METHOD AND MEANS FOR RECYCLING UNUSED MATERIAL

Abstract: Method and apparatus for making up a specific quantity of mass for a desired composition with re-use of residual masses. The method comprises the steps of determining whether at least one residual mass can be selected from a plurality of residual masses and adding base components in order to obtain the specific quantity of mass of a desired composition. The method comprises the further steps of storing the plurality of residual masses, including associated containers, in a warehouse (13) and, if one residual mass can be selected, selecting the associated container in the warehouse (13) for use as container for the mass to be made up. The method is used in an apparatus (10) comprising the warehouse (13) for storing containers containing residual mass, a transport device (14) for transporting containers into the apparatus (10) and a metering device (16) for adding base components.

Description: METHOD AND MEANS FOR RECYCLING UNUSED MATERIAL The present invention relates to an apparatus and method for making up a specific quantity of mass of a desired composition from at least one base component with re-use of residual masses which consist of at least one base component, comprising the steps of determining whether at least one residual mass can be selected from a plurality of residual masses stored in a warehouse and adding base components in order to obtain the specific quantity of mass of a desired composition, An apparatus and method of this type are disclosed in European Patent Application EP-A 0 735 954. This patent application describes a method, apparatus and program for the preparation and delivery of a mass that consists of a plurality of base components, with re-use of previously made-up and returned mass. This is used inter alia for the preparation and delivery of fluid or paste-like coloured masses, for example printing pastes for printing textiles. The mass to be delivered is made up of residual masses having specific characteristics, which are stored in a warehouse in special storage containers. Residual products from a printing process are returned to the warehouse and combined in collection containers depending on the composition of the base components. To make a new stock of mass of a specific, desired composition ready for use, some of a residual mass is siphoned from a collection container into a new container and ma e up with further base components to give the desired composition. A disadvantage of the known method and apparatus is that residual masses are collected in a limited number of collection containers. This limited number of collection containers means that not all residual masses of different compositions can also actually be collected and re-used. A limited number of collection containers to be used thus leads to a lower percentage re-use, A further disadvantage of the known method and apparatus is that the preparation of a fresh mass demands many cleaning steps. In the known method each bucket, each can or each other container that contains residual mass and is submitted for re-use must be emptied into a specific collection container in the warehouse. This means that each returned container has to be scraped out and cleaned. Scraping apparatuss, which have to be cleaned after each scraping operation, are often used. Moreover, it will not be possible to transfer all residual mass from the returned containers to one of the collection containers. All of this leads to an additional reduction in the percentage reuse and to pollution of the environment and demands additional processing time. If, for example, 240 containers containing residual mass are input in one day and 100 g residual mass remains behind in each container after scraping out, this means that there are 240 washing operations per day, 24 kg residual mass being lost. A further disadvantage of the known method and apparatus is that, because the collection containers contain batches of residual mass which can have compositions that differ from one another, the residual masses collected in the collection containers demand an additional homogenisation treatment before the residual mass concerned can be re-used for making up a new mass. Because of the large dimensions of the collection containers, more mass will remain behind when the collection container is completely emptied. These virtually empty collection containers will also have to be regularly cleaned, which, in turn, demands additional processing time and leads to further environmental pollution. This thus leads to an additional loss of residual mass, as a result of which the percentage re-use becomes lower. In practical embodiments of the known apparatus, residual mass will be collected in containers only if the composition of the residual mass meets certain conditions in respect of composition of base components. If the composition of the residual mass docs not meet these conditions, the residual mass concerned will not be added to a collection container but will be thrown away. This leads to a further adverse affect on the percentage re-use and on the environment. The aim of the present invention is to provide a method and apparatus for making up a specific quantity of mass making use of residual masses, which optimises the reuse of residual masses and is environmentally friendly, A further aim relates to limiting the environmentally polluting washing operations as far as possible. These aims are achieved by a method of the type defined m the preamble, wherein the method comprises the further steps of storing the plurality of residual masses, including associated containers, in the warehouse and, if one residual mass can be selected, selecting the associated container in the warehouse for use as container for the specific quantity of mass to be made up. The advantage of the present method is that as a result of the use of a container containing residual mass for a new quantity of mass to be made up it is not necessary to use an empty container, which renders a washing treatment of the container containing residual mass superfluous. This has a beneficial effect on the environmental pollution caused by the present method. As a result of the storage of residual masses with associated container, the containers do not have to be emptied into (large) collection containers. This saves time and makes washing of the containers superfluous. In one embodiment the present method comprises the f-ιrther step of selecting a container from a buffer store of empty containers for use as container for the specific quantity of mass to be made up if there is no suitable container in the warehouse. If it is found that re-use of residual mass in the residual mass store is not possible, or because other criteria prevent this, in this embodiment it is possible to take an empty container in which the quantity of mass to be made up is prepared. In a further embodiment at least one further residual mass is selected from the warehouse and added to the one container. The percentage re-use will be further increased by this means. The one container can be a container containing residual mass or an empty container from the buffer store. The present method can advantageously be used for the preparation of inks or pastes for the printing industry, such as fluid or paste-like printing ink. The selection of the first container containing residual mass and optionally further containers coaxaiπmg residual mass from the warehouse is preferably carried out on the basis of at least one criterion. In the case of selection of the first container containing residual mass, the criterion for selection of the first container is preferably correspondence of a desired type of container with the type of container of the one container. The criterion can also be the presence in the residual mass of at most all base components of he desired composition. Preferably a residual mass that has exactly the same base components as the desired composition is re-used. After all, such a residual mass is more difficult to re-use than a residual mass containing a smaller number of base components corresponding to the desired composition. If a residual mass contains fewer base components it can be used for a greater number of different desired compositions. In a further embodiment of the present invention the method further comprises the step of calculating a mass change factor, defined as the highest value of the ratio of each base component in the residual mass and the desired mass, and the at least one criterion comprises the lowest value of the mass change factor. The lowest mass change factor means that the smallest amount of additional base components has to be added to the residual mass, so that the residual mass is re-uscd in the most efficient manner. As an alternative, the criterion comprises the lowest value of the product of the mass change factor and a weight of the residual mass. This means that the smallest individual quantities of residual mass of a suitable composition will be re-used first, which also has a beneficial effect on the percentage re-use. This alternative is preferably used if the warehouse is filled in excess of a predetermined percentage. After all, with this criterion for use, as many containers as possible containing residual mass are re-used. In a further embodiment the criterion comprises the historical re-use of a specific composition. For instance, preference can be given to a residual mass of a specific composition which historically rarely occurs (and is thus difficult to rc-use) over a residual mass of a composition that from fhe historical standpoint frequently occurs. Ultimately this will lead to a more favourable percentage re-use. The shelf life of the at least one residual mass that is predicted on the basis of a shelf life model of the base components which are contained in the at least one residual mass can also be used as criterion. As an alternative, the shelf life can be predicted on the basis of a shelf life model of the combination of base components which is contained in the at least one residual mass or on the basis of a shelf life model of the at least one residual mass in the associated container. In general the shelf life model is a function of time and ambient temperature. In the majority of cases a limited time is available for making up a specific quantity of mass, certainly when different quantities have to be made up in succession. The criterion that is then used is the time that is required for making up the desired mass with re-use of residual masses. This time is taken up by collecting the first container cont-u ' ning residual mass from the warehouse and, if necessary, adding further residual masses thereto. A further criterion can be that a certain minimum fraction of the residual mass in an associated container can be re-used. In this way too much time is prevented from being spent on the (partial) re-use of a specific residual mass. In yet a further embodiment the residual masses, with associated container, are positioned in the warehouse depending on the frequency with which the composition of the residual mass occurs. By placing residual masses of a frequently used composition as close as possible to further processing apparatuss it is possible to save time when preparing new masses. In a further alternative the method comprises the further step of scraping out the container containing residual mass, the residual mass being collected in a residue container for a specific colourant group. This residual mass can then be rc-used as residual black, for example by adding a large quantity of black colourant to the residue container. By this means it is also possible to process small losses, for example as a consequence of shelf life, and re-use them. In a further aspect the present invention relates ιo an apparatus for making up a specific quantity of mass of a desired composition from at least one base component with re-use of residual masses which consist of at least one base component, comprising a warehouse for storing containers containing residual mass, a transport device for transporting containers containing residual mass into the apparatus and a metering device for adding base components in order to obtain the specific quantity of mass, the transport device and the metering device being connected to and controlled by a control device which is equipped to carry out the method according to the present invention. This apparatus makes effective re-use of residual masses possible, whilst the number of washing operations required remains very restricted. Preferably, the apparatus further comprises a combining station for combining residual masses from various containers containing residual mass. By this means it is possible effectively to re-use further containers containing residual mass from the warehouse. In addition, the apparatus preferably further comprises a washing station for containers. In a further embodiment the apparatus according to the present invention further comprises a reception station for containers containing residual mass. With the aid of the transport device, containers containing residual mass which are submitted at this station can be stored in the warehouse. Preferably, the reception station comprises further devices for the identification and characterisation of a container and the residual mass contained therein. The data on the containers and the residual mass contained therein are then used in order to determine which containers) can be re-used for a new quantity of mass of a desired composition that is to be made up. In yet a further aspect the present invention relates to a computer-readable medium, such as a floppy disk or CD-ROM that contains instructions that can be executed by a computer in order to carry out the method according to the present invention. The present invention will now be explained in more detail with reference to preferred embodiments of the method and apparatus, with reference to the appended drawings, in which: Fig. 1 shows a diagrammatic view of an apparatus according to one embodiment of the present invention; Fig. 2 shows a block diagram of the control for the apparatus in Fig. 1; and Fig. 3 shows a flowchart of a preferred embodiment of the method according to the present invention. The present invention relates to a method and apparatus for making up a quantity of mass comprising of a number of base components, such as printing paste for textile printing. Printed textiles are used for the manufacture of fashionable clothing, furniture and curtains. In textile printing viscous printing paste is applied to a material or paper substrate by means of screen printing technology. In the case of a paper substrate, the printing paste is transferred again to a material substrate in an additional process step (transfer printing). A number of screen printing stencils with different colours lead to the final printed textile. Printing paste of a specific colour is needed for each screen printing stencil. This printing paste is made up of a mixture of base colours (usually a maximum of three in practice), thickener and other chemicals. The thickener provides the viscous nature of the printing paste that is required for screen printing- The chemicals give the printing paste further required characteristics, such as adhesion to the textile. The preparation of the printing pastes is usually carried out in a so-called paint kitchen where mixtures are made up by mixing the correct quantities of colourants, thickener and chemicals. The printing paste is prepared in a container and then transported to the printing machine. The required quantities of a printing paste of a specific colour vary from ten kg to a few hundred kg. Because it is often difficult to estimate precisely how much printing paste is required for a specific production run, frequently somewhat more printing paste is made up than is indicated by calculations. This prevents a shortage of printing paste leading to an incorrect printed image or to a halt in production. The consequence of this is, in turn, that a certain percentage of each quantity of printing paste made up is left over, the so-called residual mass. In some printing systems there is a facility for also recovering the equipment fill (the quantity of printing paste that is present in lines and the like in the printing apparatus). In practice about 20 - 25% of the printing paste originally prepared is left over. The costs of destroying this residual mass are high and the residual mass is also highly polluting for the environment. The present invention provides a method and apparatus for the efficient and simple re-use of a quantity of residual mass comprising of at least one base component, such as printing paste. Re-use of residual masses is optimised by the administration and anticipation of a history of previously prepared masses in combination with shelf life aspects of the base components used. A further advantage of the present invention is that a minimum number of washing operations take place, which gives rise to lower environmental pollution and a faster processing time. Existing automatic re-use apparatuss have the disadvantage that they have a high purchase price and high maintenance costs, that they take up a great deal of space and that the percentage re-use is limited. Fig. 1 shows a diagrammatic representation of one embodiment of the apparatus 10 according to the present invention. Buckets containing residual mass are fed into the apparatus 10 at the reception station 11. This reception station 11 can be a simple table, but can also be a conveyor belt with a number of further devices. These further devices can consist of a device for automatic determination of the composition of base components (which base components are present and in what proportion) of the residual mass and/or scales for determining the weight of the residual mass. The further device can also be a device for identifying the type of bucket. If a note is made of the composition of the mass in a specific bucket when the specific bucket is prepared, this can be entered as information in the apparatus 10 when this bucket (now) containing a residual mass is returned, after identification of the bucket. The buckets containing residual mass that are to be accepted are brought by a transport device 14 (for example a warehouse fork lift truck) from the reception station 11 to a residual mass store 13, for example in the form of two warehouse racks 1 , for storage. The apparatus 10 records exactly in which location which bucket containing residual mass is stored. The apparatus 10 can also comprise a buffer store 12 (preferably various buffer stores 12a, 12b for different types of bucket), in which empty buckets of a specific type are stored. The empty buckets can be moved into the further apparatus 10 with the aid of the transport device 14. As an alternative, the empry buckets are also stored in the warehouse 13 and storage of the empty buckets proceeds via the reception station 11. In the most ideal situation the apparatus 10 will fetch a specific bucket containing residual mass from the residual mass store 13 with the aid of the transport device 14 for re-use of both the bucket and the residual mass contained therein for the preparation of a bucket containing a desired quantity of fresh mass. The transport device 14 delivers the bucket containing residual mass onto a conveyor belt 15 for further processing. Preferably, buckets containing a residual mass having a composition that is frequently used are placed in such a position in the residual mass store 13 that the collection and transport of such a residual mass requires as little time as possible, for example by placing such a residual mass close to the conveyor belt 15, In some cases one or more further buckets containing residual mass will be added from the residual mass store 13 to the first bucket containing residual mass. The apparatus 10 has a special conveyor belt IS and a combining station 19 for this purpose. The further bucket containing residual mass is placed by the transport device 14 on the special conveyor belt 18 and the combining station 19 empties the further bucket into the first bucket standing ready on the conveyor belt 15, for example using a scraping device known per se. The additional mass added is recorded with the aid of scales 20 in the combining station 19. The further bucket is then brought by the special conveyor belt 18 to a washing station 21, where the further bucket is cleaned. After treatment in the washing station 21, the empty further bucket is available for re-use, for example via storage in the buffer store 12. In an alternative set-up the further bucket to be emptied is not scraped out into the first bucket but the residual mass is scraped out into a funnel (not shown), after which the residual mass is pumped into a container. This container collects all residual masses that belong to a given colourant group or chemical application. The system can use various colourant groups (pigment, reactive, disperse, vat dyes) and the system has a funnel and container per colourant group. The residual mass in each of these containers can be used as residual black, After collecting, a large quantity of black colourant is added, as a result of which the colourants present in the container are no longer recognisable. This residual black can be used, for example, when printing contours or thin lines- where loss of colour is not so important. After the specific first bucket containing residual mass has been placed on the conveyor belt 15 by the apparatus 10 and any further buckets containing residual mass have been added with the aid of the combining station 19, the first bucket is further transported by the conveyor belt 15 to a metering device 16. The metering device 16 adds the further required base components in order to t obtain the desired quantity of mass of the desired composition. The bucket containing the desired quantity of mass is available at the output 17 of the metering device 16 for further transport to the printing apparatus (not shown). If, according to the method, only part of a bucket containing residual mass can be re-used for a desired quantity of mass of a specific composition, the apparatus 10 can collect an empty bucket from the buffer store 12 by means of the transport device 14 and place it on the conveyor belt 15. In the combining station 19, part of the residual mass is then emptied from a bucket into the empty bucket that has been placed ready. The remainder of the residual mass and associated bucket can then be replaced in the residual mass store 13 with the aid of rhe conveyor belt 18 and the transport device 14. Of course, it is also possible that the desired quantity of new mass makes it impossible to re-use buckets containing residual mass that are present in the residual mass store 13. In this case an empty bucket is brought directly to the metering device 16, where the desired mass is prepared. In an alternative embodiment of the apparatus shown in Fig. 1 the combining station 19 is placed close to the residual mass store or warehouse 13. In the set-up shown in Fig. 1, emptying buckets takes time and during that time other buckets cannot be removed (via the conveyor belt 15 to metering device 16), By now locating the combining station 19 in the warehouse 13 it is possible to carry out these processes in parallel (combining buckets and setting buckets down). Preferably, the washing station 21 and associated conveyor belt IS is still set up in the vicinity of the combining station 19. Fig. 2 shows a block diagram of a control device for the apparatus according to the present invention. A control device 23 is connected to and receives information from the reception station 11, the scales 20 of the combining station 19 and an input device 22, such as a keyboard. Information relating to a bucket containing residual mass that is submitted at the reception station 11 is fed to the control device 23 by the abovementioned further devices (data relating to composition and weight of residual mass and the type of bucket) or entered via the input device 22, As an alternative the control device 23 receives information relating to the composition of the contents of a specific bucket from the metering device 16. The buckets containing residual mass are preferably provided with identification, so that it is possible to follow the individual buckets in the apparatus 10. When the specific bucket is then identified by the reception station 1 the composition of the contents thereof is already known. The control device 23 is equipped to carry out the method according to the present invention. To this end the control device 23 comprises, for example- a P C control system or a control system based on a microprocessor and the control device is further provided with suitable memory means. Furthermore, the control device 23 is connected to the transport device 14, the combining station 19, the washing station 21 and the metering device 16 and is equipped to control these in the correct manner. Of course, the control device 23 can be equipped to control the conveyor belts 15, IS in the correct manner. As an alternative the metering device 16 receives information from the control device 23 with regard to the composition of the (optionally combined) residual masses and the metering device 16 is further equipped to add base components to the (combined) residual masses so that the desired composition is obtained. A preferred embodiment of the method for re-use of residual masses of, for example, printing paste according to the present invention will now be explained with reference to the flowchart shown in Fig, 3. In block 101 data 12 are entered relating to the quantity of mass that is required and what the desired composition of the base components has to be. The data comprise the total required weight, the composition (the relative proportions of base components) and the desired bucket type. In blocks 102 and 103 it is then determined which bucket will be used as first bucket in the residual mass store 13 or the buffer store 12a, 12b. In the optional block 102 it is determined on the basis of input data whether there is sufficient time to use one or more buckets containing residual mass from the residual mass store 13 for the desired quantity, or whether the time is sufficient only to use an empty bucket from the buffer store 12a, 12b and to fill this in the metering device 16. The data are the maximum permitted time (IS) for the preparation of the residual masses (in most cases the prepared residual masses must be corrected by the metering device 26 and too long a preparation time can give rise to waiting time at the output of the metering device 16), the time that is required for collecting a bucket containing residual mass from residual mass store 13 (110) and the time that is required to add a further bucket contaimng residual mass to a first bucket containing residual mass in the combining station 19 (111). In block 103 it is determined which buckets containing residual mass in the residual mass store 13 contain one or more base components identical to those in the desired mass. The method receives data relating to the buckets containing residual mass in the residual mass store 13 (U). These data comprise the type of bucket E, the total weight of the residual mass, the composition (relative proportions of base components), the colourant' group to which the residua) paste belongs (colourant group is, for example, pigment, reactive, disperse, vat, etc) and the relative age of the residual mass. If the apparatus 10 is equipped with a device for automatic detection of the composition of the residual mass, these data also comprise the recorded spectrum and the associated process parameters (such as substrate, printing process, settings, etc.). Only if there are no buckets in the residual mass store 13 which contain all base components of the desired mass, buckets containing residual masses with fewer base components are selected. The mass change factor is calculated for the buckets containing residual mass that have been found and which all can be re-used as first bucket. This mass change factor indicates the minimum mass (in the form of one or more base components) that has to be added to the residual mass in order to obtain the required composition of the desired mass. The mass change factor (F) is defined as the highest value of the ratio of each base component in the residual mass and the desired mass. If, for example, there is a residual mass containing 2.0 g/kg colour 1, 3,0 g/kg colour 2 and 995.0 g/kg thickener and the desired composition consists of 5 g/kg colour 1, 3.2 g/kg colour 2, 2,8 g/kg colour 3 and 992,5 g/kg thickener, the mass change factor ill be 1,333. The ratios of the base components in the residual mass and the desired composition are, respectively, 2.0/1.5 ~ 1.333 for colour 1; 3.0/3.2 = 0.9375 for colour 2; - for colour 3 (does not occur in old formulation); and 995/992.5 = 1.0025 for thickener. The method calculates and determines the following data for a specific desired composition for each bucket containing residual mass that could be used: the mass change factor F, the bucket type E, a shelf life indicator O and a weight G. The shelf life indicator is derived from the history of the residual mass that is present in the bucket concerned and is a function of time and the ambient temperature. That bucket which firstly is of the correct bucket type and secondly has the smallest mass change factor, that is to say for which the ratio of base components comes closest to the ratio of base components in the desired mass, is chosen from the series of buckets from the residual mass store 13 thai could be used. Preferably, only a bucket containing a residual mass that can be used in its entirety is chosen because in this case not only the residual mass but also the bucket can be re-used. In the case of colour masses the ratio of base colours (usually a maximum of three) determines the so-called 'triangle', or colour triangle. In principle, only residual masses from the desired colour triangle are re-used for a desired colour. If there are no such residual masses, a residual mass containing fewer base components which, however, do occur in the base components to be used for the desired composition can be re-used for the desired composition. The residual mass must never contain base components which do not occur in the desired composition. In a further embodiment of the present method, account is also taken of the re-use history 17 from the apparatus 10, This history comprises data relating to historical reuse of each combination of one or more base components, It is, for example, possible that a certain combination of base components occurs very frequently or very rarely. Depending on this, preference can be given, for example, to a bucket containing a residual mass that has a composition that precisely corresponds to the desired composition rather than a bucket that would make a higher weight possible for re-use. It is also possible that preference is given to the prevention of potential losses of residual mass in connection with the shelf life thereof. As an alternative, re-use history 17 can indicate that optimisation of re-use of all residual masses present in the residual mass store 13 must be disregarded because there is already a question of loss of residual mass in a specific colour triangle (for example as a result of age). In this case preference will be given to re-use of the maximum possible quantity of residual mass in that specific colour triangle, even if this leads to having to start with an empty bucket to which various residual masses are added, The method can also take account of the shelf life of the residual masses present in the residual mass store 1 . The information relating to shelf life can comprise shelf life per base component (13) and shelf life for combinations of base components (14) as a function of time and ambient temperature. The method also uses the historical change in the ambient temperature (16) for this purpose, in order to determine the shelf life for individual buckets containing residual mass. In addition, in the case of the use of printing pastes the progression in the shelf life at the rim and on the base of a bucket can, for example, also be determined (15), In this context the shelf life is dependent, inter alia, on the type of colourant group (pigment, reactive, disperse, vat, etc.). Thus, one bucket that can be re-used together with the residual mass present therein is indicated as result 01 of block 103. This output is used by the control device 23 to control the various components of ϊhe apparatus 30. If there ate no suitable buckets containing residual mass, the result Ol will indicate that an empty bucket of the correct type has to be collected from the buffer store 12. Residual masses are then added to the empty bucket in the combining station 19, or the empty bucket is transported directly to the metering device 16. In a further embodiment of the present method, not only is a first bucket determined from the residual mass store 13, but it is also determined whether several residual masses from further buckets from the residual mass store can be added to the first bucket (block 104). The further buckets are chosen from the possible buckets already identified in block 103. The standard procedure is to select the buckets in ascending order of the value of the mass change factor F. Preferably, the calculation process is used ϊteratively, the quantity of resulting mass and the mass change factor being determined after each addition of a residual mass. As long as there is room for further additions of residual masses in the required weight these will be (partially) added. Further conditions and rules for use can be employed in block 104 for the addition of further buckets containing residual mass. For example, a minimum weight of mass to be added can be set (112). The above mentioned shelf life conditions (13; 14; 15 and 16) can also be applied to the addition of further buckets, just like the conditions relating to treatment time (IS; 110; II 1). In a further embodiment filling of the residual mass store 13 is monitored by the method and an alarm limit is set (Ϊ9). If the alaπn limit is exceeded, the method will attempt to re-use as many individual buckets containing residual mass as possible from the residual mass store 13 for a new mass. This is achieved by selecting on the basis of increasing values of the product of mass change factor F and weight G instead of selecting on the basis of increasing values of the mass change factor F. The method according to the present invention can be further illustrated with the aid of a number of examples. In the first example there are four buckets A, B, C, D present in the residual mass store 13 that contain the same base components as the desired new mass. The desired quantity is 30 kg in a 40 kg type bucket. A number of the data per bucket that the present method uses to determine the selection plan for a first bucket containing residual mass are given in the following table. According to the present method bucket C is chosen as first bucket because the bucket type is correct and this residual mass can be processed in its entirety. Buckets B and D are of the wrong type and therefore drop out. Bucket A drops out because complete re-use would lead to too high a weight (1J * 28 - 30.8 kg). The second example illustrates the sequence of re-use of multiple buckets from the residual store 13, further buckets being added to a first bucket. There are five buckets in the residual mass store 13 that can all be re-used for a new mass (correct bucket type). When drawing up a selection plan according to the normal procedure, the bucket with the lowest factor would be used as first bucket and the sequence of the buckets woul be C, B, E, D, A. If the alarm limit for filling of the residual mass store 13 has been reached, the bucket with the lowest value of kg * factor will be used in the first instance in order to remove as many buckets as possible from the residual mass store 13. The sequence of use is then E, D, B, C, A. If, for example, 20 kg new mass is required, buckets E and D will be processed in their entirety. If the method gives priority to the shelf life, the sequence of re-use will start with bucket A, The other buckets are then used on the basis of other re-use rales.

Claims: CLAIMS 1. Method for making up a specific quantity of mass of a desired composition from at least one base component with re-use of residual masses which consist of at least one base component, comprising the steps of determining whether at least one residual mass can be selected from a plurality of residual masses stored in a warehouse and adding base components in order to obtain the specific quantity of mass of a desired composition. characterised by the further steps of storing the plurality of residual masses, including associated containers, in the warehouse and, if one residual mass can be selected, selecting the associated container in the warehouse for use as container for the specific quantity of mass to be made up. 2. Method according to Claim 1, characterised by the further step of selecting a container from a buffer store (12) of empty containers for use as container for the specific quantity of mass to be made up if there is no suitable container in the warehouse (13). 3. Method according to Claim 1 or 2, characterised in that at least one further residual mass is selected from the warehouse and added to the one container. 4. Method according to Claim 1, 2 or 3, characterised in that the specific quantity of mass is a specific quantity of fluid or paste-like printing ink. 5. Method according to one of Claims 1 to 4, characterised in that the one container is selected on the basis of at least one criterion for re-use of a residual mass. 6. Method according to Claim 5, characterised in that the at least one criterion comprises: correspondence of a desired type of container with the type of container of the one container. 7. Method according to Claim 3 or 4, characterised in that the at least one further residual mass is selected from the warehouse on the basis of at least one criterion for re-use of a residual mass. 8. Method according to Claim 5, 6 or 7, characterised in that the at least one criterion comprises: presence in the residual mass of at most all base components of the desired composition. 9. Method according to one of Claims S to 8, characterised in that the method further comprises the step of calculating a mass change factor, defined as the highest value of the ratio of each base component in the residual mass and the desired mass; and the at least one criterion comprises the lowest value of the mass change factor, 10. Method according to one of Claims 5 to 8, characterised in that the method further comprises the step of calculating a mass change factor, defined as the highest value of the ratio of each base component in the residual mass and the desired mass; and the at least one criterion comprises the lowest value of the product of the mass change factor and a weight of the residual mass. 11, Method according to Claim 10, characterised in that the at least one criterion is used if the warehouse is filled in excess of a predeteimined percentage. 12. Method according to one of Claims 5 to U, characterised in that the at least one criterion comprises the historical re-use of a specific composition. 13. Method according to one of Claims 5 to 12, characterised in that the at least one criterion comprises the shelf life of the residual mass. 14. Method according to Claim 13, characterised in that the shelf life of the at least one residual mass is predicted on the basis of a shelf life model of the base components which are contained in the at least one residual mass. 15. Method according to Claim 13, characterised in that the shelf life of the at least one residual mass is predicted on the basis of a shelf life model of the combination of base components which is contained in the at least one residual mass. 16. Method according to Claim 13, 14 or 15, characterised in that the shelf life of the at least one residual mass is predicted on the basis of a shelf life model of the at least one residual mass in the associated container. 17, Method according to one of Claims 14, 15 or 16, characterised in that the shelf life model is a function of time and ambient temperature. 18. Method according to one of Claims 5 to 18, characterised in that the at least one criterion comprises; that the time that is required for making up the desired mass with re-use of residual masses is shorter than a predetermined value. 19. Method according to one of Claims 5 to 18, characterised in that the at least one criterion comprises: that a certain minimum fraction of the residual mass in an associated container can be re-used. 20. Method according to one of Claims 1 to 19, characterised in that the residual masses, with associated container, are positioned in the warehouse (13) depending on the frequency with which the composition of the residual mass occurs. 21. Method according to one of Claims 1 to 20, characterised in that the method comprises the further step of scraping out the container containing residual mass, the residual mass being collected in a residue container for a specific colourant group. 22. Apparatus for making up a specific quantity of mass of a desired composition from at least one base component with re-use of residual masses which consist of at least one base component, comprising a warehouse (13) for storing containers containing residual mass, a transport device (14) for transporting containers containing residual mass into the apparatus (10) and a metering device (16) for adding base components in order to obtain the specific quantity of mass, the transport device (14) and the metering device (16) being connected to and controlled by a control device (23) which is equipped to carry out the method according to one of Claims 1 to 21 , 23. Apparatus according to Claim 22, characterised in that the apparatus (10) further comprises a combining station (19) for combining residual masses from various containers containing residual mass. 24. Apparatus according to Claim 22 or 23, characterised in that the apparatus (10) further comprises a washing station (21) for containers. 25. Apparatus according to Claim 22, 23 or 24, characterised in that the apparatus (10) further comprises a reception station (11) for containers containing residual mass. 26. Apparatus according to Claim 25, characterised in that the reception station (11) comprises further devices for the identification and characterisation of a container and the residual mass contained therein. 27. Computer-readable medium comprising instructions that can be executed by a computer in order to carry out the method according to one of Claims 1 to 21. 4 ; *Φ*S'.* **

Inventors: VAN LANEN ANTONIUS JOHANNES JO, VAN LANEN, ANTONIUS, JOHANNES, JOSEPHUS
Applicants: LANEN ANTONIUS JOHANNES JOSEPH, UCONTROL B V, UCONTROL B.V., VAN LANEN, ANTONIUS, JOHANNES, JOSEPHUS
Application year: 2001
Main classification: B41F15
IPC codes: B01F13, B41F15, B41F33