Heating plate, heating device including heating plate, and method for manufacturing heating plate

Abstract

The present invention provides an improved heating plate (1) comprising a carrier plate (10) having a first main side (11) and a second main side (12) opposite the first main side. The carrier plate (10) is provided on the first main side (11) with a resistive heating layer (112) and with a plurality of buses (122) housed in respective V-shaped trenches (121) of the second main side (12) of the carrier plate (10). The V-shaped groove (121) tapers inwards in the direction of the first main side (11) towards the corresponding slit-shaped opening (13), and the bus (122) is electrically connected with the resistive heating layer (112) through the corresponding slit-shaped opening (13). The invention also provides a method for manufacturing the improved heating plate (1) and a heating device comprising the heating plate.

Description

Technical Field

[0001] The invention relates to a heating plate.

[0002] The invention further relates to a heating device comprising a heating plate.

[0003] The present invention further relates to a method of making a heating plate. Background Art

[0004] International patent application WO2021230746 discloses a transfer method for transferring a viscous functional material to a receiving substrate. The method provides a plate having a plurality of independently addressable resistive heating elements. When in use, the resistive heating element is used to heat the viscous functional material, thereby generating vapor pressure at the interface between the functional material and the plate. Thereby, the transfer of the viscous functional material from the plate to the target surface is caused. It is necessary to provide a heating plate that can be efficiently manufactured and a method for efficiently manufacturing a heating plate. Summary of the invention

[0005] A first object of the present invention is to provide an improved heating plate which can be manufactured efficiently.

[0006] A second object of the present invention is to provide a heating device comprising the improved heating plate.

[0007] A third object of the present invention is to provide an improved method for efficiently manufacturing a heating plate.

[0008] The improved heating plate according to the first object comprises a carrier plate having a first main side and a second main side opposite to the first main side. The carrier plate is provided with a resistive heating layer on the first main side. On its second main side, a plurality of V-shaped grooves are formed in the carrier plate, and corresponding buses are accommodated in the grooves. The V-shaped grooves taper inwardly in the direction of the first main side towards the corresponding slit-shaped opening, and wherein the bus is electrically connected to the resistive heating layer through the corresponding slit-shaped opening.

[0009] The improved heating plate can be obtained by using an improved manufacturing method. In which, the carrier plate of a material with anisotropic etching behavior, such as silicon, is provided. The carrier plate has a first main surface on its first main side and a second main surface on a second main side opposite to the first main side.

[0010] The method comprises etching a plurality of V-shaped grooves located on the second main surface of the carrier plate, the V-shaped grooves tapering inwardly in the direction of the first main side. Due to the anisotropic etching behavior of the material of the carrier plate, V-shaped grooves with well-defined wall angles can be formed in a simple etching process. For example, by using KOH or TMAH etchants, silicon with a 1-0-0 orientation is etched along the crystal structure, leaving a wall angle of 54.74 degrees.

[0011] The V-shaped grooves to be formed extend towards corresponding slit-shaped openings in the first major surface.

[0012] The method further comprises depositing a resistive heating layer on the first major surface and depositing corresponding bus bars in the V-shaped grooves, thereby providing corresponding electrical connections to the resistive heating layer via corresponding slit-shaped openings in the first major surface.

[0013] In one embodiment, the slit-shaped opening in the first main surface may be formed as part of the process of etching the V-shaped groove. In this case, the etching process is continued until the etchant has completely protruded from the carrier plate. In practice, it is possible that the carrier plate has a variable thickness. In this case, the slit-shaped opening formed in the first main surface also has different widths. That is, the slit formed by this process is relatively narrow at a position where the carrier plate is relatively thick compared to a position where the carrier plate is relatively thin. Therefore, an example of this method includes an additional step before the process of etching the V-shaped groove. In this additional step, the thickness profile of the carrier plate is measured, and an etching mask is provided on the second main surface, the etching mask having corresponding rectangular openings for a plurality of V-shaped grooves to be formed, so that the corresponding rectangular openings each have an appropriate width proportional to the thickness of the carrier plate, wherein the corresponding V-shaped grooves will be formed. Therefore, it is possible to obtain that the grooves formed by the etching process terminate at slits with the same width. It should be noted that if the thickness of the carrier plate varies in the length direction of the groove to be formed, the width of the opening may therefore vary in this length direction in a manner proportional to the thickness of the carrier plate.

[0014] In another embodiment of the method, the slit-shaped opening in the first main surface is formed in a separate process. This embodiment includes providing corresponding slit-shaped openings in the first main surface by anisotropically etching slit-shaped grooves in the first main surface of the carrier plate. In this embodiment, the depth of multiple V-shaped grooves etched is less than the minimum value of the thickness of the carrier plate. In this alternative embodiment, it is not necessary to know the exact thickness of the plate locally. If it is known that the thickness of the plate varies between a minimum value Dmin and a maximum value Dmax, the V-shaped groove can be etched with the same depth Dg that does not exceed the minimum value, and the slit-shaped groove can be etched with a depth that is at least equal to the difference between the maximum value Dmax and the depth Dg. And in this case, the corresponding electrical connection with the resistive heating layer extends to the corresponding bus in the V-shaped groove via the corresponding slit-shaped groove. It should be noted that such processes of etching the V-shaped groove and etching the slit-shaped opening can be performed in any order. However, it is best to etch the V-shaped groove first, and then use reactive ion etching to etch the slit from the other side one after another. It is best to etch the slit anisotropically so the slit width remains narrower.

[0015] In one embodiment, a plurality of buses are arranged to form corresponding bus layers conforming to the surface of the corresponding V-shaped grooves. Thus, electrical contact between the bus and the power supply can be established in an efficient manner, for example using spring pins. In an example, the bus layer is provided with an interface sublayer of a metal having a low thermal expansion coefficient on the side facing the carrier plate. The interface sublayer serves as an interface between the material of the carrier plate and the core of the bus. Thus, a high conductivity metal such as copper can be used for the core without being too restricted by thermal expansion coefficient requirements. Specifically in an example, the resistive heating layer is also formed by the metal having a low thermal expansion coefficient and a portion of the interface sublayer protrudes through the corresponding slit-shaped opening. The manufacturing process is simplified by using the same metal having a low thermal expansion coefficient for both the interface layer and the resistive heating layer.

[0016] In an embodiment, the bus layer comprises a contact sublayer of a metal with low contact resistance on the side facing away from the carrier plate. With only a thin sublayer of low contact resistance type metal, the electrical contact between the bus and the power supply is significantly improved.

[0017] In some embodiments, the resistive heating layer of the heating plate is patterned into a plurality of mutually insulated resistive heating bands, which extend upward on the other side of the plate transverse to the lateral direction of the bus, and one or more buses are interrupted at positions relative to the positions between successive heating bands. By using the interruption of the bus, mutually insulated bus portions are formed. The resistive heating layer can be controlled by pixel by supplying a driving voltage to a pair of bus portions in contact with a section of the heating band or to a continuous bus and a bus portion in contact with a section of the heating band.

[0018] In other embodiments, the resistive heating layer of the heating plate is patterned into a plurality of mutually insulated resistive heating sections, and one or more buses are interrupted at positions opposite to the positions at the boundaries between successive heating bands. By means of the interruption of the bus, mutually insulated bus sections are formed. The resistive heating layer can be controlled by supplying a driving voltage to a pair of bus sections in contact with the resistive layer sections, or to a continuous bus and a bus section in contact with the resistive heating layer sections.

[0019] Improved resolution for controlling thermal induction in the heating plate is achieved by an embodiment comprising a plurality of longitudinal bus portions insulated from one another. The plurality of longitudinal bus portions comprises the following:

[0020] a) respective groups of first longitudinal bus sections formed in a first plurality of first bus bars of a first polarity extending upwardly on a first side;

[0021] b) respective groups of second longitudinal bus sections formed in a second plurality of bus bars of the first polarity extending in a second lateral direction (y) transverse to the first lateral direction, the second bus sections respectively extending at central positions between respective bus sections of successive bus bars of the first plurality of first bus bars;

[0022] c) respective groups of third longitudinal bus portions formed in a third plurality of third buses of a second polarity opposite to the first polarity, wherein respective third buses extend upwardly on the first side between successive buses of the first plurality of first buses, and wherein respective groups of third longitudinal bus portions include respective pairs of third longitudinal bus portions of at least substantially the same length, respective pairs of third longitudinal bus portions having respective first ends proximate to successive second longitudinal bus portions of successive second buses and having respective second ends facing each other; and

[0023] d) corresponding groups of fourth longitudinal bus portions formed in a fourth plurality of fourth buses of the second polarity, wherein the corresponding fourth buses extend upwardly on the second side between successive buses of the second plurality of second buses, and wherein the corresponding groups of fourth longitudinal bus portions include corresponding pairs of fourth longitudinal bus portions of at least substantially the same length, the corresponding pairs of fourth longitudinal bus portions having corresponding first ends proximate to successive first longitudinal bus portions of successive first buses and having corresponding second ends facing each other.

[0024] In this embodiment, the resistive heater layer with improved resolution includes corresponding resistive heating layer segments, and the corresponding resistive heating layer segments are located between the corresponding pair of first longitudinal bus portions and the adjacent third longitudinal bus portions, and the corresponding pair of second longitudinal bus portions and the adjacent fourth longitudinal bus portions. In operation, the corresponding resistive heating layer segments can be selectively heated by supplying power to the corresponding pair of contact pins.

[0025] Typically, a heating plate is included as part of a heating device in a printer. The heating device includes, in addition to the heating plate, a support unit for supporting the heating plate on its second main side. The support unit includes corresponding spring loaded contact pins, also known as pogo pins, to provide corresponding electrical contacts with the bus. It is attractive if the support unit of the heating device is suitable for combination with various types of heating plates used by various consumers, such as standard heating plates configured to print large areas at a time or print on a line basis, heating plates suitable for pixel printing, and high-resolution heating plates capable of printing at four times higher resolution. In view of this consideration, a further improved embodiment of the heating plate is that it includes a plurality of longitudinal bus portions insulated from each other, the plurality of longitudinal bus portions including:

[0026] a) respective groups of first longitudinal bus sections formed in a first plurality of first bus bars of a first polarity extending upwardly on a first side;

[0027] b) respective groups of second longitudinal bus portions formed in a second plurality of second bus portions of the first polarity extending in a second lateral direction transverse to the first lateral direction, wherein each quad formed by a first bus pair of successive first bus portions and a second bus pair of successive second bus portions of the second bus portions define a respective region bounded by a respective pair of successive bus portions of each first bus of the first bus pair and a respective pair of successive second bus portions of each second bus of the second bus pair;

[0028] c) A corresponding cross-shaped bus is configured in each area to divide each area into four quadrants, wherein each quadrant includes a corresponding side portion of the resistive heating layer, and the corresponding side portion of the resistive heating layer is electrically connected to a corresponding branch of the cross-shaped bus and a corresponding bus portion in the bus defining the boundary of the area.

[0029] In a further improved embodiment of the heating plate, a first of a pair of longitudinal bus portions of the first bus has an end located between two adjacent bus portions of the first of the pair of second bus portions, the end defining the region, and a second of the pair of longitudinal bus portions of the first bus has an end located between a branch of the cross-shaped bus facing the first bus and a branch of the cross-shaped bus in the region directly adjacent to the bus. This improved heating plate also provides a four-fold higher resolution, but in addition, it is compatible with support units that are also compatible with standard line-addressable heating plates and pixel-addressable heating plates. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other aspects will be disclosed in more detail with reference to the drawings. Among them:

[0031] Figure 1 schematically shows a heating device comprising an embodiment of a heating plate and a support unit as claimed herein;

[0032] Figure 2 Shown in more detail Figure 1 A portion of an embodiment of a heating plate;

[0033] FIG. 3A to FIG. 3L The steps of an embodiment of an improved method of making an improved heating plate are shown;

[0034] FIG. 4A to FIG. 4C The steps of another embodiment of the improved method for making the improved heating plate are shown;

[0035] FIG. 5A to FIG. 5CAn example of a method is shown in which a viscous substance is deposited onto a target surface using a modified hot plate;

[0036] Fig. 6A and Figure 6B A first other embodiment of the improved heating plate is shown;

[0037] Fig. 7A and Figure 7B A second other embodiment of the improved heating plate is shown;

[0038] Fig. 8A and Figure 8B A third other embodiment of the improved heating plate is shown;

[0039] Fig.9A and Fig. 9B A fourth other embodiment of the improved heating plate is shown;

[0040] Fig. 10A and Fig. 10B A fifth further embodiment of the improved heating plate is shown. DETAILED DESCRIPTION

[0041] Unless otherwise indicated, the same reference numbers in the various drawings indicate the same elements.

[0042] Figure 1 The heating device is schematically shown, and the heating device comprises a heating plate 1 and a supporting unit 2 for supporting the heating plate 1. Figure 1 As shown, the heating plate 1 comprises a carrier plate 10 having a first main side 11 and a second main side 12 opposite to the first main side. The carrier plate 10 is provided with a resistive heating layer 112 on the first main side 11. A plurality of bus bars 122, 122a, 122b, ... are provided on the second main side 12, and the bus bars are accommodated in corresponding V-shaped grooves 121, 121a, 121b in the carrier plate 10. The V-shaped grooves 121, 121a, 121b, ... taper inwardly in the direction of the first main side 11 towards corresponding slit-shaped openings 13, 13a, 13b, and the bus bars 122 are electrically connected to the resistive heating layer 112 through their appropriate slit-shaped openings 13. The support unit 2 supporting the second main side 12 of the heating plate 1 comprises spring-loaded contact pins 21, 21a, 21b to provide electrical contact with the corresponding bus bars 122, 122a, 122b. In the example shown, the support unit 2 comprises additional support elements 22, 22a, 22b, 22c, ... which are not used for providing electrical contact.

[0043] In operation, a viscous functional material such as solder, curable conductive ink or curable electrically insulating ink is provided on the surface of the heating plate 1 at its first main side 11, and the heating plate 1 provided with the viscous functional material is arranged opposite to the target surface. In this configuration, one or more sections of the heating plate 1 are heated by supplying electricity between pairs of contact pins. Thereby, the viscous functional material is heated by the resistive heating layer 112, so that vapor pressure is generated at the interface between the functional material and the plate. The vapor pressure causes the transfer of the viscous functional material from the plate 1 to the target surface. In one embodiment, the additional support elements 22, 22a, 22b, 22c are composed of a material with good thermal conductivity so that a rapid cooling of the heating plate 1 is achieved after this operation.

[0044] Figure 2 A part of an embodiment of the heating plate 1 is shown in more detail. Figure 2 As shown, the resistive heating layer 112 extends in a continuous manner at the first main side 11 of the carrier plate 10. In the embodiment shown, the resistive heating layer 112 is coated with an insulating layer 113. Thus, the heating plate 1 is also suitable for printing conductive functional materials. Figure 1 As shown and Figure 2 As shown in detail, for the bus bar 122, a plurality of bus bars are arranged to form a corresponding bus bar layer conforming to the surface of the V-shaped groove 121 formed therein. Figure 2 As shown, reliable electrical contact between the bus bars 122, 122a, 122b and the spring pins 21, 21a, 21b can then be established in an efficient manner.

[0045] like Figure 2 In more detail, for the bus layer 122, an interface sublayer 1221 of a metal with a low coefficient of thermal expansion is provided on the side of the bus layer facing the carrier plate 10. The interface sublayer 1221 serves as an interface between the material of the carrier plate 10 and the core 1222 of the bus. Thus, a highly conductive metal such as copper can be used as the core without being too restricted by the requirements of the coefficient of thermal expansion. Suitable for this purpose are metals with a coefficient of thermal expansion (CTE) of less than 10 ppm / K, and preferably 5 ppm / K or less. Metals such as W, Mo, Cr, Ta are examples thereof. Alloys are also suitable, such as W90Ti10, which has 10% titanium to improve adhesion. In the example shown, the resistive heating layer 112 is also formed of the same low CTE metal as the interface sublayer 1221 for the bus 122, such as Mo. The electrical interconnect 131 between the bus 122 and the resistive heating layer 112 is also formed of the same low CTE metal. This facilitates the manufacturing process since in this case the electrical interconnect 131 between the bus bar 122 and the resistive heating layer 112 is formed as part of the deposited interface sub-layer 1221 .

[0046] exist Figure 2 In the example shown, the bus layer 122 also comprises a contact sublayer 1224 of a metal with low contact resistance on the side facing away from the carrier plate 10. With only a thin sublayer 1224 of a metal of low contact resistance type such as Au, the electrical contact between the bus and the power supply is significantly improved. Other metals suitable for this purpose are platinum, silver and other precious metals.

[0047] Figure 3A - Figure 3L An embodiment of a method for making a heating plate 1 is shown. Figure 3A As shown, in step S1, a carrier plate 10 of a material having anisotropic etching behavior is provided. An example thereof is a silicon substrate of 1-0-0 orientation, and its thickness may be in the range between about 30 microns and about 1000 microns. The carrier plate 10 has a first main surface at its first main side 11 and a second main surface at its second main side 12.

[0048] like Figure 3F As shown, in step S6, a plurality of V-shaped grooves 121, 121a, 121b, ... are etched on the second main surface of the carrier plate 10. The V-shaped grooves taper inwardly in the direction toward the first main surface. Due to the anisotropic etching behavior of the carrier plate 10, this can be simply achieved in a wet etching process using an etchant such as KOH or TMAH.

[0049] like Figure 3L As shown, in step S12, a resistive heating layer 112 is deposited on the first major surface. The resistive heating layer 112 is preferably a low CTE metal as described above.

[0050] Respective bus bars 122, 122a, 122b, ... are deposited in the V-shaped grooves 121, 121a, 121b, ..., thereby providing respective electrical connections 131 to the resistive heating layer 112 via respective slit-shaped openings 13, 13a, 13b, ... in the first major surface. Figure 3H and Figure 3K As shown, this process can be performed in multiple steps. In this example, an aligned sputtering mask 105 is used in step S8 to subsequently deposit a low CTE metal sublayer 1221 (such as Mo) and a seed layer (such as Cu) as a sublayer 1222, which forms the core of the bus 122, 122a, 122b. Then in a subsequent step S11, the sublayer 1222 is deposited on the seed layer by electroplating, and in this case, an intermediate layer 1223 and a sublayer 1224 of a metal with low contact resistance such as Au are subsequently electroplated. The intermediate layer 1223, in this case Ni, promotes the adhesion of the low contact resistance layer 1224.

[0051] In one example, the low CTE metal sublayer 1221, such as Mo, has a thickness of about 1500 nm, the sublayer 1222 of Cu forming the core of the bus 122 has a thickness of about 20 microns, the intermediate sublayer 1223 of Ni has a thickness of about 3 microns, and the low contact resistance sublayer 1224 of Au has a thickness of about 500 nm. Alternatively, it is contemplated to provide a bus composed entirely of low CTE metals. However, in this case, the bus would have poor electrical performance.

[0052] exist FIG. 3A to FIG. 3L In the embodiment of the method shown in FIG. 1 , the step S6 of etching the V-shaped groove is preceded by the steps of: FIG. 3C to FIG. 3ESteps S3 to S5 are shown. In step S3, an etching mask layer 102 such as silicon nitride (Si3N4) is deposited on the main surface of the carrier plate. In step S4, the thickness profile of the carrier plate 10 is measured, and in the subsequent step S5, an etching mask 103 is provided by photolithographically processing the etching mask layer on the second main surface so that corresponding substantially rectangular openings for a plurality of V-grooves 121, 121a, 121b, ... are formed. The rectangular openings have an appropriate width proportional to the thickness of the carrier plate 10, where the corresponding V-grooves 121, 121a, 121b, ... are to be formed. For example, if the thickness of the carrier plate 10 measured at the position where the V-grooves 121, 121a, 121b are to be formed is Dx, Dxa, Dxb, then the widths Wx, Wxa, Wxb of the openings at this position are c.Dx+d, c.Dxa+d and c.Dxb+d. Wherein c is a constant (2 / tgα) which is determined by the anisotropic properties of the material of the carrier plate 10, and d is the required width of the slit to be formed at the first main surface. For example, if the carrier plate is a 1-0-0 silicon wafer, the grooves formed in the etching process taper inward at an angle of 54.74°. This step can be used to obtain that the grooves formed by the etching process terminate at slits of the same width despite the thickness variation of the carrier plate. In this example, it is assumed that the thickness of the carrier plate varies only in the direction from left to right in the figure. In fact, thickness variations may also occur in directions orthogonal thereto. In this case, the opening in the etching mask 103 is not completely rectangular, but has a width that varies according to the depth variation in the orthogonal direction. Therefore, the width Wx(x,y) of the opening in the etching mask 103 is equal to c.Dx(x,y)+d, where (x,y) is the position on the second main surface. In an optional step S2, after the carrier plate 10 has been provided in S1 and before further steps are performed, an electrical insulator layer is provided on the surface of the carrier plate 10. Optionally, the electrical insulator layer is also provided S7 after etching the plurality of V-grooves in S6, S6A. These steps S2, S7 are advantageous if the carrier plate 10 is not a good electrical insulator. Preferably, the electrical insulator layer has a low thermal conductivity. Figure 3B and Figure 3G The optional steps S2, S7 shown in are best performed by thermally oxidizing the carrier plate 10. The thermal oxidation effectively provides the electrically insulating layers 101, 104 with low thermal conductivity.

[0053] Figure 4A , Figure 4B , Figure 4C Another aspect of the method is shown, in which it is possible to Figure 3DIn the case of the thickness profile measurement S4, a slit with uniform width is obtained. It is sufficient to know between which boundaries the thickness varies. In addition, the width of the opening in the etching mask 103 does not need to be determined by Figure 3E The step S5 shown is very accurately determined based on the position on the carrier plate 10. As described above, using Figure 3A and Figure 3C Steps S1 and S3 described in provide the board 10, optionally with an intermediate step S2.

[0054] In this case, it is sufficient that the edge mask 103 formed in the etching mask layer 102 in step S5A has a rectangular opening with a uniform width Wx. Figure 3F In step S6 shown in FIG. 1 , this alternative method includes step S6A of etching a plurality of V-grooves 121, 121a, 121b using an etchant such as KOH or TMAH. Figure 3F In contrast to step S6, the depth of the grooves etched is less than the thickness of the carrier plate 10. Figure 4C In the separate step S6B shown, the first main surface of the carrier plate 10 is anisotropically etched, for example using a reactive ion etching process, to form slit-shaped openings 13, 13a, 13b, ... in the first main surface. In the example shown, after etching the V-shaped grooves 121, 121a, ... in step S6A, the slit-shaped openings 13, 13a, ... are etched in step S6B, although these steps can also be reversed, but using the example Figure 4B , Figure 4C The best results can be obtained in the order shown in . If it is known that the thickness of the plate varies between a minimum value Dmin and a maximum value Dmax, the V-groove can be etched with the same depth Dg not exceeding the minimum value, and the slit-shaped groove can be etched with a depth at least equal to the difference between the maximum value Dmax and the depth Dg. Therefore, since the separate step S6B forms a slit of predetermined width for electrical connection between the bus and the band between the resistive heating layer 112, regardless of the thickness variation of the plate 10, the width variation of the pattern in the etching mask does not have to closely correspond to the thickness variation of the plate. The opening areas in the etching mask can have substantially the same shape. Slight variations in the width of the opening areas will not affect the width of the slits.

[0055] Steps S5, S6A, S6B described herein may be followed by steps Figure 3L The step S12 of depositing the resistive heating layer 112, and after depositing the bus bar in one or more steps.

[0056] Figure 5A , Figure 5B , Figure 5C The subsequent steps S13, S14, and S15 are shown. Figure 5A In step S13 shown, the heating plate 1 or its variant obtained using the first method or the second method is combined with a support unit 2 to form a heating device. The support unit 2 includes corresponding spring-loaded contact pins 21 to provide corresponding electrical contact with the bus. Figure 5B In step S14 shown, a patterned layer of adhesive substance 7, such as curable conductive ink, is provided at the first main side 11 of the heating plate 1, for example by stencil / screen printing using a printing mask 5 and a doc-torblade or squeegee 6. Figure 5C In step S15, the contact pins 21 of the support unit provide power to the resistance heating layer 112, and then the surface of the resistance heating layer 112 is resistively heated, thereby generating about 50 to about 500 kW / cm 2 and heat fluxes in the range of about 0.2 to about 2 J / cm 2 Thus, the viscous substance 7, 7a, 7b is transferred to the surface of the target.

[0057] Fig. 6A , Figure 6B Aspects of the first embodiment of the heating plate 1 are shown in more detail. Fig. 6A A bottom view of the heating plate, ie a view of the second main side 12 , is shown. Figure 6B The sections are shown in more detail. In this embodiment, the bus extends over the entire size of the board. The linear sections of the board can be heated independently of each other. For example, a linear section can be heated individually by supplying power between bus 122L- with contact pin 21L- and bus 122L with contact pin 21L. Another linear section can be heated individually by supplying power between bus 122L with contact pin 21L and bus 122L+ with contact pin 21L+.

[0058] Fig. 7A , Figure 7B Aspects of a second embodiment of the heating plate 1 are also shown in a bottom view, wherein Figure 7B The sections of the heating plate are shown in more detail. In this example, the resistive heating layer 112 is patterned into a plurality of mutually insulated resistive heating bands 112a, ..., 112k, ..., 112n extending upward on the other side of the plate transverse to the lateral direction of the bus 122, 122a, ..., 122l, ..., 122m. In addition, the bus is interrupted at the relative position of the position between the heating bands that are consecutive to each other. By utilizing the interruption of the bus, mutually insulated bus sections 122lk-, 122lk, 122lk+ are formed. In this embodiment, the resistive heating layer can be controlled by pixel by supplying a driving voltage to a pair of bus sections in contact with the sections of the heating band or to a continuous bus and a bus section in contact with the heating band sections.

[0059] Fig. 8A , Figure 8B Another embodiment is shown again in a bottom view, wherein: Figure 8B The sections of the heating plate are shown in more detail. In this embodiment of the heating plate 1, the resistive heating layer 112 is patterned into a plurality of mutually insulated resistive heating sections A, B, C, D, E, F, ..., and one or more buses are interrupted at positions relative to the positions at the boundaries between successive heating bands. By utilizing the interruption of the bus, mutually insulated bus sections 122lk-, 122lk, 122lk+ are formed. The resistive heating layer 112 can be controlled by supplying a driving voltage to a pair of bus sections in contact with the resistive layer sections, or to a continuous bus and a bus section in contact with the resistive heating layer sections.

[0060] Fig.9A , Fig. 9B Another embodiment is also shown in bottom view. Fig.9A shows a portion of a heating plate, and Fig. 9B The details are shown. This embodiment of the heating plate comprises a plurality of longitudinal bus portions which are insulated from each other. These comprise respective groups of first, second, third and fourth longitudinal bus portions as defined in more detail below.

[0061] Respective groups of first longitudinal bus portions 122bc, ..., 122dc, ... are formed in a first plurality of first bus bars 122, 122b, 122d, ... of a first polarity extending in a first lateral direction (x).

[0062] Respective groups of second longitudinal bus portions 126bb, 126bd, ..., 126db, 126dd are formed in the second plurality of buses 126, 126b, 126d, ... of the first polarity extending in a second lateral direction (y) transverse to the first lateral direction. The second bus portions extend at the center positions between the respective bus portions of the consecutive buses in the first plurality of first buses, respectively.

[0063] Respective groups of third longitudinal bus portions 122cb, 122cc are formed in a third plurality of third buses 122a, 122c, ... having a second polarity opposite to the first polarity. The respective third buses extend in the first lateral direction (x) between successive buses of the first plurality of first buses, and the respective groups of third longitudinal bus portions include respective pairs of third longitudinal bus portions of at least substantially the same length, the respective pairs of third longitudinal bus portions having respective first ends close to successive second longitudinal bus portions of successive second buses, and having respective second ends facing each other.

[0064] Respective groups of fourth longitudinal bus portions 126cb, 126cc are formed in the fourth plurality of fourth buses 126a, 126c, ... of the second polarity. The respective fourth buses extend in the second lateral direction between successive buses in the second plurality of second buses, and the respective groups of fourth longitudinal bus portions include respective pairs of fourth longitudinal bus portions of at least substantially the same length, the respective pairs of fourth longitudinal bus portions having respective first ends proximate to successive first longitudinal bus portions of successive first buses, and having respective second ends facing each other.

[0065] The resistive heating layer includes corresponding resistive heater layer segments 112cbx, 112cby, 112ccx, 112dcy, and the corresponding resistive heater segments are located between the corresponding pairs of first longitudinal bus portions and the adjacent third longitudinal bus portions, and between the corresponding pairs of second longitudinal bus portions and the adjacent fourth longitudinal bus portions.

[0066] In operation, respective resistive heating layer sections 112cbx, 112cby, 112ccx, 112dcy are selectively heated by supplying power to respective pairs of contact pins. For example, by providing power to the pair of contact pins 21ccy and 21bdy, the heating layer section 112ccx can be resistively heated.

[0067] Fig. 10A , Fig. 10B Yet another embodiment is also shown in bottom view. Fig. 10A shows a portion of a heating plate and Fig. 10B Display its details.

[0068] like Fig. 10A , Fig. 10B The embodiment of the heating plate 1 shown comprises a plurality of longitudinal bus portions which are insulated from one another. These comprise respective groups of first longitudinal bus portions and respective groups of second longitudinal bus portions.

[0069] Respective groups of first longitudinal bus portions are formed in a first plurality of first bus bars 122, 122a, 122b, ... of a first polarity extending in a first lateral direction (x).

[0070] Respective groups of second longitudinal bus portions are formed in a second plurality of second bus bars 126, 126a, 126b, ... of the first polarity extending in a second lateral direction (y) transverse to the first lateral direction (x).

[0071] Each quad formed by first bus pairs of successive first buses and second bus pairs of successive second buses defines a corresponding area Aaa, which is bounded by corresponding pairs of successive bus portions of each first bus of the first bus pairs 122, 122a and corresponding pairs of successive second bus portions of each second bus of the second bus pairs 126, 126a.

[0072] The heating plate further includes a corresponding cross-shaped bus 128aa of a second polarity opposite to the first polarity arranged in each region, which divides each region into four quadrants Aaa1, Aaa2, Aaa3, Aaa4.

[0073] Each quadrant includes a respective side portion of the resistive heating layer electrically connected to a respective branch of the cross-shaped bus and a respective one of the bus portions 122_2, 126a_2, 122a_1, 126_1 of the busses 122, 126a, 122a, 126 defining the boundaries of the area Aaa.

[0074] The first one 122_1 of the pair of longitudinal bus portions 122_1, 122_2 of the first bus 122 has an end portion located between two adjacent bus portions of the first one 126 of the second bus pair, the end portion defining the region. The second one 122_2 of the pair of longitudinal bus portions 122_1, 122_2 of the first bus 122 has an end portion located between a branch of the cross-shaped bus 128aa facing the first bus 122 and a branch of the cross-shaped bus in the directly adjacent region facing the bus.

[0075] like Fig.9A , Fig. 9B In the embodiment, Fig. 10A , Fig. 10B The improved heating plate provides four times higher resolution, but in addition, the improved heating plate can be combined with a support unit that is also compatible with standard line-addressable heating plates and pixel-addressable heating plates.

[0076] In the scope of the patent application, the term "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfil the functions of several items listed in the claims. The mere fact that certain measures are listed in mutually different claims does not indicate that a combination of such measures cannot be used to advantageous purposes. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. A heating plate (1), comprising: A carrier plate (10) having a first main side (11) and a second main side (12) opposite the first main side, The carrier plate (10) is provided with a resistance heating layer (112) on the first main side (11), and a plurality of bus bars (122) are provided on the second main side (12), and the plurality of bus bars (122) are accommodated in corresponding V-shaped grooves (121) of the carrier plate (10), and the V-shaped grooves (121) are tapered inwardly in the direction of the first main side (11) toward corresponding slit-shaped openings (13), and wherein the bus bars (122) are electrically connected to the resistance heating layer (112) through the corresponding slit-shaped openings (13).

2. The heating plate (1) according to claim 1, characterized in that The plurality of bus bars (122) are arranged as corresponding bus bar layers conforming to the surfaces of the corresponding V-shaped grooves (121).

3. The heating plate (1) according to claim 2, characterized in that The bus layer on the side facing the carrier plate (10) comprises an interface sublayer (1221) of a metal with a low thermal expansion coefficient.

4. The heating plate (1) according to claim 3, characterized in that The resistive heating layer (112) is also formed of the metal having a low thermal expansion coefficient, and wherein a portion of the interface sublayer (1221) protrudes through the corresponding slit-shaped opening (13).

5. A heating plate (1) according to any one of the preceding claims, characterised in that The bus layer on the side facing away from the carrier plate (10) comprises a contact sublayer (1224) of a metal with low contact resistance.

6. A heating plate (1) according to any one of the preceding claims, characterised in that The resistive heating layer (112) is patterned into a plurality of mutually insulated resistive heating bands (112a, 112k, 112n), wherein the resistive heating bands (112a, ..., 112k, ..., 112n) extend upward on the other side of the plate transverse to the side of the bus (122, 122a, ..., 122l, ..., 122m), and wherein one or more buses are interrupted at positions relative to the positions between successive heating bands.

7. The heating plate (1) according to any one of claims 1 to 5, characterized in that The resistive heating layer (112) is patterned into a plurality of mutually insulated resistive heating sections (A, B, C, D, E, F, ...), wherein one or more buses are interrupted at positions opposite to the positions of the boundaries between successive heating bands.

8. The heating plate (1) according to any one of claims 1 to 5, characterized in that The invention comprises a plurality of longitudinal bus parts insulated from each other, wherein the plurality of longitudinal bus parts comprises: Respective groups of first longitudinal bus portions (122bc, ..., 122dc, ...) are formed in a first plurality of first busses (122, 122b, 122d, ...) of a first polarity extending in a first lateral direction (x), Respective groups of second longitudinal bus portions (126bb, 126bd, ..., 126db, 126dd) are formed in a second plurality of buses (126, 126b, 126d, ...) of the first polarity extending in a second lateral direction (y) transverse to the first lateral direction, the second bus portions respectively extending at central positions between respective bus portions of consecutive buses of the first plurality of first buses; a respective group of third longitudinal bus portions (122cb, 122cc) formed in a third plurality of third buses (122a, 122c, ...) of a second polarity, wherein the respective third buses extend in the first lateral direction (x) between successive buses of the first plurality of first buses, and wherein the respective group of third longitudinal bus portions comprises respective pairs of third longitudinal bus portions of at least substantially the same length, the respective pairs of third longitudinal bus portions having respective first ends proximate to successive second longitudinal bus portions of successive second buses and having respective second ends facing each other, a respective group of fourth longitudinal bus portions (126cb, 126cc) formed in a fourth plurality of fourth buses (126a, 126c, ...) of said second polarity, wherein respective fourth buses extend in said second lateral direction between successive buses in said second plurality of second buses, and wherein respective groups of fourth longitudinal bus portions comprise respective pairs of fourth longitudinal bus portions of at least substantially the same length, said respective pairs of fourth longitudinal bus portions having respective first ends proximate to successive first longitudinal bus portions of successive first buses and having respective second ends facing towards each other, And wherein, the resistance heating layer includes corresponding resistance heating layer segments (112cbx, 112cby, 112ccx, 112dcy), and the corresponding resistance heating layer segments are located between the corresponding pair of first longitudinal bus portions and the adjacent third longitudinal bus portions, and between the corresponding pair of second longitudinal bus portions and the adjacent fourth longitudinal bus portions.

9. The heating plate (1) according to any one of claims 1 to 5, characterized in that It includes a plurality of mutually insulated longitudinal bus sections, wherein the plurality of longitudinal bus sections include: respective groups of first longitudinal bus portions formed in a first plurality of first busses (122, 122a, 122b, ...) of a first polarity extending in a first lateral direction (x), a respective group of second longitudinal bus portions formed in a second plurality of second bus portions (126, 126a, 126b, ...) of a first polarity extending in a second lateral direction (y) transverse to the first lateral direction (x), wherein each quad formed by a first bus pair of successive first bus portions and a second bus pair of successive second bus portions defines a respective area (Aaa) bounded by a respective pair of successive bus portions of each first bus of the first bus pair (122, 122a) and a respective pair of successive second bus portions of each second bus of the second bus pair (126, 126a); A corresponding cross bus (128aa) is arranged in each area, which divides each area into four quadrants (Aaa1, Aaa2, Aaa3, Aaa4), wherein each quadrant comprises a corresponding side portion of the resistive heating layer, the corresponding side portion of the resistive heating layer being electrically connected to a corresponding branch of the cross-shaped bus and a corresponding one of the bus portions (122_2, 126a_2, 122a_1, 126_1) of the busses (122, 126a, 122a, 126) defining the boundary of the area (Aaa); The first bus (122) of the pair of longitudinal bus sections (122_1, 122_2) of the first bus (122) has an end located between two adjacent bus sections of the first bus (126) of the second bus pair, the end defining the area, and the second bus (122_2) of the pair of longitudinal bus sections (122_1, 122_2) of the first bus (122) has an end located between a branch of the cross-shaped bus (128aa) facing the first bus (122) and a branch of the cross-shaped bus in a directly adjacent area facing the bus.

10. A heating device, characterized in that: Comprising a heating plate (1) according to any of the preceding claims and a support unit (2) for supporting the heating plate (1) at the second main side (12), wherein the support unit (2) comprises respective spring-loaded contact pins (21) for providing electrical contact with respective bus bars.

11. A method for making a heating plate, the method comprising the following steps: Providing (S1) a carrier plate (10) of a material having anisotropic etching behavior, the carrier plate (10) having a first main surface on its first main side (11) and having a second main surface on its second main side (12); etching (S6) a plurality of V-shaped grooves (121, 121a, 121b, ...) on the second main surface of the carrier plate (10), the V-shaped grooves tapering inwardly in the direction of the first main side (11) towards the first main surface; Depositing (S12) a resistance heating layer (112) on the first main surface; A corresponding bus bar (122, 122a, 122b, ...) is deposited (S11) in the V-shaped groove (121, 121a, 121b, ...) to provide a corresponding electrical connection (131) to the resistive heating layer (112) via a corresponding slit-shaped opening (13, 13a, 13b, ...) in the first main surface.

12. The method according to claim 11, characterized in that It also includes, before the etching (S6), measuring (S4) the thickness profile of the carrier plate (10), and providing (S5) an etching mask located on the second main surface, the etching mask having corresponding rectangular openings for the multiple V-shaped grooves (121, 121a, 121b, ...) to be formed, wherein the corresponding rectangular openings each have an appropriate width, which is proportional to the thickness of the carrier plate (10) of the corresponding V-shaped grooves (121, 121a, 121b, ...) to be formed.

13. The method according to claim 11, characterized in that Also includes: Providing (S6B) the corresponding slit-shaped openings (13, 13a, 13b, ...) on the first main surface is performed by anisotropically etching slit-shaped grooves (13, 13a, ...) in the first main surface of the carrier plate (10), and etching (S6A) a plurality of V-shaped grooves (121, 121a, 121b, ...) having a depth less than the thickness of the carrier plate (10), wherein the corresponding electrical connection (131) to the resistive heating layer (112) extends via the corresponding slit-shaped grooves to the corresponding bus lines (122, 122a, 122b, ...) in the V-shaped grooves (121, 121a, 121b, ...).

14. The method according to any one of claims 11 to 13, characterized in that A plurality of the bus bars (122) are deposited (S11) to form corresponding bus bar layers conforming to the surfaces of the corresponding V-shaped grooves (121).

15. The method according to any one of claims 11 to 14, characterized in that After the carrier plate (10) has been provided (S1) and before further steps are performed, and (S7) also after etching (S6, S6A) the plurality of V-grooves, an electrical insulator layer is (S2) provided on the surface of the carrier plate (10).

Images