JPH06502597A - Apparatus and method for applying ink to a support - Google Patents

Abstract

This invention relates to an anilox printing apparatus (20) for depositing ink onto a substrate (23) in a predetermined pattern. The apparatus (20) has a reservoir (22) provided with a weir (30) so that ink (24) may continuously overflow the top or end of the weir (30) and be removed from the reservoir (22) in a controlled fashion while maintaining a constant backpressure of ink (24) in the reservoir (22). This arrangement provides the advantage that ink leakage and splashing caused by debris entering the nip associated with a doctor blade (26) held against the anilox roll (25) or by surface imperfections interfering with the seal formed by such a doctor blade (26) are eliminated. This also provides a printing apparatus (20) for complete coating of the periphery of the anilox roll (25) with ink (24) without a high pressure system.

Description

[Detailed description of the invention] Apparatus and method for applying ink to a support Field of the invention The present invention provides an apparatus and method for applying a liquid formulation to a support in a predetermined pattern. , in particular an apparatus and method for printing a liquid formulation on a support, More particularly, an improved printing device and method for use in flexographic printing. Regarding.

Background of the invention Printing and other means of applying liquid formulations such as inks onto a support are Well known in the technical field. Ink printing creates an aesthetically pleasing design on a substrate. It is done to create something. This kind of design is desired by consumers and printing To increase sales of products embodying the applied support. Also, liquids with desired properties The support may be coated with a similar formulation. For example, to increase hydrophilicity coated with surfactant and co-coated with adhesive to bond the two supports together. It may be coated with silicone to enhance the tactility.

Printing techniques such as flexography involve applying various liquid formulations to a moving support. A rotating device is used to do this. Such devices typically include a frame, An anilox roll that can be rotated around its axis is attached to this frame. , a liquid formulation to hold it until it is removed by an anilox roll. It has a server. In the prior art, the reservoir is open to the atmosphere.

One improvement over prior art devices is that the opening is such that a closed reservoir is formed. Multiple, typically two doctor blades in contact with the surroundings of the Nilox roll. It was to be established. No. 4, granted to Odom on August 7, 1990. 945.832, this configuration is open to the atmosphere. It is useful in splashing liquid formulations from the reservoir.

Many attempts have been made to properly position the closed reservoir relative to the anilox roll. It has been done. For example, in the Odom patent mentioned above, the reservoir is 01 placed at the bottom dead center of the U.S. Pat. No. 4,821,872, issued to Bruno on August 18, 1989, , a laterally mounted riser located at the three o'clock position of the anilox roll. teach the server. However, all of these closed containers do not allow pressure on liquid formulations. Requires complex sealing means to maintain force boundaries. For example, the Bruno mentioned above and U.S. Pat. No. 4.481 issued to Stone on April 15, 1986. No. 995 discloses a sealing device for the end of an anilox roll. These seals are necessary to maintain the pressure boundaries of the reservoir.

A further problem with such printing devices is that the In-running nip (in-running) in contact with the anilox roll Wear and adjustment of the doctor blade forming n1p). This doctor tab The lade is subject to wear from debris entering the nip.

Slight irregularities caused by such debris, daily wear and tear, and even damage to the reservoir pressure. breaking the force boundary and causing unexpected and undesirable loss of ink from the reservoir.

One solution to this problem was the rice grant granted to Pock et al. It was proposed in National Patent No. 4.938,133, and this patent includes Dr. A device that facilitates the removal, engagement, and disengagement of the It is shown. However, this measure is not entirely satisfactory. Toi This is because the original problem of doctor blade replacement and maintenance remains. Ru.

Further devices according to the prior art having either an open reservoir or a closed reservoir The problem is that removing the reservoir from its working position for routine maintenance requires a complex process. This means that equipment is required. Typically, maintenance requires drainage and associated significant downtime. Typically, the hinge The connected reservoir can be removed from its operating position to allow effective maintenance. There must be. One solution to this problem is as follows: November 7, 1989 As suggested in U.S. Pat. No. 4,878.427 to Waszczynski et al. The patent describes a device for removing anilox rolls without tools. location is disclosed. However, all the maintenance problems It cannot be corrected by replacing the module.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the problems associated with prior art printing devices. It is. In particular, it is an object of the present invention to eliminate the desirability of ink from the reservoir of a printing device. The purpose is to provide a means for minimizing unintentional bounce.

Furthermore, it is an object of the present invention to remove the ink from the reservoir without applying the ink onto the support. The purpose is to prevent ink from being wasted when printing.

Furthermore, it is an object of the present invention to eliminate shading stripes and blurring of the pattern formed on the support. Place the ink properly on the anilox roll to prevent this from occurring even at high moving speeds. The objective is to provide a more reliable means for coating. lastly , it is an object of the invention to minimize downtime when performing maintenance and to minimize downtime when performing maintenance. Almost no ink wastage occurs when the xroll is in the separation position improved separation of the reservoir and anilox roll from each other. The objective is to provide a device with

Summary of the invention The present invention provides a reservoir for containing ink and a reservoir for supplying ink to the reservoir. means to remove the ink from the reservoir and distribute the ink in a preselected pattern. For the means for applying the ink to the support and the means for removing and applying the ink. means for transferring the ink to the support and a reservoir without transferring the ink to the support. and an orifice for removing the ink in a controlled manner from the support. This is a device for coating. At least one boundary of the orifice is 1, ink Means are provided for removing the ink from the reservoir and applying the ink onto the support.

Further, the present invention provides a reservoir for containing ink and a reservoir for storing ink. means for removing and applying the ink to the support in a predetermined pattern; a second means for removing ink from the reservoir without applying it to the support; and means for creating back pressure in the reservoir. It is a device for The means for creating back pressure in the reservoir is the second ink drawer. It has at least one bounded orifice defined by an ejection means.

The means for removing ink from the reservoir and applying the ink to the support is Contains an anilox roll that is partially immersed in the server and is rotatable about its axis. It is better to In one embodiment, the orifice is substantially parallel to the axis of the anilox roll. The distal edges of the weirs arranged in rows have at least one boundary defined. another fruit In the example, the orifice is a weir located approximately parallel to the axis of the anilox roll. has at least one boundary defined by the ends of the

Furthermore, the present invention provides a reservoir for containing ink and a reservoir for supplying ink to the reservoir. means for removing the ink from the reservoir and applying it to the support. and at least one of the reservoir and the remainder of the device. means for separating the reservoir and the rest of the device from each other by An apparatus for applying ink onto a support, having the following features: The linear separation means is selected from the group consisting of screw jacks, pneumatic cylinders, or preferably hydraulic cylinders. It should be a selected component.

The present invention includes a step of providing a reservoir, a step of providing a support, and an ink reservoir. providing means for transferring from the carrier to the support; and providing an orifice in the reservoir with two boundaries to support the ink. including a method for printing on a body.

Ink is supplied to the reservoir and transferred from the reservoir to the support. Not migrated The ink is removed from the reservoir through an orifice. Not migrated Ink is drawn from the reservoir almost continuously and forms the boundaries of the reservoir. Overflowing through the top or one or both ends of the weir.

Brief description of the drawing The specification concludes with the claims particularly pointing out and distinctly claiming the invention. However, the present invention provides that the same parts have the same reference numerals and similar parts Further, by reading the following statement in conjunction with the accompanying drawings marked with “°” It is considered to be well understood.

FIG. 1 is a schematic side view of an open reservoir type printing device according to the prior art; Figure 2 shows the conventional model with broken lines showing the location where the reservoir and anilox roll are separated. 1 is a schematic side view of a chamber-fed closed reservoir printing device according to the technique; FIG. 3 is a schematic side view of the printing device according to the invention, and FIG. The apparatus of FIG. 3 having an orifice formed between the roll and the distal edge of the weir. It is an enlarged schematic side view, Figure 5 shows the reservoir and anilox roll in the working position, viewed from the direction of the weir. 5 is a partially sectional partially front view taken along line 5-5 in FIG. 4; Figure 6 shows the apparatus of Figure 5 showing the reservoir and anilox roll in a separated position; FIG. 7 is a schematic partial front view, and details of the linear translation means are omitted for clarity. An orifice is formed between the anilox roll and the end of the weir, FIG. FIG. 6 is an enlarged partial side view of a modification of the present invention.

Example As shown in FIG. 1, a prior art open reservoir type printing device 20 uses ink It has a supply roll 25° which is repeatedly immersed in the reservoir 22 of 4. The roll supplies ink 24 to an anilox roll 25 through a metering nip. stomach The plate cylinder 38 is coated with an anilock plate 24 having the desired and predetermined pattern around it. Transferred from Thrall 25. The pattern on the plate cylinder 38 is placed on the core of the plate cylinder 38. Preferably, it is formed by a removably attached design on the plate.

Plate cylinder 38 is juxtaposed with impression cylinder 40 to define a nip therebetween. The support body 23 is The desired pattern of ink 24 is applied to the support 23 from the plate cylinder 38 through the nip of the plate cylinder 38. It will be done.

Ink transferred from the anilox roll 25 to the plate cylinder 38 and then to the support 23 The amount of 24 corresponds to the diameter formed between the supply roll 25 Amount controlled by nip. Excess ink 24 is wiped off through this nip. Instead, it falls back into the reservoir 22 under the action of gravity.

This system has several problems. For example, supply roll 25° and aniro The ink 24 is measured through the nip formed between the ink roll 25 and the ink roll 25. Very inaccurate. An undesirable phenomenon that is unique to this device and for which no countermeasures can be taken. This is caused by the ink splashing when the ink 24 falls back into the reservoir 22. Ru. Splashing of ink 24 causes problems such as wastage of expensive ink 24, and This creates a cleanliness problem when the keys 24 fall to the floor and make the floor slippery. ink Other cleanliness issues may arise if 24 splashes onto the skin or clothing of nearby workers. It will be rubbed.

Referring to Figure 2, one attempt to solve these problems is shown in a room-supplied type This is done by the printing device 20. In the room-fed printing device 20, part of the boundary of the reservoir 22 is Two doctor blades 2 held in contact relationship with an anilox roll 25 6 and 26°. This boundary is where ink 24 is controlled from reservoir 22. Make sure you don't leave in a way you don't know.

This configuration eliminates the 25° supply roll and allows for the open reservoir configuration of Figure 1. Although this simplifies the configuration 20, other problems arise. For example, if the room-fed printing device 20 is The reservoir 22 must be pressurized, otherwise the anilox roll 25 Due to the boundary layer of air associated with the surroundings of the anilox roll 25, an The rock roll 25 cannot be completely covered with the ink 24. In this case, support The pattern to be printed on the body 23 is likely to become blurred or have light and shade stripes. Thus, Ri The pressure in the reservoir 22 must not be too low, otherwise the support 23 may be damaged. A pattern can be added.

If the pressure in the reservoir 22 is too high, the ink 24 26 and 26° or both, which is also desirable. This causes the ink 24 to splatter, which causes the above-mentioned ink 24 wastage problem. and cleanliness issues. If the pressure in the reservoir 22 is still too high, the Turblade 26 and 26°, or the end seal of reservoir 22, absorb the force of this pressure. It cannot be held and one of the components is blown out of the reservoir 22 and the pressure boundary is tear. In this case as well, undesirable splashing of the ink 24 occurs.

Furthermore, the in-running knit formed by the doctor blade 26° upstream of the device 20 The pool receives a large amount of waste. For example, dust and dirt found in many manufacturing environments. In addition, a wire ring or other material is passed from the support 23 through the plate cylinder 38 to the anilox roll. 25. This debris accumulates, and the doctor blade 26゜ and anilox slot It enters the in-running nip between the ball and the ball 25. Any debris that gets in should be treated as a doctor. The blade 26 is deformed and the ink 24 is discharged from the pressurized reservoir 22. Jump out. If not, debris will pass through the in-running nip and into the reservoir. 22 and potentially contaminate the contents of the reservoir.

Either the open reservoir printing device 20 of FIG. 1 or the chamber-fed printing device 20 of FIG. One problem with either is isolating the reservoir 22 from the rest of the device 20. It is. According to the prior art device 20, the reservoir 22 is mounted on the frame of the device 20. are connected.

As shown in FIG. 2, the hinged connection of reservoir 22 includes two pivot points 29 and requires a complex device 20 with a One pivot point 29 supports the reservoir 22. It is located at the base of the pivoting arm that holds the reservoir 22 and positions the reservoir 22 as a whole. Therefore, the pivoting arm is articulated.

A second pivot point 29° is provided on the pivot arm spaced apart from the first pivot point 29. It is being A pivot arm articulated from a second pivot point animates the reservoir 22. The pressure generated by the doctor blades 26 and 26 is seated on the rock roll 25. Seal the force boundaries as tightly as possible.

When it is necessary to perform maintenance on the apparatus 20, the ink 24 is drained from the reservoir 22. do. The reservoir 22 is then moved onto the anilox roll 2 using two pivoting arms. Pivot away from 5.

There are several problems that are unique to this device and for which no countermeasures can be taken. First, the lizard Since it takes time to drain the liquid from the bath 22, the device 20 is stopped for a long time, which increases manufacturing costs. do.

Additionally, when the reservoir 22 is tilted from its pivoted position to perform maintenance, residual The key 24 drains beyond the lowest edge of the reservoir 22 onto a device located below; The cleanliness and consequent waste problems mentioned above also arise.

Referring to FIG. 3, one embodiment of an apparatus 20 according to the present invention prints on a support 23 a reservoir 22 for holding ink 24 to be applied; 21; means for supplying at least the ink 24 held within the reservoir 22; The anilox roll 25 is rotatable about a partially immersed axis. . Anilox roll 25 is parallel to and in contact with plate cylinder 38, and their form a nip in between. The plate cylinder 38 is parallel to and juxtaposed with the impression cylinder 40. , forming a nip between them and ink 24 on the support 23 passing through this nip. is applied. The anilox roll 25, plate cylinder 38, and impression cylinder 40 collectively , for removing ink 24 from reservoir 22 and applying it to support 23. It serves as a means of removal and application. Components of device 20 that are not shown include support transfer means for transferring the body 23 to other components of the device 20; Means for rotating the xroll 25, plate cylinder 38, and impression cylinder 40 are included.

The device 20 includes a doctor that is parallel to and in contact with the sweetfish roll 25. - blade 26 parallel to and radially spaced from the anilox roll 25; It is preferable to further include a spaced weir 30. Doctor blade 26 and weir 3 0 forms the boundary portion of the reservoir 22 that holds the ink 24.

Conceptually, the device 20 has one (or more) reservoirs 22 in operation. It is considered that the ink supply section or inlet has an ink supply section or inlet. Ink 24 in reservoir 22 is divided into two ink removal channels. On the other hand, the ink extraction path is, of course, It is directed towards the support 23 and is applied onto the support in a predetermined pattern. Second The ink removal path is a controlled bleedoff of the ink 24. and is not transferred onto the support 23. The second ink take-off path has a plurality of secondary ink outlets. It is further subdivided into ink removal channels.

Referring to FIG. 4 and considering each component of the device 20 in more detail, the reservoir 22 is a leakproof material that holds and contains ink 24 used in printing or other application processes. It is a private room. The volume of the reservoir 22 is determined by the volume of the ring within the reservoir 22 where high shear forces act. This minimizes the residence time of the ink 24 at the boundary and prevents contamination of the reservoir 22 and To minimize ink loss in the event of leakage, a relatively small amount, approximately 7. Must be 6 to 23 (2 to 6 gallons). The reservoir 22 is , is very long in the axial direction of the anilox roll 25 compared to its cross-sectional area.

Reservoir 22 must be made of a material that does not leach contaminants into ink 24. Must be. Reservoir 22 is advantageously made of stainless steel, as is well known in the art. They are preferably made of stainless steel or glass-reinforced epoxy resin.

The ends of reservoir 22 are constructed with conventional contact seals, as is well known in the art. has been done. The appropriate seal is the rice gift granted to Stone on April 15, 1986. Preferably, it is made according to the teachings of National Patent No. 4.5111.995.

This patent is incorporated herein by reference for purposes of illustrating suitable end seals.

One boundary of the reservoir 22 is defined by a doctor blade 26 . doc Turblade 26 is tightly clamped at its proximal edge and its distal edge 2 8 is inside the window from about 15″ behind the bottom dead center to about 35° in front of the bottom dead center and extends outwardly so as to contact the anilox roll 25. Therefore, in The key 24 is prevented from leaking from the reservoir 22 when pressure is applied, and the rotation The ink 24 is appropriately wiped off from around the rotating anilox roll.

The doctor blade 26 is attached at a distal edge 28 of the doctor blade 26. must be held in an angular relationship to the tangent to the Nilox roll 25. stomach.

An angle of about 30'' to about 35'' has been found to be good. Doctor Bray The location of contact between the distal edge 28 of the door 26 and the circumference of the anilox roll 25 is The doctor blade is adjusted around the circumference of the anilox roll 25 within the window described above. 26 provides a constant angular relationship to the tangent around the anilox roll 25. must be adjusted to maintain For example, the distance of the doctor blade 26 The positioning edge 28 contacts the anilox roll 25 approximately 14 degrees behind the bottom dead center. If the doctor blade 26 is placed in an angular relationship of approximately 18° to the bottom of the reservoir 22, and maintain proper angular relationship to the tangent.

The other boundary of the reservoir 22 is constituted by a weir 30. The weir 30 has a proximal edge clamped and extending to a distal edge 32 juxtaposed with the periphery of the anilox roll 25. Bil.

For an anilox roll with an axial length of approximately 264 cm (104 inches) In other words, the distal edge 32 of the weir 30 is approximately 1.5 inches from the circumference of the anilox roll 25. radially by a distance of about 2.3 mm (0,060 inch to 0.090 inch) They are spaced outwardly and form the top of the weir 30. Distal edge 3 of weir 30 2 is chamfered as shown in the figure to reduce the horizontal area where debris accumulates. be.

As shown in FIG. 5, the length of the weir 30 is determined by the two ends 31 located on both sides. configured. The ends 31 of the weir 30 are preferably the same and the anilox roll 25 inside or outside of However, each end 31 of the weir 30 is It does not have to be located in the same position relative to each end 33 of roll 25. for example, The negative end 31 of the weir 30 is inside each end 33 of the anilox roll 25. Yes, the other end 31 of the weir 30 is outside each end 33 of the anilox roll 25. It is better to have it on the side. The arrangement of the end 31 of the weir 30 allows the ink 24 to be drawn from the reservoir 22. The end selected and used depends on the type of orifice 34 used for extraction. Determined by the type of seal.

Referring again to FIG. 4, the height of the distal edge 32 of the weir 30 is the height of the doctor blade 26. is higher than the distal edge 28 of the doctor blade 26 and the ink 24 is higher than the distal edge 28 of the It is important to maintain a constant hydrostatic head for the Nilox roll 25. . Hydrostatic head is the presence of a boundary air layer associated with the rotating anilox roll 25. Ink 24 may run out on the anilox roll 25. It is necessary to prevent blurring and shading stripes in the pattern to be printed on the support 23. be.

For the device 20 described herein, the distal edge 2 of the doctor blade 26 8 and the distal edge 32 of the weir 30 is about 2.5ei to about 15cm (1 6 inches) has been found to be suitable. Anilox throw As the circumferential speed of the wheel 25 increases, the height difference is similarly increased and the doctor blade It is necessary to maintain an appropriate head of ink 24 relative to surface 26 and to avoid destroying the air boundary layer. It is understood that this is not the case. If the boundary layer is not destroyed, the anillot There is a lack of ink in the xroll 25 and therefore the above-mentioned smearing of the pattern to be printed rays and dark and light stripes occur.

In the radial gap between the distal edge 32 of the weir 30 and the circumference of the anilox roll 25 Therefore, the orifice 34 that allows the ink 24 to flow from the reservoir 22 into the residual liquid path 27 is It is formed. The supplied ink 24 flows over the top of the weir 30 and into the reservoir 22. flows out from. This step is performed without transferring the ink 24 to the support 23. Controlled release and removal of ink 24 from reservoir 22 is provided.

One boundary of this orifice 34 is defined by the distal edge 32 of the weir 30; The other boundary of the orifice 34 is constituted by the extraction and application means. orifice The axial length of the anilox roll 25 is determined by the length of the anilox roll 25. determined by the length of The weir 30 is preferably, but not necessarily, a It is almost parallel to the Nilox roll 25. The axial length of orifice 34 and Therefore, as the cross-sectional area of the orifice 34 increases, the operation of the device 20 increases as the cross-sectional area of the orifice 34 increases. It is no longer dependent on the radial spacing from the periphery of the Nilox roll 25.

This configuration creates a horizontally oriented orifice with a high aspect ratio rectangular shape. system 34 is created.

Although there are other suitable shapes, this configuration includes an in-running nip dock. Eliminate the turret blades 26 and remove pressure boundaries in the reservoir 22 with line rings, dirt, and other debris. This has the advantage that loss of ink 24 due to disturbance of the ink is very unlikely to occur.

This is because no pressure boundary is maintained at this orifice 34.

Weir 30 and associated orifice 34 allow ink 24 to flow substantially continuously from reservoir 22. in a controlled manner without being transferred to the support 23. , provides means for controlling the ink supply means to the reservoir 22. in As used in conjunction with the key supply means, the weir 30 and associated orifice 34 , which constitute means for creating back pressure within the reservoir 22. used herein As shown in FIG. , the ink 24 is removed from the reservoir 22 in a "controlled manner". It is assumed that the It will be done. The rate of ink removal through this orifice is transferred to the support 23. Because the ink 22 is taken out for It is clear that it is.

The ink 24 taken out through this orifice 34 enters the residual liquid path 27. . The residual liquid passage 27 is preferably open to the atmosphere and, if desired, can recirculate the ink 24. The ink crosses the top of the orifice 34 and reaches the weir 30. and subsequent recycling of such ink 24 into the ink supply. will be held.

Ink 2 taken out from the reservoir 22 through the orifice 34 and the residual liquid path 27 4 is not printed or otherwise transferred to the support 23 (when taken out), Instead of being transferred, it is discarded and is not used or taken out through the residual liquid channel 27. Depending on whether waste ink 24 is to be disposed of or recycled, preferably , it is understood that it is recycled (to be later applied to the support 23). Should. Such ink 24 is called "untransferred ink."

Weir 30 and doctor blade 26 are arranged such that doctor blade 26 is downstream of weir 30. They are placed in such a relationship that

As used herein, the term "downstream" refers to the anilox slow Regarding the rotation direction of the anilox roll 25, more specifically, the rotation direction of the anilox roll 25. This relates to the arc portion formed by the reservoir 22 when measured. On the other hand, doku weir 30 It may be considered to be “upstream” of the turret blade 26.

Ink 24 is any liquid formulation that can be applied in a predetermined pattern onto support 23. be. As used herein, a "predetermined pattern" refers to the support 23 For any desired non-random arrangement of ink 24 applied thereon, small individual The entire pattern ranges from dots on the entire surface of the support 23 to complete coating of the entire surface of the support including combinations of As used herein, "ink" refers to any applied to the intended support 23 (even if the components of the ink evaporate). Relating to any liquid formulation that remains in the. Ink 24 should be visible to the naked eye, but You don't have to.

Preferably, the ink 24 is a flexo printing ink, and the anilox roll 2 Air entrained from the boundary layer associated with 5 causes the ink 24 to slow down. The desired pattern of dark and light stripes or Contains a defoamer to prevent leakage. Preferably, the ink 24 is applied to the second layer. Approximately 5 centipoise to approximately 10 centipoise measured over a period of approximately 14 seconds to approximately 22 seconds It has a dynamic viscosity of centipoise.

The ink 24 is preferably water-based, and the pigment size is about 5 μm to about 25 μm. It's good to have one.

Consider other rheological properties of the ink 24 such as rewettability, tack, and surface tension Must. These properties are such that the ink 24 and the anilox roll 25 Must be predetermined and established to be compatible. For example, in If the surface tension of the ink 24 is too large, apply the ink 24 to the anilox roll 25. It is not easy to take it out and apply it to the support 23 properly.

On the other hand, if the surface tension of the ink 24 is too small, the ink 24 can be It is not possible to properly remove the liquid from the reservoir 22 using the roller 25. Preferred ink 2 4 is Sun Chemical General Printing in Fort Lee, New Chassis. The Ink Department sells it as a water-based towel ink.

The device 20 includes ink supply means (not shown) for supplying ink 24 to the reservoir 22. without). The ink supply means for supplying the ink 24 to the reservoir 22 is , it must be possible to supply ink 24 at a switching rate of about 0.5 every 6 minutes. . For the apparatus 20 described herein, the preferred ink supply means is This is a positive displacement screw pump with a stop device. This pump stores ink 24 22 at a rate of about 3.8 to about 38 gallons per minute (1 to 10 gallons per minute), Preferably from about 5.7 to about 7.6 gallons per minute (1.5 to 2 gallons per minute). Continuously feed at speed.

Ink supply means for supplying ink 24 to reservoir 22 and distal edge of weir 30 An orifice 34 formed between the part 32 and the anilox roll 25 is a reservoir. operates in conjunction to create back pressure within the bar 22.

Thus, back pressure is the difference between the ink 24 supply rate and the ink 24 withdrawal rate, or It is created by the static water head created by the weir 30.

of ink 24 from an ink supply means for supplying ink 24 to reservoir 22; The inflow amount is determined by the amount of inflow that passes through the doctor blade 26 due to the rotation of the anilox roll 25. The ink 24 and the ink 24 taken out through the orifice 34 to the residual liquid path 27 are combined. As a result, the amount of ink 24 in the reservoir 22 is slightly added. When operating under constant conditions, although this is not common, the circle. Back pressure within reservoir 22 is required for successful operation of device 20.

Generally, as the peripheral speed of the anilox roll 25 increases, higher back pressure is required. be done.

Preferably, the ink supply means for supplying the ink 24 to the reservoir 22 is a reservoir 22. The reservoir 22 is continuously refilled with ink 24 to achieve the desired hydrostatic head as described above as much as possible. Maintain constant. Therefore, adding ink 24 to reservoir 22 in a batch process is not possible. , is generally not preferred and would otherwise maintain the desired hydrostatic head within the reservoir 22. difficult to understand. Ink supply means for supplying ink 24 to reservoir 22 In particular, the ink 24 is recirculated from the residual liquid path 27 and recycled to the reservoir 22. filtration to remove line rings, dirt, and other contaminants from the ink 24 when returned It will be understood by those skilled in the art that it is advantageous to have a system or particle separator. Let's go.

Ink 24 removed from reservoir 22 through orifice 34 is as described above. Since the ink is collected in the residual liquid channel 27, this ink does not splatter and causes cleanliness problems. No waste. The residual liquid channel 27 is located on the outside of the weir 30 and below the weir 30. Therefore, ink 24 passing through the orifice is easily trapped therein.

The residual liquid channel 27 advantageously surrounds the anilox roll 25 and the reservoir 22. I'm here. Preferably, the residual liquid passage 27 has a middle point with a middle height, and is aligned with the axis of the weir 30. The two lower points on the outside of either end of the weir 30 from the apex approximately coincident with the direction midpoint. It slopes downward to some extent. A slight slope of about 0.3' to about 1" is suitable. .

Each low point of the residual liquid path 27 is a gravity drainage liquid collection section 46 . The gravity drainage collection section 46 is , collect the ink 24 for disposal, batchwise or continuously, or Preferably, the ink 24 is recycled into the reservoir 22 and later transferred to the support 23 in a closed loop. an ink supply for supplying ink 24 to reservoir 22 to be transferred in a reservoir 22; Either continuously recirculates the ink 24 to the supply means.

A convenient way to recycle the collected ink 24 is to supply it to the reservoir 22. Such ink 24 is recirculated to the suction section of the positive displacement pump described above. It will be clear to those skilled in the art that this is the case.

Preferably, the ink 24 is at a height that coincides with the bottom of the reservoir 22 and extends beyond the bottom deck. from a supply line (not shown) at a lateral location not upstream of the reservoir 22. will be introduced in If this is not the case, the undesired A vortex is created and an ink-like foot is created on the anilox roll 25. Reservoir 24 ink The ink supply means for supplying the ink to the reservoir 22 has a volume of ink 24 in the reservoir 22. It should have a volume of about - times to about six times, preferably about four times to about six times. do not have.

Because the volume of ink 24 in reservoir 22 supplies ink 24 to reservoir 22 If the volume of the ink supply means is too large compared to the volume of the ink supply means, the ink in the reservoir 22 The residence time in the ink 24 is too long, causing shearing and foaming of the ink 24.

This results in incomplete coverage of the anilox roll 25 and the support 23. This is highly undesirable as it causes blurring and streaks in the pattern to be applied. .

Conversely, the volume of the reservoir 22 is the ink for supplying the ink 24 to the reservoir 22. If the volume is too small compared to the volume of the supply means, a rotating anilox roll 25 is immersed in ink 24 for a long enough time to be completely coated. The unsoaked, entrained air displaces a large or excessive amount of ink 24, and at this point Otherwise, the coating will be incomplete. Furthermore, the reservoir 22 must not be too shallow and must not be less than approximately 1ea (0.75 inch), otherwise the The reservoir 22 becomes sensitive to the standing waves of the ink 24, and in this case also the anilox roll 25 ink shortages occur.

The anilox roll 25 takes out the ink 24 from the reservoir 22 and ink 2. 4 to a support 23 in a metered manner. Honmei A process for taking out the ink 24 from the reservoir 22, as used in Toyonaka. The process and the process of applying the ink 24 onto the support 23 are collectively referred to as " It is called ``transition''. The anilox roll 25 prevents the ink 24 from transferring to the support 23. Should be used in conjunction with other components rather than being done directly . Ink 24 may be removed from reservoir 22 to other components such as plate cylinder 38. is indirectly transferred to the support 23.

The anilox roll 25 is generally cylindrical in shape and draws ink 24 from the reservoir 22. Attracted and removed by tube action, such ink 24 is later glued onto the support 23 and small cells are arranged around its periphery for migration and/or migration by capillary action. Ru. The anilox rolls 25 should be at least about 40 (1 inch) per IC11. laser-grooved cells with a minimum depth of approximately 10 μm (100 cells per It is best to have a surface finish with a ceramic coating. anilox The roll 25 has an "axis" extending through the center of the J cross section, and is centered around this axis. It can be rotated freely. The cells are spaced at an angle of approximately 45° from the axis of the anilox roll. It is oriented so that the

The anilox roll 25 preferably minimizes vibrations and therefore splashing of the ink 24. It is installed to be small. The diameter of an anilox roll is determined by its length and It should not be too small in comparison. The diameter of the anilox roll 25 is the anilox roll must be at least about 20% of the axial length of the roll 25; For speed, diameters with higher percentages are preferred.

Anilox roll 25 is partially immersed within reservoir 22 of ink 24. There is. As used herein, "partially immersed" means , at any time, a part of the periphery of the anilox roll 25 is covered with ink 24. Regarding the state where the anilox roll 25 is wetted and a part of the anilox roll 25 is exposed to the atmosphere. Ru. The surrounding wetted area is measured in the rotation direction of the anilox roll 25, It is located between the weir 30 and the doctor blade 26. In the atmosphere of Anilox Roll 25 The exposed portion is measured in the direction of rotation of the anilox roll 25 and treated with a doctor brush. It is located between the raid 26 and the weir 30.

The arc formed by the wetted area around the anilox roll 25 is an anilox The diameter of the roll 25, the surface finish of the anilox roll 25, and the anilox roll It is determined according to the circumferential speed of the roller 25. Generally, the circumferential speed of the anilox roll 25 (this of course depends on the diameter) or the anilox as the cell volume increases. In order to completely coat the periphery of the roll 25 with the ink 24, the reservoir 22 It is necessary to increase the residence time.

For the apparatus 20 described herein, a Each of the axially oriented lines has an ink dwell time of approximately 0.004 seconds to 0.035 seconds. Must have residence time. Approximately 38.3c++ (15,078 inches) straight For an anilox roll 25 with a diameter of about 305 m/min to about 915 m/min ( For circumferential speeds of 1000 to 3000 feet per minute, approximately 10.2 c■ A wetted length of 4 inches to 17.8 cm (17.8 cm to 1 inch to 1 inch) is suitable. I understand what you mean. As the circumferential speed of the anilox roll 25 increases, the wetted length increases. It becomes necessary to increase the size.

If desired for a particular removal or application step of ink 24, plate cylinder 38 may be It is provided parallel to and juxtaposed with the rock roll 25. The plate cylinder 38 is Preferably, it is in contact with the anilox roll 25 and is applied to the support 23. The ink 24 to be applied passes through two tubes. Plate cylinder 38 and Anilok The throttles 25 are gear-coupled so that they rotate at the same circumferential speed.

If desired, the impression cylinder 40 can be replaced with a plate cylinder, if desired for a particular removal or application step of the ink 24. 38 and is provided parallel to and juxtaposed with this. A support 23 passes through the impression cylinder. Configure the nip. The impression cylinder 40 presses the desired pattern onto the support 23 by the plate cylinder 38. A rotating anvil is constructed that maintains a predetermined resistance force against the support 23 when the to be accomplished. The support 23 passes through a nip formed between the plate cylinder 38 and the impression cylinder 40. and is compressed almost perpendicularly to the plane thereof, so that the ink 24 is applied to the support 23. A positive and fast transition takes place so that the desired pattern is completely applied to the support 23; is maintained on this support.

The anilox roll 25 and the plate cylinder 38 are the same in the nip formed between them. rotate in opposite directions so that a tangential velocity occurs in the direction. Similarly, the plate cylinder 38 and the impression cylinder 40 have tangential velocities in the same direction at the nip through which the support 23 passes. so that they rotate in opposite directions. Of course, anilox roll 25 and It will be clear to those skilled in the art that the impression cylinders 40 rotate in the same direction.

As used herein, "support 23" refers to a substantially flat planar web, sheet, single layer, multiple layers, or double-sided with ink on one of these sides. Regarding the laminate to which the key 24 is applied. The support 23 is preferably hydrophilic. It is good to have good absorbency. A particularly preferred support 23 is about 3.7 m2/m2. kg to approximately 13.4 kg (15 bonds to approximately 55 bonds per 2880 square feet) Toilet tissue, facial tissue, or base tissue with a basis weight of It has a cellulose fiber structure similar to that of a paper towel, and has a hardwood kraft fiber structure. Made from a mixture of kraft fibers of wood and softwood wood.

The support 23 applies the ink 24 in a substantially continuous pattern, in substantially interrupted patterns. It can be accepted in a turn, discontinuous pattern, or the whole can be coated with ink 24. will be logged. The apparatus 20 described herein applies ink 24 to one side of support 23. The second complementary device 20 can be used to print on the same side. The same pattern or a different pattern may be printed on the opposite side of the support 23. You should understand that.

Additionally, the apparatus 20 includes a method for transporting the support 23 against the anilox roll 25. or to any other means for removing and applying ink 24. Transport means (not shown) are provided for this purpose. Common, well-known and suitable means of transport A system of supply rolls and drawer rolls or an unwind stand and take-up Includes stand system. Preferably, the support 23 is such that the plate cylinder 38 can be wiped away. A constant tension is maintained on the support 23 without wrinkling or tearing. The nip composed of the plate cylinder 38 and the impression cylinder 40 is and passes at a speed equal to the circumferential speed of the impression cylinder 40.

Referring again to FIG. 5, device 20 includes reservoir 22 and the remainder of device 20; Specifically, Anilo Soxroll 25 and any of these components may be directly modified. They further include means for separating them from each other by linear translation. Lither The preferred means for separating the roll 22 and the anilox roll 25 from each other is to It is a linear translation device connected to the reservoir 22 below the sensor 22. This straight line The advancement device can be a screw jack, a pneumatic cylinder or, preferably, a hydraulic cylinder. It may have any known configuration, such as 42.

Hydraulic cylinders 42 mounted parallel and vertically to one of the reservoirs 22 It is best to use one at each end. Hydraulic cylinder 42 lowers reservoir 22 When moving away from the anilox roll 25, the Lisano<22 hydraulic cylinder 42 be secured to the bottom or side of the reservoir 22 to prevent it from rotating or pivoting relative to the must be fixed and firmly attached. The hydraulic cylinder 42 , it must be able to support the weight of the reservoir 22 when fully filled with ink 24. If either end of the lisano < 22 is at least They must be operated simultaneously so that there is no greater height difference.

Hydraulic cylinder 42 separates the top of reservoir 22 from the bottom of the anilox roll. must have enough stroke. Typically at least about A stroke of 6.4 cm (2.5 inches) is required.

It has a bore of approximately 6.4 cm (2.5 inches), and approximately 880 x 103 k per 1.2 Hydraulic cylinders rated for pressures of 1,250 pounds per square inch (1,250 pounds per square inch) 42 has been found to work well. Implementations described herein For example, manufactured by Oatman-Miller of No. 1 Mond, Indiana, A Type 7L hydraulic cylinder has been found to be suitable. Each hydraulic cylinder 42 Part No. L-243, manufactured by Peamar Precision Co., Fort Washington, Pennsylvania. Attaches to precision synthetic bushings 43, such as the bushings sold in numbers 8-24. It is good that it is The bushing 43 is parallel to the hydraulic cylinder 42. Securely attached to the frame of the device so that the

Referring to FIG. 6, with this configuration, the anilox roll 25 and the reservoir 2 Hinged connection and pivoting separation of the two from each other is prevented. by this, The depth of the ink 24 from the bottom of the reservoir 22 determined by the height of the doctor blade 26 can be maintained when the reservoir 22 is in the lowered position. This structure routine maintenance of the device 20 without draining the reservoir 22. You can do it even if you don't have it. For example, the doctor blade 26 can be replaced and the inspection of the gas roll 25 and lubrication of rotatably mounted components. Alternatively, the reservoir 22 and leftover liquid path 27 can be cleaned.

Occurs when separating the pivoted reservoir 22 from the anilox roll 25, Overflow of the ink 24 and therefore cleanliness problems and waste of expensive ink are avoided. It will be done.

Using this configuration, there is no draining process for the reservoir 22 when the device is stopped. Another advantage is that maintenance can be performed with short downtime.

Referring to the modification shown in FIG. 7, the weir 30 is in contact with the anilox roll 25. one or two orifices 34" at either end 31 of the weir 30 or consists of both of their ends. In such embodiments, the end 3 of the weir 30 1 is provided with the contact seal described above as described above. However, these The seal is provided with a notch at the top that opens into the residual liquid passage 27.

This forms an orifice 34° at each end 31 of the weir 30. One end of the weir 30 31 is opened to form an orifice 34°, and one end 31 of the weir 30 is sealed. Although it is possible to Preferably, both ends 31 are open to obtain balanced flow.

Such an orifice of 34° is suitable for dispensing and applying means, especially anilox rolls. 25 and a boundary 34' constituted by the weir 30. Not migrated The ink 24 that has not been transferred is brought into contact with the anilox roll 25. Unlike the above-described embodiment of FIG. is removed through these orifices 34' by flowing it axially. .

Several variations of the device 20 described and claimed herein are possible to those skilled in the art. It is also clear that. For example, weir 30 is anilox roll 2 5 may be radially spaced apart from the weir 30, with one end 31 of the weir 30 It may be open to the road 27.

This constitutes an ink extraction path with two orifices 34 and 34°, one One orifice 34' allows untransferred ink to flow in the axial direction, and one orifice 34' Rifice 34 allows untransferred ink to flow tangentially. Of course, weir 30 is anime The ends 31 of the weir 30 are spaced radially from the rocks roll 25 and are sealed. It may be open to the residual liquid path 27 instead of being closed. As a result, it was not migrated. Conceptually, the ink removal path is subdivided into three paths, and among these paths, two flow in axially opposite directions to each other, and one produces the tangential flow described above. vinegar.

It is also possible to remove the anilox roll 25 and place the gravure roll in that position. . Like the anilox roll 25, the gravure roll stores ink 24 in a reservoir. means for removing the ink from 22 and transferring the ink to the support 23 in a desired pattern; and be helpful. The only noticeable difference is that the desired pattern is placed around the gravure roll. It is engraved and is raised outward from the periphery of the anilox roll 25. That is.

Predictably, weir 30 and associated orifice 34 are filled with unmigrated ink. It need not be used to provide 24 secondary ink removal passages. For example, In the chamber supply type configuration shown in FIG. The ink 24 is controlled from the reservoir 22 in response to the inflow of the ink 24 from the supply means. An extraction tube to which a vacuum or other low-pressure device is attached is provided for extraction in a controlled manner. It's good to be kicked out. In some cases, the speed of ink 24 from the ink supply means The desired amount of ink 24 is applied using the hydraulic head pressure in conjunction with the extraction tube to support the desired amount of ink 24. taken almost continuously from the reservoir 22 in a controlled manner without migrating to the body 23. It is better to take it out.

If not, use room-supplied equipment! At 20, ink 24 is removed from the reservoir 22. A drainage line 46 is preferably provided at the bottom of the reservoir 22 for force drainage; Eliminates the need for separate vacuum or other low pressure extraction. Furthermore, ink 24 is reset. In order to remove the liquid from the server 22 at the desired speed, the extraction tube and drain line 46 are connected together. It will be clear to those skilled in the art that they may be used together. however, The configuration thus envisioned would have a pressure boundary at the reservoir 22 at the doctor blade 26. ° maintained and subject to bleaching caused by accumulated debris. There are drawbacks to the conventional technology.

international search report 1. , ++7. lA, l+,. l+N+ PCT/US 91107989I m-m1++ H1^++ll+li+N+ PCT/US 91107989

Claims (7)

[Claims] 1. a reservoir for containing ink and for supplying ink to said reservoir; an ink supply means, Remove the ink from the reservoir and apply the ink to the support in a pre-selected pattern. a dispensing-applying means for applying from said reservoir, preferably a removal-coating process for removing the ink and applying the ink to the support; cloth means centered on an axis partially immersed in said ink in said reservoir; a take-out and application means characterized by including an anilox roll which can be rotated freely; , a transport for transporting the support relative to said means for removing and applying ink; a means of transport; Removing ink from said reservoir in a controlled manner without transferring it to the support and an orifice substantially parallel to the axis of the roll. at least one boundary defined by the edge of a weir; A device for applying ink to a support. 2. The orifice is defined by an end of a weir that is substantially parallel to the axis of the roll. Device according to claim 1, characterized in that it has at least one border. 3. further comprising a doctor blade having a distal edge juxtaposed with the roll; a vector blade positioned downstream of the weir in an arc measured in the direction of rotation of the roll; delimiting said reservoir, preferably the height of said distal edge of said weir is More preferably, the distal edge of the doctor blade is higher than the distal edge of the doctor blade. Preferably, the device has an afterflow channel surrounding the doctor blade and the weir. 3. Device according to claim 1 or 2, characterized in that: 4. a reservoir for containing ink and providing ink to said reservoir at a first rate; an ink supply means for supplying ink; an anilox throw partially immersed in said reservoir and rotatable about its axis; le and transport means for transporting the support relative to the anilox roll; straightening at least one of the reservoir and the anilox roll; separating the reservoir and the anilox roll from each other by translation; Preferably, the separating means includes a screw jack, a liquid Vertical linear translation selected from the group consisting of pneumatic cylinders, and pneumatic cylinders. More preferably, the separation means is characterized in that it has moving components; An inking device characterized in that it consists of a hydraulic cylinder juxtaposed with each end of said device. A device for applying the substance to a support. 5. a reservoir for containing ink; and removing ink from the reservoir; Removal-applying means for applying ink to the support in a preselected pattern Preferably, the removal-applying means comprises an anilox roll. a removal-applying means having the characteristics of; passing ink from said reservoir through an orifice without applying ink to said support; a second ink take-out means for taking out the ink, said anilox roll and said second ink take-out means; having two ends in contacting relationship and disposed on opposite sides, said orifice having two ends disposed on opposite sides; The system is constituted by the anilox roll and at least one end of the weir. a second ink retrieval means having a feature that the second ink retrieval means is in said reservoir having an orifice with at least one boundary defined by a stage; and a back pressure forming means for creating a back pressure on the support. equipment for. 6. providing a reservoir; providing a support; providing a transfer means for transferring the ink from the reservoir to the support; and, the transition means providing an orifice in the reservoir having a boundary; process and supplying ink to said reservoir and transferring ink from said reservoir to a support; and removing untransferred ink from the reservoir through the orifice. Preferably, the ink is removed from the reservoir. The step of transferring to the holding body is providing an anilox roll and applying the anilox roll to the ink; a rotatable partial immersion step; providing a second roll substantially parallel to the anilox roll; rotating the second roll in contact with the anilox roll; transferring the support to and in contact with the second roll. The step of supplying ink to the reservoir and the transition The step of removing unfilled ink from the reservoir creates back pressure in the reservoir. by which the untransferred ink is removed from the reservoir. further characterized in that it is substantially continuously removed and preferably is not migrated. said step of substantially continuously removing ink from said reservoir in a controlled manner; , two placed on top and on both sides to control the depth of ink in the reservoir providing a weir having an end; flowing ink through at least one of the ends of the weir. A method for printing an ink onto a support, characterized in: 7. The method recycles untransferred ink back to the reservoir. 7. The method of claim 6, further comprising the step of: