JP3346624B2 - Thin film for transfer printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer printing thin film capable of smoothly applying a high-precision pattern to a transfer target having a non-planar shape.

[0002]

2. Description of the Related Art As one of the three-dimensional printing methods, printing is performed on a film capable of swelling and softening in water, and the film is swelled and softened into a gel film by floating the printing surface of the film on water, and then transferred. By pressing the body toward the water, the floated printing film with the gel film-like thin film as a support is attached to the transfer target, and then the transfer target is taken out of the water and only the gel film-like thin film as the support is removed. A method of washing and removing water is known.

In this case, a film serving as a base material is required to be a gel film-like layer when floated on the water surface, and to be attached without causing wrinkles or wraps on a transferred body.
As such a film material, use of various films listed below, particularly, a polyvinyl alcohol-based resin film has been proposed.

[0004] For example, Japanese Patent Application Laid-Open Nos. 51-21911 and 51-21914 disclose sodium polyacrylate, polyvinyl alcohol, and the like as thin films for transfer printing.
Polymers such as methylcellulose, carboxymethylcellulose, polyethylene oxide, polyvinylpyrrolidone, and polyacrylamide; animal polymers such as glue, gelatin, casein, and polypeptides; starch, cellulose, dextrin, albumin, soy protein, gum arabic, and gum tragacanth Such as vegetable polymers, or acrylic acid film, methyl ester film, vinyl chloride resin,
Urea-formaldehyde resin, nylon resin and the like are exemplified, and particularly, an oblate (starch film) is described in detail.

JP-A-54-150208 discloses that a polyvinyl alcohol resin (A) having an average degree of polymerization of 300 to 3000 and an average degree of saponification of 65 to 97 mol% is mixed with boric acid or a salt thereof to form a film. A thin film for transfer printing is shown. The publication discloses the polyvinyl alcohol resin (A)
A polymer selected from the group consisting of polyacrylamide, polyethylene oxide and methyl cellulose (B ₁ )
It also describes that starches (B ₂ ) such as starch, modified starch, dextrin and the like can be blended.

JP-A-54-92406 (JP-B-6-92406)
No. 1-3276) discloses a group consisting of 98 to 50% by weight of a polyvinyl alcohol resin (A) having an average degree of polymerization of 700 or more and an average degree of saponification of 65 to 92 mol%, polyacrylamide, polyethylene oxide and methyl cellulose. 0 to 50% by weight of selected polymer (B ₁ ), starch (B ₂ ) 0
Becomes 50 wt%, the sum of the B ₁ component and B ₂ component 2
A thin film for transfer printing which is 50% by weight is shown.

[0007] Japanese Patent Application Laid-Open No. 55-17550 discloses that a thin film of a polyvinyl alcohol-based resin having a printed pattern formed on a water surface of a dilute aqueous solution of boric acid or a salt thereof is floated with the printed surface facing up, and the object is then placed on the thin film. A transfer printing method for transferring a print pattern onto the surface of an object by pressing and settling from above is shown. Here, as the polyvinyl alcohol-based resin (A) forming the thin film, those having an average degree of polymerization of 300 to 3000 and an average degree of saponification of 50 to 97 mol% are preferably used. The publication states that the polyvinyl alcohol resin may be blended with a polymer selected from the group consisting of polyacrylamide, polyethylene oxide and methyl cellulose, and starches, modified starches, and starches such as dextrins. Have been.

Japanese Patent Application Laid-Open No. 55-25330 discloses that a phenol aqueous solution is used in place of a dilute aqueous solution of boric acid or a salt thereof. JP-A-55-1755 mentioned above.
A transfer printing method similar to that of Japanese Patent Application Laid-open No. 0 is disclosed. In the above polyvinyl alcohol resin, polyacrylamide,
It is described that a polymer selected from the group consisting of polyethylene oxide and methylcellulose, and starches such as starch, modified starch and dextrin can also be blended.

In addition, in order to prevent curling of the peripheral edge, a method is used in which a liquid capable of dissolving or swelling the polyvinyl alcohol resin is attached to the peripheral edge of the thin film (Japanese Patent Laid-Open No. Sho 5).
No. 5-27271), a method of heat-treating the edge of a thin film to a narrow width (Japanese Patent Application Laid-Open No. 55-33333), and a method of processing the edge of a thin film into an uneven shape (Japanese Patent Application Laid-Open No. 55-337). 37356
Japanese Patent Application Laid-Open No. 55-41283 discloses a method of providing a large number of small holes near the end of a thin film. A coating method (JP-A-55-61492) has also been proposed. In any of these publications, the thin film has an average degree of polymerization of 300 to 3000 and an average degree of saponification of 65 to 65.
Those formed from 97 mol% of polyvinyl alcohol resin are preferred. These publications also describe that a polyvinyl alcohol resin can be blended with a polymer selected from the group consisting of polyacrylamide, polyethylene oxide and methylcellulose, and starches, modified starches, and starches such as dextrins. ing.

[0010]

Among the transfer printing thin films listed above, a polyvinyl alcohol resin thin film, particularly a polymer selected from the group consisting of polyacrylamide, polyethylene oxide and methyl cellulose on polyvinyl alcohol resin. Is preferred. Here, the reason for blending the polymer in the latter is to adjust the swelling property and the elongation of the thin film during swelling, thereby improving the throwing power to the transfer target.

However, a conventionally used thin film of polyvinyl alcohol resin is formed by blending a polymer selected from the group consisting of polyacrylamide, polyethylene oxide and methyl cellulose with polyvinyl alcohol resin. Even so, the swelling and elongation ratio when floated on water was as large as about 1.4 to 1.8 times in area magnification, and it was unavoidable that the transfer print pattern became unclear compared to the original print pattern. It has been practiced to reduce the size of the pattern in advance to raise the plate, but even with such measures, blurring of the pattern could not be sufficiently suppressed. Further, when the contrivance as much as possible reduce the swelling expansion rate due controls or in combination of the above-described polymer having a polymerization degree and saponification degree of the polyvinyl alcohol resin in turn decreases the throwing against the transfer object I was not spared.

It is an object of the present invention to provide a transfer printing thin film which is excellent in the faithful reproducibility of a print pattern and has good throwing power with respect to an object to be transferred under such a background. Specifically, the swelling elongation 1.
An object of the present invention is to obtain a transfer printing thin film that is 35 times or less and simultaneously satisfies a throwing height of 50 mm or more.

[0013]

The thin film for transfer printing of the present invention comprises: 100 parts by weight of a polyvinyl alcohol resin (a);
Mannan, xanthan gum, guar gum, carboxymethylated guar gum, carrageenan, at least one kind of natural gum-based mucilage selected from the group consisting of locust bean gum (b) 2 to 15 parts by weight of a mixture of 10 to 50 parts by weight
It is composed of a μm thin film, and is defined as the area magnification after a lapse of three times the swelling time (the time when the wavy wrinkles disappear and the film surface becomes smooth when the thin film floats on a water surface at a temperature of 25 ° C.). The swelling / elongation rate on the water surface is 1.35 times or less.

When a polyvinyl alcohol resin alone or a known polymer (polyacrylamide, polyethylene oxide and methylcellulose) other than a natural gum-based viscous substance is blended with the resin, the swelling / elongation ratio is too high, and Swelling extension rate 1.35 times or less, throwing height 50 mm
Although the above cannot be satisfied at the same time, the phenomenon that the polyvinyl alcohol-based resin dissolves while swelling and expanding in a limited mixing ratio of the natural gum-based mucilage of the present invention and the polyvinyl alcohol-based resin is a gel-like natural Since it is effectively suppressed by the action of gum-based mucilage, the swelling elongation rate can be reduced to 1.35 times or less. In addition, by selecting the compounding ratio and the thickness of the thin film according to the gel strength of the natural gum-based mucilage, the required throwing power can be arbitrarily adjusted.

Hereinafter, the present invention will be described in detail.

The polyvinyl alcohol resin (a) has an average degree of polymerization of 300 to 4000 or more,
Those having an average degree of saponification of 65 to 97 mol% are suitably used. When the average degree of polymerization is too small, the strength of the thin film may be insufficient, and the film may be broken during the pressing of the transfer target. On the other hand, when the average degree of polymerization is extremely large, the throwing power to the transfer receiving body is reduced. When the average saponification degree is too small, the film forming property is impaired due to a decrease in the cloud point, while when the average saponification degree is too high,
Since the swelling property and the throwing power are reduced, the transfer operation cannot be performed smoothly, and the solubility at the time of film removal is insufficient. As the polyvinyl alcohol-based resin (a), two or more resins having different average polymerization degrees and different average saponification degrees may be used in combination. The polyvinyl alcohol-based resin (a) is not limited to unmodified polyvinyl alcohol, but may be a copolymer-modified or post-modified one within a range that does not impair the gist of the present invention.

The natural gum-based mucilage (b) includes mannan (konjac mannan and galactomannan), xanthan gum, guar gum, carboxymethylated guar gum,
Carrageenan or locust bean gum is used. These may be used alone or in combination of two or more.

The mixing ratio of the polyvinyl alcohol-based resin (a) and the natural gum-based viscous material (b) is 2 to 15 parts by weight (preferably 3 to 10 parts by weight) per 100 parts by weight of the former.
It is necessary to When the ratio of the natural gum-based viscous substance (b) is less than 2 parts by weight, the printed pattern becomes unclear due to a large swelling / extension rate when floated on water, while the ratio of the natural gum-based viscous substance (b) is 15%. If the weight exceeds
Although the swelling / elongation rate is low, good throwing power cannot be obtained.

A thin film composed of a mixture of the polyvinyl alcohol resin (a) and the natural gum type viscous substance (b) can be obtained by forming an aqueous solution of the mixture by a known method such as a casting method. In forming the film, it is preferable to mix an appropriate amount of a softening agent such as a polyhydric alcohol or urea in order to soften the thin film. In addition, a small amount of a surfactant or other additives can be blended.

It is necessary to set the film thickness after film formation to 10 to 50 μm. If the film thickness is less than 10 μm, the gel film strength may be reduced and the film may be cut during the transfer operation. On the other hand, when the film thickness exceeds 50 μm, the swelling time becomes too long.

In the thin film of the present invention, when the time when the wrinkles disappear and the film surface becomes smooth when the thin film is floated on the water surface at a temperature of 25 ° C. is defined as the swelling time, The swelling and elongation rate on the water surface defined by the area magnification after elapse of 3 times is set to 1.35 times or less, preferably 1.25 times or less, and more preferably 1.20 times or less. When the swelling and elongation ratio exceeds 1.35 times, the pattern after transfer is inevitably unclear and lacks in cosmetics.

Printing is performed on the surface of the transfer printing thin film. Examples of the print pattern include an arbitrary pattern such as a grain pattern, a marble pattern, a geometric pattern, an oval pattern, an abstract pattern, and characters. These print patterns are preferably
It is formed by printing an ink obtained by adding a coloring agent such as a dye or a pigment to a binder of a water-insoluble resin. Examples of the water-insoluble resin include a mixture of nitrified cotton and an alkyd resin.

[0023]

In the transfer printing thin film of the present invention, the polyvinyl alcohol-based resin (a) contains at least one selected from the group consisting of mannan, xanthan gum, guar gum, carboxymethylated guar gum, carrageenan, and locust bean gum. Because a specific amount of natural gum-based viscous substance (b) is blended, the swelling and expansion of the gel-like film when a thin film obtained from this mixture is floated on water is effectively suppressed, and faithful reproducibility of the printed pattern Will be excellent. Moreover, in spite of the suppression of the swelling / elongation rate, in the specific mixing ratio of the natural gum-based viscous substance (b),
Good throwing power to the transfer object.

[0024]

The present invention will be further described with reference to the following examples. Hereinafter, "parts" refers to parts by weight.

<Production of a thin film for transfer printing> Example 1 100 parts of polyvinyl alcohol having an average degree of polymerization of 1400 and an average degree of saponification of 89 mol% as an example of the polyvinyl alcohol-based resin (a), and a natural gum-based viscous material (b 10) guar gum as an example, glycerin 5 as a softening agent
Parts and 0.5 parts of a surfactant were dissolved in 450 parts of water by heating to prepare an aqueous solution.
A thin film having a thickness of 31 μm was produced at a temperature of ° C.

Examples 2 to 7 Polyvinyl alcohol-based resin (a) and natural gum-based mucilage
Example 1 was repeated, except that the type and ratio of (b) and the thickness of the thin film were variously changed, and the blending recipes and film forming conditions of other components were the same as in Example 1. Table 1 shows the conditions including those in Example 1.

Comparative Examples 1 to 10 The types and proportions of the polyvinyl alcohol resin (a) and the modifier (polymer or borax) (b ') conventionally used (b'), and the thickness of the thin film were changed variously. Example 1 was repeated, except that the compounding formulation and film forming conditions of the components were the same as in Example 1.
Table 2 shows the conditions.

The meanings of the symbols in Tables 1 and 2 are as follows. -PVA is a polyvinyl alcohol resin. P is the average degree of polymerization. SV is the average degree of saponification, and the unit is mol%. -CMC-Na is a sodium salt of carboxymethylcellulose. PAAm is polyacrylamide with an average molecular weight of 2,000,000. -PEO is polyethylene oxide with an average molecular weight of 4 million.

The conditions for measuring the swelling time and the swelling elongation are as follows. Swelling time When a thin film is floated on a water surface at a water temperature of 25 ° C., a wavy wrinkle is generated in the thin film in about 10 seconds, and the time when the wavy wrinkles disappear and become completely smooth is defined as a swelling time. Draw a 12cm × 12cm square in the center of the thin film with a swelling extension rate of 25cm × 25cm with an aqueous pen, float on the water surface at a water temperature of 25 ° C., and at the time of swelling time × 3 times, a size of 25cm × 25cm, 3mm thick white A polyvinyl chloride plate was pressed against the water surface to transfer the image, and the area magnification was measured as follows. Swelling extension rate (area magnification) = area of transferred shape / area of original square

[0030]

[Table 1] PVA (a) Natural gum based mucilage (a) / (b) Swelling time Swelling thickness P SV (b) Weight ratio (sec) Elongation (μm) Example 1 1700 89 Guar gum 100/10 20 1.04 31 Example 2 1700 89 Guar gum 100/5 22 1.12 32 Example 3 1700 89 Carboxymethyl 100/6 21 1.22 21 guar gum Example 4 1700 89 Carrageenan 100 / 4.5 20 1.16 20 Example 5 1700 89 Xanthan gum 100 / 4.5 16 1.23 26 Example example 6 1700 89 locust bean 100/2 + 2 15 1.04 21 gum + guar example 7 1700 89 konjac mannan 100/5 25 1.08 27 down

[0031]

[Table 2] PVA (a) modifier (b ') (a) / (b') Swelling time Swelling Film thickness P SV Weight ratio (sec) Elongation (μm) Comparative example 1 1400 89-100/0 18 1.69 31 Comparative example 2 1700 89 − 72/0 20 1.42 30 1700 96 − 28/0 Comparative Example 3 1400 89 CMC-Na 100/5 22 1.55 30 Comparative Example 4 1700 89 − 100/0 11 1.82 21 Comparative Example 5 1700 89 Guar gum 100 / 0.7 19 1.52 30 Comparative Example 6 1400 90 Borax 100 / 0.5 36 1.52 38 Comparative Example 7 1400 89 PAAm 100/5 35 1.65 30 Comparative Example 8 1400 89 PEO 100/5 32 1.80 33 Comparative Example 9 1400 89 Methylcellulose 100/535 1.55 29 Comparative Example 10 1400 89 Starch 100/5 28 1.95 32

<Performance of Thin Film for Transfer Printing> The thin film obtained above was evaluated for the performance of the thin film for transfer printing according to the evaluation method described later. Table 3 shows the results.

[0033]

[Table 3] Thickness Transfer magnification Actual device transfer evaluation height (mm) (times) Thickness Transfer accuracy Example 1 55 1.10 Almost good Good Example 2 96 1.26 Good Good Example 3 90 1.63 Good Almost good Example 4 110 1.37 Good Good Example 5 120 1.51 Good Good Example 6 52 1.13 Almost good Good Example 7 55 1.16 Almost good Good Comparative Example 1 50 2.48 Almost good Bad Comparative Example 2 26 1.88 Somewhat defective Comparative Example 3 7 defective defective defective Comparative Example 4 5 Dissolution Defective Def. Comparative Example 5 64 1.85 Almost good Slightly defective Comparative Example 6 180 2.79 Good Def. Comparative Example 7 120 2.60 Good Def. Comparative Example 8 140 2.15 Good Def. Comparative Example 9 20 1.80 Defect Slightly Defective Comparative Example 10 5 Dissolved Defective

<Evaluation method> The transfer characteristics were measured at a water temperature of 25 ° C.
The test was performed with a thin film floating on the surface of the water. Each thin film is printed by a printing device, and the printing surface is coated with an ink activating solvent (mixed and adjusted with an appropriate solvent according to the type of ink) to dissolve and soften the printing ink before transfer printing. Provided. In addition, using a real device, the throwing power and transfer accuracy for a three-dimensional object were evaluated.

The throwing height The thin film floating on the water surface gradually softens after the swelling time, becomes an elastic gel-like film with high elasticity, and has free throwing power. The time to reach this state is generally 2.5 to 3.0 times the swelling time. Therefore, when measuring the throwing height, the cup (bottom diameter 62 mm, head diameter 90 mm,
Frustum-shaped cup with a height of 250mm) from the bottom 20cm / m
The thin film was settled in water while being pressed at a speed of in, and the height from the bottom surface of the cup where good throwing power was obtained without dissolving and cutting the thin film or wrapping on the cup wall surface was measured.

Transfer Accuracy (Three-dimensional) A circle having a diameter of 12 cm is drawn at the center of a thin film of 25 cm × 25 cm with an aqueous pen, floated on a water surface at a water temperature of 25 ° C., and swelling time × 2.5
From the double point, the thin film is pressed from the center of the drawn circle at the speed of 20 cm / min and settles in water in the same way as in the case of the throwing height measurement described above, and the entire drawn circle is transferred to the cup. did. The ratio of the area of the circle after the transfer to the original area of the circle having a diameter of 12 cm was defined as the transfer accuracy for the solid. 3D transfer accuracy (magnification) = area of transferred circle ^* / area of original circle ^{** *} : Cup bottom + cup side, ^** : 113 cm ²

[0037]

According to the transfer printing thin film of the present invention, the swelling and extension when floated on water is effectively suppressed. As a result, the fidelity and reproducibility of the printed pattern is excellent, and a clear and aesthetic value is obtained. High transfer printing becomes possible. In addition, despite the suppression of the swelling / elongation rate, the throwing power to the transfer object is good, and the transfer object having an arbitrary curved surface can be handled.

Continuation of front page (72) Inventor Koji Kita 1569-2 Furuhashi, Suminami-cho, Motosu-gun, Gifu Prefecture (56) References JP-A-5-32036 (JP, A) JP-A-63-274599 (JP, A) JP JP-A-54-150208 (JP, A) JP-A-54-92406 (JP, A) JP-A-4-107504 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 3 / 12 B44C 1/175

Claims (3)

(57) [Claims] (1) 100 parts by weight of a polyvinyl alcohol-based resin (a) and at least one natural gum-based viscous material (b) selected from the group consisting of mannan, xanthan gum, guar gum, carboxymethylated guar gum, carrageenan, and locust bean gum 1) thickness of the mixture with 2 to 15 parts by weight
It consists of a thin film of 0 to 50 μm and has a swelling time
The time when the wavy wrinkles disappear when the water surface floats at 5 ° C and the film surface becomes smooth)) The swelling extension rate on the water surface defined by the area magnification after elapse of 3 times is 1.35 times or less. A thin film for transfer printing, characterized in that: The mixing ratio of 2. A polyvinyl alcohol-based resin (a) natural gum-based mucilage for 100 parts by weight (b) is 3 to 1
2. The thin film for transfer printing according to claim 1, wherein the amount is 0 parts by weight. 3. The transfer printing thin film according to claim 1, wherein the swelling / elongation ratio is 1.25 times or less.