System and methods for developing a relief precursor to obtain a relief structure

Abstract

The present disclosure relates to a system for (thermally) developing a relief precursor. The system has a development means for developing the relief precursor so as to obtain a developed relief structure, such as a printing plat. The system has an exhaust for receiving an airflow with volatile components generated during heating development of the relief precursor. The system has further has a liquid collection means configured to condensate evaporated volatile components to obtain a liquid. The liquid is preferably collected using centrifugal force.

Description

[0001]

[0002] The present invention relates to the technical field of a system for developing a relief precursor, such as a system for thermal or solvent development. The relief precursor may be developed into a relief structure, such as a printing plate or sleeve and / or a relief structure for use in relief printing such as flexographic or letterpress relief printing. The invention further relates to a methods of thermally or solvent developing the relief precursor.

[0003] BACKGROUND

[0004] In conventional processes of thermally developing printing plates, precursors are heated and volatile components may escape and evaporate into the air within the thermal developing apparatus. In conventional processes of solvent developing printing plates, some components may escape the solvent which may cause contamination within the solvent developing apparatus.

[0005] The volatile components may contaminate the apparatus and the environment. Therefore, there is a need to separate and collect the volatile components in an appropriate manner. Approaches have been taken to address the issue of contamination. However existing approaches typically have the drawback that they are complex and / or require high energy input.

[0006] Therefore, there is a need to have the volatile components separated and collected in a safe and energy-efficient manner.

[0007] US2005 / 084791 discloses a method and an apparatus for thermally developing a photosensitive element, and particularly a method and apparatus for controlling vapor and condensate created during thermal treating of the photosensitive element.

[0008] SUMMARY OF THE INVENTION

[0009] The object of embodiments of the present invention is to limit contamination within a system for developing relief precursors. A further object of embodiments of the present invention is to fill in the need to have the volatile components separated and collected in a safe and energy-efficient manner during development of the relief precursor. According to an aspect, there is provided a system for developing a relief precursor, said system comprising a development means, at least one exhaust, a liquid collection means. The development means is configured for developing the relief precursor and so as to obtain a developed relief structure. The development means can by a thermal development means or a solvent development means. The at least one exhaust is configured for receiving an airflow with evaporated volatile components generated during development of the relief precursor. The liquid collection means is connected to the at least one exhaust and configured to condensate evaporated volatile components to obtain a liquid.

[0010] Embodiments of the invention are based on the insight that by having the exhaust configured for receiving the evaporated volatile components, the volatile components may be captured from a location where the volatile components evaporate and delivered to the liquid collection means. In this manner, amounts of volatile components can be captured which is beneficial for safety and environmental reasons. Furthermore, by having the liquid collection means connected to at least one exhaust and configured to condensate evaporated volatile components to obtain a liquid, the evaporated volatile components can be collected in a safe manner without requiring high amounts of energy.

[0011] The system as described herein is beneficial over an approach of heating and using a catalyst to oxidize components to form air with carbon dioxide and water vapor. Namely, such catalyst may be expensive and may need to be replaced causing operation downtime. More so, the heating in the catalyst approach requires additional high energy input. The system as described herein may further have a higher efficiency over an approach of using a static adsorbent material alone (e.g. activated carbon, charcoal, alumina, zeolites) to capture the volatile components.

[0012] It is preferred that the liquid collection means is configured to collect the liquid with evaporated volatile components using centrifugal force. Such a force can be easily provided and results in the liquid with the components to be easily collected. By having the liquid collected, the volatile components can be easily disposed, for example via an outlet.

[0013] The relief precursor, e.g. a printing plate relief precursor, can be developed into the developed relief structure, e.g. a developed printing plate, by any suitable development means, including a thermal development means and solvent development means. When thermally developing the precursor, the development means is a thermal development means configured for heating the relief precursor and for removing liquified portions of the heated relief precursor to obtain the developed relief structure, wherein the evaporated volatile components are generated during heating of the relief precursor. Thermally developing relief precursors is described in EP3629089A1 and is incorporated herein by reference.

[0014] When solvent developing the precursor, the development means is a solvent development means comprising: a solvent washing means configured to remove portions of the relief precursor with aid of a solvent (also called a developing liquid or a washing liquid). Solvent developing is described in EP4009106A1. A suitable apparatus for solvent developing, also called a washer apparatus is described in WO2021198012.

[0015] Preferably, the liquid collection means is provided with an outlet configured to allow removal of the collected liquid from the collection means. This way, an operator may easily dispose the liquid with the captured components. The outlet may as such be designed to channel liquid to for example a container, preferably a removable container. In this manner, the liquid can be stored in the container.

[0016] Preferably, the liquid collection means comprises a rotor with one or more impact surfaces to impact the airflow with the evaporated volatile components such that droplets with the volatile components are formed on the impact surface, and wherein the collection means are preferably configured to shed off the droplets from the impact surfaces using centrifugal force. This way, the droplets holding the volatile components can be easily separated from the airflow and collected in a safe manner. By having the components separated from the air within the airflow, the airflow is (at least partially) purified.

[0017] Preferably, the housing is configured to guide the obtained liquid to the outlet to allow removal of the liquid from the collection means. More preferably, a peripheral channel is defined between the housing and the rotor, said channel being configured to guide liquid to the outlet. Preferably, a catch rib is provided near the outlet configured to catch and guide liquid to said outlet.

[0018] Preferably, the rotor is arranged within a housing having the outlet, wherein the peripheral channel is defined between the housing and the rotor, said peripheral channel being configured to guide liquid to the outlet. This way, droplets that are shed off, e.g. from the impact surfaces, can be collected via the outlet. The one or more impact surfaces of the rotor preferably extend in a radial direction, preferably towards a central rotational axis ca of the rotor. Preferably, the liquid collection means has a housing, such as a cylindrical outer casing, herein the rotor, such as cylindrical drum, is rotationally arranged within the housing, wherein the rotor is configured to rotate around its central axis such that liquid on the rotor is forced outwardly, from and / or through the rotor, against the housing by a centrifugal force. By having the outward movement of the liquid on the rotor, the volatile components can be separated and collected in a safe manner without complex steps or a high energy input. Preferably, the housing is configured to guide the obtained liquid to an outlet to allow removal of the liquid from the collection means. More preferably, the housing is provided with a catch rib arranged within the housing to catch and guide liquid to the outlet. By having the catch rib, higher volumes of liquids may be collected and may subsequently be extracted from the liquid collection means.

[0019] The rotor may be formed as a cylindrical drum having openings for allowing liquid to pass through upon rotation of the rotor; wherein the openings are for example formed as a pattern of holes distributed across the cylindrical drum. By having the holes in the drum, the droplets with evaporated volatile components can be separated and collected in a safe manner.

[0020] The rotor may be provided with one or more vanes functioning as impact surface for impacting the evaporated volatile components and the one or more vanes may be typically arranged such that they generate a flow for attracting the airflow with evaporated volatile components upon rotation of the rotor. This way, contaminated air with evaporated volatile components or air with droplets of volatile components can be sucked from the location of evaporation and transported to the liquid collection means via the at least one exhaust, facilitating ease of separation and collection in a safe manner.

[0021] The one or more vanes preferably each have a surface area as measured from the side impacting the airflow, wherein said surface area is at least 150 cm2, preferably at least 200 cm2, more preferably at least 275 cm2. This way, efficiency of volatile component collection may be increased. The surface area is understood as the surface area of one side of an individual van of the one or more vanes, more in particular the area which is being impacted upon rotation of the vane.

[0022] Preferably, the rotor is configured to rotate at speeds of more than 800 rpm, preferably more than 1000 rpm, preferably more than 1500 rpm, more preferably speeds between 800 rpm - 4000 rpm, such as between 2500 - 4000 rpm. Surprisingly, it was found that these rotational speeds may achieve a good capturing rate such that the volatile components can be collected in a safe manner. Notably, the speed can be manually or automatically controlled by a control means configured, such as a controller. The control means may be configured to control the rotational speed of the rotor of the liquid collection means. The control means may be configured to rotate the rotor at constant or alternating speeds.

[0023] The rotor preferably has an inner wall made from and / or covered with a porous material. This way, an increased separation efficiency may be achieved. Examples of porous material are an open cell foam, a porous film, a porous metal, a metal wool, a woven or a non-woven material. Combinations thereof are also possible.

[0024] The system may further be provided with a silencer arranged for silencing noise from the liquid collection means, such as noise from the rotor. The silencer preferably comprising a foam, such as a polyether foam since this dampens noise. Such dampening benefits comfort of nearby operators.

[0025] The liquid collection means may be arranged at a position higher than the thermal development means, preferably at least 0.5 meter higher, more preferably at least 1 meter higher. Such arrangement allows easy access to the developed relief such as a developed printing plate. The arrangement may further benefit comfort of nearby operators since the noise of the collection means (which can have a rotating rotor) is further removed from the nearby operators when operating the system.

[0026] The system may further be provided with a container, preferably a removable container, for storing collected liquid comprising the volatile components.

[0027] Preferably, the system is further provided with a gas liquid separator arranged downstream of the liquid collection means and connected so as to receive a stream exiting the liquid collection means, e.g. exiting from the outlet as described above. The separator is configured the separate a liquid from a gas. The gas may be returned to the liquid collection means via a feedback arrangement. The separated liquid may be stored in the container. Preferably, the separator is configured to feed the gas stream back to the liquid collection means and upstream of or to the silencer.

[0028] It is preferred that the system has one or more ducts connecting the at least one exhaust to the liquid collection means. The duct(s) may be provided with one or more drains for draining liquids from the ducts for ease of maintenance and / or cleaning. The drain(s) is / are typically arranged at a position within the ducts such that liquids within the ducts are guided to the drains via gravitational force. In this manner, ease of maintenance is provided.

[0029] The system is preferably configured to have the airflow with the evaporated volatile components flowing from the exhaust to the liquid collection means through the one or more ducts at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3I hr, most preferably 600 - 800 m3 / hr. The flow speeds may be controlled with a controller or control system. The flow may be generated by rotation of the one or more vanes of the rotor and / or by one or more fans to help in generating the airflow.

[0030] The at least one exhaust for receiving the airflow with evaporated volatile components may comprise a first exhaust, a second exhaust and optionally a third exhaust. The first exhaust is arranged at a first position, the second exhaust is arranged at a second position, and the optional third optional third exhaust is arranged at a third position. The first and second position are chosen such that an airflow with evaporated volatile components is received from different locations. This way, more volume of contaminated air within the system can be captured and purified and / or extracted from the system. Having several exhausts facilitates collection of volatile components, such as volatile organic components VOC’s, or components of the washing liquid that evaporate during solvent developing or compounds evaporated while heating the relief precursor during thermal development.

[0031] The system may further have one or more restrictor plates arranged in one or more ducts connecting a respective exhaust to the liquid collection means. Preferably at least two restrictor plates are arranged within at least two ducts so as to regulate a relative flow speed within the at least two ducts. By having the restrictor plate within the ducts, gathering of evaporated volatile components may be improved by focusing a suction force to places of higher demand.

[0032] The development means can be any means suitable for transforming the relief precursor (typically pre-exposed with UV so as to have cured and non-cured portions) into a relief structure, preferably the development means is a thermal development means.

[0033] The relief precursor typically comprises a photosensitive layer (also called a curable layer). The material within said layer may be cured with UV light. The relief precursor may further comprise a dimensionally stable support layer for supporting the photosensitive layer. Further layers may be present in between. The photosensitive layer can be subjected to a pretreating so as to create cured and uncured portions, for example by exposing the photosensitive composition of the photosensitive layer. Depending on the technique and type of material of the photosensitive layer, one of cured or uncured portions may be liquified (typically by heating) and subsequently removed by any suitable removal means. An example of exposing is described in EP4009106A1.

[0034] The thermal development means may comprise a heater (such as an IR lamp), a developer (such as liquified portion removal system comprising a heated roll and a web for contacting the relief precursor) and a support (such as a supporting drum). The heater is configured for heating and liquefying parts of the relief precursor, said heater preferably being chosen from: an IR lamp, a means for delivering a hot gas or liquid stream, a hot surface, or a combination thereof. The developer arranged for removing the liquified parts or portions from the relief precursor. The support is arranged for supporting the relief precursor. Preferably, the support is chosen from: a rotating drum, an endless belt, a flat or curved bed, an oscillating belt, or a combination thereof. Preferably, the developer comprises a heating roll which has a radius of curvature in the range from 20 to 360 mm, in particular at a location where the support contacts the developer. Such curvature has been found to result in relief structures with desired properties.

[0035] The support and / or the developer may be provided with a compressible layer, preferably with a compression modulus between 10 and 20 000 kPa at least at the location where the support and the developer contact each other, optionally with the relief precursor in between. The support and the developer may thus make direct or indirect contact with each other. Designing the support and / or the developer, preferably the support, with the compression modulus as stated, relief structures could be obtained with improved printing properties. The compression modulus can be measured according to EN ISO 604:2003.

[0036] The developer of the thermal development means preferably comprises one or more of:

[0037] - a rotating drum, an endless belt, a (oscillating) flat or curved bed, a (oscillating) belt, a brush, a rotating brush or any combination thereof, the rotating drum is preferably a heating roll which has a radius of curvature in the range from 20 to 360 mm as this achieves a desired removal of the liquified portions.

[0038] - a material capable of removing, absorbing or adsorbing liquefied material of the relief precursor, said material preferably comprising a film of a woven or nonwoven material, a natural or an artificial polymer, a paper, a metal, a composite or combinations thereof.

[0039] - a surface for coming into contact with the relief precursor, said surface being provided with a metal, an alloy, a glass, a ceramic, a polymer, a composite or combinations thereof.

[0040] In addition to the liquid collection means, the system may further be provided with a separation means, preferably chosen from a paper filter, electrostatic filter, metal mesh filter, metal wool filter. The separation means is preferably arranged downstream of the liquid collection means and connected so as to receive the air flow flowing out of the liquid collection means. In this manner, further separation and optional collection of the volatile components can be facilitated without the need for relying on complex and high energy approaches. A further aspect relates to the use of a moving impact surface, such as a surface of a vane, for collecting volatile substances arising from a relief precursor during the thermally developing thereof, said moving preferably comprises a rotation of the impact surface. The rotation has been found to facilitate capture and collection of volatile substances (also referred to as volatile components). More preferably, the vane is a blade attached to a rotating axis extending substantially parallel to an airflow with the volatile substances. This way, the blade impacts the volatile substances from a sideways direction relative to the airflow. The volatile substances can be captured on the surface of the blade. The relief precursor typically has a photosensitive layer with curable or crosslinkable material which can be cured upon exposure to UV light. After exposure, cured and non-cured portions are created in the photosensitive layer such that one of the portions can be liquified and removed leaving behind a relief within the photosensitive layer. The use has the benefit that the relief precursor can be developed in a safer manner.

[0041] A further aspect relates to a method of thermally developing a relief precursor.

[0042] The method comprising the steps of:

[0043] - providing a relief precursor;

[0044] - heating the relief precursor and removing liquified portions of the heated relief precursor, so as to obtain a developed relief structure, such as a printing plate;

[0045] - collecting evaporated volatile components from an airflow by impacting said airflow with evaporated volatile components against an impact surface such that a liquid is formed on said impact surface and subsequently collecting said liquid. The liquid with the components is preferably collected using a centrifugal force. The impact surface is preferably a vane of a rotor. The effects and benefits explained in connection to above system apply mutatis mutandis to embodiments of the method. By having the evaporated volatile components collected via impacting the airflow with the volatile components, the relief precursor can be developed in a safer manner. More so, by having the volatile components collected, comfort of nearby operators may be increased. The nearby operators may as such be protected from arising unpleasant and / or strong smells. The relief precursor may comprise a photosensitive layer supported by a mechanically stable support layer.

[0046] Another aspect relates to a method of solvent developing a relief precursor. The method of solvent developing comprising the steps of:

[0047] - providing a relief precursor; typically having exposed and non-exposed portions;

[0048] - developing the relief precursor by removing portions, such as the non-exposed portions, of the relief precursor with a solvent (also called a developing liquid or washing liquid), so as to obtain a developed relief structure, such as a printing plate; - collecting evaporated volatile components from an airflow by impacting said airflow with evaporated volatile components against an impact surface such that a liquid is formed on said impact surface and subsequently collecting said liquid.

[0049] The relief precursor may be subjected to a pre-exposure step with UV light to create exposed and non-exposed portions, so that one of the two portions can be washed away during development such that the relief structure is obtained.

[0050] The method preferably has the step of rotating the rotor at speeds of more than 800 rpm, preferably more than 1000 rpm, more preferably more than 1500 rpm, even more preferably speeds between 800 rpm - 4000 rpm, such as between 2500 - 4000 rpm. High efficiency and capture or collection of the volatile components could thereby be achieved.

[0051] The method preferably has the step of transporting the air with evaporated volatile components from an exhaust to a liquid collection means (which may have one or more features as explained above). The exhaust configured for receiving an airflow with evaporated volatile components generated during heating of the relief precursor. The liquid collection means is configured to condensate evaporated volatile components to obtain a liquid. The air may be transported at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr, most preferably 600 - 800 m3 / hr. The airflow be provided via any flow generation means, such as a blower or a fan and / or via the one or more vanes of the rotor of the liquid collection means. The method may further comprise controlling the flow speed with a control means.

[0052] Collecting the liquid preferably comprises collecting the liquid in a container. The container may be removable. In this manner, easy disposal is proved.

[0053] BRIEF DESCRIPTION OF DRAWINGS

[0054] The accompanying drawings are used to illustrate presently preferred non limiting exemplary embodiments of the present invention. The above and other advantages of the features and objects of the invention will become more apparent, and the invention will be better understood from the following detailed description when read in conjunction with the accompanying drawings, in which:

[0055] Figure 1 is a schematic view a system according to an exemplary embodiment.

[0056] Figure 2 is a schematic view a system according to an exemplary embodiment. Figure 3 is a more detailed schematic view of a system with thermal development means according to an exemplary embodiment.

[0057] Figure 4 is a schematic perspective of an exemplary embodiment of a thermal development means. Figure 5 is a schematic perspective of an exemplary embodiment of a liquid collection means.

[0058] Figure 6 is a schematic perspective view of a washing apparatus according to an exemplary embodiment, said apparatus being provided with a liquid collection means.

[0059] Figure 7 is a schematic perspective of an exemplary embodiment showing a gas liquid separator.

[0060] It is to be readily understood that same or similar elements referred to with the same reference numbers may have the same features and effects.

[0061] DETAILED DESCRIPTION

[0062] The relief precursor as described herein can be any suitable precursor to form a developed relief therewith, preferably via thermal development. The obtained developed relief or relief structure can be used for flexographic printing and letterpress printing.

[0063] The relief precursors typically comprise a photosensitive layer having components that cure or change behavior when exposed to electromagnetic radiation. The precursor may be exposed to the electromagnetic radiation in (predetermined) selected areas such that cured and uncured portions are created in the photosensitive layer. After the exposure, the photosensitive layer may be developed whereby one of the exposed or not exposed portions are removed leaving behind a pattern of reliefs. The exposure of the precursor can be done in several ways.

[0064] A first way is exposure performed through a mask. This photographic mask has transparent regions which determine the areas of the precursor to be cured. The electromagnetic radiation passes the transparent regions and cures the photosensitive layer underneath. A second way uses a mask that is produced in situ directly on the relief precursor by, for example, using a laser ablatable mask layer wherein a motif is created with a laser light source. Other methods such as thermographic writing can be used to create a masking pattern. More details on exposing the relief precursor are given in EP4009106A1, in particular paragraph 83 and the passages in connection to figure 1 and figure 2A, 2B which is incorporated herein by reference. After the exposure, the precursor can be developed. The development of the precursor can be done is several ways, such as a solvent and thermal development. In thermal development, the precursor is subjected to heat to liquify parts of the precursor such that they can be removed and leave behind parts which form a relief. Figure 1 schematically represents a system 1 for thermally developing a relief precursor RP. After development, a developed relief DR is obtained. The developed relief DR can be any relief structure, such as a printing plate or sleeve and / or a relief structure for use in relief printing.

[0065] The relief precursor can have a photosensitive layer PL supported by a mechanically stable support layer SL. Other layers may be present, examples are an oxygen barrier layer, a laser-ablatable mask layer, an adhesion layer, a UV / VIS light and / or IR light absorbing layer, a monomer diffusion control layer, a surface control layer, a protection or cover foil or a combination thereof.

[0066] The obtained relief structure, i.e. developed relief DR, can be used as a flexographic printing plate, a letter press plate, a relief printing plate, a (flexible) printed circuit board, an electronic element, a microfluidic element, a micro reactor, a phoretic cell, a photonic crystal, an optical element or a Fresnel lens.

[0067] An example of a photosensitive composition for use within the photosensitive layer of the precursor is at least one ethylenically unsaturated compound, at least one photoinitiator or photoinitiator system, a binder. More details of the photosensitive composition are given in EP4009106A1 which is incorporated herein by reference.

[0068] Figure 1 further shows a development means 10. The development means 10 can be a means to develop the relief precursor by aid of a solvent (also called developing liquid) or a means such as a thermal development means for heating the relief precursor. Upon heating, liquified portions may be formed which are to be removed such that a developed relief DR is obtained.

[0069] The development means 10 can be configured in any suitable manner to remove liquified portions of the heated relief precursor. The system 1 is provided with an exhaust 40 for receiving an airflow with volatile components generated during heating of the relief precursor. The volatile components may escape from the relief precursor via partial or full evaporation. The airflow is represented with AFC. The volatile components can be present in said flow of air in any phase possible such as vapor, or may be present in the form of small droplets such that a mist like airflow is present. The exhaust 40 is connected to the liquid collection means 20.

[0070] The exhaust 40 may also be referred to as an exhaust manifold for collecting the evaporated volatile components, or more in particular the air with the volatile components. The exhaust 40 may function as an inlet or inlet manifold to the means forming the connection with the liquid collection means, such as one or more ducts. More so, the liquid collection means 20 may be connected to the at least one exhaust 40 via any suitable means for forming said connection, preferably one or more ducts 50. The liquid collection means 20 is configured to condensate evaporated volatile components to obtain a liquid. More preferably, such that the liquid with evaporated volatile components can be collected by use of a centrifugal force.

[0071] Figure 1 further shows a duct 50 connecting exhaust 40 to the liquid collection means 20. It is noted that several ducts may be present which connect several manifolds to the liquid collection means 20 (as will be explained further in connection with figure 3). The manifolds are preferably positioned near locations where volatile components may escape from the relief precursor. For example near or within proximity of the heating sources arranged within the system for heating the relief precursor. The one or more ducts 50 may be provided with one or more drains for draining liquids from the one or more ducts.

[0072] The airflow with the evaporated volatile components AFC may be transported from the exhaust 40 to the liquid collection means 20 through ducts 50 at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr, most preferably 600 - 800 m3 / hr. The flow speed may be provided via any suitable means for generating a flow, such as a blower or a fan such that the evaporated volatile components AFC are transported to the liquid collection means 50. The means for delivering a flow may be arranged at any suitable position with respect to the exhaust or collection means 50.

[0073] For example, a fan (not shown) generating a suction force can be arranged downstream of the liquid collection means 20 such that the airflow AFC is sucked towards the liquid collection means. More preferably, the liquid collection means 20 itself may be configured to create or generate a suction force. The liquid collection means may have a rotor with one or more vanes rotatably arranged around a rotational axis and being configured to create the suction force upon rotation thereof. The vanes (not shown) may function as impact surfaces to impact the airflow with the evaporated volatile components AFC such that droplets with the volatile components are formed on the impact surface. The droplets may then be shed off from the impact surfaces using centrifugal force. The liquid collection means is preferably further configured for collecting the liquid in a container or for collecting the liquid via an outlet.

[0074] Notably, a separation means (not shown) may be provided to the system in addition to the liquid collection mean. The separation means is preferably chosen from a paper filter, electrostatic filter, metal mesh filter, metal wool filter. The separation means is preferably arranged downstream of the liquid collection means and connected so as to receive the air flow AF flowing out of the liquid collection means.

[0075] Figure 2 is a schematic view a system according to another exemplary embodiment. The same or similar features are referred to with the same reference numerals. System 1 can be embodied as an apparatus having a housing which houses development means 10. Development means 10 may be a solvent or thermal development means, preferably a thermal development means. The liquid collection means 20 may be placed outside the housing as illustrated in figure 1 or within the housing as illustrated in figure 2.

[0076] Figure 3 is a schematic view a system according to another exemplary embodiment. The figure shows system 1 with a development means 10, preferably thermal development means, and liquid collection means 20. The figure further shows exhausts 40, 41, 42 which are connected to the liquid collection means 20 via a connection means 50, here in the form of ducts 50.

[0077] Exhausts 40, 41, 42 are arranged for receiving the airflow with evaporated volatile components AFC. More in particular, the exhausts 40, 41, 42. The volatile components may escape from the relief precursor upon the heating thereof, for example heating via one or more heating sources such as heater 11. Heater 11 is preferably an IR lamp so that the relief precursor RF is pre heated before being contacted with the heated roll 12a. The development means 10 is arranged within a housing while liquid collection means 20 is arranged outside said housing (as explained in connection figure 1 above). As an alternative, the liquid collection means 20 may be arranged within the housing (as explained in connection figure 2 above).

[0078] Figure 3 further shows an example of support 13 and developer 12 arranged for removing the liquified parts from the relief precursor. One or both of support 13 and developer 12 can be configured to supply additional heat if needed. Support 13 may also be cooled by a passive or active cooling system. The developer 12 as shown is illustrated as a system with heated roll 12a which is arranged to contact the relief precursor RF such that a web 12b is pressed thereon which takes away liquified portions of the relief precursor. The web 12b may be made of a material capable of removing, absorbing or adsorbing liquefied material of the relief precursor. Other techniques may use in addition to or as an alternative to remove the liquified portions of the relief precursor.

[0079] The liquid collection means 20 of figure 3 may have any one or more of the features as explained herein, in particular as explained in connection with the other figures. Figure 3 illustrates the liquid collection means 20 arranged at a position higher than the thermal development means 10, preferably at least 0.5 meter higher, more preferably at least 1 meter higher. Liquid collection means 20 may also be arranged such when the system is installed or operated, the liquid collection means 20 is arranged at a height h above ground level GL, said height h being at least 1.2 meter, more preferably at least 1.4 meter, even more preferably at least 1.5 meter. This way, comfort of nearby operators is considered and their subjection to (unpleasant) noise may be reduced. Such arrangement further provides easy access to reach out to the developed relief.

[0080] Figure 3 further shows that system 1 is provided with container 25 to collect the obtained liquid with the components via outlet 24 from collection means 20. The container may be removably arranged for easy disposal. The liquid collection means 20 preferably has a catch rib 23 (not shown in figure 3, further shown in figure 5) to catch and guide liquid to the outlet 24.

[0081] Figure 3 further shows that ducts 50 connecting the exhausts 40, 41, 42 to the liquid collection means 20. Notably, one or more exhausts can be present. The exhausts may function as inlet manifolds for sucking in air with evaporated components which have escaped the relief precursor RP. Namely, the components may escape from the relief precursor and should be captured and collected so as to avoid contamination within the system 1. Duct 50 connecting the exhausts 40, 41 , 42 to the liquid collection means 20 is provided with drains 51 for draining liquids from the duct. Drain 51 is arranged at a relative low position in comparison with one or more of development means 10 and liquid collection means 20. This way liquid within the ducts 50 is guided to drain 51 via gravitational force. This way, ease of maintenance is provided.

[0082] The ducts 50 are preferably configured so as to allow airflow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr, most preferably 600 - 800 m3 / hr as it was found that such flow speeds are beneficial to acquire a high efficiency.

[0083] In the system shown in figure 1, a first exhaust 40 is arranged at a first position above support 13. A second exhaust 41 is arranged at a second position lower than the first position. An (optional) third exhaust 42 is arranged at a third position lower than the first and second position. This way, airflow with evaporated volatile components is received from different locations within the system and can be extracted via ducts 50 and delivered to liquid collection means 20.

[0084] The ducts 50 may be provided with one or more restrictor plates 52, 53. Figure 3 shows a first restrictor plate 52 arranged in the duct connecting the first exhaust 40 (also called manifold) to the liquid collection means. A second restrictor plate 53 is arranged in another duct connecting the second exhaust 41. The restrictor plates may be arranged in any suitable manner so as to regulate the flow with the ducts 50. This way, suction force may be regulated and set as desired so as to provide more suction force at locations needing more extraction of volatile components. The restrictor plates may equally be included in the example shown in figure 4.

[0085] Figure 4 illustrates an example of a thermal development means 10 with more detail. The development means may be the same as the development means explained in connection to figure 3. The thermal developing means having a heater 11, a developer 12 and a support 13. The heater is configured for heating and optionally (pre)liquefying parts of the relief precursor RP. The heater may be an IR lamp, a means for delivering a hot gas or liquid stream, a hot surface or a combination thereof.

[0086] The developer 12 is configured and arranged for removing liquified parts from the relief precursor. The support 13 is arranged for supporting the relief precursor, in particular such that a counter pressure may be provided when a heating roll 12a of the developer is pressed against the relief precursor (not shown in figure 4). The support 13 as shown is a rotating drum which optionally has an active cooling system for cooling the backside of the relief precursor.

[0087] Preferably, the heating roll 12a of the developer 12 has a radius of curvature in the range from 20 to 360 mm, in particular at a location where the support makes contact with the developer. The contact location is indicated via 13a. Such curvature has been found to result in relief structures with desired properties. The drum 13 preferably has a compressible layer with a compression modulus between 10 and 20000 kPa to achieve an increased performance of the developed relief structures obtained.

[0088] It is understandable that developer 12 may be configured in any suitable manner, for example as comprising one or more of: a rotating drum, an endless belt, a (oscillating) flat or curved bed, a (oscillating) belt, a brush, a rotating brush or any combination thereof. The developer 12 has or is configured to receive a web 12a made with material capable of removing, absorbing or adsorbing liquefied material of the relief precursor.

[0089] Figure 4 further shows at least exhausts 40, 41, 44 which are positioned for receiving (contaminated) airflow which is generated upon heating the relief precursor with heated roll 12a. The exhausts 40, 41, 44 are arranged at different positions so as to receive the generated contaminated air from different locations. In this manner, the contaminated air with the volatile components may be transported via ducts 50 to the liquid collection means 20. Preferably, the one or more ducts 50 are provided with one or more drains 51 for draining liquids from the ducts. Typically, the transport of the airflow with the volatile components in the ducts 50 is facilitated by an attracting flow or suction force created by one or more vanes of the liquid collection means 20 in addition thereto, fans and / or blowers may be provided.

[0090] The ducts 50 are configured to allow airflow with the evaporated volatile components flowing from the exhausts 40, 41, 42 to the liquid collection means 20 through the one or more ducts 50 at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr.; most preferably 600 - 800 m3 / hr as measured at the inlet of the collection means 20. The flow speeds within each duct may be set as desired by arranging one or more restrictor plates 52, 53, 54. If liquids where to be formed in the ducts, these may be drained via drain 51. The drain is preferably positioned such that liquids in the duct 50 flow to the drain upon influence of gravitation.

[0091] Figure 5 illustrates a preferred embodiment of the liquid condensation means 20. The figure shows the liquid collection means 20 having a rotor 21 provided with vanes 22. The vanes 22 preferably extend inwardly from (inner) sidewalls of the rotor 21 towards the rotational axis ca. Other configurations of the vanes may be possible as long as the vanes impact airflow AFC with volatile components such that droplets with volatile components are formed on the impact surface of the vanes. This way, at least some, preferably all volatile components are separated from the airflow such that airflow AF is purified. The rotor 21 is configured such that the droplets are shed off from the impact surface 22 and forced against the outer rotor housing 23 using centrifugal force. The components C may then be removed via outlet 24 and optionally be collected in a container 25 (not shown in figure 5).

[0092] The airflow AFC may be delivered to the liquid collection means in any suitable manner, preferably via the one or more ducts 50 (as explained earlier above). The vanes 22 can be configured such that a suction force is created upon rotation of the vanes. This way, the airflow AFC may be extracted and from within the system and be attracted to the liquid collection means 20.

[0093] The vanes may extend in any radial direction, though preferably the vanes extend towards central rotational axis ca. The rotor 21 is preferably a perforated drum having sidewalls from which the vanes extend in inward direction towards the rotational axis.

[0094] Figure 5 shows housing 23 having the rotor 21 rotationally arranged therein the housing.

[0095] The housing 23 is configured to guide the obtained liquid to the outlet 24 to allow removal of the liquid from the collection means. The housing is preferably cylindrical. The housing may further be formed as an assembly (not shown) having an upper housing part and lower housing part, which are removably connected to each other. This way, the housing 21 may be opened so as to provide easy access to components within (such as the rotor) if cleaning or maintenance would be required.

[0096] A peripheral channel 28 is defined between the housing 23 and the rotor 21 which is configured to guide liquid to the outlet 24. The liquid may then be guided to a container (not shown). Figure 5 further illustrates that housing 23 is provided with a catch rib 23a. The catch rib is configured to catch and guide liquid to the outlet 24. This way, the liquid with the components C can be disposed. The outlet 24 may deliver the liquid with the components to a container 25 configured to allow easy removal. The catch rib is arranged on the inside of housing 23 and can have any shape, such as an L or U shape to catch and guide liquid to the outlet 24. Preferably, the catch rib 23 extends along the whole inner circumference of the inner side wall. The housing may have a lower part with an inlet for receiving contaminated airflow AFC. The housing 23 may further have an upper part. The catch rib 23 is positioned in the upper part of the housing 23. Figure 5 further shows that, as seen in a length direction, the rotor is arranged between the inlet 26 and outlet 24. With other words, the inlet 26 is upstream of rotor 23 and the outlet 24 is downstream thereof.

[0097] The catch rib 23a is arranged downstream of the outlet 24 and arranged so as to catch and guide liquid to said outlet 24.

[0098] Figure 5 further shows an optional second outlet 29. The second outlet 29 is configured to allow additional removal of liquid from the collection means 20. Preferably, the second outlet is arranged at the lower part of the housing 23, preferably at the bottom such that liquids may be removed.

[0099] Preferably, the second outlet 29 is arranged at a position in the housing so as to allow removal of liquid via gravitational force. The outlet 24 is typically arranged further upstream from the second outlet 29.

[0100] The rotor 21 may be arranged according to any suitable arrangement with respect to the gravitational force, preferably such that the rotational axis ca is extends in the same direction as the gravitational force.

[0101] Figure 5 illustrates the rotor 21 as having a drum with holes, the side walls thereof are provided with openings 21b. The openings 21b (or holes) are distributed across the drum which preferably has a cylindrical shape. The openings 21b may be provided as having any suitable shape or pattern of openings (also called perforations). The perforations may be provided via any suitable technique and can have any shape (such as a slit or circular shape). Any shape is possible as long as liquid on the vanes 22 can pass through and be forced against outer housing 23. Preferably, the openings 21b have a pattern of holes or perforations, wherein the perforations are substantially circular, preferably having a diameter between 0,5 to 2 cm.

[0102] Figure 5 illustrates with use of arrows that the airflow AFC with the components to be separated from the air such that air AF is purified. By having the rotor 21 to rotate around its central axis ca such that liquid on the rotor 21, in particular liquid on the vanes 22, is forced outwardly against housing 23 by a centrifugal force. In case the one or more vanes 22 are provided with perforations 21b, the liquid may be forced through said perforations. The vanes 22 are arranged such that they generate a flow (or a suction force) for attracting the airflow AFC with evaporated volatile components upon rotation of the rotor. The rotation of rotor 21 is indicated in counterclockwise direction with an arrow. Off course, clockwise direction is also possible. The rotation may be controlled in any suitable manner by a control means 60. The rotor 21 is preferably configured so as to generate a flow attracting contaminated air AFC from the system, said flow AFC having flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr, most preferably 600 - 800 m3 / hr. The vanes are configured to attract the airflow AFC via ducts 50. A safety grid (not shown) may be provided between ducts 50 and the liquid collection means and / or between the ducts and rotor 21.

[0103] The rotation of the rotor 21 may be provided via any suitable means, such as a motor 50, preferably an electric motor. The motor may generate rotational speeds sufficient for attracting contaminated air AFC from the system. The motor may be controlled via control means 60 in any suitable manner so as to control the rotational speed of the rotor 21. Preferred rotational speeds are speeds of more than 800 rpm, preferably more than 1000 rpm, preferably more than 1500 rpm, more preferably speeds between 800 rpm - 4000 rpm, such as between 2500 - 4000 rpm.

[0104] Figure 5 further illustrates silencer 80 arranged downstream of the rotor. The silencer is preferably configured to suppress noise from the rotor. The silencer may be a foam, such as a polyether foam. The silencer may also comprise or consist of a metal and a silencing wool. By including the silencer, comfort of nearby operators may be improved.

[0105] Figure 5 shows rotor 21. The rotor 21 is shown to have an inner wall 21c. The inner wall may made from and / or covered with a porous material, such as an open cell foam, a porous film, a porous metal, a metal wool, a woven or a non-woven material. Figure 6 illustrates schematically an apparatus 1000 for treating a relief plate precursor, such as a printing plate precursor RP (also indicated with P). The apparatus is for instance a washing apparatus for washing and / or solvent developing the relief plate precursor with a liquid (also called washing liquid or developing liquid). Also other treatments are possible such as brushing, rinsing, spraying, drying, irradiating, thermally developing, heating, cooling, removing of material of the relief plate precursor, treating the relief plate precursor with gases or liquids, sanding the relief plate precursor, cutting the relief plate precursor, treating it with electromagnetic waves, or combinations thereof. Further details are of the apparatus are described in WO2021198012, in particular in connection to pages 9 - 11. Figure 6 further illustrates the apparatus being provided with liquid collection means 20, exhaust 40 (may also be called manifold) and duct 50 which may have on or more of the features as already described above. Upon washing of the plate, some components (indicated with AFC) may evaporate from the washing liquid (not shown) and can then be collected with liquid collection means 20 via exhaust 40.

[0106] Figure 7 shows liquid collection means 20 which may have one or more of the features as described herein. The collection means may be connected to the one or more exhaust (not shown) as explained above to receive airflow AFC, e.g. via inlet 26. As mentioned earlier, volatile components within the airflow AFW are captured by the liquid collection means 20 and can be extracted via outlet 24. The extracted stream Cgl from outlet 24 may comprise a mixture of liquid and gas, such as air.

[0107] Preferably, the system is further provided with a gas liquid separator 90 arranged downstream of the liquid collection means 20 and configured to receive a stream with condensated volatile components Cgl from outlet 24.

[0108] Figure 7 illustrates that the gas liquid stream Cgl which is given to the separator 90 is separated in a gas stream Cg and a liquid stream Cl. Preferably, the gas liquid separator 90 is connected to the outlet 24 to receive the gas liquid stream Cgl therefrom. Preferably, the separator 90 is configured to deliver the liquid stream Cl to the container 25 such that the liquid can be stored therein. The separator 90 may be configured to exit the stream Cg directly to the surrounding environment or may be configured to feed the stream Cg back to the liquid collection means 20.

[0109] The stream Cg may exit the system directly (not illustrated), e.g. via exit outlet 62, or may first be fed back to the liquid collection means 20. Any suitable feedback arrangement may be used such that the stream Cf is fed back before being exited from the system, e.g. via final exit outlet 62. Preferably, the separator 90 is configured to feed the gas stream Cg back to the liquid collection means 20. Preferably, the gas stream Cg is fed to the silencer 80 and / or upstream thereof (illustrated with the arrows) so as dampen noise generated by said stream. In this manner, comfort of nearby operators is improved.

[0110] The skilled person will appreciate based on the above description that the invention can be embodied in different ways and on the basis of different principles. The invention is not limited to the abovedescribed embodiments. The above-described embodiments and the figures are purely illustrative and serve only to increase understanding of the invention. The invention will not therefore be limited to the embodiments described herein but is defined in the claims.

Claims

CLAIMS1. A system (1) for developing a relief precursor, said system comprising: a development means (10) configured for developing the relief precursor so as to obtain a developed relief structure, such as a printing plate; at least one exhaust (40, 41, 42) for receiving an airflow with evaporated volatile components generated during development of the relief precursor; a liquid collection means (20) connected to the at least one exhaust, said liquid collection means being configured to condensate evaporated volatile components to obtain a liquid, wherein the liquid collection means (20) is configured to collect the liquid with evaporated volatile components using centrifugal force.

2. The system according claim 1, wherein the system is a system for thermally developing the relief; wherein the development means is a thermal development means (10) configured for heating the relief precursor and for removing liquified portions of the heated relief precursor to obtain the developed relief structure; and wherein the evaporated volatile components are generated during heating of the relief precursor.

3. The system according to any of the previous claims, wherein the liquid collection means (20) is provided with an outlet (24) configured to allow removal of the collected liquid from the collection means.

4. The system according to any one of the previous claims, wherein the liquid collection means (20) comprises a rotor (21) with one or more impact surfaces (22) to impact the airflow with the evaporated volatile components such that droplets with the volatile components are formed on the impact surface, and wherein the collection means are preferably configured to shed off the droplets from the impact surfaces using centrifugal force.

5. The system according to the previous claim, wherein the one or more impact surfaces (22) of the rotor (21) extend in a radial direction, preferably towards a central rotational axis (ca) of the rotor.

6. The system according any of the previous two claims, wherein the liquid collection means (20) comprises a housing (23), such as a cylindrical housing, wherein the rotor (21) is rotationally arranged within the housing;wherein the rotor is configured to rotate around its central axis (ca) such that liquid on the rotor is forced outwardly against the housing by a centrifugal force.

7. The system according to the previous claim and claim 3, wherein the housing (23) is configured to guide the obtained liquid to the outlet (24) to allow removal of the liquid from the collection means.

8. The system according to the previous claim, wherein a peripheral channel (28) is defined between the housing and the rotor, said channel being configured to guide liquid to the outlet.

9. The system according to the previous claim, wherein a catch rib (23a) is arranged within the peripheral channel and is configured to catch and guide liquid to the outlet (24).

10. The system according to any of previous claims 4 - 9, wherein the rotor (21) comprises a cylindrical drum (21a) having openings (21b) for allowing liquid to pass through upon rotation of the rotor; wherein the openings are for example formed as a pattern of holes distributed across the cylindrical drum.

11. The system according to any of previous claims 4 - 10, wherein the rotor (21) comprises one or more vanes (22) for impacting the evaporated volatile components; and wherein the vanes are arranged such that they generate a flow for attracting the airflow with evaporated volatile components upon rotation of the rotor.

12. The system according to the any of previous claims 4 - 11, wherein the rotor (21) is configured to rotate at speeds of more than 800 rpm, preferably more than 1000 rpm, preferably more than 1500 rpm, more preferably speeds between 800 rpm - 4000 rpm.

13. The system according to the any of previous claims 4 - 13, wherein the rotor (21) has an inner wall (21c) made from and / or covered with a porous material, such as an open cell foam, a porous film, a porous metal, a metal wool, a woven or a non-woven material.

14. The system according to the any of previous claims 4 - 13, further comprising a control means (60) configured to control a rotational speed of the rotor (21) of the liquid collection means (20).

15. The system according to any of the previous claims, wherein the system is further provided with a silencer (80) arranged for silencing noise from the liquid collection means (20), such as noise from a rotor, said silencer preferably comprising a foam, such as a polyether foam.

16. The system according to any of the previous claim, wherein the liquid collection means (20) is arranged at a position higher than the development means (10), preferably at least 0.5 meter higher, more preferably at least 1 meter higher.

17. The system according to any of the previous claims, further comprising a container (25), preferably a removable container, for collecting liquid comprising the volatile components.

18. The system according to any of the previous claims, further comprising one or more ducts (50) connecting the at least one exhaust (40, 41, 42) to the liquid collection means (20).

19. The system according to the previous claim, wherein the one or more ducts (50) are provided with one or more drains (51) for draining liquids from the ducts.

20. The system according to any of claims 18 - 19, wherein the system is configured to have the airflow with the evaporated volatile components flowing from the exhaust to the liquid collection means through the one or more ducts (50) at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr.

21. The system according to any of the previous claims, wherein the at least one exhaust (40, 41, 42) for receiving the airflow with evaporated volatile components comprises: a first exhaust (40) arranged at a first position; a second exhaust (41) arranged at a second position; an optional third exhaust (42) arranged at a third position; wherein the first and second position are chosen such that an airflow with evaporated volatile components is received from different locations.

22. The system according to any of claims 18 - 21, further comprising one or more restrictor plates (52, 53) arranged in the one or more ducts (50) connecting a respective exhaust (40, 41, 42) to the liquid collection means (20); wherein preferably at least two restrictor plates are arranged within at least two ducts so as to regulate a relative flow speed within the atleast two ducts.

23. The system according to claim 2 and any of the previous claims, wherein the thermal development means (10) comprises: a heater (11) configured for heating the relief precursor; said heater preferably being chosen from: an IR lamp, a means for delivering a hot gas or liquid stream, a hot surface or a combination thereof; a developer (12) arranged for removing liquified parts from the relief precursor; a support (13) for supporting the relief precursor; said support preferably being chosen from: a rotating drum, an endless belt, a flat or curved bed, an oscillating belt or a combination thereof.

24. The system according to the previous claim, wherein the developer (12) has a heating roll (12a) which has a radius of curvature in the range from 20 to 360 mm.

25. The system according to any of the previous two claims, wherein the support (13) and / or the developer (12) are provided with a compressible layer, preferably with a compression modulus between 10 and 20000 kPa at least at the location where the support and the developer make contact with each other.

26. The system according any of the previous three claims, wherein the developer (12) comprises one or more of:- a rotating drum, an endless belt, a (oscillating) flat or curved bed, a (oscillating) belt, a brush, a rotating brush or any combination thereof;- a material capable of removing, absorbing or adsorbing liquefied material of the relief precursor, said material preferably comprising a film of a woven or nonwoven material, a natural or an artificial polymer, a paper, a metal, a composite or combinations thereof;- a surface for coming into contact with the relief precursor, said surface being provided with a metal, an alloy, a glass, a ceramic, a polymer, a composite or combinations thereof.

27. The system according to any of the previous claims, further comprising a gas liquid separator (90) arranged downstream of the liquid collection means (20) and connected thereto so as to receive a stream (Cgl) exiting the liquid collection means, wherein theseparator is configured the separate a liquid from a gas.

28. Use of a moving impact surface, such as a surface a vane (22), for collecting volatile substances arising from a relief precursor (RP) during the developing thereof, said moving preferably comprising a rotation of the impact surface.

29. A method of thermally developing a relief precursor, the method comprising the steps of:- providing a relief precursor;- heating the relief precursor and removing liquified portions of the heated relief precursor, so as to obtain a developed relief structure, such as a printing plate;- collecting evaporated volatile components from an airflow by impacting said airflow with evaporated volatile components against an impact surface (22) such that a liquid is formed on said impact surface and subsequently collecting said liquid, wherein the liquid with the components is collected using a centrifugal force.

30. A method of solvent developing a relief precursor with a solvent, the method comprising the steps of:- providing a relief precursor;- developing the relief precursor by removing portions of the relief precursor with a solvent, so as to obtain a developed relief structure, such as a printing plate;- collecting evaporated volatile components from an airflow by impacting said airflow with evaporated volatile components against an impact surface (22) such that a liquid is formed on said impact surface and subsequently collecting said liquid.

31. The method of the previous claim, wherein the liquid with the components is collected using a centrifugal force.

32. The method according to any of the previous method claims, wherein the impact surface is a vane (22) of a rotor (21), wherein the method further comprises:- rotating the rotor at speeds of more than 800 rpm, preferably more than 1000 rpm, preferably more than 1500 rpm, more preferably speeds between 800 rpm - 4000 rpm, such as between 2500 - 4000 rpm.

33. The method according to any of the previous method claims, comprising:- transporting the air with evaporated volatile components from an exhaust (40, 41, 42) for receiving an airflow with evaporated volatilecomponents generated during development of the relief precursor to a liquid collection means (20) configured to condensate evaporated volatile components to obtain a liquid; wherein the air is preferably transported at flow speeds between 50 to 3000 m3 / hr, preferably between 100 - 2900 m3 / hr, more preferably 100 - 1500 m3 / hr, most preferably 600 - 800 m3 / hr.

34. The method according to any of the previous method claims, wherein the relief precursor (RP) comprises a photosensitive layer (PL) supported by a mechanically stable support layer (SL).

35. The method according to any of the previous method claims, wherein collecting the liquid comprises collecting the liquid in a container.

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