| Walmark Corporation phone: (847)546-0400 fax: (847)546-1777 |
| 1. Labels Curling Away From Bottles. | |
| Possible Problem | Suggested Solution |
| a. Applications of too much glue. | Apply the thinnest possible even film by adjusting the scraper close to the glue roller. |
| b. Inefficient wiper action or rolling compression. | Adjust wipers or compression so that proper pressure is applied slightly beyond all edges of the labels. |
| c. Use of stiff, springy labels that are vertically grained. | Ruffle or flex the labels without folding or creasing before running them by bending label stacks sharply in the direction of the application. (make sure, however, that they lie flat in the label hopper of the machine.) |
| d. Use of glue with insufficient tack. | Apply a highly concentrated glue in a very thin film. Ask glue supplier for a suitable grade of tackier glue. |
| e. Labeling wet bottles. | Humidify or stipple the labels. Change to a jelly type labeling gum. Install an air blower on the conveyor line leading to the labeling machine to blow off excess water. |
| 2. Wrinkling or Blistering of Labels. | |
| Possible Problem | Suggested Solution |
| a. Use of a glass package having a two-directional spherical curve of the labeling surface. | Design labels to conform as snugly as possible to the contour of the labeling surface. Humidify or stipple automatically applied labels or prolong the tempering time of hand applied labels. Wherever possible design the package so that the labeling surface curves in only one direction. |
| b. Application of too much glue. | Apply the thinnest possible film of glue by adjusting the scraper close to the glue roller. |
| c. Use of vertically grained labels. | Humidify or stipple the labels before gluing. Specify horizontal graining on future label orders. |
| d. Uneven absorbency of label paper due to spotty sizings or offset inks and varnish coatings. | Humidify labels before gluing. Use a slow drying labeling glue to provide time for uniform penetration of the stock. |
| e. Too much moisture in machine labeling glue. | Use a labeling adhesive with high solids. Run as concentrated as possible. |
| f. Use fast drying glue on labels of high moisture sensitivity. | Use a tacky but slow drying glue to permit shrinkage of the labels as moisture evaporates. If labels have been stored in a warm, dry location and have consequently dried out, they should be humidified before running. |
| g. Apply glue to all but a small portion of the label. | Use picker pads or center gummer pads of the proper size for the labels being applied by machines operating on the stencil principle. |
| h. Inefficient wiper or compression action. | Adjust wipers, pressure pads, or compression belts to apply proper and even pressure throughout the label area. |
| i. Bottles wet when labeled. | Humidify labels. Change to a jelly-type labeling gum. Install an air-blower on the conveyor line leading to the labeling machine to blow off excess water. |
| j. Glue on grip-finger of machine. | Wash grip-finger thoroughly and dry. |
| k. Labeling plastic bottles that have been filled with a very hot or cold liquid. | Humidify the labels. Use an easier-spreading adhesive. An overall adhesive pattern on the labels may help. |
| 3. Failure to Pick Labels Out of Hopper. | |
| Possible Problem | Suggested Solution |
| a. Pickers, pads, or bottles not properly contacting labels. | Check to see that the label follower is riding freely and the follower plate is covering the entire label area. Adjust pickers to the same plane or level. Keep the label hopper prongs clean ands smooth. |
| b. Application of Inadequate or excessive glue to the pickers, pads, labels, or bottles. | Adjust scraper to apply thin, even glue film. |
| c. Glue lacking sufficient initial tack to pick labels out of hopper. | Run concentrated film in a minimum even film. |
| d. Prongs or hooks of label gripping labels too tightly. | Check adjustment of prongs so that the stack rides freely. Mash dried glue from prongs and hooks. If prong hooks are rough, slant them and smooth with fine emery cloth. |
| e. Insufficient supply of labels in the label hopper. | Maintain a cushion of labels in the hopper to ensure a proper spring tension on the follower plate. |
| f. Adhesive drying to rapidly. | Obtain slower drying glue. | 4. Spotty Adhesion. |
| Possible Problem | Suggested Solution |
| a. Pickers not on same level, or bent. | Level the pickers to the plane and straighten out any surface irregularities. |
| b. Transfer roller and glue roller not in proper contact. | Adjust the glue roller to transfer roller to provide a flush meeting. |
| c. Uneven transfer of labeling glue. | If the glue is too viscous to transfer evenly, dilute with a thin mixture of the same glue. Adjust the scraper to provide a uniform clearance of the glue roller. Adjust transfer roller to apply glues evenly to the pickers. |
| d. Use of labels having uneven absorption qualities. | Use a high solids type labeling gum or a fast-tacking, slow-drying glue. Humidify the labels Switch to a uniformly absorbent label stock. |
| e. Water not thoroughly incorporated into the glue. | Water should be added slowly and mixed into glue thoroughly before placing into the glue pot. When diluting glue already in the pot of the machine, use a thin mixture and stir in well. |
| f. Glue partially dry on label or container before label is applied. | Apply labels to the bottles promptly after gluing. If glue is too viscous, particularly on labels that pump and recirculate the adhesive, dilute it with a thin mixture of the same glue. Adjust scrapers and transfer rolls to apply uniform film of adhesive. |
| g. Use of the wrong type of glue for the type of surface being labeled. | If labeling surface is treated, greasy, opal, or stippled bottles, or treated polyethylene and PVC containers, consult your adhesive supplier for suitable glue. |
| 5. Tearing of Labels in the machine. | |
| Possible Problem | Suggested Solution |
| a. Glue accumulating and setting on the transfer rollers, pickers, prongs, wipers, among other parts. | Wash all gluing parts with warm water. Dilute the glue as described by the supplier. Keep the machine in steady operation or clean all gluing parts if labeling is interrupted. Use slower drying adhesive. If labeling untreated plastic bottles with resin emulsion adhesives, the transfer roller may have to be mechanically driven. |
| b. One or both pickers or pad not receiving adequate glue film. | Be sure pickers are on the same level so that both will receive identical glue films. |
| c. Faulty adjustment of label hopper unit. | Adjust prongs so the label stack rides freely. See that there is sufficient spring tension on the label follower and that the follower plate presses labels evenly but not too tightly against prong hooks. Smooth label prong hooks with fine emery cloth and adjust evenly. |
| d. Wipers engaging labels. | Clean with warm water to remove accumulated and hardened glue. |
| e. Thin soft paper with low tear resistance. | Use adhesive at thinner consistency to get more slip on picker plates. |
| 6. Labels Falling Off Bottles. | |
| Possible Problem | Suggested Solution |
| a. Applications of too much glue. | Adjust the scrapers so that a thin film is applied. Test a label glue that dries to a more continuous film. |
| b. Use of wrong type of glue for the surface being labeled. | If labeling surface is treated, greasy, opal, or tippled bottles, or treated polyethylene or PVC containers, consult your adhesive supplier for a suitable glue. Alkaline jelly gums generally exhibit better adhesion than dextrin or casein types. |
| c. Use of hard-sized, resistant paper stock. | Use a tack, slow-drying label glue. Change to a softer, more absorbent label stock. |
| d. Remoistening of label glue on bottles stored in a damp location. | Use a non-hygroscopic (moisture-resistant) labeling glue. |
| e. Glue partially dry on label or container before label is applied as often experienced in delayed table gumming operations. | Apply labels to bottles promptly after gluing. Use slower-drying adhesive. Use a damp cloth when hand labeling. |
| f. Inadequate glue application (rare). | See that scrapers are properly adjusted. |
| g. Containers very cold or hot at time of labeling. | Use jelly type glue. |
| h. Untreated or poorly treated plastic containers. | Plastic containers should be adequately treated and tested prior to labeling for adequacy of treatment. also, see "b" above. |
| 7. Discoloration or Staining of Labels. | |
| Possible Problem | Suggested Solution |
| a. Use of label stock colored with water-sensitive or alkali sensitive dyes. | If plain water causes discoloration, consult the label supplier. "b". If color does not change with plain water, but does with the type of glue you are using, test a chemically neutral grade. |
| b. Use of thin translucent labels. | Test a light colored or transparent labeling glue. Change to a heavier, more opaque label stock. |
| c. Use of highly absorbent labels. | Test a cohesive labeling gum that does not penetrate excessively. Change to a moderately hard sized and calendar stock. |
| d. Oil or grease on bottles in filling or capping machines. | Clean fillers and cappers and make necessary repairs or adjustments to prevent a recurrence. |
| e. Glue contaminated by foreign matter. | Use only clean utensils. Clean and refill glue pot regularly. (see "14-Molding of Labeled Bottles.") |
| f. Hygroscopic (moisture-absorbant) glue. | Switch to a non-hygroscopic glue. |
| g. Application of too much glue. | Clean wipers, brushes, and pressure pads. Tighten the scraper close to the glue roll. |
| h. Storage of labeled containers under excessively damp conditions. | Use a moisture-resistant adhesive. |
| 8. Smearing of Bottles Labels. | |
| Possible Problem | Suggested Solution |
| a. Application of too much glue. | Tighten the scrapers close to the glue roll. |
| b. Excessive pressure of flap type wipers. | Decrease the pressure slightly to make sure that enough pressure is exerted to prevent labels from curling away after application. |
| c. Use of glue that dries to a cloudy film. | Test adhesive that dry to a clean film. |
| d. Slipping of labels. | See "9-misaligned Labeling" |
| e. Use of freshly printed labels. | Age labels until inks are perfectly dry. |
| f. Poor quality ink used in printing labels. | If ink smears on labels with normal handling, consult label supplier. |
| g. Tendency of adhesive to build up an on pressure pad. | Put damp cloth over face of pad. |
| 9. Misaligned Labeling | |
| Possible Problem | Suggested Solution |
| a. Uneven application of glue to labels. | True the scraper or the feed-and transfer rollers to secure a uniform glue film. Check to see that pickers are level. Smooth out any hollow spots on the face of pickers. User pickers of proper size for labels being run. |
| b. Excessive glue application. | Tighten the scraper close to the glue roll. |
| c. Grip-finger not holding labels firmly. | Adjust grip-finger leveler to exert just enough pressure to prevent wipers from shifting position of labels on the bottles. |
| d. Uneven pressure of flap type wipers. | Check wiper action to be sure of equalization of pressure at both ends of label. |
| e. Rough or gummed up prongs on label holder. | Clean label holder prongs with damp cloth and smooth gripper hooks with fine emery cloth. |
| f. Improper registration of labels. | Align label holder to bring it in proper position and if more than one, in proper relation to each other. Square off bottle-rest mechanism. |
| g. Use of glue with inadequate tack. | Run the glue as concentrated as possible. Test glue with higher initial tack. |
| h. Bottle-rest permits shifting of containers. | Get a better designed bottle-rest. |
| i. Pressure pad not hitting bottle squarely. | Correct adjustment. | 10. Scuffing of Labels When Nesting. |
| Possible Problem | Suggested Solution |
| a. Applications of too much glue. | Dilute the glue to the extent prescribed by the manufacturer and apply the thinnest even film you can regulate by closer scraper adjustment. |
| b. Use of slow-setting glue. | Usually the setting speed of the glue can be increased by running at a higher concentration and applying sparingly. But if this fails, consult your adhesive supplier regarding faster-setting grades. |
| c. Freshly labeled bottles being scraped while nesting. | Check to see that the dimensions of the bottle nest are correct for the size of the bottle. If nesting by hand, slide bottles into compartments so that labeled area does not contact partitions, or lower the case so that the bottles can be dropped straight into the nest. If nesting by machine, use proper grid, funnel, and guiding fingers for size of container being packed. Clean and adjust guiding fingers of boxing unit to prevent their engaging the labels. Replace broken guiding fingers. |
| d. Faulty wiper action | Adjust wipers to apply proper pressure slightly beyond all edges of the labels. |
| e. Wrinkling or blistering of labels. | See "2-Wrinkling or Blistering of Labels". | 11. Loss of Labels in Water Coolers. |
| Possible Problem | Suggested Solution |
| a. Temperature of water in the cooler. | Add ice more frequently or adjust the refrigerating unit to maintain a lower temperature. Drain water coolers, if left unattended. Clean the cooling unit frequently and remove labels which have soaked off bottles. |
| b. Use of a water-absorbent label stock. | The face of bottle labels subject to liquid refrigeration should be rendered water-resistant by sizing solid ink, backgrounds or varnish coatings, for example, foil-laminated labels are highly water repellent. |
| c. Use of stippled or other decoratively molded bottles. | For best results, use a bottle with smooth labeling surface. |
| d. Use of readily water-soluble adhesive. | Switch to a cold-water-resistant labeling glue. |
| e. Application of too much glue. | To ensure a close contact between the label and the bottle, regulate a very thin, even glue application. |
| f. Inadequate glue area on labels. | Increase glue area of labels by adjusting or substituting boarder faced pickers. |
| 12. Difficulty in Removing Labels. | |
| Possible Problem | Suggested Solution |
| a. Faulty soaker action. | Have soaker inspected and overhauled. See that sufficiently high water temperature and caustic concentration is maintained. |
| b. Use of a warm-water-resistant glue. | Change to a more heat-sensitive glue. |
| c. Use of highly water-repellent label. | Test other cleaning compounds. Consider the possibility of substituting a less resistant type of label stock. Bear in mind the greater importance of retaining labels in the field than of simplifying their removal in the plant. |
| d. Applying glue to an excessive label area. | Reduce glue area on labels by adjusting the pickers or by substituting pickers with a narrower gluing surface. Make sure to avoid
extremes which would sacrifice field efficiency. NOTE: In some instances a wetting agent may assist in removing labels. |
| 13. Foaming in the Soaker. | |
| Possible Problem | Suggested Solution |
| a. Formation of soaps from reaction of bottle cleaning solution with (A) contamination on bottles, or (B) sizing, printing, and finishing of labels. | Provide an efficient pre-rinse. Dump label basket or screen frequently. Change the soaker solution more often. Test other cleaning agents. Test lower caustic concentrations and water temperatures. Test other types of labels. |
| b. Application of too much glue to labels. | Tighten scraper of bottle labeling machine. |
| c. Mechanical reasons such as excessive pressure of circulation pump leaks on intake side of pump, or insufficient tank height to provide room for blanket of foam. | Consult soaker manufacturer regarding practical correctives. |
| d. Use of soft water. | There is no direct corrective for this, as artificial means of hardening seldom prove successful. |
| e. Solution level in tank below intake level. | Fill tank to proper level and adjust caustic to compensate. |
| 14. Molding of Label Bottles. | |
| Possible Problem | Suggested Solution |
| a. Spillage of bottle contents at filling machine. | Repair filling machine to ensure it's proper functioning. Investigate causes of forced stops at filler. |
| b. Contamination of labeling glue. | Clean all metal gluing parts of the machine(such as glue pots, roll, scraper, picks, as well as mixing paddles,
scoops, or glue pails) with boiling water and antiseptic. Rubber rollers and wipers should be washed with luke warm water. Use only clean water for diluting the glue. Keep glue barrel covered when not in use. Consult glue supplier if trouble persists. |
| c. Storage of labeled bottles in a damp location. | Store labeled bottles in a clean, dry location. |
| d. Inefficient cleaning action of bottle soaker. | Clean the soaker with the frequency prescribed by the manufacturer of the unit. See also "13-Foaming in the Soaker". |