HIGH SOLVENT RESISTANCE
8000 Series material has been designed to provide a solution to more extreme applications. The 8000 Series is at the forefront of our ongoing development programme, which results in innovative and practical solutions to the problems created at the boundaries of screen printing development. It offers extremely high chemical and solvent resistance to enable longer life and quality of print, when other products fail.
Screen Printing is a process in which a Squeegee Blade pushes Ink through a Screen, which has had areas blocked off by a stencil. The ink is then pushed though the areas of mesh that have not been blocked, printing an image on the substrate. Using several screens, multiple colours can be applied. Screen printing is arguably the most versatile of printing techniques and is valued for its ability to print on a wide variety of materials with flexibility. Also known as Silk Screen Printing, Serigraphy and Serigraph.
Watts Squeegee Blades are used in a wide variety of industries to produce many thousands of different products. Users vary from printers using hand held Squeegees in manual processes, to large Blue Chip companies running state of the art factories.
Whatever the application, customers can be sure that Watts Squeegees will help them to achieve the desired print.
A number of common Screen Printing applications using Watts Squeegees are:
• CD / DVD Disc
• Electronic and Printed Circuit Board (PCB)
• Solar / Photo Voltaic (PV)
For the suitable material to use in each application, please see Watts Squeegee Materials
Size and Tolerance for specific profiles:
|G1, G5, G6||50 – 3715mm (+10mm / -0mm)||8 – 686mm (+ / -0.15mm)||3 – 12.5mm (+/- 0.25mm)|
|G2, G3, G4||50 – 3450mm (+ / -15mm)||15 – 55mm (+ / -0.5mm)||3 – 12.5mm (+/- 0.25mm)|
|G18||2000mm (+0mm / -10mm)||20-50mm (+ / -1mm)||9mm (+/- 0.25mm)|
|G25||50mm – 3715mm (+/- 1mm)||9 – 12.5mm (+/-0.15mm)||9mm –12.5mm (+/- 0.15mm)|
|G30||50mm – 2800mm||25 – 140mm||5 – 10mm|
|G30R||50mm – 2800mm||25 – 50mm||2 – 4mm|
Note that the above specifications are standard and can vary depending on the grade of material requested.
7000 Series: 45 – 90 Shore A
2000 Series: 60 – 90 Shore A
8000 Series: 60 – 90 Shore A
5000 Series: 55 – 95 Shore A
Although polyurethane is generally recognised as being highly resistance to solvents, it must be noted that all polyurethanes absorb solvents. Resistance to solvent swelling is increased with hardness.
The ability of the polyurethane formula to resist edge breakdown when subjected to solvent ingression is vital in Screen Printing. Watts Squeegee Blades, unlike many others, are formulated especially to withstand this absorption, with the 8000 Series showing amongst the highest UV Chemical and Solvent resistance of any product in the market. These formulas are the result of many years experience.
Colour Change in 5000 Series
The Watts 5000 Series material is a Vulkollan® material, made under licence from Bayer AG. Once processed, the material is sensitive to UV light and is therefore stored away from natural light. To maintain the colour the material must not be exposed to light for prolonged periods of time. If left in sunlight, the material will rapidly darken until almost black. This colour change has no influence on the physical properties and is purely an aesthetic effect.
Do not sharpen a new Watts blade – take advantage of the perfect edges. All Watts Squeegee Blades can be re-sharpened. Rest the blade for at least 24 hours before re-sharpening and as Watts Squeegee Blades are designed especially to be abrasion resistance, be careful not to generate too much heat. Apply little pressure and for short time periods.
Blade life is increased through periods of “rest”. If you use two pieces one can be “rested” whilst the other one is used.
Moulded blades are heat sealed at the time of manufacture. This sealed surface resists the ingression of solvents for slightly longer periods of time. Advances in materials such as the 8000 Series mean that cut products offer extremely high levels of resistance and therefore similar life expectancy, at far more competitive prices and enabling the use of the perfect cut edges. The 8000 Series can also be re-sharpened, unlike the moulded products.