JP2009291698A - Coating apparatus and coating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating apparatus and a coating method that can decrease the bulging of an end appearing upon scaling off a viscous coating liquid, is suitable for suppressing improper scaling-off from occurring, and can improve dimensional precision in the width-direction of a coating liquid having been transcribed or applied and the precision of the uniformity of its film thickness. <P>SOLUTION: The coating apparatus that scales off a coating liquid from the outer circumferential face of its coating roller (an application roller 1 in Fig.2) by causing a blade 3 to contact with the outer circumferential face of the coating roller, is characterized in that the contact position cp at which the blade 3 contacts the coating roller is disposed downward from a horizontal plane hp<SB>1</SB>passing through the center of the coating roller in terms of center angle in the range of from 10° to 80°, and the blade 3 is tilted upward from a horizontal plane hp<SB>2</SB>containing the contact position cp of the blade 3 and the contact angle ca to the coating roller which the blade 3 makes with the horizontal plane hp<SB>2</SB>is >0° and ≤10°. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In the present invention, the coating liquid is applied with a blade from the outer peripheral surface or coated surface of a coating roll used to apply a coating liquid (for example, an adhesive or paint) to a strip-shaped substrate (for example, a polymer film or paper). The present invention relates to a coating apparatus and a coating method for scraping a predetermined amount.

  Conventionally, as a method of scraping viscous fluid such as ink from the outer peripheral surface of a roll, for example, a doctor blade method described in Patent Document 1 is known. In this method, as shown in FIGS. 5 to 8 of the document, the doctor blade (11) is pressed horizontally against the outer peripheral surface of the roll (5), and the roll (5 ) The viscous fluid (surplus ink) on the outer peripheral surface is scraped off (see also the description of paragraph 0026 of the document 1).

  However, in the conventional doctor blade system as described above, when a highly viscous fluid is scraped off, the end of the viscous fluid remaining on the outer peripheral surface of the roll (5) after scraping as shown in FIG. A scraping defect occurs in which the scraped end portion is raised. The cause is considered to be that the viscous fluid scraped off does not fall smoothly downward, but wraps around from the both ends of the doctor blade (11) to the back side.

  As described above, when the scraped end of the viscous fluid is raised, when the viscous fluid is transferred from the roll to the base, the pressure between the base and the roll due to the transfer is scraped off and the raised portion of the end As a result, the width of the viscous fluid after transfer / application is wider than the expected width, or the thickness of the viscous fluid after transfer / application is not uniform, and only the edges are partially Problems such as a decrease in the dimensional accuracy in the width direction of the viscous fluid after transfer and application, and a uniform accuracy in the film thickness occur, such as becoming thicker.

  In addition, the code | symbol in the parenthesis used in the said description and the code | symbol in Fig.6 (a) (b) are used by patent document 1. FIG.

Japanese Patent Laid-Open No. 11-320842

  The present invention has been made to solve the above-described problems, and the object of the present invention is to reduce the swell of the scraped end of the coating liquid made of a viscous fluid and to suppress the occurrence of scraping defects. Therefore, an object of the present invention is to provide a coating apparatus and a coating method that can improve the dimensional accuracy in the width direction of the coating liquid after transfer / coating and the uniformity accuracy of the film thickness.

  The coating apparatus according to the present invention includes a coating roll for applying a coating liquid, a coating liquid supply means for supplying a coating liquid to the outer peripheral surface or the surface to be coated of the coating roll, and the outer peripheral surface or the coating target of the coating roll. A blade that contacts the surface and scrapes off the coating liquid, and the contact point of the blade with respect to the coating roll is within a range of 10 ° to 80 ° below a horizontal plane passing through the center of the coating roll, The contact angle of the blade with the coating roll is in the range of more than 0 ° and 10 ° above the horizontal plane including the contact point of the blade, and the blade is inclined obliquely within the range. It contacts the roll.

  In the coating apparatus according to the present invention, the tip of the blade is cut from only one side of the both sides of the blade and inclined in one direction, and the gradient of the inclination is in the range of 10 ° to 80 °, The blade can employ a configuration in which both of the blade surfaces that are not cut are arranged so as to approach the outer peripheral surface of the coating roll.

  Further, in the coating apparatus according to the present invention, the coating roll is a plain roll having no irregularities on the outer peripheral surface, and the planar shape of the tip of the blade is a shape having at least one notch recess that does not scrape the coating liquid. There may be.

  The coating method according to the present invention is characterized in that the coating liquid is scraped off from the outer peripheral surface or the surface to be coated of the coating roll using the coating apparatus of the present invention.

  The coating method according to the present invention is characterized in that the coating liquid is partially coated on the surface of the base material in a streak pattern with substantially the same width as the notched recess using the coating apparatus of the present invention.

  According to the present invention, the blade is configured such that the contact point of the blade with the coating roll is within a range of 10 ° to 80 ° below the horizontal plane passing through the center of the coating roll, and further, the contact of the blade with the coating roll. The angle was set in the range of more than 0 ° and 10 ° above the horizontal plane including the contact point of the blade, and the blade was inclined obliquely and contacted the coating roll within this range. For this reason, the rising of the scraped edge of the coating liquid made of viscous fluid is reduced, and it is possible to suppress the occurrence of scratching defects. Also, the width-wise dimensional accuracy and film thickness of the coating liquid after transfer / coating are reduced. The effect of improving the uniform accuracy was obtained.

  As described above, when the blade is inclined obliquely within a range of more than 0 ° and 10 ° above the horizontal plane including the contact point between the blade and the coating roll, the coating liquid scraped off at the tip of the blade is Since the lower surface of the blade, that is, the lower surface of the blade, looks like a ceiling with an upward slope from the contact point, the coating liquid is more easily peeled and dropped by its own weight from the lower surface of the blade. It is considered that the above-mentioned effects were obtained because the coating solution wraps around the side less.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the accompanying drawings. The coating roll refers to an application roll for transferring the coating liquid to the base material to be applied, a pickup roll for attaching the coating liquid to be applied to the outer peripheral surface, and holding the base material at a position where the coating liquid is applied to the base material. It is a general term for backing rolls.

  FIG. 1 is an overall schematic diagram of a coating apparatus to which the present invention is applied, FIG. 2 is an explanatory diagram of a contact point and a contact angle of a blade, and FIG. 3 is an explanatory diagram of an inclination and gradient of the blade tip by cutting.

<Outline of coating device>
In FIG. 1, T ₀ is a coating solution before being supplied to the outer peripheral surface of the application roll 1, T ₁ is a coating solution before scraping with the blade 3, and T ₂ is a coating solution after scraping with the blade 3. Show. The present coating apparatus M includes an application roll 1 for coating a coating liquid T _2, a coating liquid supply means 2 for supplying the coating liquid T ₀ on the outer peripheral surface of the application roll 1, in contact with the outer peripheral surface of the application roll 1 The blade 3 for scraping the coating liquid T ₁ from the outer peripheral surface, the backing roll 4 arranged in parallel with the application roll 1, and the belt-like base material K between the outer peripheral surfaces of the application roll 1 and the backing roll 4 in order. comprising a base material supply unit 5 supplies, winding means for winding the substrate K, the coating liquid T ₂ is coated with (winding roll 11).

<Detailed configuration of application role and backing roll>
The application roll 1 is a plain roll having no irregularities on the outer peripheral surface, and can be rotated in the direction of the arrow R1 in the figure with the roll center as the rotation center. The backing roll 4 is also composed of a plain roll, and can be rotated in the direction of the arrow R2 in the figure with the roll center as the center of rotation. Then, in the coating apparatus M, and the substrate K is sandwiched between the outer peripheral surfaces of the rolls (application roll 1 and the backing roll 4), the coating liquid T ₂ of the application roll 1 outer peripheral surface on the surface of the substrate K Transferred and applied.

<Detailed Configuration of Coating Solution Supply Unit>
The coating liquid supply means 2 forms a coating liquid reservoir 7 having a funnel-shaped cross section between the outer circumferential surface of the application roll 1 and the outer circumferential surface of the roll knife 6 disposed adjacent thereto. The coating liquid T ₀ is continuously supplied to the outer peripheral surface of the application roll 1 that rotates from 7.

This type of coating solution supply means 2 may be any device that can continuously supply the coating solution T ₀ to the outer peripheral surface of the application roll 1. Such coating liquid supply unit 2, for example, and method of immersing the outer peripheral surface in the coating liquid T ₀ that is stored in container 12 of the coating roll as shown in FIG. 5 (a) (b) directly, FIG. (C such as direct supply method a coating liquid T ₀ of a known T-die 13 as), it is possible to adopt another different method a coating liquid supply unit 2 described above.

FIG. 5A shows two examples of coating rolls, and FIG. 5B shows three coating rolls, of which the outer peripheral surface of the lower coating roll (pickup roll 8) is the coating liquid T ₀ in the container 12. However, the number of coating rolls is not limited to these examples. In these examples, a gravure roll is generally used as the pickup roll 8, but a plain roll may be used instead. FIG. 5C shows an example in which the coating liquid T ₀ is directly supplied from the T die 13 to the base material K on the backing roll 4 and applied. However, the coating liquid T ₀ is supplied to the application roll 1 described above. The coating liquid may be transferred from the application roll 1 to the substrate K and applied.

<Detailed configuration of blade>
In the following description of the “contact point cp of the blade 3 with respect to the application roll 1”, the horizontal plane hp ₁ passing through the center of the application roll 1 in FIG. 2 is set as a reference (0 °). In the following description of “contact angle ca of the blade 3 with respect to the application roll 1”, the horizontal plane hp ₂ including the contact point cp of the blade 3 in FIG. ₂ is set as a reference (0 °).

The contact point cp of the blade 3 with the application roll 1 is set within a range of 10 ° to 80 ° below a horizontal plane hp ₁ passing through the center of the application roll 1 as shown in FIG. In FIG. 2, as an example of the contact point cp, an example is shown in which the blade 3 is in contact with the application roll 1 at a position of about 54 ° below the horizontal plane hp ₁ .

The contact angle ca of the blade 3 with respect to the application roll 1 is set in the range of more than 0 ° and 10 ° above the horizontal plane hp ₂ including the contact point cp of the blade 3 described above. In FIG. 2, as an example of the contact angle ca, an example is shown in which the blade 3 is inclined obliquely and contacts the application roll 1 with an inclination of about 5 ° above the horizontal plane hp ₂ .

Tip of the blade 3, as shown in FIG. 3 (a) (b), is only cut from one side of the surface S ₁ of the blade duplex (S _{1, S 2)} is inclined in one direction, the slope of the inclined It is set within the range of 10 ° to 80 °. Then, the blade 3, it is preferable that the direction of the surface S ₂ that is not cut out of the blade both surfaces (S _{1, S 2)} is arranged so as to approach the outer peripheral surface of the application roll 1 (FIG. 3 (a )), And the cut surface S ₁ may be arranged so as to approach the outer peripheral surface of the application roll 1. 3A and 3B show an example in which the tip of the blade 3 is inclined only in one direction with a gradient of about 60 ° as an example of the gradient of the tip of the blade 3.

The planar shape of the tip of the blade 3 can be a shape having a plurality of notched recesses 9 that do not scrape the coating liquid T ₁ (see FIG. 1) from the outer peripheral surface of the application roll 1 as shown in FIG. The coating liquid T ₂ (see FIG. 1) that has not been scraped off by the notch recess 9 remains in a streak shape on the outer peripheral surface of the application roll 1, and the streaky coating liquid T ₂ is formed as shown in FIG. It is transferred to the surface of the substrate K, and a coating solution can be partially applied.

<Detailed configuration of substrate supply means>
The base material supply means 5 includes a feeding roll 10 in which a belt-shaped base material K is wound in a roll shape, and feeds the base material K from the feeding roll 10 toward the outer peripheral surface of the application roll 1 by a drive roller (not shown). The fed base material K passes between both outer peripheral surfaces of the application roll 1 and the backing roll 4 and is wound around a winding roll 11 as a winding means. In addition, you may use so that the winding roll 11 may function as a drive roller, without providing a drive roller.

  Next, the operation of the coating apparatus M configured as described above will be described with reference to FIG.

In the coating apparatus M, the application liquid 1 rotates in the direction of the arrow R <b> 1 in FIG. 1, whereby the coating liquid T _{0 in} the coating liquid storage unit 7 is supplied to the outer peripheral surface of the application roll 1. The supplied coating liquid T ₁ adheres to the outer peripheral surface of the application roll 1 by its viscosity and surface tension, is sequentially transferred in the direction of the blade 3, and is scraped off at the tip of the blade 3. As shown in FIG. 4, there is a notch recess 9 at which the coating liquid T ₁ is not scraped off at the tip of the blade 3, so that the coating liquid T ₂ remaining after scraping is striped with substantially the same width as the notch recess 9. Become.

On the other hand, the backing roll 4 rotates in the direction of arrow R2 in FIG. 1 corresponding to the rotation of the application roll 1. Then, the base material K is fed from the feeding roll 10 in correspondence with the rotation of both the rolls 1, 4, and the fed base material K passes between the outer peripheral surfaces of the both rolls 1, 4. In this case, streaky coating liquid T ₂ of the application roll 1 outer peripheral surface is transferred to the surface of the substrate K. Therefore, the coating liquid T ₂ streaked substantially the same width on the surface of the substrate K after passing between the outer peripheral surface and the cutout recess 9 of the blade 3 of the rolls 1 and 4 are partially coated . The substrate K after the transfer / coating is finally wound around the winding roll 11 through a drying process (not shown).

As described above, in the coating apparatus M of the present embodiment, as the configuration of the blade 3, (1) the contact point cp of the blade 3 with the application roll 1 is approximately lower than the horizontal plane hp ₁ passing through the center of the application roll 1. (2) The contact angle ca of the blade 3 with respect to the application roll 1 is about 5 ° above the horizontal plane hp ₂ including the contact point cp, and the blade 3 has an inclination of about 5 °. Adopts a configuration in which the application roll 1 is inclined and contacted with the application roll 1, so that the swell of the scraped end of the coating liquid (see FIG. 6) is reduced on the outer peripheral surface of the application roll 1, thereby suppressing the occurrence of scraping defects. We were able to.

The principle or reason for the above-mentioned effect is considered as follows. When employing a blade structure as described above, where the coating liquid scraped off by the tip of the blade 3 from escaping, i.e., the lower surface S ₁ of the blade 3 is uphill from the contact point cp as shown in FIG. 3 Since it becomes like a ceiling, the coating liquid is easily peeled and dropped by its own weight from the lower surface of the blade 3, and the coating liquid is applied to the blade back surface (upper surface S ₂ ) side from the gaps on both side edges and the notch recess 9. Less wraparound.

  Further, according to the present coating apparatus M, as described above, the swell of the scraped end portion of the coating liquid (see FIG. 6) has decreased, so that the amount of the swelled portion that expands due to the transfer pressure is reduced and transferred to the substrate. -The dimensional accuracy of the applied coating solution in the width direction is improved, and the uniformity accuracy of the coating solution after transfer and coating is also improved.

Furthermore, even when the following two conditions (condition 1 and condition 2) are satisfied, the swell of the scraped end of the coating liquid (see FIG. 6) is reduced, and the occurrence of scraping defects can be suppressed. The principle or reason is considered as follows. When a blade configuration satisfying the following conditions 1 and 2 is adopted, the direction in which the excess coating liquid scraped off at the tip of the blade 3 escapes (the rotation direction R1 of the coating roll (application roll 1)) Since the lower surface S _{1 of the} blade 3 is warped in the direction of reversal, the coating liquid is more easily peeled and dropped by its own weight than the lower surface S _{1 of} the blade 3, and the rear surface (upper surface S ₂ ) The coating liquid wraps around the side is reduced.

<Condition 1>
The contact point cp of the blade 3 is within the range of 10 ° to 80 ° below the horizontal plane hp ₁ .
<Condition 2>
The contact angle ca of the blade 3 is within the range of 0 ° <ca ≦ 10 ° above the horizontal plane hp ₂ , and the tip of the blade 3 is inclined obliquely within this range, and the outer periphery of the coating roll (application roll 1) Contact the surface.

Note that the <Condition 2> is because the requirement that the blade 3 is inclined at an angle, some of the contact angle ca of the blade 3 does not include the case where a 0 ° relative to the horizontal plane hp _2. In order to clarify this, “0 ° <ca” is set in <Condition 2>.

Furthermore, in the coating apparatus M of the present embodiment, as described above, the tip of the blade 3 is cut only from one surface S ₁ of the blade surfaces S ₁ and S ₂ with a gradient of about 60 ° in one direction. configuration and inclined, the blade 3 adopts the configuration in which towards the blade sided S _1, the surface S ₂ that is not cut out of S ₂ are arranged so as to approach the outer peripheral surface of the application roll 1. For this reason, as shown by the arrow C in FIG. 3, the excess coating liquid scraped off at the tip of the blade 3 is in a downward direction that is reversed with respect to the direction of escaping due to the flow (the rotation direction R1 of the application roll 1). Because it is guided, it becomes easier to peel off and fall under its own weight. From this, the coating liquid wraps around from the both side edges of the blade 3 to the back surface (upper surface S ₂ ) further decreases, the swell of the scraping edge of the coating liquid (see FIG. 6) further decreases, and the scraping failure is reduced. High generation suppression effect.

The present invention is not limited to the embodiment described above. For example, instead of the coating roll (application roll 1) made of a plain roll, the present invention can also be applied to a method of scraping the coating liquid from a well-known plate cylinder having a concave portion used in intaglio printing such as gravure printing. The present invention can also be applied to a method in which the coating liquid is scraped off with a blade having no notch 9. Furthermore, the present invention, the coating liquid T ₀ with respect to the surface (coated surface) of the substrate K as shown in FIG. 5 (c), the not transfer directly applied, with a blade in contact with the coated surface It can also be applied to a method of scraping the coating solution.

FIG. 1 is an overall schematic diagram of a coating apparatus to which the present invention is applied. FIG. 2 is an explanatory diagram of the contact point and contact angle of the blade. 3A and 3B are explanatory diagrams of the inclination and gradient of cutting of the blade tip, wherein FIG. 3A is an enlarged view of a point where the blade is in contact with the application roll (coating roll), and FIG. 3B is an enlarged view of the blade tip. FIG. FIG. 4 is an explanatory view of a blade having a notch recess and the coating liquid before and after being scraped by the blade. 5A, 5B, and 5C are explanatory views of another embodiment of the present invention. FIG. 6A is an explanatory diagram of a scraping operation by a conventional doctor blade method, and FIG. 6B is a cross-sectional view taken along line BB shown in FIG.

Explanation of symbols

1 Application roll (coating roll)
2 Coating solution supply means 3 Blade 4 Backing roll (coating roll)
5 Substrate supply means 6 Rolled knife 7 Coating liquid reservoir 8 Pickup roll (coating roll)
9 Notch recess 10 Feeding roll 11 Winding roll ca Blade contact angle cp Blade contact point hp ₁ Horizontal plane passing through the center of the application roll (coating roll) ₂ Horizontal plane K including blade contact point K Strip-like base material M Application device R1 rotational direction _S 1, _{S 2} blade surface _T 0 _T 1 _{T 2} coating liquid in the rotational direction R2 backing roll (coating roll) application roll (coating roll)

Claims (5)

A coating roll for applying the coating liquid;
A coating liquid supply means for supplying a coating liquid to the outer peripheral surface or the surface to be coated of the coating roll;
A blade that contacts the outer peripheral surface or the surface to be coated of the coating roll and scrapes off the coating liquid;
The point of contact of the blade with the coating roll is in the range of 10 ° to 80 ° below a horizontal plane passing through the center of the coating roll;
The contact angle of the blade with the coating roll is in the range of more than 0 ° and 10 ° above the horizontal plane including the contact point of the blade, and the blade is inclined obliquely within the range. An applicator characterized by contacting a roll. The tip of the blade is cut from only one side of both sides of the blade and inclined in one direction, and the gradient of the inclination is in the range of 10 ° to 80 °.
The said blade is arrange | positioned so that the surface which is not cut among the both surfaces of the blade may approach the outer peripheral surface of the said coating roll. The coating device of Claim 1 characterized by the above-mentioned. The coating roll consists of a plain roll with no irregularities on the outer peripheral surface,
3. The coating apparatus according to claim 1, wherein the planar shape of the tip of the blade is a shape having at least one notch recess that does not scrape off the coating liquid. 4.   A coating method, wherein the coating liquid is scraped off from the outer peripheral surface or the coated surface of the coating roll using the coating device according to claim 1.   A coating method comprising: applying a coating solution in a streak pattern with substantially the same width as the notch recesses on the surface of a substrate using the coating apparatus according to claim 3.

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