent and its catalyst, and (B) the overcoat layer is a quaternary grade. A matte film for a ballpoint pen, characterized by comprising a coating film of an ammonium salt type acrylic resin. 2. The matte film for a ballpoint pen according to claim 1, wherein the plastic film substrate is polyethylene terephthalate, polyethylene, polypropylene or polyamide. 3. The matte film for a ballpoint pen according to claim 1, wherein the water-soluble polymer in the writing layer is polyvinyl alcohol, polyvinyl acetal, polyvinylpyrrolidone or poly- (N-hydroxyalkyl acrylamide).