Abstract:
Disclosed are a reverse gravure offset printing method and apparatus using a disposable cliche, which do not require cleaning of the cliche and do not require a large quantity of high-definition cliches because the cliche used in reverse gravure offset printing can be discarded after used once or several times and replaced with a new one, thereby achieving cost reduction.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2011-0067433 filed in the Korean Intellectual Property Office on Jul. 7, 2011, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     (a) Field of the Invention 
     The present invention relates to a reverse gravure offset printing method and apparatus, and more particularly, to a reverse gravure offset printing method and apparatus using a disposable cliche, which do not require cleaning of the cliche and do not require a large quantity of high-definition cliches because the cliche used in reverse gravure offset printing can be discarded after used once or several times and replaced with a new one, thereby achieving cost reduction. 
     (b) Description of the Related Art 
     In general, reverse gravure offset printing includes a base  120  applied with conductive ink I, a cliche CL, a roller  110 , and a substrate  140 , as shown in  FIG. 2 . 
     The roller  110  is brought into contact with the base  120  to transfer the conductive ink I from the base  120  to the roller  110 . 
     Afterwards, the roller  110  is brought into contact with the cliche CL to peel off an unnecessary pattern I- 2  on the roller  110  to the cliche CL, and then the roller  110  is brought into contact with the substrate  140  to set a necessary pattern I- 1  on the substrate  140  (see  FIG. 3  and  FIG. 4 ) 
     The cliche L has a plurality of protrusions CL 2 . The protrusions CL 2  are brought into contact with the roller  110  to transfer the unnecessary pattern I- 2  to the protrusions CL 2 , as described above. 
     At this point, the conductive ink I is not transferred to recesses CL 1  between the protrusions CL 2 . As a result, the necessary pattern I- 1  remains on the roller  110 . 
     The roller  110  carries out the above-described process while being rolled and moved by a roller driver  160 . 
     This is well-known and disclosed in detail in Patented Invention No. 975,094, and hence a detailed description thereof will be omitted. 
     Unexplained reference numeral  150  denotes a table supporting the base  120  and the cliche CL. 
     However, the conventional reverse gravure offset printing has the following problems. 
     First, the cliche CL needs constant cleaning. As described above, the roller  110  is brought into contact with the cliche CL to peel off the unnecessary pattern I- 2 , during which the conductive ink, organic substances, alcohol, etc. remaining on the cliche CL have to be cleaned off. 
     However, cleaning of the cliche CL generates a large amount of waste solution, as well as requiring much effort and time. 
     Second, the printing process has to continue even during cleaning of the cliche CL, and hence it is necessary to prepare a large quantity of cliches CL in advance. 
     However, the above-described conventional cliche CL requires high definition and is made of metal, and therefore it costs a lot to prepare a large quantity of cliches CL in advance, as described above. 
     The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in an effort to provide a reverse gravure offset printing method and apparatus using a disposable cliche, which do not require cleaning of the cliche and do not require a large quantity of high-definition cliches because the cliche used in reverse gravure offset printing can be discarded after used once or several times and replaced with a new one, thereby achieving cost reduction. 
     An exemplary embodiment of the present invention provides a reverse gravure offset printing apparatus using a disposable cliche, which peels off an unnecessary pattern on a roller by using a cliche and sets only a necessary pattern on a substrate, the apparatus including a cliche supply device disposed on one side of the reverse gravure offset printing apparatus and supplying the cliche, wherein the cliche supplied by the cliche supply device is used to peel off the unnecessary pattern from the roller and then the cliché is discharged. 
     The cliche supply device may include: an unwinder disposed on one side of the reverse gravure offset printing apparatus and unwinding a web on which the cliche is printed; a rewinder disposed on the opposite side of the unwinder and passing the web through the reverse gravure offset printing apparatus to wind the same; and an imprinting device disposed between the unwinder and the reverse gravure offset printing apparatus and causing the cliche to be printed on the web. 
     The imprinting device may include: a convex-concave roller forming the shape of the cliche by pressing one side of the web; and a pressure roller disposed on the opposite side of the web. 
     The convex-concave roller may be provided with heating means for heating the web. 
     The web may be made of thermoplastic resin. 
     Another embodiment of the present invention provides a reverse gravure offset printing method using a disposable cliche, the method including: the first step of applying conductive ink to a base; the second step of peeling off an unnecessary pattern on the roller by bringing a roller into contact with a cliche supplied by a cliche supply device; and the third step of bringing the roller into contact with a substrate to set a pattern remaining on the roller, wherein the cliche is discharged after peeling off an unnecessary pattern on the roller or after setting a pattern remaining on the roller. 
     According to the present invention explained above, the generation of a large amount of waste solution can be prevented because cleaning of the cliche is not required, and cost reduction can be achieved because there a large quantity of high-definition cliches is not required. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  and  FIG. 2  are conceptual diagrams of a conventional reverse gravure offset printing apparatus. 
         FIG. 3  and  FIG. 4  are conceptual diagrams of a conventional reverse gravure offset printing method. 
         FIG. 5  is a conceptual diagram of a printing apparatus including a cliche supply device in accordance with the present invention. 
         FIG. 6  is a conceptual diagram for explaining an imprinting device in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Before explaining the current examples of the present modular outdoor playpen apparatus in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth in the following description or illustration. 
     The invention is capable of other examples and of being practiced and carried out in various ways. 
     Also, it is to be understood that phraseology and terminology used herein with reference to device or element orientation (such as, for example, terms like “front”, “back”, “up”, “down”, “top”, “bottom”, “left”, “lateral”, and the like) are only used to simplify description of the present invention, and do not alone indicate or imply that the device or element referred to must have a particular orientation. 
     Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. Prior to making the description, the terms or words used in the specification and claims of the present invention are not interpreted using typical or dictionary limited meanings, and are constructed as meanings and concepts conforming to the technical spirit of the present invention based on the principle that the inventors can appropriately define the concepts of the terms to explain the present invention in the best manner. 
     Accordingly, it is to be understood that the detailed description, which will be disclosed along with the accompanying drawings, is intended to describe the exemplary embodiments of the present invention and is not intended to represent all technical ideas of the present invention. Therefore, it should be understood that various equivalents and modifications can exist which can replace the embodiments described in the time of the application. 
     Hereinafter, the present invention will be described in detail with reference to  FIGS. 5 and 6  and an exemplary embodiment. 
     Exemplary Embodiment 
     The present invention involves a reverse gravure offset printing apparatus  100  which peels off an unnecessary pattern on a roller  110  by a cliche CL and sets only a necessary pattern on a substrate  140 . The reverse gravure offset printing apparatus  100  further includes a cliche supply device  200  disposed on one side of the reverse gravure offset printing apparatus  100  and for supplying the cliche CL. 
     By using the cliche CL supplied by the cliche supply device  200 , the unnecessary pattern is peeled off from the roller  110 , and then the cliche CL is discharged. 
     That is, the cliche CL is discharged and discharged after the roller  110  and the cliche CL come into contact with each other a certain number of times, and then a new cliche CL is used. This means using a so-called disposable cliche CL, which is supplied by using the above-described cliche supply device  200 . 
     Conventionally, a cliche made of an expensive metal was used, as described above, and a separate cleaning process was needed. 
     Accordingly, the conventional art has the problem that it takes much time and money because of the cliche cleaning process and a great deal of waste is generated during cleaning of the cliche. 
     In order to solve this problem, the present invention involves manufacturing the cliche to be disposable so that the cliche is discarded after used a certain number of times without the need of a separate cleaning process. 
     Moreover, significant cost reduction can be achieved by using a cheap cliche to be described later. 
     Meanwhile, the cliche supply device  200  may include an unwinder  210  disposed on one side of the reverse gravure offset printing apparatus  100  and unwinding a web W on which the cliche CL is printed, a rewinder  220  disposed on the opposite side of the unwinder  210  and passing the web W through the reverse gravure offset printing apparatus  100  to wind the same, and an imprinting device  230  disposed between the unwinder  210  and the reverse gravure offset printing apparatus  100  and causing the cliche CL to be printed on the web W. 
     That is, the unwinder  210  and the rewinder  220  are disposed in a vertical direction of the reverse gravure offset printing apparatus  100 . 
     At this point, the web W is unwound from the unwinder  210  and wound on the rewinder  220 , extending across the reverse gravure offset printing apparatus  100 . 
     Meanwhile, the imprinting device  230  is disposed between the unwinder  210  and the reverse gravure offset printing apparatus  100 , as described above, so that the cliche CL is printed on the web W. 
     By means of the thus-configured cliche supply device  200  of the present invention, the web W with the cliche CL formed thereon can be constantly supplied to the reverse gravure offset printing apparatus  100 . 
     After using the cliche CL, the cliche CL can be discharged by operating the rewinder  220 , and a new cliche CL can be put into use the rewinder  220 . Consequently, the cliche CL can be used in a disposable manner. 
     As used herein, the term “disposable” is not limited to single use articles but also refers to articles that can be discarded after use. 
     The imprinting device  230  may include a convex-concave roller  231  forming the shape of the cliche CL and a pressure roller  232 . 
     As shown in  FIG. 6 , the convex-concave roller  231  may be disposed on one side of the web W, i.e., on an upper side of the web W, and the pressure roller  232  may be disposed on the opposite side of the web, i.e., on a lower side of the web W. 
     When the web W passes through the convex-concave roller  231  and the pressure roller  232 , a convex-concave portion  231   a  of the convex-concave roller  231  presses the web W to form the cliche CL. 
     The convex-concave roller  231  may be provided with heating means H for heating the web W. 
     As described above, the web W is formed as it passes between the convex-concave roller  231  and the pressure roller  232 , thereby heating the web W and making the formation of the web W easier. 
     For example, the heating means H may be disposed inside the convex-concave roller  231 . 
     Or, other heating means (not shown) may be disposed outside the convex-concave roller  231 . 
     A hot wire or the like may be used in the case that the heating means H is disposed inside the convex-concave roller  231 , or a heating lamp or the like may be used in the case that the other heating means is disposed outside the convex-concave roller  231 . 
     Needless to say, the heating means H may be disposed on the side of the pressure roller  232 . 
     Meanwhile, the web W may be made of thermoplastic resin, thus forming the cliche CL more easily at lower costs. 
     The thermoplastic resin may include PMMA (polymethyl-methacrylate). 
     Besides, the thermoplastic resin may include PC (Polycarbonate), PET (Polyethyleneterephthalate), PEN(Polyethylenernaphthalate, etc. 
     A typical reverse gravure offset printing apparatus other than the above-described is as explained above, so redundant explanation is omitted. 
     In what follows, a printing method S 100  using the above-described reverse gravure offset printing apparatus  100  of the present invention will be explained. 
     First, the first step S 110  of applying conductive ink I to the base  120  is carried out. 
     In the first step S 110 , conductive ink may be applied to the base  120  by spin coating or slit coating. 
     After carrying out the first step S 110 , the roller  110  is brought into contact with the cliche CL fed by the cliche supply device  200  to peel off an unnecessary pattern on the roller  110  is carried out. 
     The second step S 120  may include the twenty-first step S 121  of supplying the web W with the cliche CL formed thereon to the reverse gravure offset printing apparatus  100  and the twenty-second step S 122  of peeling off an unnecessary pattern on the roller  110  by using the cliche CL on the supplied web W. 
     In the twenty-first step S 121 , the cliche CL is formed on the web W, supplied by the unwinder  210 , by means of the imprinting device  230 , and then supplied to the reverse gravure offset printing apparatus  100  by means of the rewinder  220 . 
     That is, the cliche CL is formed on the web W by the imprinting device  230 , and then the web W with the cliche CL formed thereon is fed to the printing apparatus  100 . 
     Afterwards, as explained above, the roller  11  is brought into contact with the cliche CL to peel off an unnecessary pattern on the roller  110 . 
     After carrying out the second step S 120 , the third step S 130  of bringing the roller  110  into contact with the substrate  140  to set a pattern remaining on the roller  110 , i.e., a desired printing pattern, on the substrate  140  is carried out. 
     The fourth step S 140  of discharging the cliche CL may be carried out after an unnecessary pattern on the roller  110  is peeled off in the second step S 120 . 
     This is because the cliche CL is used in a disposable manner in the present invention. 
     Needless to say, the fourth step S 140  of discharging the cliche CL may be carried out after a pattern remaining on the roller  110  is set on the substrate  140  in the third step S 130 . 
     While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 &lt;Description of symbols&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 100: reverse gravure offset printing apparatus 
                 110: roller 
               
               
                   
                 120: base 
                 CL: cliche 
               
               
                   
                 W: web 
                 140: substrate