Guide for the Correct Usage of Self Adhesive Materials
Storage
Rolls should be stored on end to avoid pressure marking. Extremes in temperature and humidity should be avoided. High temperature can lead to adhesive bleed, causing problems in particular with sprocketed material, whilst humidity may cause problems with the backing papers, such as curling, etc. All
self adhesive vinyl's should be allowed 24 hours to acclimatize to work shop humidity and temperature levels, before using. An ideal storage condition recommended is 15 degrees C to 25 degrees C and at 50% relative humidity. Avoid storing in direct sunlight or near a source of heating. Keep the rolls off the floor, as dampness from the floor may be absorbed into the backing paper.
Cutting
Ensure the depth / pressure setting of the
plotter blade is correct for the type of vinyl being used. Not cutting deep enough will create difficulties in weeding the waste matrix. However, cutting too deeply into the backing paper may cause delamination of the paper onto the adhesive side of the vinyl when removing the cut lettering from the backing paper. It is always good practice to test cut the vinyl, by creating some lettering in the same size as the finished work. Cutting the vinyl and leaving for some time before the weeding process, may lead to difficulties in weeding the waste and removing the lettering. These problems are caused by the adhesive flowing back and are especially noticeable in warmer conditions. However, cold conditions may also cause the face of the film to harden and become brittle. This can cause the blade to skid across the surface and cause the film to break when weeding.
NB: In cold conditions we recommend the film be acclimatized to room temperature prior to cutting.
Weeding
This is the process and the name given to the removal of the waste matrix, prior to transfer of the cut lettering.
Tweezers and
scalpels are the most common tools used for weeding. To begin the process, start at one corner and work across the image in short diagonal movements, usually in a right to left direction.
Transfer of the Pre-Spaced Image
Once the waste matrix is weeded away, the cut lettering then has to be transferred accurately from the backing paper to the finished substrate, using application tape (this is similar to masking tape). We stock Kleentear application tape to successfully achieve this. As a general rule, matt finish vinyl's require a higher tack application tape than say a gloss vinyl. Smaller images require a higher tack tape than larger ones. No one tape will be ideal for all jobs, however our
Kleentear high tack and medium tack application tapes are all purpose and work for most applications.
Apply the application tape smoothly to the weeded image, avoiding wrinkles and bubbles wherever possible. Begin from the centre and work outwards using a
plastic applicator. Turn the vinyl over, so that the application tape is facing down on the bench and the backing paper is facing upwards. Remove the backing paper starting at one corner and peeling back diagonally at an angle of 180 degrees.
Removal of Existing Vinyl Lettering
To remove old lettering, use a heat source i.e. a hair dryer or heat gun, to soften the vinyl, then strip the vinyl slowly off the substrate. This tends to leave a residue of adhesive on the substrate. Using adhesive remover,
RAPIDREMOVER, spray the adhesive residue and let it penetrate for 30-60 seconds. Use an applicator to remove as much of the adhesive as possible.
The next step is to spray some RAPIDREMOVER onto a cloth and wipe the area clean. Finally, clean the entire area with detergent and water. The substrate must be free from grease, dirt and foreign matter prior to application. The safest and easiest way to clean and degrease the surface is to use
RAPIDPREP, a non toxic, degreasing agent that removes most waxes and silicones. This will thoroughly degrease the surface in preparation for the application of the vinyl graphic.
Application of the Pre-Spaced Image
There are two basic methods of applying self adhesive vinyls, depending of the size / complexity of the image and difficulty of the substrate. In all cases, ensure that the sign is applied above the
minimum recommended application temperature.
See technical data sheets for temperatures of each vinyl product. Please note that these are minimum temperatures. Most good self adhesive manufacturers recommend the range of 15 degrees C to 25 degrees C as the ideal temperatures for the application of self adhesive vinyls.
Dry Application - used in the majority of cases.
Wet Application - used to apply large or multi-coloured images to difficult substrates i.e. convex or concave curvatures. Also recommended for application onto a glass surface.
One of the secrets of good long term application is to have optimum contact of the adhesive to the surface. Any gaps between the adhesive and the surface will inevitably, through time, lead to adhesive failure.
Dry Application Top Hinge Method
Before commencing, establish exactly where on the substrate the sign is to be located, then tape the sign into position using small pieces of masking tape. Use
50mm masking tape to create a hinge - half the masking tape on top of the sign and the other half on the application surface. Squeegee the masking tape hinge firmly into position. To apply, lift the sign away from the surface and fold back on the hinge. Peel off about 150mm of the backing paper then lower the sign, keeping the adhesive away from the application surface. Starting at the top in the centre, squeegee down and outwards towards each edge in turn. Remove another 150mm of backing paper and keep repeating the process, using overlapping strokes until the sign is completely applied (for large pre-spaced signs, do as above but slit between each letter, so that every letter can be applied individually). Now carefully remove the application tape, diagonally at 180 degrees. Air bubbles can be removed by puncturing the bubble with a pin and squeegee the trapped air towards and out of the puncture. Finally re-squeegee the sign, paying particular attention to the top and leading edges. If the sign is long and narrow the same procedure can be adopted with the hinge on the edge of the sign instead of the top.
Wet Application
This method is used when applying large or multi-coloured signs and assists greatly in the elimination of air bubbles. The application of a liquid to the adhesive forms a barrier, which temporarily neutralises the adhesive and allows the legend to be repositioned several times.
Soapy Water
Use a lukewarm solution of warm and enzyme free washing up liquid: ratio one tablespoon per bucket of water. Damp down adhesive using a sponge or fine water spray or wet substrate with solution, to allow the sign to be floated into position. When positioned damp sign down to hold it in place. Next, squeegee image, working from centre outwards to edges. This should remove as much of the water solutions as possible, to enable adhesive action to commence. After 30-60 minutes (some manufacturers recommend 24-48 hours) re-squeegee the entire image ensuring maximum evacuation of the solution to give maximum adhesion. Carefully remove application tape diagonally at 180 degrees, ensuring that sufficient adhesion has been reached by the lettering. Finally re-squeegee over the entire sign, paying particular attention to the top and leading edges.
Application Fluid
Alternatively instead of water solution an application fluid such as
RAPIDTAC can be used. Shake the fluid well before use. Spray fluid onto adhesive or the substrate and float the image into position as before. Excessive use of the fluid will result in longer cure times for the adhesive so use sparingly. Squeegee the image as before. After a few minutes spray the application tape with RAPIDTAC and squeegee again. Carefully remove the wet application tape diagonally at 180 degrees. Finally re-squeegee over the entire sign again, paying particular attention to the top and leading edges.
Independent laboratory tests show that RAPIDTAC, in comparison to soapy water, could significantly improve the adhesive bond, showing 300% better adhesive after 6 hours, 50% after 24 hours and a 10% improvement in the overall adhesion peel values.
Use of Heat
When applying to substrates with complex profiles i.e. rivets, to attain the best results use a hair dryer or heat gun to soften the film, making it more pliable. Squeegee the film onto and around the rivet in order that the adhesive makes contact with the entire area. Remove any trapped air, by puncturing and then re-squeegee ensuring full contact with the substrate.
NB: For complex surfaces such as above, a cast vinyl would be recommended.
CAUTIONARY NOTES
The Following information is a general guide for the use of self-adhesive materials.
Hot Weather
Heat causes the adhesive to become more viscous and tacky and softens the face of the film. Therefore avoid applications in direct sunlight and excess heat, as the adhesive tends to grap at the substrate on impact.
Cold Weather
Cold causes the film face to harden, becoming brittle resulting in problems with weeding. It can also impede adhesion making the adhesive less viscous; extra care therefore must be taken when handling the products. Make sure the minimum temperature for the vinyl used is adhered to i.e. in general 10 degrees. Application during cold weather may make it necessary to use a new blade when cutting, to ensure blade does not skid over surface of film. Whenever possible allow film to acclimatize to room temperature prior to cutting and weeding.
Wet Application
Water freezes - avoid wet application during freezing weather conditions.
Cleanliness
All substrates must be clean, degreased and free from dirt or foreign matter. Degrease substrate using RADIPPREP prior to application. Correct cleaning and application will significantly improve the performance of the self adhesive material.
Washing
It is important that after application of a sign to a vehicle, the vehicle should not be washed for several days. Care must be taken when using power washers as these can remove or damage vinyl lettering if too powerful or directed at an angle to the lettering.
Printing
NB: If printing, it is the responsibility of the purchaser to test for ink compatibility.
Out-Gassing
Some plastic materials i.e. polycarbonate, acrylic and fibreglass can out-gas, this causes bubbling in the film and the eventual failure of the adhesive. Out-gassing can similarly occur, when self adhesive films are applied to a newly painted surface. For example, when using two pack paints, most paint manufacturers recommend a drying time of at lease twelve hours at 20 degrees C. Our experience suggests that this can be an insufficient drying time before the application of self adhesive films. We currently recommend a curing time of at least 72 hours.
Plasticiser Migration
Some flexible P.V.C. substrates i.e. banners, curtain sides and other P.V.C. films, contain plasticisers to varying degrees. Heavily plasticised films have a tendency to 'leach out' plasticisers during their lifetime. Therefore when a self-adhesive film is applied to this type of substrate, the plasticisers in the substrate will migrate out and start to breakdown the adhesive. Over time this can lead to adhesion problems, cracking the graphics and staining the substrate. The use of a film such as
MACsoft 900 banner range, which has a greater plasticiser resistant adhesive, could help overcome some of these problems.
Adhesive Milking
Some water or aqueous based adhesives will turn 'white or milky' when in contact with water, this can look unsightly on glass substrates. The milking will disappear after several hours, occasionally even longer, this depends on the film being used and the atmospheric conditions. The use of RAPIDTAC will eliminate or reduce this milking effect.