JP6922520B2 - Gravure coating plate and coating equipment - Google Patents

Description

The present invention relates to a gravure coating plate and a coating apparatus.

Conventionally, as a coating device for applying a flat coating to a base material unwound from an unwinding roll, drying it, and winding it on a winding roll, a spiral groove called a diagonal line type has been formed on the peripheral surface of the cylinder. A coating device that uses a gravure coating plate to coat the base material by reversing the rotation direction of the plate and the transport direction of the base material is known as a reverse direct type coating device.

In the reverse direct type coating device, for example, as shown in FIG. 6, the gravure coating plate 50 is immersed in the coating liquid 11 stored in the coating liquid storage container 10 while the lower portion of the gravure coating plate 50 is immersed in the coating liquid 11. Rotating in the a direction, the groove 51 formed on the peripheral surface of the gravure coating plate 50 is filled with the coating liquid 11, and the excess coating liquid 11 is scraped off by the doctor blade 20, and the coating liquid 11 in the groove 51 is removed. , The base material is conveyed in the b direction opposite to the rotation direction a of the gravure coating plate 50 by the pressure of the impression roll 41 rotating in the c direction opposite to the rotation direction a of the gravure coating plate 50. Examples thereof include a coating device that is transferred to 30 coated surfaces (see, for example, Patent Document 1).

Further, as an example of a reverse direct type coating device that does not use an impression roll, as shown in FIG. 7, the lower portion of the gravure coating plate 50 is immersed in the coating liquid 11 stored in the coating liquid storage container 10. While rotating the gravure coating plate 50 in the a direction, the groove 51 formed on the peripheral surface of the gravure coating plate 50 is filled with the coating liquid 11, and the excess coating liquid 11 is scraped off by the doctor blade 20. The transport roll 42 that rotates in the d direction opposite to the rotation direction a of the gravure coating plate 50 and the transport roll 43 that rotates in the e direction opposite to the rotation direction a of the gravure coating plate 50. A kiss-reverse coating in which the coating liquid 11 in the groove 51 is transferred to the coating surface of the substrate 30 by the tension of the substrate 30 conveyed in the direction b opposite to the rotation direction a of the gravure coating plate 50. Examples include engineering equipment (see, for example, Patent Documents 2 and 3).

By the way, the coating liquid 11 in the groove 51 flows downward along the groove 51 due to gravity, and at the same time, the gravure coating plate 50 is lifted up together with the groove 51 by rotating the gravure coating plate 50. The coating liquid 11 flows in the width direction of the base material 30, and the coating liquid 11 reverses from the end portion of the base material 30 in the width direction to the non-coated surface of the base material 30, contaminating the impression roll 41 or the transport roll 43. There is.

For example, as shown in FIG. 8, when the groove 51 descends to the right, when the gravure coating plate 50 rotates, the coating liquid 11 flows in the direction f from left to right, and the coating liquid 11 flows from the left end portion in the width direction of the base material 30. When the coating liquid 11 reverses to the non-coated surface of the base material 30, and conversely, when the groove 51 descends to the left, the coating liquid 11 flows from right to left in the width direction of the base material 30, and the base material 30 The coating liquid 11 may reverse from the right end portion to the non-coated surface and contaminate the impression roll 41 or the transport roll 43.

In order to prevent the backing of the coating liquid 11 from the end portion of the base material 30 to the non-coated surface, as shown in FIGS. 9 and 10, the base material 30 is formed at both ends in the width direction. The earmuffs films 31 and 32 are sandwiched between the material 30 and the gravure coating plate 50 for coating.

However, as shown in FIG. 11, by sandwiching the earmuffs films 31 and 32 between the base material 30 and the gravure coating plate 50 at both ends of the base material 30 in the width direction, the earmuffs film 31 Since the base material 30 hangs down between 32, the distance between the base material 30 and the gravure coating plate 50 becomes large near the earmuff film, and the film thickness of the coating film becomes thick at the end. , A problem called earmuffs occurs at the end of the take-up roll. The ear height due to the partial difference in thickness is a cause of problems such as deformation of the base material or winding wrinkles, and we are trying to eliminate it by thinning the ear pad film or shaking it, but it is a fundamental solution. Has not arrived.

Japanese Patent No. 37833341 Japanese Unexamined Patent Publication No. 2010-5543 Japanese Unexamined Patent Publication No. 2011-56352

The present invention has been made in consideration of such circumstances, and an object of the present invention is to avoid the backside of the coating liquid to the non-coated surface and the ear height at the end of the take-up roll.

In order to solve the above problems in the present invention, first, in the invention of claim 1,
A columnar gravure coating plate, which is a peripheral surface facing one end of two widthwise ends of a base material to be coated, straddling the end portion in the circumferential length direction. It has a bows portion with no grooves formed all around, and when viewed facing the plate surface with the axial direction of the gravure coating plate as the left-right direction, the peripheral surface on the right side of the bows portion is coated with gravure from the bows portion. groove downward-sloping are formed spirally toward the axial right end of Engineering edition, the lower left toward the Bowes portion on the peripheral surface of the left Bowes portion axially left end of the gravure coating plate The gravure coating is characterized in that the grooves are formed in a spiral shape, and at the time of coating, the grooves are rotated in a direction in which the grooves appear to move from the bows portion toward the axial end portion of the gravure coating plate. It is a version.

Further, in the invention of claim 2, using a gravure coating plate according to claim 1, that with respect to a rotation direction of the gravure coating plate conveyance direction of the substrate as an object to be coated material are opposite to each It is a coating device characterized by.

The invention of claim 1 has a bows portion having no groove formed on the peripheral surface facing one of the two end portions in the width direction of the base material, and is provided on the peripheral surface on the right side of the bows portion. Since the gravure coating plate is characterized in that the downward-sloping groove is spirally formed and the downward-sloping groove is spirally formed on the peripheral surface on the left side of the bows portion, the rotation direction and the base material of this plate. When the substrate is coated in the opposite direction to the transport direction, the coating liquid flows from left to right on the right side of this one end, and flows from right to left on the left side of this one end. Therefore, there is an effect that the coating liquid does not reverse to the non-coated surface of the base material from any end in the width direction of the base material.

Further, in the invention of claim 1, since the coating liquid does not reverse to the non-coated surface of the base material from any end in the width direction of the base material, the earmuff film becomes unnecessary. This has the effect of avoiding ear height at the end of the take-up roll.

Further, the invention of claim 2 is a coating apparatus, characterized in that the base material is coated by reversing the rotation direction of the gravure coating plate according to claim 1 and the transport direction of the base material. The coating liquid does not reverse to the uncoated surface of the substrate from any end in the width direction of the material, eliminating the need for earmuffs and avoiding ear height at the end of the take-up roll. There is an effect.

Therefore, the present invention has the effect of avoiding the backing of the coating liquid to the non-coated surface and the ear height at the end of the take-up roll.

The schematic front view of the coating apparatus according to 1st Embodiment of the gravure coating plate of this invention. The schematic front view of the coating apparatus according to 2nd Embodiment of the gravure coating plate of this invention. The schematic front view of the coating apparatus according to the Example of the gravure coating plate of this invention. The schematic front view of the coating apparatus by the comparative example of the gravure coating plate of this invention. The figure explaining the ear height calculation method. Schematic side view of a reverse direct type gravure coating device. Schematic side view of a kiss reverse type gravure coating device. The schematic front view of the first example of the conventional gravure coating apparatus. The schematic perspective view of the 2nd example of the conventional gravure coating apparatus. Schematic front view of a second example of a conventional gravure coating device An enlarged view of the portion indicated by A in FIG. 10 is enlarged.

Hereinafter, embodiments of the present invention will be described.

As shown in FIGS. 1 and 2, the gravure coating plate of the present invention includes one end of the two widthwise ends of the base material 30 (the left end in FIG. 1 and the right end in FIG. 2). It has a bows portion 53 on which no grooves are formed on the facing peripheral surfaces, and a downward-sloping groove 51 is spirally formed on the peripheral surface on the right side of the bows portion 53, and left on the peripheral surface on the left side of the bows portion 53. This is a gravure coating plate 50 in which the descending groove 52 is formed in a spiral shape.

In addition, in FIGS. 1 and 2, the inclination angle θ1 of the groove 51 descending to the right and the inclination angle θ2 of the groove 52 descending to the left have a relationship of θ2 = 180 ° −θ1 with degrees as a unit of angle. , As shown in Examples described later, this relationship does not necessarily have to be present.

In the gravure coating plate of the present invention, a groove is formed on the peripheral surface facing one end (the left end in FIG. 1 and the right end in FIG. 2) of the two widthwise ends of the base material 30. It has a bows portion 53 that is not provided, and a groove 51 that descends to the right is spirally formed on the peripheral surface on the right side of the bows portion 53, and a groove 52 that descends to the left is spirally formed on the peripheral surface on the left side of the bows portion 53. Therefore, when the base material is coated with the rotation direction of the gravure coating of the present invention and the transport direction of the base material reversed, from one end (the left end in FIG. 1 and the right end in FIG. 2). On the right side, the coating liquid 11 flows in the direction f from left to right, and on the left side of one end (the left end in FIG. 1 and the right end in FIG. 2), the coating liquid 11 flows in the direction g from right to left. The coating liquid 11 does not reverse to the non-coated surface of the base material 30 from any end in the width direction of the base material 30.

Since the coating liquid 11 does not reverse to the non-coated surface from any end of the base material 30 in the width direction, the earmuff film becomes unnecessary, and the ear at the end of the take-up roll is eliminated. High is avoided.

Examples and comparative examples of the present invention will be described below.

<Example>
As shown in FIG. 3, the base material 30 has a bows portion 53 having no groove formed on the peripheral surface facing the left end portion in the width direction, and a groove 51 descending to the right on the peripheral surface on the right side of the bows portion 53. Is spirally formed, a left-sloping groove 52 is spirally formed on the left peripheral surface of the bows portion 53, the inclination angle θ1 of the right-sloping groove 51 is 75 degrees, and the inclination angle θ2 of the left-sloping groove 52. The width of the bows portion 53 is 10 mm, the groove 51 and the groove 52 are all 170 L / in, the depth is 45 μm, and the cell volume is 23 cm ³ /. The m ² was used as the gravure coated version of the embodiment of the present invention.

In a kiss-reverse type gravure coating apparatus using the gravure coating plate of the embodiment of the present invention, a water-based ink coating liquid was applied to a PET (polyethylene terephthalate) film having a thickness of 12 μm as a base material and dried. It was later wound on a take-up roll. During this coating, no earmuff film was sandwiched between the substrate and the gravure coating plate at any end of the substrate in the width direction.

<Comparison example>
As shown in FIG. 4, a gravure coating plate 50 in which a downward-sloping groove 51 is spirally formed on the peripheral surface and the inclination angle θ1 of the downward-sloping groove 51 is 75 degrees, and the groove 51 is a line. A gravure-coated plate of a comparative example of the present invention was prepared in which the number was 170 L / in, the depth was 45 μm, and the cell volume was 23 cm ³ / m ^2.

A kiss-reverse type gravure coating apparatus using the gravure coating plate of the comparative example of the present invention, on a PET (polyethylene terephthalate) film having a thickness of 12 μm as a substrate, as shown in FIG. 4, in the width direction of the substrate 30. A silicon PET (silicon-coated polyethylene terephthalate) film is sandwiched between the base material 30 and the gravure coating plate 50 as ear pad films 31 and 32 at both ends of the above, and a water-based ink coating solution is applied and dried. After that, it was wound on a take-up roll.

<Evaluation>
As shown in FIG. 5, in the take-up roll 33 in which the base material is wound 1000 m, the height at the position of 100 mm from the end of the base material is subtracted from the height at the position of 10 mm from the end of the base material. Was calculated and evaluated as ear height. That is, the ear height is the height at a position of 10 mm from the end of the base material with reference to the height at the position of 100 mm from the end of the base material in the take-up roll 33 in which the base material is wound 1000 m. be.

Table 1 below summarizes the features of the gravure-coated plates of Examples and Comparative Examples of the present invention.

Table 2 below shows the evaluation results of ear heights of Examples and Comparative Examples of the present invention.

As described above, the ear height is 1 mm in the example, whereas it is 5 mm in the comparative example. Therefore, in the example of the present invention, the earmuff film is unnecessary and the end of the winding roll is used. It can be confirmed that the ear height of the part is avoided.

10 ... Coating liquid storage container 11 ... Coating liquid 20 ... Doctor blade 30 ... Base material 31 ... Ear pad film 32 ... Ear pad film 33 ... Winding roll 41 ... Impression roll 42 ... Transfer roll 43 ... Transfer roll 50 ... Gravure coating Plate 51 ... Groove 52 ... Groove 53 ... Bows part A ... Enlarged part a ... Arrow b indicating the direction of rotation of the gravure coating plate ... Arrow c indicating the direction of transport of the base material c ... Arrow d indicating the direction of rotation of the impression roll ... Arrow e indicating the rotation direction of the transport roll 42 ... Arrow f indicating the rotation direction of the transport roll 43 ... Arrow g indicating the flow direction of the coating liquid ... Arrow θ1 indicating the flow direction of the coating liquid ... … Inclination angle of the downward-sloping groove

Claims (2)

A columnar gravure coating plate, which is a peripheral surface facing one end of two widthwise ends of a base material to be coated, straddling the end portion in the circumferential length direction. It has a bows portion with no grooves formed all around, and when viewed facing the plate surface with the axial direction of the gravure coating plate as the left-right direction, the peripheral surface on the right side of the bows portion is coated with gravure from the bows portion. groove downward-sloping are formed spirally toward the axial right end of the engineering version, the groove of the lower left toward the Bowes portion on the peripheral surface of the left Bowes portion axially left end of the gravure coating plate Is formed in a spiral shape, and at the time of coating, the groove is rotated in a direction in which the groove appears to move from the bows portion toward the axial end portion of the gravure coating plate. .. Using a gravure coating plate according to claim 1, coating apparatus, wherein the conveying direction of the substrate as an object to be coated material is opposite to the rotational direction of the gravure coating plate.

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