KR20140042739A - Application element, device and method for applying a layer of a viscous material onto a substrate - Google Patents

Abstract

The present invention relates to an application element with multiple discharging channels (11) whose end in discharging openings (10) causes flow resistance applied to a combining material for each occurrence and, more specifically, to a device for applying a viscous material on a substrate where an application element includes one or more units affecting the flow resistance among connection openings of the application element, the discharging channels (11), and the discharging openings (10).

Description

APPLICATION ELEMENT, DEVICE AND METHOD FOR APPLYING A LAYER OF A VISCOUS MATERIAL ONTO A SUBSTRATE}

The present invention relates to an application element, an apparatus and method for applying a layer of viscous material onto a substrate, in particular a method for applying an adhesive layer or optical binding agent onto a plane made of glass or resin. In addition, the present invention relates to a preform.

In the manufacture of display systems, for example, a flat layer of binder is generally applied onto a substrate made of glass or plastic. In this case, there is a difficulty in obtaining the desired precision with respect to the size of the binder layer.

It is therefore an object of the present invention to improve an application element, an apparatus and method for applying a layer of viscous material onto a substrate.

The problem is solved by the features of claims 1, 9 and 10.

The key of the present invention is the use of a wide nozzle for the application of a layer with a plurality of outlet channels comprising outlet openings. The nozzle in this case comprises one or more means for influencing the flow and the pressure of the application material can be influenced by the means as intended in the region of the discharge openings.

As means for influencing the flow, in particular means for influencing the flow resistance of the outlet channels are used. As means for influencing flow, the intended adaptation and alteration of the geometry of the outlet channels over the width of the nozzle, in particular the intended adaptation of the length and / or cross section of the outlet channels over the width of the nozzle, may be used. Can be. Alternatively or in addition thereto, one or a plurality of means for influencing the flow may be arranged in the region before the discharge channels, in particular in the region of the pre-chamber adjacent the discharge channels inside the nozzle. .

What can be achieved by influencing the flow resistance between the connecting opening of the nozzle and the outlet openings of the nozzle is that a constant pressure distribution is obtained, especially in the region of the outlet openings. A constant pressure distribution can be achieved over the entire width of the nozzle. This allows the viscous material to be discharged evenly over the width of the nozzle. Therefore, the precision of the layer applied on the substrate can be improved.

Since the discharge openings of the nozzle are contiguous at narrow intervals in accordance with one aspect of the invention, independent jets of coating material, discharged from the discharge openings, merge after discharge from the nozzle, but especially before application onto the substrate. do. In other words, the material flows onto the substrate as a jet of material bonded to each other, in particular jets in the form of waterfalls or curtains. As a result, the uniformity of the thickness of the layer to be applied may be improved.

Since there are multiple discharge channels, the discharge of the coating material from the nozzle can be affected very accurately and / or flexibly over the entire width of the nozzle. Therefore, application of a layer of particularly uniform thickness is made possible and significantly improved.

The layer to be applied has a uniform thickness or at least substantially uniform thickness, in particular when it is already applied onto the substrate, in the transverse direction, ie over the width B of the nozzle. The variation of the average layer thickness is, in particular, at most 10%, in particular at most 1%, in particular at most 0.1%, as measured in the transverse direction. Therefore, the layers can be applied onto the substrate with high precision by the method according to the invention.

After application, the layer has a thickness in the range of 0.03 mm to 3 mm, in particular in the range of 0.05 mm to 1 mm, in particular in the range of 0.1 mm to 0.5 mm. Therefore, in the process according to the invention in particular very thin layers can be applied on the substrate.

According to one aspect of the invention the layer has a set thickness when applying the material over the substrate in the region between the nozzle and the substrate of the dosing device. In the direction perpendicular to the transverse direction the layer thickness decreases to zero to one side over the entire width of the nozzle, while the thickness of the layer is substantially constant in the opposite direction. Therefore, the layer has at least mostly uniform thickness immediately after application, ie has a desired layer thickness. When applying the material, no wave is formed in the application material which is displaced in front of the nozzle. As a result, the precision of the layer thickness is improved.

The number of outlet openings is at least 10, in particular at least 30, in particular at least 50. The discharge openings are in particular arranged at regular intervals, ie equidistant from each other. The precision can be significantly improved by the large number of outlet openings. The number of outlet openings can be up to 100, in particular up to 200, in particular up to 300, in particular up to 500, in particular up to 1000, in particular up to 2000, in particular up to 3000, in particular up to 5000, in particular up to 10000 have. The number may in principle be larger. Basically the number of outlet openings depends on the width of the nozzle. The line density of the outlet openings is in particular in the range from 0.1 mm ⁻¹ to 10 mm ⁻¹ , in particular in the range from 0.3 mm ⁻¹ to 3 mm ⁻¹ .

The width of the nozzle, ie the number of nozzle extensions in the transverse direction and the corresponding discharge openings, can preferably be adapted to the width of the substrate to be coated. Advantageously the nozzles can be exchanged for this purpose.

The discharge channels have flow path cross-sectional areas in the range of 0.05 mm 2 to 1 mm 2, in particular in the range of 0.1 mm 2 to 0.3 mm 2. These are especially formed as capillaries. Their diameter is in particular adapted to the viscosity of the material used as coating. In particular, they are formed so that the pressure is substantially uniform over their entire length when providing the coating material in the outlet channels.

In the discharge channels, the main pressure in particular in the region of the discharge openings can be controlled by the dosing device. It is particularly in the range of 0.15 MPa to 2 Mpa, in particular in the range of 0.2 MPa to 1 Mpa.

According to another aspect of the invention, the nozzle moves in the direction of movement when applying the material in connection with the substrate. This especially moves at a set speed. The direction of movement is particularly inclined, preferably perpendicular to the transverse direction.

The layer thickness is monotonically in the direction of travel starting from the region between the nozzle and the substrate when applying the material over the substrate so that the speed of relative motion between the nozzle and the substrate is chosen in particular depending on the viscosity of the coating material and the desired layer thickness. monotonously) decreases to zero. In particular, no material waveform occurs in the region in front of the nozzle in the direction of movement. As a result, the precision is improved with respect to the thickness of the layer to be applied.

This nozzle is formed such that the entire discharge openings are in one plane. The discharge openings are in particular arranged along a straight line. In addition, a nozzle may be arranged such that the plane of discharge openings extends parallel to the surface of the substrate being coated. Therefore, the entire discharge openings have the same distance to the substrate.

Advantageously one or more confining dams can be applied over the substrate prior to applying the material. The limiting dam is advantageous, in particular if the layer thickness is greater, in particular if the layer thickness is at least 0.5 mm, in particular at least 1 mm, in particular at least 3 mm. If the layer thickness is smaller, the limiting dam may not be used, especially for layer thicknesses of 1 mm or less, especially 0.5 mm or less, especially 0.3 mm or less, especially 0.1 mm or less. In principle, the fact is that the higher the viscosity of the coating material applied, the thicker the layers can be without a limiting dam. The area to be coated may in particular be limited by the limiting dam on the side, ie perpendicular to the transverse direction and preferably parallel to the transverse direction. The limiting dam in this case preferably has constant sizes, in particular a set cross section, in particular a set height. The height of the constraining dam is at least equal to the thickness of the application layer. In principle, the limiting dam may have a smaller height than the application layer. The dam is preferably exactly the same height as the application layer.

The application layer is in particular a layer consisting of one binder. This binder has in particular a refractive index which is adapted to the refractive index of the connecting components.

The coating material has a viscosity in particular in the range of ¹ mPas to 10 ⁴ mPas, in particular in the range of 300 mPas to 3000 mPas, in particular in the range of 500 mPas to 2000 mPas, in particular in the range of 800 mPas to 1200 mPas.

With the device according to the invention a layer can be applied particularly precisely on the substrate. It is possible to apply a layer having a predetermined size, in particular a layer having a set thickness, on the substrate very precisely.

Another object of the present invention is to improve a preform for multilayer displays. The problem is solved by the features of claim 15.

These advantages correspond to those described above.

Other advantages, features and details of the invention emerge from the detailed description of the embodiments with reference to the drawings.

The device according to the invention has the effect that a layer can be applied particularly precisely on the substrate and that the layer with a predetermined size, in particular a layer with a set thickness, can be applied very precisely onto the substrate.

1 is a schematic diagram of an apparatus for applying a binder onto a substrate in accordance with an embodiment of the present invention.
2 is a schematic cross-sectional view of a layer applied over a substrate according to a method not based on the present invention.
3 is a schematic cross-sectional view of a layer applied on a substrate at the time of application.
4 is a schematic cross sectional view of a layer applied on a substrate at a later point in time.
5 is a front view of an application element according to the invention for applying a binder on a substrate.
6 a perspective view of the application element according to FIG. 5;
FIG. 7 is a view of the application element along the line VII-VII of FIG. 5.
FIG. 8 is an enlarged view of region VIII of FIG. 7.
9 a view of the main body of the application element according to FIG. 5.
10 to 13 are views of the body according to FIG. 9 seen along lines XX, XI-XI, XII-XII and XIII-XIII.
14 is an enlarged view of the region XIV.
FIG. 15 shows further details of the outlet channels of the nozzle according to FIG. 9.
16 is a schematic diagram of exemplary results of a simulation method for simulation of pressure distribution in a binder in the region of the discharge openings of a nozzle.
FIG. 17 is another view of the nozzle according to FIG. 5 including an adapted length distribution of the discharge channels. FIG.

First, a dosing apparatus 1 for applying the binder 2 by dosing onto a substrate 3, for example, a glass plate or a synthetic resin plate, in particular a liquid crystal display (LCD), will be described.

The dosing device 1 comprises a dosing device 4 for supplying the binder 2 by dosing. The dosing device 4 is only schematically shown in the figures. It comprises a tank for the binder 2, a pressure generating element for generating the set pressure and a control device for controlling the pressure.

In a fluid connection, the dosing device 4 is connected with an application element which is formed as a nozzle 5 and directs the binder 2 towards the substrate 3. The nozzle 5 has a connection channel 6 for this purpose, which ends in the connection opening 7 opposite the dosing device 4. The connecting channel 6 of the nozzle 5 can be supplied with the dosing device 4 with a binder 2 having a set pressure p ₀ . The pressure p ₀ in the binder 2 in the region of the connecting opening 7 in the region of the nozzle 5 is in particular in the range of 150 kPa to 300 kPa.

This dosing device 4 is in particular an automatic doser.

When connecting the dosing device 4 to the nozzle 5, in particular in the region of the connecting opening 7, a filter 8 can be arranged preferably.

The dosing device 4 is connected to the transition chamber 9 by means of a connecting channel 6. The transition chamber 9 is arranged completely inside the nozzle 5. The transition chamber 9 can in particular be arranged at an angle with respect to the connecting channel 6. In the case of the embodiment shown in FIG. 6, the transition chamber 9 forms an angle of about 30 ° with the connecting channel 6. In general, the angle between the transition chamber 9 and the connecting channel 6 is in the range of 0 ° to 60 °, in particular in the range of 10 ° to 45 °, in particular in the range of 15 ° to 35 °.

On the side facing the connecting channel 6, the transition chamber 9 is connected to the discharge prechamber 20.

The discharge prechamber 20 leads to a plurality of discharge channels 11 at the outlet side. The discharge prechamber 20 therefore forms a connection chamber 6 connecting the connection channel 6 or the transition chamber 9 and the discharge channels 11. The discharge channels 11 each have a discharge opening 10 at the outlet side. The discharge channels 11 are formed such that the pressure p _a of the binder 2 is uniform in these discharge channels. The outlet channels are especially formed as capillaries, ie capillaries with small cross sections. The outlet channels 11 are described more precisely below.

The discharge free chamber 20 is completely covered by the cover 16.

The discharge free chamber 20 preferably has as small a volume as possible. Therefore, a larger amount of binder 2 can be avoided from accumulating in the nozzle 5. The volume of the discharge prechamber 20 is in particular smaller than 100 ml, in particular smaller than 30 ml, in particular smaller than 10 ml.

The discharge prechamber 20 has a width that increases in the flow direction, ie from the transition chamber 9 towards the discharge channels 11. To at least partially compensate for the increase in flow path cross-sectional area in this regard, the discharge prechamber 20 may have a decreasing depth in the flow direction, ie a decreasing free width. In this case, it is possible to form the discharge free chamber 20 whose depth is constant over the width of the nozzle 5. However, it is also possible to form an exhaust prechamber 20 having a variable depth over the width of the nozzle 5. Therefore, the flow resistance in the discharge free chamber 20 can be affected. The geometry of the discharge prechamber 20, in particular the geometry of the bottom wall of the main body 21 of the nozzle 5, in contact with the discharge prechamber 20, in other words the connection opening 7 of the nozzle 5 and the discharge channel. Between means 11 forms a means to influence the flow resistance. In particular, it is also possible to form the discharge prechamber 20 by profiling in the region directly in contact with the discharge channels 11. In this case it is possible to form the discharge free chamber 20 which has a smaller free height in the central region of the nozzle 5 than in the edge regions. The discharge free chamber 20 may in particular have a cross section which is formed concave on at least one side. The cross section of the discharge free chamber 20 may in particular be planar-concave or concave-concave. The shape of the concave boundary can preferably be explained by the cone region, in particular by an ellipse or parabola.

They especially have a constant cross section over their length l. This cross section is preferably at most 0.3 mm 2, in particular at most 0.15 mm 2. The cross sections of the individual outlet channels 11 have the same cross section, in particular the same, ie even if the outlet channels are different.

However, the length l of the discharge channels 11 is different. For example, as can be seen in FIG. 9, the discharge channels 11 are more in the central region of the nozzle 5 than the discharge channels 11 in the edge region of the nozzle 5 having a length l _r . It has a large length l _m . In the case of the embodiment shown in FIG. 9 the ratio l _m : l _r is about 2, which is generally in the range from 1.1 to 3, in particular in the range from 1.5 to 2.5. The distribution of the length l of the outlet channels 11 over the width B of the nozzle 5 can be explained by the cone region, in particular by an elliptical or parabolic.

The flow resistance of the outlet channels can be influenced by the length l of the outlet channels 11. Outlet channels 11 with a larger length l have a greater flow resistance with respect to the binder 2 than outlet channels 11 with a smaller length l. The length l of the outlet channels 11 therefore forms a means which influences the flow, in particular a means which influences the flow resistance. According to the invention, an appropriate change in the length l of the discharge channels 11 over the width B of the nozzle 5 affects the pressure distribution of the binder 2 in the region of the discharge openings 10. You can see that you receive. The distribution of the length l of the outlet channels 11 can be chosen such that the pressure in the binder 2 is the same in the region of the entire outlet openings 10. As a result, uniform discharge of the binder can be achieved.

As an alternative and / or additional means affecting the flow resistance of the outlet channels 11, the outlet channels can have different cross sections. However, all the discharge channels 11 having the same length l but different cross sections may be formed. In this case the cross section of the outlet channels in the central region of the nozzle 5 is smaller than the cross section of the outlet channels 11 in the side region of the nozzle 5.

In addition, it is also possible to influence the flow resistance through adaptation of the discharge prechamber 20 in the region adjacent the discharge channels 11. In other words, the free width of the discharge prechamber 20, ie the cross section, also forms a means to influence the flow resistance. Finally, separate means for influencing flow may be arranged in the discharge prechamber 20, in particular in the region adjacent the discharge channels 11. For example, you can think of the structure of the pore, which can influence the flow resistance. Structures of this kind can in particular be arranged interchangeably within the exhaust prechamber 20.

Of course, arbitrary combinations of means for influencing the flow described above are possible.

Discharge channels 11 may be formed which vary in cross section over the length l of the discharge channels. Therefore the flow behavior of the binder 2, in particular the flow resistance of the outlet channels 11, can be affected.

The discharge channels 11 are especially 0.05 mm 2 In the range of from 1 mm 2 to 0.1 mm 2 in particular It has a flow path cross-sectional area in the range of -0.3 mm <2>.

According to the invention it is possible to provide different sized outlet channels 11 in different nozzles 5 for binders of different viscosities. The nozzle 5 is particularly easily interchangeable with the dosing device 4.

The number of outlet openings 10 is at least 10, in particular at least 30, in particular at least 50. It may in particular be at least 100, in particular at least 200.

The discharge openings 10 are preferably arranged equidistant from each other. The outlet openings are arranged at a distance d in particular in the range of 0.3 mm to 1 cm, in particular in the range of 0.5 mm to 2 mm. The discharge openings are in particular arranged along a straight line. They preferably have a rectangular shape, in particular a square shape or a round shape, in particular a circular shape.

In particular, the substrate 3 and the nozzle 5 are formed and arranged together so that when the binder 2 is applied onto the substrate 3, the entire discharge openings 10 have the same distance as the substrate 3. . When applying the binder 2 on the substrate 3, the distance between the substrate 3 and the discharge openings 10 is in particular slightly larger than the layer thickness to be obtained. The distance between the substrate 3 and the discharge openings 10 when applying the binder 2 over the substrate 3 is in particular 0.01 mm to 1 mm, in particular 0.05 mm to 0.5 mm, in particular 0.08 mm, than the desired layer thickness. To greater than 0.12 mm. The distance ratio between the substrate 3 and the discharge openings 10 when applying the binder 2 on the substrate 3 is in particular at most 2, in particular at most 1.1, in particular at most 1.01, in particular at most 1.001.

The nozzle 5 is made of synthetic resin, aluminum or stainless steel, for example. The nozzle 5 may have a treated surface. The surface can be particularly rough or it can be polished. This in particular has a predetermined surface roughness. Therefore, the flow behavior of the binder 2 may be affected. This can in particular be CNC milled. It has a main body 21 and a cover 16 screwed to the main body. Therefore, in particular, the cleaning of the nozzle 5, in particular the discharge channels 11, is facilitated. As a result, in addition, the manufacture of the nozzle 5 becomes easy.

The seal 22 is disposed between the cover 16 and the main body 21. The seal 22 is formed as a planar layer. The seal is adapted to the shape of the cover 16. The seal 22 is in particular in contact with the cover 16 throughout. As an alternative to this the seal 22 may be arranged only in an area which is circumferentially closed in the periphery, ie in the area of the boundary edge 23 of the body 21 and along the front boundary edge of the nozzle 5. . Undesired lateral discharge of the binder 2 can be suppressed by the seal 22. Particularly guaranteed by the seal 22 is that the binder 2 is discharged only in the discharge openings 10 of the nozzle 5.

The cover 16 is in particular screwed to the boundary edge 23 of the main body 21 by a plurality of screws 24. In addition, the cover 16 may be screwed by a plurality of screws 24 arranged in parallel with the discharge openings 10. Therefore, the mechanical stability of the nozzle 5, in particular the cover 16, is improved.

In areas where the screws for screwing the cover 16 to the body 21 reach through the discharge free chamber 20, the binder 2 in the discharge free chamber 20 and to improve mechanical stability. Island shaped elements 25 are provided to influence the flow behavior of the &lt; RTI ID = 0.0 &gt; These island shaped elements 25 have a lenticular cross section. As a result, the formation of the vortex can be effectively avoided. In each case in the island-shaped elements 25 a thread 26 is arranged for receiving one of the screws 24.

The nozzle 5 comprises in particular a nozzle head 12 having a trapezoidal cross section. It has a width B in the transverse direction in the range of 1 cm to 100 cm, in particular in the range of 2 cm to 50 cm, in particular in the range of 4 cm to 25 cm.

The nozzle 5 can be arranged using the positioning device 13, which is only schematically shown in the figures with respect to the substrate 3. This can in particular be moved in relation to the substrate 3. The nozzle 5 can be moved with the positioning device 13 in relation to the substrate 3, in particular in the direction of movement 27. The direction of movement 27 is in particular transverse, in particular perpendicular to the transverse direction of the nozzle 5. The positioning device 13 may preferably have a control unit, with which the positioning of the nozzle 5 in relation to the substrate 3, in particular of the substrate 3 and the nozzle 5, Distance and / or speed of movement can be controlled.

The method for applying the layer 14 of binder 2 on the substrate 3 is described below. Binder 2 is a special example of a viscous material. The method is generally used to apply a layer 14 of viscous material onto a substrate 3. Firstly, the dosing device 1 and the substrate 3 described above comprising the binder 2 are provided. A predetermined amount of binder 2 is then applied onto the substrate 3 by the dosing device 1. In this case the binder is discharged from the discharge openings 10 of the nozzle 5 in the form of a number of independent jets. The number of such jets corresponds in particular to the number of outlet openings 10 of the nozzle 5. The jets discharged from the independent discharge openings 10 already merge before discharging onto the substrate 3, so that the size, in particular the flow path cross-sectional area of the discharge channels 11, in particular of the discharge openings 10, and in particular the neighboring The distance d of the discharge openings 10 is adapted to the viscosity of the binder 2 and / or the pressure p ₀ generated by the dosing device 4. These jets merge into a single, continuous, curtain-shaped material jet, especially before hitting the substrate 3.

Therefore, the binder 2 has a uniform thickness or at least mostly uniform thickness when applied over the substrate 3 over the entire width B of the nozzle 5. The deviations in thickness D in the transverse direction are in particular at most 10%, in particular at most 1%, in particular at most 0.1% of the average thickness of layer 14. The binder 2 has a mostly wavy surface although the surface structure 15 is slightly wavy at most when applied over the substrate 3. At most, the surface structure 15 present when applying the binder 2 on the substrate 3 is compensated within the joining time T.

In particular, it can be achieved for the nozzle 5 according to the invention that the binder 2 is uniformly applied on the substrate 3 over the entire width B of the nozzle 5. This improves precision over the alternative shown illustratively in FIG. 2, in which the binder is applied onto the substrate in the form of independent jets. In addition to the alternatives not according to the invention, which are exemplarily shown in FIG. 2, the flow resistances between the connection openings 7 of the nozzle 5 and the discharge openings 10 of the discharge channels 11 are different. By means of the means provided according to the invention, which affect, the same amount of binder 2 can be discharged from the entire discharge openings 10 of the nozzle 5.

The joining time T depends on the viscosity of the binder 2. It is preferably in the range of 1 to 20 seconds, in particular in the range of 3 to 10 seconds. In any case, the joining time T is much smaller than the time required for the curing of the binder 2. It is at least as small as factor 10, in particular at least as much as 50, than 2 required for curing the binder 2.

When applying the binder 2 over the substrate 3, the dosing device 4 is controlled such that the binder 2 is discharged from the discharge openings 10 of the nozzle 5 at _a set pressure p _a . . This pressure p _a is less than the pressure p _o in the region of the connecting opening 7. Especially _{p a: p o ≤ 1:} 1,5, in particular _{p a: p o ≤1: 2} , in particular _{p a: p o ≤ 1:} 3, in particular _a p: p _o ≤ 1: 5 is applied. This pressure p _a is particularly in the range of 100 kPa to 200 kPa.

The nozzle 5 is moved by the positioning device 13 in the direction of movement 27 with respect to the substrate 3 in order to apply the binder 2 onto the substrate 3. The nozzle 5 is in particular moved along a predetermined track, in particular inclined, preferably in a direction perpendicular to the transverse direction of the nozzle 5. The nozzle 5 is moved in the movement direction 27 at a set speed, in particular. It is possible to avoid the formation of a wave from the binder 2 in the region in front of the nozzle 5 in the direction of movement 27. The layer 14 has a thickness D, in particular in the direction of the movement 27, starting at the nozzle 5, which decreases monotonously. The thickness D of the layer 14 is particularly reduced to 0 mm, which monotonically decreases in the direction of movement, starting at the nozzle 5 over the entire width B of the nozzle 5.

One or more limiting dams 17 may be applied onto the substrate 3 prior to applying the binder 2 onto the substrate 3. The area on which the binder 2 is to be applied on the substrate 3 can be accurately set by the limiting dam 17. This limiting dam 17 can in particular be in contact with the region, on the end side, ie on the side and / or in front and on the rear, preferably in an annular shape. See DE 10 2011 005 379 and DE 10 2011 005 380 for details of the restriction dam 17 and the application of the restriction dam on the substrate 3.

The substrate 3 comprising the layer 14 of binder 2 is used in particular as a preform for the production of multilayer displays.

By means of the method according to the invention a layer 14 of generally uniform thickness D can be applied on the substrate 3 very precisely. Subsequently, another substrate 3 can be applied on this layer 14. This substrate can be, for example, a glass substrate or a synthetic resin substrate for covering the device. It may also be a display device, in particular a display or touch panel. The method according to the invention is particularly advantageous for the connection of any such substrate. This is particularly advantageous for applications where high precision is important. This belongs in particular to optical applications, in particular the manufacture of monitors.

The following describes the details and advantageous embodiments of the nozzle 5 with reference to FIGS. 15 to 17.

Since the embodiment of the nozzle head 12 shown in FIG. 15 corresponds to the embodiment shown in FIG. 9, reference is made to its description. As already described above, the discharge channels 11 have a greater length l _m in the central region of the nozzle 5 than the discharge channels having a length l _r in the edge region of the nozzle 5. In other words, the discharge channels 11 have a length l consisting of a constant portion l _r and a variable portion Δl over the width B of the nozzle. The length of the variable part Δl in this case can be explained by an elliptical envelope 28, as exemplarily shown in FIG. 15, over the width B of the nozzle 5.

This distribution of the length l of the outlet channels 11 over the width B of the nozzle 5 is simply an elliptical distribution of the length l corresponding to the cone area, in particular to the ellipse. Or varying.

The elliptical envelope 28 has in particular a first semi-axis ha ₁ which extends parallel to the row of the discharge openings 10. The length ha _{1 of} the first semi-axis is in particular half of the width B of the nozzle 5: ha ₁ = B / 2.

The elliptical envelope 28 can be described through the length ha ₂ of the second semi-axis. The second semi axis ha ₂ is in particular aligned parallel to the longitudinal direction of the discharge channels 11. Its length is its length, especially the length of the discharge channel (11) in the edge region of the nozzle (5) the length (l _m) and the nozzle (5) of the discharge channel in the central area 11 in the (l _r) Corresponds to the difference between: ha ₂ = l _m -l _r .

The length of the first semi-axis ha ₁ may be chosen to be greater than half of the width B of the nozzle 5. Especially B / 2≤ha ₁ ≤5B, especially B / 2≤ha ₁ ≤3B, especially B / 2≤ha ₁ ≤B, especially B / 2≤ha ₁ ≤0.7B is applied. Therefore, the length of the second semi-axis ha ₂ may also be selected differently. In particular 0.01 (l _m -l _r ) ≤ha ₂ ≤10 (l _m -l _r ), in particular 0.3 (l _m -l _r ) ≤ha ₂ ≤3 (l _m -l _r ), in particular 0.5 (l _m- l _r ) ≦ ha ₂ ≦ 2 (l _m −l _r ), in particular 0.8 (l _m −l _r ) ≦ ha ₂ ≦ 1.2 (l _m −l _r ), apply.

It will be appreciated that the pressure drop in the lateral region of the nozzle 5 is such that through such elliptic distribution or change in the length l of the discharge channels 11 over the width B of the nozzle 5. Can be compensated. The pressure distribution of the binder 2, which is applied as a point that can be particularly achieved through such length adaptation of the outlet channels 11 over the width B of the nozzle 5, is the outlet openings of the nozzle 5. Is constant in the area of (10). The binder 2 is discharged at a constant pressure, in particular from the discharge openings of the nozzle 5.

It is generally understood that the length of the second semi-axis ha ₂ should be selected so that the larger the nozzle 5 is, the larger it is. The width B of the nozzle 5 is in particular in the range of 1 cm to 300 cm, in particular in the range of 3 cm to 100 cm, in particular in the range of 10 cm to 30 cm.

In the embodiment according to FIG. 15 it can be seen that the pressure distribution in the binder 2 in the region of the outlet openings 10 of the nozzle 5 is substantially uniform, in particular even better for constant but constant applications. Can be. In particular a simulation method is provided for optimizing the length distribution of the outlet channels 11 over the width B of the nozzle 5. In this kind of simulation method the viscosity of the binder 2 is taken into account at set conditions, in particular at set temperatures, and the detailed geometry characteristics of the body 21, in particular the discharge free chamber 20, are taken into account.

Such a simulation is used to determine the pressure distribution of the binder 2 in particular in the region outside the nozzle 5, in the region of the discharge openings 10 of the discharge channels 11 or directly adjacent to it. . As exemplarily shown in FIG. 16, deviations of the actual pressure distribution 29 from the ideal isobar pressure distribution 30 can be detected using this simulation. As exemplarily shown in FIG. 16, such a simulation shows that, for example, the length distribution of the outlet channels 11 shown in FIG. 15 over the width B of the nozzle 5 is relative in the central region. It can be noted that the overpressure p ⁺ is causing relative negative pressure p ⁻ in the lateral regions of the nozzle 5. In this case the length distribution of the outlet channels 11 over the width B of the nozzle 5 can be adapted starting from the ellipse profile according to FIG. 15, as exemplarily shown in FIG. 17. For this purpose the length l of the outlet channels 11 can be large in the region of the overpressure p ⁺ . The length l of the discharge channels 11 in the region of the negative pressure p ⁻ can be shortened. The adaptations of the length l of the outlet channels 11 of the distribution shown in FIG. 15 are in particular in the range of several millimeters. These are especially at most 5 mm, in particular at most 3 mm, in particular at most 1 mm. They may be at least 0.1 mm, in particular at least 0.2 mm, in particular at least 0.3 mm, in particular at least 0.5 mm.

Claims (15)

As an application element 5 for applying a viscous material 2 onto a substrate 3, the application element is
a. One or more connection channels 6 terminating in the connection opening 7,
b. A plurality of outlet channels 11 terminating in the discharge openings 10, which are in fluid connection with the connection channel 6 by the connection chamber 20,
c. In the application element for applying a viscous material on a substrate, in which the flow resistance affects the viscous material 2 in the region between the connecting opening 7 and the respective outlet openings 10,
d. The application element 5 is characterized in that it comprises one or more means for affecting the flow resistances between the connection opening 7 of the application element 5 and the discharge openings 10 of the discharge channels 11. An application element for applying a viscous material onto the substrate. The method according to claim 1, wherein at least one means for influencing flow resistances is formed between the connection opening 7 of the application element 5 and the discharge openings 10 of the discharge channels 11. The pressure p _a prevails in the viscous material 2 coming out from 10, the pressure being applied to the viscous material over the substrate, characterized in that each pair is the same in the region of the other outlet openings 10. Element. The at least one of the preceding claims, which influences the flow resistances between the connection opening 7 of the application element 5 and the discharge openings 10 of the discharge channels 11. The means are in the following list, i.e. the length l of the outlet channels 11 which vary over the width B of the application element 5, the outlet channel which varies over the width B of the application element 5. The cross section of (11), the cross section of the connecting chamber 20 which is variable over the width B of the application element 5, the arrangement of independent means influencing the flow in the connecting chamber 20 and combinations of these alternatives And an application element for applying the viscous material onto the substrate. The discharge channels 11 according to any one of the preceding claims, wherein the discharge channels 11 have a length l, which length is variable over the width B of the application element 5 corresponding to the cone area. And an application element for applying a viscous material onto the substrate. 5. The application according to claim 1, wherein the application element 5 has a body 21 and a cover 16 screwed to the body. Element. 6. Application element according to claim 5, characterized in that the discharge channels (11) are milled in the body (21). 7. Application element for applying a viscous material on a substrate according to any one of the preceding claims, characterized in that the number of outlet channels 11 is at least 10, in particular at least 30, in particular at least 50. . 8. Viscosity on a substrate according to claim 1, characterized in that the discharge channels 11 have a flow path cross-sectional area in the range of 0.05 mm 2 to 1 mm 2, in particular in the range of 0.1 mm 2 to 0.3 mm 2. Application elements for applying the material. a. One or more dosing devices 4 for supplying the viscous material 2 by dosing and
b. For applying the viscous material 2 onto the substrate 3, comprising at least one application element 5 according to claim 1 for directing the viscous material 2 towards the substrate 3 to be coated. Device (1). a. Providing the substrate 3 to be coated,
b. Provision of the device 1 according to claim 9,
c. Applying a predetermined amount of coating material onto the substrate 3 using the apparatus 1,
d. A method for applying a layer (14) of viscous material (2) onto a substrate (3) comprising said steps, wherein the material (2) is discharged from the other outlet openings (10) in a set pressure distribution. Method according to claim 10, characterized in that the material (2) is discharged from the entire discharge openings (10) at the same pressure (p _a ). The material (2) according to any one of claims 9 to 10, wherein the material (2) is discharged from the discharge openings (10) in the form of independent jets, one of which is bonded before these jets strike the substrate (3). A method for applying a layer of viscous material onto a substrate, characterized by joining with a jet. The layer 14 according to claim 10, wherein the layer 14 is at most 10 when applying the material 2 over the substrate 3 in the region between the application device 5 and the substrate 3. And a uniform thickness in the transverse direction, with a% fluctuation, for applying a layer of viscous material over the substrate. 14. The layer 14 according to claim 10, wherein the layer 14 has a thickness D when applied over the substrate 3, the thickness starting in the application device 5 and moving direction 27. And monotonically decreasing and / or constant in the opposite direction of movement (27) starting from the application device (5). In particular as a preform for display, the preform
a. A substrate 3,
b. A layer 14 of binder 2, disposed over the substrate 3,
c. A preform in which a layer (14) is applied on the substrate (3) using the method according to any one of claims 10-14.

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