Adhesives Magazine

Bubble-Free Labels

September 1, 2009
Teamwork among converter, OEM and label supplier produces a solution for bubble-free label applications.

Not only is this information essential for consumer safety, but it helps reduce the possibility of manufacturer liability.


Manufacturers and converters in the outdoor power-equipment market know that the appearance of brand identification and safety/instructional labels sends a message to the consumer about product quality. Labels that retain their readability, adhesion and color quality for the life of the outdoor product reinforce the product’s reputation for quality and durability. Labels that are faded, peeling off, scratched, tunneled, flagged or otherwise flawed in appearance send a negative message about the quality of the product itself.

Recently, a South Dakota-based converter of custom-made screen process labels faced such an issue. The company, a FLEXcon customer, produced labels for a major OEM that specializes in premium outdoor power equipment such as lawn mowers and snow blowers. Printed on a thinner-gauge flexible white vinyl product, the labels were exhibiting bubbles, creating an unsightly appearance.

The converter had begun to use an alternative option - a polycarbonate film - to meet its customer’s label needs. However, that product was an unattractive option both in terms of appearance and higher cost. In addition, the polycarbonate product did not provide the five-year durability warranty that OEMs want for their outdoor power equipment labels.

The converter was aware of more costly film solutions available that effectively solve the bubble problem. For example, channels or beads are used in the adhesive layer that allow air to escape; however, the process for creating these channels/beads requires an expensive product design that contributes to their premium cost. The pattern from the channels or beads can transfer to the label surface and is visible in printed graphics. In addition, not all of these products offered a five-year durability warranty. The label converter decided this was not a viable solution for their OEM customer.

The label converter asked labeling materials supplier FLEXcon Co. Inc. to join the converter/OEM team, observe the bubbling problem and propose a solution with the necessary outdoor durability and UV resistance. The solution needed to not only resolve the bubbling issue, but be easy to apply, highly durable, and more cost-effective than currently available products for bubble-free labels.

Easy to Apply

The OEM uses temporary, seasonal workers for applying labels to their seasonal products, such as snow throwers, walk-behind lawnmowers, zero-turn mowers, and riding mowers. Ease of application is essential because these workers have varied skill levels, are not formally trained on how to apply the labels, and must maintain a desired output per hour.

Highly Durable

The OEM’s outdoor products for consumer and commercial use are noted for their high quality and long life. The bubble-free label solution needed to have guaranteed five-year outdoor durability to provide the highest aesthetic quality and performance for the life of the product.

Beyond durability and being bubble free, FLEXcon's DPM Aply 1000 comes from a pedigree of durable product marking films that preserve consumer perception of quality and minimize OEM liability.

More Cost-Effective

Because of the quantity of labels used per product, not to mention the total number of products output, the OEM wanted to obtain the highest label performance possible at a reasonable cost.

To find the appropriate solution, FLEXcon began by exploring the possibility that plastic outgassing might be causing the bubbling issue. Outgassing is a function of freshly molded plastic parts, which cure over a 72-hour period. Within that period, plastic parts often emit air molecules that can become trapped under the label. FLEXcon learned that the labels were usually applied well after the typical 72-hour cure period for newly molded plastic parts. In fact, the typical application of labels takes place 5-10 days after the product is manufactured. This indicated that outgassing was not the primary cause of bubbling. In addition, bubbles appeared on labels applied to the OEM’s painted metal surfaces, where plastic curing time is not a factor. A more likely explanation for the bubbling, therefore, would be either complexities or challenges during the application process or a product performance issue.

To explore both possibilities, FLEXcon observed how the OEM’s workers applied the labels. There were a number of inconsistencies in technique, including how the release liner was removed, how the label was laid down, and the method used to smooth it out (via hand or squeegee). In addition, they saw how the current label material and a control label material functioned during the same application process.

Based on its market research, FLEXcon was aware that 90% of OEM label bubbling problems are caused by application air entrapment and inadequate product performance as the labels are applied, not by outgassing. Therefore, a custom film/adhesive solution that would facilitate consistent, precise application seemed to be the answer to this customer’s challenge.

After testing a variety of custom film constructions, FLEXcon arrived at a specially engineered product featuring a film with more rigidity than the previous labeling product coupled with a specifically formulated adhesive. The film’s rigidity would make it easier for any worker to apply the label smoothly and consistently since it would hold its shape while being affixed. This film’s smooth, non-patterned surface and opaqueness would achieve optimum label graphics. The adhesive was designed to offer easy repositionability and a reliable long-term bond that would keep the label in place for the life of the product.

FLEXcon provided samples of the custom film/adhesive construction to the converter and the OEM. A side-by-side comparison with the previous thinner-gauge vinyl product showed that the new FLEXcon solution was easier to apply, did a better job of preventing bubbles, provided print quality deemed superior to other solutions on the market, and could do the job in a more cost-effective way. This film product has been added to FLEXcon’s product line and is now available to all converters under the name DPM® AplyTM* 1000.

The converter and its OEM customer were pleased with this solution, and plan to transition to the specially engineered film product for the majority of their outdoor power equipment labels that formerly used the thinner-gauge vinyl product or the polycarbonate. Of special importance, the FLEXcon solution comes with a five-year outdoor durability warranty.

By working as a three-party problem-solving team, the converter, OEM, and FLEXcon were able to combine their knowledge and capabilities to find a way to hold down costs for bubble-free labeling while achieving a superior aesthetic result.

For more information, contact the FLEXcon Product Identification Business Team at (508) 885-8300.