Printing formulation transfer assembly
By adjusting the energy level of the energy source in the printing formulation transfer assembly, the problem of uneven interlayer heating in liquid electrophotographic printing systems was solved, improving print quality and substrate selection flexibility while reducing energy consumption.
Patent Information
- Application Number
- CN202511381762.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2017-04-10
- Publication Date
- 2025-11-07
AI Technical Summary
Existing liquid electrophotographic printing systems struggle to balance the heating requirements of different layers during image transfer, leading to overheating or underheating, which affects print quality and substrate selection.
By using an energy source in the printing formulation transfer assembly to provide energy to different layers at different predetermined intensity levels, the energy level can be adjusted according to the type of printing formulation, layer thickness, and number of layers received, thus avoiding overheating and underheating.
This allows for proper drying of each layer, improving print quality and substrate selection flexibility, while reducing energy consumption and equipment wear.
Smart Images
Figure CN120909084A_ABST
Abstract
Description
[0001] This application is a divisional application of the application for patent application number 201780088613.7, filed on April 10, 2017, entitled "Print Agent Transfer Assembly". BACKGROUND
[0002] Printing systems, such as liquid electrophotographic (LEP) printers, can use liquid toner and the like to form images on a photoconductive element. The images can be transferred to an intermediate element, where they are dried. The images can then be transferred to media. BRIEF DESCRIPTION OF DRAWINGS
[0003] For a more complete understanding, reference is now made to the following description taken in conjunction with the accompanying drawings in which: Figure 1 An example of a print agent transfer assembly is shown; Figure 2 An example of a print agent transfer assembly is shown; Figure 3 A flowchart showing an example of a method of transferring a print agent layer; Figure 4 A flowchart showing an example of a method of transferring a print agent layer; Figure 5 A flowchart showing an example of a method of transferring a print agent layer; and Figure 6 An example of a printing device is shown. DETAILED DESCRIPTION
[0004] Printing systems, such as liquid electrophotographic (LEP) printers, include a transfer element that receives an image from an image forming element. The image can be formed on the image forming element using liquid toner (hereinafter referred to as print agent). The image, also referred to as a print agent layer, is transferred to the transfer element, where it is at least partially dried using a heat source. The print agent layer can then be transferred to a substrate. The image formed on the substrate can include multiple layers of print agent that can be liquid when applied. In some examples, multiple layers can be transferred to the transfer element before being simultaneously applied to the substrate. In other examples, the layers can be transferred to the transfer element one at a time, and then to the substrate, such that there is one layer on the transfer element at a time.
[0005] Figure 1An example of a print agent transfer assembly 100 is shown that includes a print agent transfer element 102 to receive a first layer of print agent and a second layer of print agent. In some examples, the first layer of print agent and the second layer of print agent are received from an image forming element. The print agent transfer assembly 100 also includes an energy source 104 to provide energy to the first layer at a first predetermined intensity level and to the second layer at a different second predetermined intensity level. This provides drying assistance for the first and second layers. In some examples, the energy source 104 is used to provide energy after each layer is received, such that, for example, the energy source 104 is used to provide energy at the first predetermined intensity level after the first layer is received and at the second predetermined intensity level after the second layer is received. In some examples, there can be a controller, etc. to control the energy output by the energy source.
[0006] In some examples, the second layer is received on the first layer on the transfer element 102. In some examples, the first layer is transferred from the transfer element 102 to, for example, a substrate before the second layer is received on the transfer element 102.
[0007] The energy source 104 can, for example, provide energy to softened toner or resin particles within the print agent to cause such particles to coalesce into the layer to volatilize a portion of the liquid content of the print agent and / or to make the remaining print agent layer "tacky" so that it adheres to a substrate. By providing energy to different layers at different predetermined intensity levels, the print agent transfer assembly 100 can provide a specific level of energy that is appropriate for each layer. In some examples, the intensity level provided to a layer can be based at least in part on the type of print agent used for that layer. For example, print agent with darker pigments can absorb energy at a higher rate than print agent with lighter pigments, and thus the intensity level provided to a print agent layer can be lower for print agent with darker pigments than for print agent with lighter pigments. Figure 1 The method of can thus avoid a tradeoff between over-heating of darker layers and under-heating of lighter color layers. Over-heating and / or under-heating can in turn affect print agent adhesion to a substrate, print quality, and / or selection of available substrates, etc.
[0008] In some examples, the intensity level to be provided to a print agent layer can be determined based at least in part on a number of additional layers on the layer to be received on the transfer element. For example, where a transfer element receives a first layer and a second layer is received on the transfer element above the first layer, the energy level provided to the first layer can be lower than the energy level provided to the second layer. The first layer can absorb some energy and thus continue to dry while energy is applied to the second layer at a second intensity level. By accounting for the absorption of energy when applying subsequent layers, total energy consumption can be reduced and / or "over-drying" of early layers can be prevented or reduced. In some examples, a first intensity level provided by the energy source 104 to a first layer can be zero. Thus, for example, a first layer does not receive energy from the energy source 104 until a second layer is received by the transfer element on top of the first layer. The first layer can then absorb some energy while energy is applied to the second layer at a second intensity level. In some examples, the intensity level provided to a second layer can also be determined based on a number of additional layers to be received by the transfer element on the second layer. This can avoid a trade-off between under-heating of later layers (e.g., a final layer) and over-heating of earlier layers (e.g., a first layer) being made.
[0009] In some examples, the intensity level provided to a print agent layer can be determined based at least in part on a thickness of the print agent layer. For example, a higher intensity level can be selected for thicker layers as compared to thinner layers. This can thus avoid a trade-off between over-heating of thinner layers and under-heating of thicker layers being made.
[0010] Figure 2 An example of a print agent transfer assembly 200 is shown. The assembly 200 includes a print agent transfer element 202, which can be referred to in some examples as an intermediate transfer element (ITM). A first print agent layer and a second layer of print agent are received by the print agent transfer element 202 by being deposited on an outer surface 204 of the transfer element 202 from devices (not shown) that form each layer of print agent.
[0011] The print agent transfer assembly 200 includes a media drum 206 for receiving media while print agent layers are transferred from the transfer element 202 to the media. For example, the media can contact the print agent layers on the surface 204 and thereby transfer the layers to the media.
[0012] In some examples, a second layer of print agent is received on the first layer on the surface 204 before the first and second layers are simultaneously transferred to the media on the media drum 206. In some examples, the first layer is transferred from the surface 204 to the media before the second layer is received on the surface 204.
[0013] In some examples, the second layer of print agent can include the same print agent (such as, for example, the same color) as the first layer. In some examples, additional layers of print agent can be received on the print agent transfer assembly. In some examples, up to seven layers can be received. For example, third, fourth, fifth, sixth, and seventh layers can be received. In some examples, more than seven layers can be received.
[0014] The print agent transfer assembly 200 also includes an energy source 208 to provide energy to the layer of print agent on the surface 204. In some examples, the energy source 208 can include an energy source that can rapidly change its output level compared to the time between transfer of different layers to the transfer element 202. For example, the time between the start of transfer of a stack of layers can be on the order of hundreds of milliseconds (e.g., 100-300 ms, and in some examples, approximately 215 ms), and the time between the end of transfer of a single layer to the transfer element 202 and the start of transfer of the next layer to the transfer element can be on the order of tens of milliseconds (e.g., 10-50 ms, in some examples, approximately 35 ms). In some examples, the energy source 208 can be selected based on the time between the end of transfer of one layer to the transfer element 202 and the start of transfer of the next layer to the transfer element that the energy source 208 can increase or decrease its output. For example, the energy source 208 can be capable of increasing or decreasing its output energy in less than 35 ms.
[0015] In this example, the energy source 208 includes an array 210 of vertical cavity surface emitting lasers (VCSELs) that extend over the width of the layer of print agent on the surface 204 and are controlled to provide energy to the layer on the surface at a predetermined level of intensity. In some examples, the array 210 of VCSELs can be capable of switching from one level of energy output intensity to another in approximately, or less than, one millisecond. Thus, each layer of print agent on the surface 204 can receive a respective predetermined level of energy intensity from the array 210 of VCSELs. In some examples, the energy source can include alternative technologies, such as an array of light emitting diodes (LEDs) to provide energy to the layer of print agent. LEDs can also be associated with rapid output control, such as switching from one level of energy output intensity to another in approximately, or less than, one millisecond.
[0016] In some examples, other sources of heating can also be present, such as, for example, internal heating of the transfer element 202. In some examples, the heat supplied by the transfer element 202 can be taken into account in determining the energy to be provided to the layer.
[0017] The energy source 208 also includes an air source 212 and an air exhaust 214 for directing an air flow over the print agent layer on the surface 204. The air source 212 can be controlled to provide some additional control over the heating of the layer, and / or can take the air flow rate into account when determining the amount of energy to be provided to the layer.
[0018] By providing energy to different layers at different predetermined intensity levels, the print agent transfer assembly 200 can provide a certain level of energy that is appropriate for each layer. As noted above, the intensity level provided to a layer can be based on the type of print agent used for the layer, the number of additional layers to be received on the surface 204 over the layer, and / or the thickness of the print agent layer.
[0019] Figure 3 An example of a method 300, which can be a method of transferring a print agent layer, is shown. The method 300 includes determining a level of heat flow to be supplied to a print agent layer on a layer-by-layer basis in block 302. In some examples, the level of heat flow for a print agent layer can be determined based on at least one of a type of print agent in the print agent layer, a number of additional layers to be received on the print agent layer on a transfer element, and a thickness of the print agent layer.
[0020] The method also includes receiving the print agent layer on a transfer element in block 304. The method includes supplying the determined level of heat flow to the print agent layer on the transfer element in block 306.
[0021] Figure 4 An example of a method 400, which can be a method of transferring a print agent layer, is shown, and which can follow the method of Figure 3 The method 400 includes transferring a print agent layer to a media in block 402, and receiving an additional print agent layer on a transfer element in block 404. Thus, for example, each layer of print agent can be individually received on a transfer element, disposed with heat flow, and transferred to a media. The method 400 can additionally include determining an additional level of heat flow to be supplied to the additional print agent layer in block 406, and supplying the determined additional level of heat flow to the additional print agent layer on the transfer element in block 408.
[0022] Figure 5 An example of a method 500, which can be a method of transferring a print agent layer, is shown, and which can follow the method of Figure 3The method 500 includes receiving, in block 502, an additional print agent layer on top of a print agent layer on a transfer element, and determining, in block 504, an additional level of heat flux to be supplied to the additional print agent layer. The method 500 also includes supplying, in block 506, the determined additional level of heat flux to the additional print agent layer on the transfer element, and simultaneously transferring, in block 508, the layer and the additional layer to a medium. Thus, for example, multiple layers are assembled on a transfer element before being simultaneously transferred to a medium.
[0023] Figure 6 An example of a printing device 600 is shown. The printing device 600 includes a first roller 602 to form a print agent layer. A second roller 604 receives the print agent layer from the first roller 602. A heater 606 heats the print agent layer on the second roller. A controller 608 controls the heater to a predetermined output level based on at least one layer characteristic. In some examples, the layer characteristic can be a position of the layer in a stack of layers that are deposited on the transfer roller 604 before being transferred to a web. In some examples, the layer characteristic can be a thermal absorption property of the layer, such as one of a layer thickness, a layer brightness, and a layer color.
[0024] The disclosure is described with reference to flowcharts and / or block diagrams that illustrate the methods, apparatus, and systems according to examples of the present disclosure. Although the flowcharts describe a particular order of execution, the order of execution can differ from that which is depicted. Blocks described with respect to one flowchart can be combined with blocks of another flowchart. It will be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by machine readable instructions. The machine readable instructions can be implemented in a processor of a general purpose computer, a special purpose computer, an embedded processor, or a processor of other programmable data processing apparatus to produce a machine so that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions of the flowcharts and / or block diagrams.
[0025] The machine readable instructions may, for example, be executed by a general purpose computer, a special purpose computer, an embedded processor, or a processor of other programmable data processing apparatus to implement processes described in the specification and diagrams. Specifically, a processor or processing apparatus can execute machine readable instructions. The functionality of the various modules of the apparatus and the devices can thus be carried out by a processor executing machine readable instructions stored in a memory, or a processor operating in accordance with instructions embedded in a logic circuit. The term "processor" is to be interpreted broadly to include a CPU, processing unit, ASIC, logic unit, or programmable gate array, etc. The processes and functionality of the modules can all be performed in a single processor or divided amongst several processors.
[0026] Such machine readable instructions can also be stored in a computer readable storage that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions which run via the processor of the computer or network programmable apparatus implement the processes of the flowcharts and / or block diagrams.
[0027] Such machine readable instructions can also be loaded onto a computer or other programmable data processing devices, so that the computer or other programmable data processing devices performs a series of operations to produce computer-implemented processing, thus the instructions executed on the computer or other programmable devices realize the functions specified by the flow(s) in the flow charts and / or the block(s) in the block diagrams.
[0028] Further, the teachings herein can be implemented in the form of a computer software product, the computer software product being stored in a storage medium and comprising a plurality of instructions for making a computer device implement the method described in the examples of the present disclosure.
[0029] Although aspects of methods, devices, and related operations have been described with reference to certain examples, various modifications, changes, omissions, and substitutions can be made without departing from the spirit of the disclosure. It is therefore intended that the methods, devices, and related operations be limited only by the scope of the appended claims and their equivalents. It should be noted that the foregoing examples illustrate rather than limit the content described herein, and those skilled in the art will be able to design many alternative implementations without departing from the scope of the appended claims. Features described with respect to one example can be combined with features of another example.
[0030] The word "comprising" does not exclude the presence of elements other than those listed in a claim, "a" or "an" does not exclude the presence of plural referents, and a single processor or other processing resource can fulfill the functions of several units recited in the claims.
[0031] The features of any dependent claim can be combined with features of any independent claim or of any other dependent claim.
Claims
1. A print agent transfer assembly comprising: a print agent transfer element to receive a first layer of print agent and a second layer of print agent, wherein the print agent transfer element is to transfer the first layer of print agent to a substrate prior to receiving the second layer of print agent; and an energy source to provide energy to the first layer at a first predetermined intensity level and to the second layer at a second different predetermined intensity level, wherein the first predetermined intensity level is predetermined based on a type of the print agent in the first layer of print agent, wherein the type of print agent comprises a color, and wherein an intensity level provided to a print agent having a darker pigment is lower than an intensity level provided to a print agent having a lighter pigment.
2. The print agent transfer assembly of claim 1, wherein, the energy source comprises at least one of a plurality of light emitting diodes (LEDs) and a plurality of vertical cavity surface emitting lasers (VCSELs).
3. The print agent transfer assembly of claim 1, wherein, the first predetermined intensity level is lower than the second predetermined intensity level.
4. The print agent transfer assembly of claim 1, wherein, the first predetermined intensity level is zero.
5. A method comprising: determining a level of heat flow to be supplied to a layer of print agent on a layer-by-layer basis; receiving the layer of print agent on a transfer element; and supplying the determined level of heat flow to the layer of print agent on the transfer element, transferring the layer of print agent to a medium; and after transferring the layer, receiving a further layer of print agent on the transfer element, wherein the level of heat flow is determined based on a type of print agent in the layer of print agent, wherein the type of print agent comprises a color, and wherein an intensity level provided to a print agent having a darker pigment is lower than an intensity level provided to a print agent having a lighter pigment.
6. The method of claim 5, comprising: determining a further level of heat flow to be supplied to the further layer of print agent; and supplying the determined further level of heat flow to the further layer of print agent on the transfer element.
7. The method of claim 6, wherein, the level of heat flow is lower than the further level of heat flow.
8. The method of claim 6, wherein, the level of heat flow is zero and the further level of heat flow is non-zero.
9. A printing device comprising the print agent transfer assembly of any of claims 1-4.