Learn what outgassing is and how to test a substrate prior to vinyl decoration.
Outgassing refers to the release of a gas from some
type of material. Natural materials, such as plywood, can outgas vapors as the
glues used in its manufacturing cure. Just about any synthetic substance will
outgas, too. The list of synthetic materials includes paint, polycarbonate and
fiberglass.
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| As a rule of thumb, polycarbonate sheets should be dried before decoration. Drying in recirculating oven at for 250° F for at least four hours will drive off any moisture vapor and oxygen within the sheet. |
Some materials, such as polycarbonate, outgas
because they absorb a vapor and then gradually release or “de-absorb” that
vapor. Other substances, such as paint, outgas the solvent within the mixture
cures. Fiberglass and other thermoplastics outgas as a byproduct of a
exothermic chemical reaction.
Some of manufactured materials will outgas within
days or weeks. Other substances take longer. Fiberglass, for example, can
continue to outgas for years. Low ambient temperatures can delay the process.
An automotive paint, which typically cure in 72 hours, can take much longer if
the vehicle is left outside in cold temperatures.
Outgassing frequently causes problems with applied
graphics. As the volatiles within the substrate migrate out of it, bubbles form
under the applied film. Some films allow gases to readily breathe through the
films. Some films don’t. This is a
substrate problem. It is not a film problem.
“Outgassing has been a problem for the electronic and
automotive industries for a long time,” says RTape’s Manager for Product
Development and Quality Assurance, Darryl Liedel. “When you buy a new car, that
distinctive “new car smell” is formaldehyde and other volatile vapors,” he adds.
“The smell of paint or fiberglass is also distinctive. These are gases that haven’t fully cured.”
“Any of the solvents that have not yet dried are caught
under the laminated film causing these bubbles,” says Liedel. “ The
larger the graphic, the worse this issue will be. With some smaller graphics,
the entrapped gasses can escape out the edge. With the larger graphics, the
path of least resistance for these gases is an air bubble.”
Testing Procedure. In some cases a material can pass the smell test, but is still emitting vapors. So how can you determine, if a substrate is still outgassing?
Here’s a simple test that you can perform. Apply a 6” x 6” piece of polyester film to the substrate in question. If the substrate is still outgassing, bubbles
will appear within 24 hours with ambient temperatures at or above 70⁰ F or (21⁰ C). If outgassing has
stopped, bubbles will not have formed and you should be good to go.
Vinyl Application Videos
Squeegee Technique. Nothing is more basic in vinyl application than the squeegee. But some squeegees work better than others. And there are right ways and wrong ways to use this simple tool. This video clip reviews squeegee selection, squeegee care and squeegee technique. Click to Link
Wet Applications. Dry applications are typically recommended for most vinyl applications. For those exceptions to the rule, this instructional video explains the right way to perform a wet application. Click to Link
Application of Window Graphics. Installing vinyl graphics on glass can be challenging, because the adhesive aggressively grabs onto this high energy surface. Repositioning graphics on window is generally difficult, if not impossible. This instructional video explains how to dry apply window graphics right the first time. It also describes the necessary steps required for surface preparation. Click to Link
Transferring Frosted Window Graphics Films. Because frosted window films are highly textured, transferring cut vinyl graphics can be problematic. This video provides direction in selection of the right application tape and how to apply these films quickly, easily and without problems. Click to Link
3-Step Surface Prep. This instructional video describes how to properly clean the surface of a vehicle before applying pressure sensitive vinyl graphics to a trailer or doing a full wrap of a car or van. This three step surface prep involves detergent washing, solvent cleaning and a final wipe down with IPA. Click to Link
Vinyl Application Over Rivets. Applying vinyl graphics on vehicle surfaces with rivets is challenging for most sign makers. Vinyl failures to these surfaces are all too common. This video demonstrates some tips and procedures, used by professional decal installers, which will make these demanding applications easier and more trouble-free. Click to Link
Vinyl Application to Corrugations. Learn how to apply vinyl graphics to corrugations in a relaxed state. Forcing films into the valleys of corrugations puts too much mechanical stress on the film. Sooner or later, the vinyl will lift or tent in valleys. Click to Link
Applying Air Egress Vinyls. Vinyl films with air egress release liners have almost eliminated bubbles and wrinkles from applied graphics. Air egress release liners with their highly textured surface structure are problematic. Not much will stick to these liners other than the vinyl film. At RTape our best premask solution for air egress liners is a special Conform® tape called 4761RLA. Click to Link
About Jim Hingst: After fourteen years as Business Development Manager at RTape, Jim Hingst retired. He was involved in many facets of the company’s business, including marketing, sales, product development and technical service.
Hingst began his career 42 years ago in the graphic arts field creating and producing advertising and promotional materials for a large test equipment manufacturer. Working for offset printers, large format screen printers, vinyl film manufacturers, and application tape companies, his experience included estimating, production planning, purchasing and production art, as well as sales and marketing. In his capacity as a salesman, Hingst was recognized with numerous sales achievement awards.
Drawing on his experience in production and as graphics installation subcontractor, Hingst provided the industry with practical advice, publishing more than 150 articles for publications, such as Signs Canada, SignCraft, Signs of the Times, Screen Printing, Sign and Digital Graphics and Sign Builder Illustrated. He also posted more than 325 stories on his blog (hingstssignpost.blogspot.com). In 2007 Hingst’s book, Vinyl Sign Techniques, was published. Vinyl Sign Techniques is available at sign supply distributors and at Amazon.
© 2016 Jim Hingst
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