JP3464476B1 - Photoluminescent phosphor pigment gravure printing method and apparatus - Google Patents

Abstract

Kind Code: A1 Abstract: A printed material can be mass-produced at low cost, and a plurality of cells of a gravure cylinder have a depth of 31 to 75.
By setting to μm, each cell can be filled with a sufficient ink containing a luminous pigment and / or a fluorescent pigment, thereby ensuring a luminous effect and a fluorescent effect. And the provision of such devices and printed matter. A luminous fluorescent pigment gravure printing method using a luminous pigment and / or a fluorescent pigment and printing on a printed matter 5 using a gravure cylinder 2 having a plurality of cells formed therein, wherein the depth of the cells is 31 to 31. It is a luminous fluorescent pigment gravure printing method set to 75 μm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoluminescent pigment gravure printing method for performing gravure printing on printed matter such as paper, plastic film, cloth and the like using an ink containing at least one of a luminescent pigment and a fluorescent pigment, and a method for the same.
Regarding the table

[0002]

2. Description of the Related Art Conventionally, as a method of printing on a printed matter by using a phosphorescent ink that emits light in the dark or a fluorescent ink that emits light when invisible rays such as ultraviolet rays are irradiated, a silk screen printer is used to print the above-mentioned phosphorescent ink. Alternatively, there is a method of applying a fluorescent ink to a printed matter (for example, see Patent Document 1).

[0003]

[Patent Document 1] Japanese Patent Laid-Open No. 5-262027.

[0004]

In the above-mentioned printing method by silk printing, since a sufficient ink layer can be formed on a printed matter, it is possible to secure a sufficient amount of light emission in the dark or at the time of invisible light irradiation. . But,
The silk screen printing and the pad printing methods have a problem that the mass productivity is extremely poor and the cost of printed matter becomes high.

In order to solve such a problem, it is conceivable to adopt a printing method by gravure printing instead of the silk screen printing and the pad printing method.
In the conventional gravure printing method, a sufficient ink layer (ink layer containing a pigment) cannot be formed on the printed surface of the printed matter, so that it is impossible to secure the luminous effect and the fluorescent effect.

That is, since the cell depth of the gravure cylinder used for conventional gravure printing is as shallow as 28 μm, it is not possible to fill the cell with sufficient ink (ink containing pigment), and the resin component in the ink is too small. Is as small as 15 wt%, the resin component remaining on the printed surface of the printed matter is small, the viscosity of the ink is extremely low, and the precipitation rate of the pigment is high. Furthermore, the particle size of the phosphorescent pigment or the fluorescent pigment is 6 to 7 μ.
Since m is large, the sedimentation speed of the pigment having a large particle diameter becomes fast in the ink tank for storing the ink, and the pigment is not properly supplied to the gravure cylinder cell. Due to such various factors, the conventional gravure printing method has a problem that it is not possible to secure the luminous effect and the fluorescent effect.

Therefore, according to the present invention, a printed matter can be mass-produced at a low cost, and further, by setting the depth of a plurality of cells of the gravure cylinder to 40 to 75 μm, a phosphorescent pigment and / or a fluorescent substance is provided in each cell. can be filled with sufficient ink containing pigment, thereby phosphorescent effect, phosphorescent pigments gravure mark can be ensured fluorescent effect
A printing method and an apparatus therefor are provided.

[0008]

A method for luminescent printing fluorescent pigments according to the present invention uses a fluorescent pigment and / or a fluorescent pigment, and a fluorescent pigment for printing on a printed matter by using a gravure cylinder having a plurality of cells formed therein. It is a gravure printing method, and the depth of the cell is 40 to 75 μm.
Set to the weight of the resin component in the ink used for printing above
The ratio is set to 20 to 26 wt% .

The cell having a predetermined depth having the above structure may be formed by etching by a direct method. According to the above configuration, since the method is based on gravure printing, printed matter can be mass-produced at low cost, and the cell depth can be increased.
Since the (so-called depth) was set to 40 to 75 μm, for each cell formed on the peripheral surface of the gravure cylinder,
Sufficient ink containing phosphorescent pigments and / or fluorescent pigments can be filled.

Since this ink is transferred to the printed matter when the printed matter passes between the impression cylinder rotating on contact with the gravure cylinder and the gravure cylinder, a luminous effect and a fluorescent effect can be secured. it can.

Here, when the cell depth is less than 31 μm, the ink filling amount becomes insufficient, and conversely, the cell depth is 75.
If it exceeds μm, it becomes difficult to process the cell. It should be noted that when considering both the ink filling amount and the processability, it is 40 to 7
A cell depth of 0 μm is desirable.

Further , the ink having the above-mentioned constitution comprises a solvent component of toluene (so-called thinner) and ethanol (ethyl alcohol represented by CH ₃ CH ₂ OH), and nitric cellulose (a nitrate ester of cellulose, also called nitrocellulose). Including nitrified cotton, the resin component means nitrcellulose and nitrified cotton. Then, at the time of printing, only the resin component remains on the printed surface of the printed matter to be printed, and toluene and ethanol are evaporated.

According to the above construction, the weight ratio of the resin component is set to 20 to 26 wt%, so that an appropriate amount of the resin component remaining on the printing surface of the printed matter can be secured, and the resin component having the predetermined weight ratio can be used. The viscosity of the ink becomes high, and the viscosity of the pigment slows down the sedimentation speed of the pigment in the ink tank. As a result, the luminous effect and the fluorescent effect can be further improved.

If the resin component is less than 20% by weight, the pigment precipitation rate is increased due to insufficient ink viscosity, which is not preferable. Conversely, if the resin component exceeds 26 wt%,
Cell clogging occurs. In consideration of both the pigment settling speed due to the ink viscosity and the prevention of cell clogging, the resin component is preferably 25 wt%.

In one embodiment of the present invention, the particle diameter of the above-mentioned phosphorescent pigment or fluorescent pigment is set to 3 μm or less. According to the above configuration, since the particle size of the pigment is made finer, the sedimentation speed of the pigment in the ink tank becomes slower, and the pigment is appropriately supplied to the cell of the gravure cylinder by this amount, resulting in the light storage effect. Therefore, the fluorescent effect can be further improved.

In one embodiment of the present invention, an ink tank for storing the above-mentioned ink is provided, and the stirring tank provided in the ink tank is provided.
The ink is agitated by the agitating means to precipitate the pigment in the ink.
To prevent the printing . The stirring means having the above-mentioned configuration may be set to a magnetic stirrer or other stirring members that are rotationally driven by magnetic force, and the disposing portion of the stirring means is preferably a portion where the ink on the peripheral surface of the gravure cylinder is scraped off by a doctor. . It should be noted that this stirring means is different from the conventionally used stirring bar for preventing the light and shade of the ink. Moreover, the precipitation rate can be further controlled by adding 3 to 5 vol% of a fatty acid amide wax-based precipitation inhibitor.

According to the above construction, since the pigment is agitated by the agitation means so as not to settle, the pigment is appropriately supplied to the cells of the gravure cylinder, and as a result, the luminous effect and the fluorescent effect are more remarkable. Can be improved.

A photoluminescent pigment gravure printing device according to the present invention is a photoluminescent pigment gravure printing device for printing on a printed matter by using a photoluminescent pigment and / or a fluorescent pigment.
A gravure cylinder having a plurality of cells set to a depth of 40 to 75 μm, an ink tank for storing ink to be supplied to the gravure cylinder, and an ink tank provided in the ink tank to prevent pigment in the ink from settling And a stirring means for

According to the above construction, the pigment in the ink stored in the ink tank is agitated by the agitating means so as not to settle, so that the pigment supply rate to the cells of the gravure cylinder can be increased. Moreover, since the depth of the above-mentioned cell is set to 40 to 75 μm, it is possible to fill the cell volume with sufficient ink, and to enhance the luminous effect and fluorescent effect of the printed matter on which the ink containing the pigment is transferred. You can

Therefore, the luminous phosphor having the above-mentioned structure according to the present invention
What was printed by the optical pigment gravure printing method, that is,
Printed materials are low cost (about 1/10 the cost of silk printing)
In addition to improving mass productivity, it is possible to secure a luminous effect and a fluorescent effect, and it is possible to increase the afterglow brightness as a light quantity and the afterglow time as a duration. The printed matter may be any material as long as it is a material capable of gravure printing, such as paper, resin film, cloth or the like.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. The drawings show a phosphorescent gravure printing method, its apparatus and printed matter. First, referring to FIGS.
The structure of the fluorescent pigment gravure printing apparatus will be described.

As shown in FIGS. 1 and 2, this gravure printing apparatus includes an ink tank 1 (so-called bad) in which an ink A containing a phosphorescent pigment and / or a fluorescent pigment is stored.
A gravure cylinder 2 (so-called plate cylinder), a part of the lower peripheral surface of which is immersed in the ink A, is provided on the upper part of the ink tank 1, and the gravure cylinder 2 is printed on the upper part of the gravure cylinder 2. An impression cylinder 3 for applying a pressure (particularly a strong pressure) to the ink A in the plurality of cells corresponding to the pattern is provided. Further, a doctor 4 for scraping off the excess ink A is provided on the peripheral side of the gravure cylinder 2.

Then, the printed matter 5 is supplied between the gravure cylinder 2 and the impression cylinder 3 which rotate in the direction of the arrow in FIG. 1, and a strong pressure is applied by the impression cylinder 3 to the ink A in the cells of the gravure cylinder 2 to By transferring A to the printed matter 5, the printed matter 5 is printed.

Further, the ink liquid level portion in the ink tank 1 on the side opposite to the side where the doctor 4 is disposed with the gravure cylinder 2 in between is used to prevent ink density (so-called ink unevenness) due to its rotation. A stir bar 6 is provided.

Moreover, in order to prevent the pigment from precipitating in the ink A in the ink tank 1, the portion corresponding to the portion where the ink A is scraped off by the doctor 4 (the portion where the pigment is likely to settle) is described. A stirring member 7 as stirring means is provided.

In this embodiment, the stirring member 7 is a magnetic stirrer which is rotationally driven by magnetic force.
(Magnetic stirrer) is used to drive the magnetic stirrer by the magnetic force of the motor 8 arranged in the lower part of the ink tank 1.
Instead of the stirrer, other stirring members such as a stirring propeller and a stirring rod member may be used. The stirring member 7 may be added to the doctor 4 side shown by the solid line in FIG. 1 and as shown by a virtual line α in FIG. It may be provided at a plurality of places such as between the stirring rod 6 and the inner wall of the ink tank 1 to further improve the stirring efficiency.

Here, the above ink A is composed of toluene (so-called thinner), ethanol (CH ₃ CH ₂ OH),
Nitrocellulose and nitrification cotton are included, and the weight ratio of nitrcellulose and nitrification cotton as a resin component is 2
It is set to 0 to 26 wt%, preferably 25 wt%.

This predetermined weight ratio ensures an appropriate amount of the resin component remaining on the printing surface of the printed matter 5 and increases the viscosity of the ink A so that the sedimentation speed of the pigment in the ink tank 1 becomes slow. It is configured so that the pigment supply rate to the cells of the gravure cylinder is high.

The particle diameter of the phosphorescent pigment or fluorescent pigment to be mixed with the above-mentioned ink A is set to 3 μm or less so that the pigment is miniaturized so that the sedimentation speed of the pigment in the ink tank 1 becomes slow. In addition to the above, the cell 9 is configured to be filled with a large amount of pigment particles.

A large number of cells 9 are formed on the peripheral surface of the gravure cylinder 2 corresponding to the printing pattern.
This cell 9 is formed in a rectangular cylindrical shape with a bottom as shown in the enlarged sectional view of FIG. Moreover, the depth L1 of the cell 9
(So-called depth) is set to 40 to 70 μm, more preferably 60 to 70 μm, and by setting this depth L1, it is possible to achieve both a sufficient ink filling amount filled in the cell 9 and workability. I am configuring.

Here, the depth L1 of the cell 9 is set to 70 μm.
When set to m, the length L2 of one side is set to 27 μm and the cell volume is set to 51030 μm ³ .
The cell volume is preferably 16000 μm ³ or more.

Next, the method for luminescent printing fluorescent pigments will be described. In this embodiment, the depth L1 of the cell 9 is set to 4
It is set to 0 to 75 μm (desirably 70 μm), and the weight ratio of the resin component in the ink A is 20 to 26 wt% (desirably 2
5 wt% ), the particle size of the pigment is set to 3 μm or less, and the rotation of the stirring member 7 is maintained (during printing,
The printed matter 5 is gravure-printed in a state in which it is always rotated.

When the stirring member 7 is continuously rotated in the direction of arrow a in FIG. 1, convection is formed as shown by arrow b in FIG.
It is possible to prevent the precipitation of the pigment. When the gravure cylinder 2 whose lower part is immersed in the ink A is rotated, the pigment-containing ink A is filled in each cell 9 formed on the peripheral surface thereof, and the excess ink A is scraped off by the doctor 4. It

Therefore, when the printed matter 5 is supplied between the gravure cylinder 2 and the impression cylinder 3 and pressure is applied to the ink A in the cells 9 by the impression cylinder 3, the ink A is transferred to the printed matter 5. The resin component in the ink A and the pigment contained therein remain on the printed surface of the printed matter 5, and the solvent components in the ink, that is, toluene and ethanol evaporate.

The printed matter 5 may be any material capable of gravure printing such as paper, resin film, cloth and the like, but in this embodiment, a low density polyethylene (PE / LD) having a non-absorbent surface. )Using,
For example, the characters and patterns shown in FIG. 5 were gravure printed. Note that, in FIG. 5, the portion to which the ink A is attached is hatched for convenience of illustration.

The above-mentioned phosphorescent pigment has a chemical composition of Sr.
Al ₂ O ₄ , specific gravity of 3,6 kg / m ³ , Mohs hardness of 7,
A material having stable chemical resistance and corrosion resistance and excellent heat resistance and weather resistance was used.

FIG. 4 shows the afterglow brightness (specifically, the relative brightness depending on the afterglow time) with respect to the bag-shaped rhodesity polyethylene (printed matter 5) gravure-printed under the above-described conditions (a mode in which all the above-mentioned conditions are satisfied) FIG. 4 is a characteristic diagram showing a result of actual measurement of (change of).

In this characteristic diagram, the horizontal axis shows the afterglow time (unit, time)
The relative luminance (unit: millicd / m ² ) is plotted on the vertical axis on a logarithmic scale.

The measurement conditions are as follows: Printed matter 5 (Rhodenity polyethylene) 40 cm with a 15 W desk fluorescent lamp.
Vertical irradiation (about 1000 Lx) for 20 minutes,
It was measured using a LS-100 luminance meter (measuring instrument manufactured by Minolta Co., Ltd.) at a temperature of 25 ° C., a humidity of 60%, a measuring distance of 0.4 m, and a measuring angle of 90 degrees.

Characteristic C1 is 50 wt% ink,
50 wt% phosphorescent pigment is mixed and used, the one with characteristic C2 is 60 wt% ink and 40 wt% phosphorescent pigment is mixed and used, and the one with characteristic C3 is 5
The ink of 0 wt% and the fluorescent pigment of 50 wt% were mixed and used, and the one of the characteristic C4 was the ink of 60 wt% and the fluorescent pigment of 40 wt% were mixed and used.
The characteristics C1 to C4 in FIG. 4 can be shown in the following [Table 1].

[0041]

[Table 1]

The time until the afterglow brightness (amount of afterglow) reaches ² mcd / m ² will be described. The characteristic C1 has 90 minutes, the characteristics C2 and C3 have 50 minutes, and the characteristic C4 has 40 minutes. It was possible to secure an excellent afterglow time. In order to secure a sufficient initial brightness, it is desirable that the mixing ratio of the phosphorescent pigment and / or the fluorescent pigment to the ink is 45 wt% or more.

The relationship between the brightness and the sense of brightness in darkness can be generally shown in the following [Table 2].

[0044]

[Table 2]

The ink using the fluorescent pigment mixed with the ink A containing the phosphorescent pigment has a smaller relative luminance with respect to the afterglow time. However, the ink using the fluorescent pigment has an invisible light ray. When invisible light is emitted using a light (so-called black light), it emits light,
A phosphorescent pigment or a fluorescent pigment can be selected and used alone or in combination depending on the intended use of the printed matter 5, and a pigment is gravureed on the printed matter such as paper money such as bills and tickets to prevent counterfeiting. It can also be printed.

As described above, the luminous fluorescent pigment gravure printing method of the above-described embodiment uses luminous pigment and / or fluorescent pigment, and the luminous fluorescent pigment printed on the printed matter 5 using the gravure cylinder 2 in which a plurality of cells 9 are formed. A pigment gravure printing method, wherein the depth L1 of the cell 9 is 40 to 75.
It is set to μm.

According to this structure, since the gravure printing method is used, the printed matter 5 can be mass-produced at low cost.
Moreover, the depth L1 (so-called depth) of the cell 9 is 40 to 75
Since it is set to μm, sufficient ink A containing a phosphorescent pigment and / or a fluorescent pigment is provided for each cell 9 formed in plural according to the print pattern on the peripheral surface of the gravure cylinder 2.
Can be filled.

The ink A is transferred to the printed material 5 when the printed material 5 passes between the impression cylinder 3 that rotates while being in contact with the gravure cylinder 2 and the gravure cylinder 2, so that a good luminous effect is obtained. It is possible to secure the fluorescence effect.

Here, when the cell depth L1 is less than 31 μm, the ink filling amount becomes insufficient, and conversely, the cell depth L1.
If 1 exceeds 75 μm, it becomes difficult to process the cell 9. Considering both the ink filling amount and processability ,
A cell depth of 60 to 70 μm is more desirable, but this cell depth can be arbitrarily set within the range of 40 to 75 μm according to needs.

Further, the weight ratio of the resin component in the ink A used for the above printing is set to 20 to 26 wt%. According to this configuration, the weight ratio of the resin component is 20 to 2
Since it is set to 6 wt%, an appropriate amount of the resin component remaining on the printing surface of the printed matter 5 can be secured, and the uniformity of the printing surface can be achieved. Becomes higher and the viscosity of the pigment slows down in the ink tank 1 due to this viscosity, and the amount of the pigment supplied to the cell 9 of the gravure cylinder 2 increases. As a result, the luminous effect and the fluorescent effect are further enhanced. Can be improved.

Here, if the resin component is less than 20 wt%, the pigment precipitation rate increases due to insufficient ink viscosity, which is not preferable. Conversely, if the resin component exceeds 26 wt%,
The cell 9 is clogged. In consideration of both the pigment precipitation rate due to the ink viscosity and the prevention of clogging of the cells 9, the resin component is preferably 25 wt%.

Furthermore, the particle size of the above-mentioned phosphorescent pigment or fluorescent pigment is set to 3 μm or less (desirably, a particle size as fine as possible of 2 μm or less). According to this configuration, since the particle size of the pigment is made fine, the sedimentation speed of the pigment in the ink tank 1 becomes slow, and the pigment is appropriately supplied to the cell 9 of the gravure cylinder 2 by this amount. As a result, the amount of afterglow is increased, and the effect of storing light and the effect of fluorescence can be further improved.

In addition, an ink tank 1 for storing the ink A is provided, and the ink tank 1 is provided with stirring means (see stirring member 7) for preventing precipitation of the pigment. According to this configuration, the above-mentioned stirring means (see the stirring member 7) maintains the stirring so that the pigment does not settle, and as a result, the luminous effect and the fluorescent effect can be further significantly improved.

On the other hand, the luminous fluorescent pigment gravure printing apparatus of the above-mentioned embodiment is a luminous fluorescent pigment gravure printing method in which the luminous pigment and / or fluorescent pigment is used to print on the printed matter 5, and the depth L1 is set to 40 to 75 μm. A gravure cylinder 2 having a plurality of cells 9 formed therein, an ink tank 1 in which the ink A supplied to the gravure cylinder 2 is stored,
The ink tank 1 is provided with a stirring means (see stirring member 7) for preventing the pigment in the ink A from settling.

According to this structure, since the gravure printing is used, the printed matter 5 can be mass-produced at a low cost, and the pigment in the ink A stored in the ink tank 1 is stirred by the above-mentioned stirring means (stirring). Since the stirring is maintained by the member 7) to prevent precipitation, the cell 9 of the gravure cylinder 2
However, since the supply rate of the pigment can be increased and the depth L1 of the cell 9 is set to 40 to 75 μm, it is possible to fill the cell volume with the sufficient ink A and to contain the pigment. The luminous effect and the fluorescent effect of the printed matter 5 on which the ink A is transferred can be enhanced.

Further, the luminous fluorescent pigment gravure printed matter 5 of the above-mentioned embodiment is printed by the luminous fluorescent pigment gravure printing method of the above constitution. Therefore, it is possible to improve the mass productivity at a low cost, as well as the luminous effect,
Fluorescent effect can be secured, and afterglow brightness as the amount of light
(See the relative luminance in FIG. 4) and the afterglow time as the duration can be expanded. The printed matter 5 is paper,
Any material can be used as long as it is a resin film such as low density polyethylene, cloth, or any other material capable of gravure printing, but a material having a non-absorbent surface is particularly desirable.

FIG. 6 shows another embodiment. In this embodiment shown in FIG. 6, a replenishing roller 10 is provided between the gravure cylinder 2 and the ink tank 1, and the lower part of the replenishing roller 10 is used for ink. In addition to being immersed in the ink A in the tank 1, a plurality of stirring members 7 as stirring means are provided.

Even with this structure, the other structures, functions and effects are almost the same as those of the previous embodiment shown in FIGS. 1 to 5. Therefore, in FIG. The same reference numerals are given and detailed description thereof is omitted.

In the correspondence between the constitution of the present invention and the above-mentioned embodiment, the stirring means of the present invention is the stirring member 7 of the embodiment.
However, the present invention is not limited to the configuration of the above-described embodiment.

[0060]

According to the present invention, since the gravure printing is used, the printed matter can be mass-produced at a low cost, and the depth of a plurality of cells of the gravure cylinder can be reduced to four.
Since the thickness is set to 0 to 75 μm, it is possible to fill each cell with sufficient ink containing the phosphorescent pigment and / or the fluorescent pigment, which has the effect of ensuring the phosphorescent effect and the fluorescent effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a fluorescent fluorescent pigment gravure printing apparatus used in a printing method of the present invention.

FIG. 2 is a plan view of a main part of FIG.

FIG. 3 is an enlarged sectional view of a cell.

FIG. 4 is a characteristic diagram showing a change in relative luminance depending on afterglow time.

FIG. 5 is an explanatory diagram showing an example of a printed matter.

FIG. 6 is an explanatory view showing another embodiment of the gravure printing apparatus.

[Explanation of symbols]

A ... Ink 1 ... Ink tank 2 ... Gravure cylinder 5 ... Printed matter 7 ... Stirring member (stirring means) 9 ... cell

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiroki Ishii, 1-9-9 Minoogata-cho, Izumi City, Izumi City, Osaka Prefecture (72) Inventor, Takayuki Morohashi, 338, Nonocho, Sakai-shi, Osaka Prefecture Kyoichi Kasei (56) Reference JP 2000-318290 (JP, A) JP 10-275447 (JP, A) JP 2000-158786 (JP, A) JP 2001-222225 (JP, A) ) Japanese Unexamined Patent Publication No. 2000-141861 (JP, A) Actual Development Sho 61-166836 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41M 1/10 B41M 3/06 B41F 9/00 -9/06 B41F 31/06

Claims (4)

(57) [Claims] 1. A photoluminescent pigment gravure printing method in which a photoluminescent pigment and / or a fluorescent pigment is used and a gravure cylinder in which a plurality of cells are formed is used to print on a printed matter, wherein the depth of the cell is 40 to 75 μm. And the weight ratio of the resin component in the ink used for the printing is set to 20.
Fluorescent pigment gravure printing method set to ˜26 wt% . 2. The particle diameter of the phosphorescent pigment or fluorescent pigment is 3 μm.
m or phosphorescent pigments gravure printing method according to claim 1, wherein it has been set below. 3. An ink tank for storing the ink is provided, and the ink is agitated by an agitating means provided in the ink tank.
Claim printing to prevent sedimentation of the pigment in the ink 1 or
2. The phosphorescent fluorescent pigment gravure printing method according to 2. 4. A photoluminescent pigment gravure printing device for printing on a printed matter using a photoluminescent pigment and / or a fluorescent pigment, comprising: a gravure cylinder having a plurality of cells having a depth set to 40 to 75 μm; and the gravure cylinder. A photoluminescent pigment gravure printing apparatus comprising: an ink tank in which ink to be supplied to the ink tank is stored; and an agitating unit provided in the ink tank to prevent the pigment in the ink from settling.