LINERLESS LABELING SYSTEM

Abstract: A linerless labeling system which utilizes a transparent or opaque paper of plastic film substrate (12). The substrate is provided in web roll (40) form and is printed on one side with an image overcoated with an adhesive. The opposite surface has release characteristics. When applied, the web (10) is fed across an anvil plate (110). A die (165) engages the anvil plate, cuts the label (25) from the web which label is then transfered to the surface of an item such as a plastic container (100).

Description: 2 LINERLESS LABELING SYSTEM 3 The present invention relates to a linerless labeling system and more 4 5 particularly relates to a system for which a substrate such as paper, polyester film 6 or polypropylene film is printed with an image forming a printed web and the web ' is then transferred to an applicator. At the appUcator the pre-printed web is fed g through a die which severs a portion of the web defining the label area and then 9 transfers the label directly to the article. A typical article is a packaging container 10 1 . which may be plastic or other materials. 22 The general field of labeling in which a label is provided without a backing 13 material is generally termed the field of linerless labels. In a linerless label system, " a substrate such as plastic film is repeatedly printed with the label images on one 15 side and coated with an adhesive on the other side. The material is rolled and the 16 labels are severed and applied directly to a surface of a container such as a milk -o container, oil container or the like. Various systems can be found in the prior art 19 in which the printed substrate is coated with adhesive on one side and is provided 20 in roll form eliminating the need for a backing. Reference is made to the article 21 on linerless labels appearing in the August, 1990 Packaging Digest. While various 22 svstems for applying such labels can be found, generally no satisfactory svstem has 23 been provided for the production of a web material having a pressure-sensitive adhesive on the web and which system accurately appiies the labels to a container 26 in a manner which is efficient and inexpensive. 27 1 3 1 2 U. S. Patent No. 4,978.415 discloses an apparatus for applying labels to 3 articles. The labels are cut from a web which has an adhesive applied to one side. 4 - The machine includes cutting rollers which cut through the ac hesive side of the 6 web in order to sever the labels. The cuπing edges of the rollers are kept clean ' by application of a liquid silicon or similar release composition. U. S. Patent No. 4,522,370 (reissued as RE 32,249) discloses a linerless, 9 double-coated pressure adhesive tape which is mounted directly upon itself in a roll 10 so that it can be later unwound. The patent is directed to a composition of the 12 pressure-sensitive adhesive which is a cross-link alkyl acrylate polymer. 13 U. S. Patent No. 4,842.902 discloses a method for preparing an improved, 14 peelable protective backing for pressure sensitive adhesives (PSA), particularly 15 those which are described in the patent as solvent cast curable silicon pressure- 16 sensitive adhesives. The invention involves applying certain curable fluorosilicon 17 - „ compositions to a substrate and curing the applied composition before it is brought 19 into contact with the PSA. 20 U. S. Patent No. 4,716,052 relates to a method of making a pressure- 21 sensitive adhesive stock material which eliminates the need for self-supporting 22 paper, cardboard or plastic substrate. A layer of pressure-sensitive adhesive is 23 provided on a release liner. 24 n e U. S. Patent No. 4,784,714 discloses a linerless thermal label printer and 26 applicator. The cutter is provided to separate the linerless thermal sensitive paper 27 2 1 into individual labels. A vacuum system transports the separated labels from a cutting station to an adhesive station and thereafter to a label ejection station. At 5 the adhesive station, adhesive is activated and a vacuum blower system at the label 6 ejection station causes the separated label to be transfened to the item. ' In accordance with the present invention, a linerless labeling system is o provided which utilizes a suitable substrate which may be paper or a synthetic film 9 such as polyester, polypropylene or a similar printable flexible material. The 11 substrate is provided in strip form and is printed on one side with a suitable image 12 in any desired shape and colors. Preferably the substrate is transparent and the 13 printed label image is applied to the surface of the label which will subsequently " be applied or placed in contact with the article. Registration marks, which may be 15 printed indicia, notches or holes, are applied at predetermined locations along the 16 substrate to facilitate automatic registration during application. An adhesive is - Q applied over the printed image by spraying, by rolling or by other conventional 19 techniques and may be heat or water activated. The opposite side has release 20 properties or is coated with a release agent The completed web is wound into a 21 roll and provided to the user in roll form. 22 If the substrate is opaque, as in the case of paper, the release coating is 23 applied over the printed image and the adhesive is applied to the opposite surface. 24 25 Registration indicia are provided at regular intervals. 26 27 3 28 1 2 The applicator equipment for applying the labels includes a unwind shaft 3 . on which the roil is mounted. Tbe web is fed across an anvil plate which defines 5 an aperture which receives a reciprocable transfer member. The transfer member 6 has a recess which contains a soft, porous material such as a sponge. The transfer- ' member is operatively connected to a plunger or actuator and the interior of the 8 member communicates to a low vacuum source. An oppositely disposed 9 cooperating clamp plate receives an interchangeable steel rule die which cooperates -, . with the anvil plate to sever the label when the two are brought into engagement 12 The web is pre-marked with locator or registration marks which are sensed 13 as by an optical reader or other sensor. The applicator unit is positioned adjacent a conveyor line along which the articles to be labeled move. A typical application 15 would be the labeling of plastic milk bottles. A microswitch or other sensor senses 16 the presence of an article aligned with the applicator unit The optical reader or o other sensor senses the registration markings and causes the damping plate and 19 to retract bringing the die against the substrate and anvil plate at the proper 0 location. The die cuts the label from the web and the transfer member extends to 1 transport the removed label, which is held in place by the vacuum, to the 2 appropriate surface location on the packaging or container. The adhesive on the 3 label surface adiacent the article secures the label to the article and the vacuum 24 J 5 is released allowing the transfer to return to a retracted position so the next 6 printed label on the web may be advanced. Since, the printed image is on the 7 4 8 1 2 surface of the web adjacent the container, it is protected from moisture or 3 chemicals or other damaging environmental elements which may be present The 4 die being a steel rule die is of simple construction and may be easily changed in 6 accordance with the label configuration. ' In accordance with the foregoing, a principal object of the present invention g is to provide a linerless label system which eliminates the requirement for 9 expensive paper release liners such as those coated with silicone. 10 Another object is to provide labels pre-printed web roil form which labels 22 are adhesively coated, printed and provided with a release coating to facilitate easy 13 unwind, removal and application. 14 Another object of the present invention is to provide a roll of linerless labels 15 which eliminates the need for a backing thereby substantially increasing the 16 number of labels available on a single roll of labels. 17 -. „ Another object of the present invention is to provide a linerless label which 9 is fabricated from a substrate of paper or a this plastic such as polyester, 20 polypropylene or polyethylene film forming a label which is environmentally stable 21 and resistant to water, humidity and many chemicals. 22 Another object of the present invention is to provide an applicator including 23 a die which cuts and removes the labels from an adhesive coated web and uhich 24 95 has means for transferring the severed labels directly to the article to be labeled. 26 27 5 28 1 2 The above objects and advantages along with a more complete 3 understanding of the present invention will be had from the foUowing description 4 s and claims, taken in conjunction with the accompanying drawings in which: 6 Figure 1 is a top side view of a portion of a web of printed linerless labels / in accordance with the present invention; g Figure 2 is a back side view of a portion of a web provided with printed 9 labels in accordance with the present invention; 10 Figure 3 is a schematic representative showing the preparation of the web 2 and roll of linerless labels; 13 Figure 4 is an enlarged cross-sectional view of a portion of the web; 1 Figure 5 is a block diagrammatic representation of the steps in applying a linerless label to an article; 16 Figure 6 is a perspective view of the applicator machine; ι ς Figures 7 to TE illustrate the sequence of operations carried out by the 19 applicator in severing and applying a label to an article; 20 Figure 8 is a detail view of the label transfer member, and 2 Figure 9 is a view takes along line 9-9 of Figure 7. 22 For purposes of consistency throughout this specification, the term 23 "substrate" is used herein to describe the paper or plastic base material to which 24 ft, the printing and adhesives and coatings are applied. Tbe term "web material" or 26 "web" will be used to describe the substrate material which bas been printed, 27 28 1 2 coated with an adhesive, and a release agent The web material is provided in roll 3 form for application. The invention described herein is applicable to the labeling 4 _ of articles including packaging containers such as cans, bottles and boxes which g may be paper, metal or plastic. It will be appreciated that the invention also has 7 application to a wide variety of packaging containers but for purposes of 8 description, reference will be made to labeling containers such as plastic milk 9 bottles and similar liquid containers which are intended to be exemplary of use of 10 the system. 11 y The first principal component of the system is the rolled web containing a 13 plurality of pre-printed linerless labels and the second aspect of the invention is the 14 application of these labels to an article. 1 5 Turning first to the preparation of labels in rolled web form, Figures 1, 2 16 and 4 show a section of the web 10 which is provided to the label applicator in roll 17 form as will be explained in detail hereafter. The web 10 is used in an applicator 2 Q unit 14 in pre-printed roU foπn and has a suitable substrate 12 which may be paper 20 or plastic film. Although paper may be used, preferably the substrate 12 is a thin 21 plastic film, such as 1 mil polyester, polypropylene or polyethylene and is 22 transparent or translucent The substrate 12 is shown as being a strip having 23 opposite longitudinal edges 16 and 18, top and back surfaces 20 and 22, 24 respectively. The term "back" surface is used with reference to the surface of tbe og substrate that it will be applied to the packaging article and the term "top" refers 7 7 28 1 2 to the outer suπace which is exposed when the label is in place. The back surface 3 22 of the substrate is printed with a repetitive image defining the label pattern 25, 4 - 25A, 25B, etc. The label sets forth the pertinent information and may be 6 arranged in any convenient shape, rectangular being shown. As indicated, the label 7 information is printed on the back surface 22 of the substrate and may be overprinted with opaque coating 26 in the event the item to which the label is to 9 be applied is transparent Since the label 25 appears on the back surface of the 10 substrate, the printing is protected from exposure to the environment, moisture and 22 wear and tear by the substrate itself once applied to an article. 13 Registration indicia 30 are provided at spaced-apart locations along the 14 substrate preferably at an edge. The registration indicia 30 may be imprinted so 15 they may be optically read so as to properly register the label in the applicator unit 16 14. The registration indicia may also be in the form of notches or cut-outs at 17 spaced- apart locations in the substrate which may be optically or mechanically 18 9 sensed to properly index and register the completed web in the aj, Hcator 14. 20 Once the substrate is printed and provided with the registration indicia 30, 21 an adhesive coating 32 is applied to the back surface over the lab ' pattern and, 22 if needed, suitable release coating 34 is applied on the top side. Th *. printed, 23 adhesive and release coated substrate is then wound into a web roll 40 rt. dy to be 24 „ provided to the user. 26 27 8 1 2 If the substrate is opaque, as in the case of paper, the printed label image 3 25 is applied to the top, rather than the back surface 22 so as to be readable when 4 - applied. 6 Figure 3 schematically depicts the preparation of the web roll 40. The 7 substrate 12 which is preferably a thin, elongate strip of material as described and Q is provided as roll stock 44. The desired repetitive images 25 are applied to 9 surface 22 at printing station 50. The printing can be accomplished by any 10 convenient printing technique such as conventional fiexographic techniques. The 22 printing may be multi-color and an opaque overcoating 26 may be applied at 13 station 52, if desired. The top surface 20 of tbe substrate is coated with a release 14 coating at station 54. The composition of the release coating used may vary with 5 the composition of the substrate but typicaUy the release coating will be a silicon 16 which may be applied by a spray applicator. Some materials such as polypropylene 17 Q exhibit inherent release characteristics and additional application of a release lα 2g coating may not be necessary. 20 Other methods of applying a release coating may also be used which 2 generally involve passing the substrate over a roUer 62 to which is applied the 22 silicon. The silicon is transferred to the substrate and appropriate wiping blade 60 23 cooperates with the roller to control the amount of release agent applied to the „_ substrate. In some cases, the substrate may be dried by fans, heat or application 26 o radiant energy such as UV. 27 23 1 2 The back surface 22 of the substrate is provided with index or registration 3 marks 30 at station 56 which are applied at an edge and outside the label image area. The substrate is coated with a suitable adhesive at station 58. The type of 6 adhesive will vary with the characteristics of the substrate. For example with a ' polyester substrate, adhesives such as rubber based acrylics have been found to be g suitable. The adhesive can be apphed by spraying or- may be applied by an 9 application roUer 66 which rotates through a bath of adhesive and thereafter 10 contacts the surface of the substrate. Other adhesives may be used and are weU 22 known to those skilled in the art Adhesives which are water or heat activated may 13 be used and activated at the time of application. 14 Suitable doctor or wiping blades 70 may be provided for removing excess 15 adhesive from the substrate. Thereafter, the adhesive may be suitably dried by 16 application of heat or other forms of energy such as RF energy at station 72. - „ The registration or indexing indicia 30 are applied at predetermined spaced- 19 apart intervals located to register the labels with the applicator machine 14 duπng 20 the application process. The registration marks may be printed on the substrate or may be in the foπn of apertures or notches provided along an edge of the 22 substrate. The substrate is then wound into a roll web 40 ready for the applicator 23 14 and is provided to the labeler in this foπn. 24 9 The applicator unit 14 is best shown in Figures 6, 7, 8 and 9. The sequence 26 of labeling operations is shown in Figures 5 and 7A to 7E. The applicator unit 14 27 10 23 1 2 includes a frame which has opposite side walls 82 and 84. Unwind shaft 86 extends 3 transversely between the side walls and is supported at opposite ends at bearing plates 88. The roU web 40 of label stock is mounted on shaft 86. Tbe individual 6 labels 25, 25A, 25B, etc. are die cut from the web as it is fed from the roll and ' applied to the containers. The containers to which labels will be applied are o indicated by the numeral 100 and are shown as polyethylene milk containers as for 9 example the type normally containing one-half gaϋon of milk. The containers are 0 advanced to the application station adjacent the applicator machine 14 by a conveyor 90 on which is located a sensor 96 shown as a microswitch. Sensor 96 identifies the presence of a container and actuates the applicator when the container 100 is properly located on the conveyor with respect to the applicator unit 14. After labeling, labeled containers are advanced and a new container to 6 be labeled is moved into position adjacent the applicator. The web 10 extends over a feed roller 104 and between first and second pairs of guide rollers 72 and 74 extending transversely between the side walls of the 0 applicator and aligned with the anvil plate 110. A conventional unwind unit not 1 shown, serves to draw the web 10 from the roll 40 in the path described above. Suitable tensioning devices to maintain proper tension on the feed stock may be incorporated and description is not necessary to an understanding of the invention 4 as these devices are well known in the art 6 Anvil plate 110 is mounted on a support plate 112 which support plate extends verticaUy transversely between the side walls of the unit. Anvil plate 110 defines aπ opening 115 which receives the transfer member 120. Preferably the lateral dimension of the opening 115 in the anvil plate is less than the size of the label so that tbe severed label may be suppoπed on the transfer member during the apphcation operation. The cutting of the label is accomplished by a die 165. Die 165 is shown as a steel rule die which has aπ exterior cutting edge 168 which is configured in the desired shape of the label to be applied to the container. The die may be any suitable material such as tool grade steel and is detachably secured by screws 160 at the inner side of clamping plate 150. The die defines a cavity 166 extending rearwardly from the cutting edge 122. Clamping plate 150 is verticaUy disposed at a location spaced apart from anvil plate 110. Tbe clamping plate is shown as a rectangular steel block having a central opening or aperture 152 which is larger than the opening in the die. Threaded bores 156 extend through the plate adjacent the aperture and receive machine screws 160. The die 165 is detachably securable at the inner side of the clamping plate by threaded bores which receive the ends of screw 160. The opening in the die is aligned with the opemng 115 in the plate. It wiU be apparent that the die 165 may be changed by simply removing the machine screws 160 and replacing the die 165 with another die having the desired cutting shape. 1 2 The clamping plate is suppoπed on a pair of cylinder rods 170, each 3 operably connected to a pneumatic or hydraulic cylinder 172 which by means of 4 5 rods 170 move the clamping plate toward and away from the anvil plate 110. An 6 optical sensor 180 is located above the plate and initiates the application sequence 7 once the microswitch 96 has energized tbe application machine. g The transfer member 120 is extendible from the anvil plate and has a 9 housing 122 defining an outwardly opening cavity 125. The housing 122 is 10 selectively extendible and retractable by means of rod 126 of actuator 128. The 22 cavity 125 is dimensioned so as to be smaUer than the label to be applied. The 13 cavity contains a sponge or other porous material 132 and is connectable to a low 14 vacuum source via conduit 134 across vaive 136 so that a low vacuum may be 15 applied to the cavity and released as required to transport and deposit the severed 16 label. 17 - « The electrical controls and the pneumatic or hydraulic systems are weU 19 known in this particular aπ and detailed description of these is not deemed 20 necessaiy. Similarly, the control system may also include devices to regulate the 21 ** tension of the web as it is unwound and such tensioning devices generally 22 pneumatic in nature are also weU known. 23 The invention wiU be better understood from the foUowing description of 24 25 operation. 26 7 13 28 1 2 Once the applicator unit 14 is properly positioned adjacent the conveyor 90 3 on which articles to be labeled are placed, the unit operates as foUows. The presence of an article 100 to be labeled is sensed by microswitch 96 which switch 6 will serve to actuate the applicator machine. The position of an article ready tb ' receive a label is as shown in Figure 7A as the article is aligned with the male and g female dies. The applicator has been suitably loaded with a web roll 40 pre- 9 printed and coated with a release and adhesive as has been described which will 10 1 1 be unroUed to dispense a continuous web 10. When the applicator 14 is actuated, 12 the optical sensor 180 wiU properiy advance the web 10 so that a selected label 25 13 is properly positioned with respect to the anvil plate and die as seen in Figure 7 A. 14 Once registration is proper, actuators 170 will cause the clamping plate 150 to 15 retract bringing the die 165 into engagement with the web. In this position, the 16 web stock is interposed between the die 165 and the anvil plate 110 as seen in j o Figure 7B, severing the label in the shape determined by edge 168. The transport 19 member 120 is actuated in the sequence and moves forward under the influence 20 of the cylmder 128 and simultaneously a low vacuum is applied via conduit 134 to 21 cavity 150 in the die as seen in Figure 7C. The transport member removes the 22 severed label from the web and continues to move outwardly as seen in Figure 7D. 23 The member 120 continues to move until the transported label contacts a surface 25 of the container. At this point the adhesive coating on the back surface of the 26 removed label 25 wiU adhere to the surface of the container. The vacuum in cavity 27 14 28 130 is released and the member 120 retracts and the clamping plate and die move outwardly away from the anvil plate to permit the web to advance a predetermined distance as estabUshed by the registration indicia as iUustrated in Figure 7E. The container 100 with the appUed label is advanced on the conveyor and a new container is moved into position actuating switch 96 to initiate repetition of the operation. Thus, it will be seen from the foregoing that the present invention provides a substantial number of advantages. The linerless label eliminates the need for expensive silicon coated paper release liners, printed paper stocks and plastic film laminates which are conventionaUy required to make durable labels. With the present invention, a single web is provided which is adhesive coated, pre-printed and provided with release lining so that it wiU be suppUed to the user in roU form for easy unwinding. The applicator of the present invention aUows the use of thinner labels which makes recycling of the containers to which the labels are suppUed more feasible. The linerless labels of the present invention also permit the number of labels per roll to be increased, for example five to six times, requiring less storage space and providing a more efficient operation as the re-loading time on the applicator is reduced. 1 2 The linerless labels as mdicated can be made from various materials, 3 preferably plastic films, including the newer plastic films which may be more 4 environmentaUy safe and biodegradable. Also, the printing of the linerless labels 6 on the back of the label protects the labels from exposure to water, humidity and ' other chemicals. g Waste disposal is reduced, both at the manufacturing level and during 9 appUcation resulting from the fact that much less bulk is used. 0 The steel rule dies are easily interchangeable and may be used to cut labels 2 of almost any shape from the adhesive coated web. 3 The simple label feed dispenser for the single film labels is efficient 4 effective and simple. 5 It will be obvious to those skilled in the aπ to make various changes, 6 alterations and modifications to the system described herein. To the extent those 7 R various alterations, modifications and changes do not depart from the spirit and 9 scope of the appended claims, they are intended to be encompassed therein. 0 I CLAIM: 1 2 3 4 5 6 7 16 8

Claims: 1 claim 1. The method of labeling an article 2 comprising: (a) providing a roll of a flexible substrate having 3 opposite surfaces and having pre-printed images at 4 predetermined intervals along the substrate, said substrate being at least partially coated on one surface with an adhesive; 6 (b) feeding the substrate from the roll to an 7 application station at a predetermined feed rate; g (c) positioning the article to be labeled adjacent the application station; 9 (d) providing an interchangeable die at the 10 application station having a predetermined shape in H the desired shape of the label to be applied to the article and which has an opening extending through the 12 die; 13 (e) bringing the die into contact with the stibstrate }4 generally normal to the substrate against an oppositely positioned generally planar anvil plate by 15 moving said die toward said anvil plate to sever a 16 label of predetermined shape from said substrate; 17 (f) bringing a transfer member into contact with the severed label and applying and maintaining a 18 predetermined vacuum on the transfer member to retain 19 the severed label thereon; 20 (g) extending the transfer member through openings in the die and anvil to bring the severed label into 21 contact with the article with the adhesive surface of 22 the label against the article; and 23 (h) thereafter releasing the vacuum and withdrawing the transfer member leaving the label affixed to the 24 article. 25 Claim 2. The method of Claim 1 wherein said substrate 26 has printing applied to one surface and adhesive 27 17 28 1 applied over the said printing and a release agent applied to the opposite surface of the substrate. Claim 3. The method of Claim l wherein said 3 substrate is provided with spaced-apart registration 4 marks and further including the step of sensing the . registration marks to advance and position said substrate with respect to said die cutter at a 6 predetermined rate. 7 Claim 4. The method of Claim 1 wherein said substrate β comprises a think, flexible plastic film. Claim 5. The method of Claim 1 wherein said substrate o 9 is paper which has printing and a release coating on 10 one surface and an adhesive on the opposite surface. 11 Claim 6. The method of Claim 1 wherein said adhesive is heat activated at the time of application. 12 Claim 7. The method of Claim 1 wherein said adhesive 13 is water activated at the time of application. H Claim 8. An applicator apparatus for applying labels to articles which labels are provided on a web which 15 is moved sequentially past an application station 16 comprising: 17 (a) feeding means for feeding a web having opposite surfaces and having labels repetitively printed on a 18 surface thereof and having an adhesive on the other 19 surface thereof, said web being provided with 20 registration indicia; (c) a die having a cutting edge of a predetermined 21 shape and defining an opening therethrough, said die 22 being interchangeably mounted on a clamping plate; 23 (c) an anvil plate having a generally planar surface positioned adjacent said die and defining an opening 24 receiving a retractable and an extendable transfer 25 member aligned with said opening; 26 18 27 28 1 (d) means for selectively moving said die toward said anvil plate into contact generally normal to the web to sever a selected label from said web; 3 (e) means for selectively applying a vacuum to said transfer member; _ (f) sensing means for advancing said web at an o intermittent predetermined rate whereby a label is ® severed by said die and the label transferred to the 7 surface of an article by extending said transfer * member through said die and said opening in said anvil; and ' (g) means for releasing said vacuum when said label 0 s applied to the article. 1 Claim 9. The apparatus of Claim 8 wherein said transfer member defines a vacuum cavity including a 2 porous material therein. 3 Claim 10. The apparatus of Claim 8 wherein said articles are delivered to the application apparatus by a conveyor and further including means for sensing the 5 presence of an article at said application apparatus 6 and means responsive to said sensor to activate said j application apparatus. Claim 11. The apparatus of Claim 8 wherein said 8 control means comprises an optical sensor positioned 9 to read said registration indicia. 0 1 2 3 4 5 6 7 19 8

Inventors: BRADSHAW FRANKLIN C, BRADSHAW, FRANKLIN, C.
Applicants: BOSS SYSTEMS L L C, BOSS SYSTEMS, L.L.C.
Application year: 1995
Main classification: B32B31
IPC codes: B65C9