Fluorescent Glass MicrospheresPosted on May 19th, 2016 Microparticles Expert
Solid glass microspheres hemispherically coated with fluorescent coatings, a fluorescent coating is precisely applied to half of the core sphere, making the glass spheres appear colorful and fluorescent at daylight and exhibit bright fluorescent response under UV light. Fluorescent coatings are available in seven standard colors, with three options for glass cores available for customers who require a fluorescent tracer of a specific emission spectra and density. Fluorescent coatings can also be applied to other microsphere cores on special request, exact size range options vary by material. For PIV applications that typically use green lasers (530nm) as excitation sources, we recommend utilizing our fluorescent red coating in conjunction with a 570-580nm high pass filter so only the fluorescent particles will be visible during imaging.
Seven standard fluorescent color coating options on glass with broad spectrum responses:
Fluorescent Blue Glass (445nm peak emission) at 407nm excitation
Fluorescent Green Glass (515nm peak emission) at 414nm excitation
Fluorescent Yellow Glass (525nm peak emission) at 485nm excitation
Fluorescent Orange-Yellow Glass (594nm peak emission) at 460nm excitation
Fluorescent Orange Glass (606nm peak emission) at 577nm excitation
Fluorescent Red Glass (607nm peak emission) at 585nm excitation
Fluorescent Violet Glass (636nm peak emission) at 584nm excitation
Janus (Micro) Particles – From 45um to 1mm+Posted on April 24th, 2015 Microparticles Expert
Cospheric offers unique capability to manufacture Janus microspheres and micro-particles with partial coatings and dual functionality. Currently half-shell or hemispherical coatings can be applied to any sphere (glass, polymer, ceramic) in sizes 45micron in diameter on up to 1mm and higher. Hemispherical coatings of less than 1 micron with tolerances as low as 0.25 micron have been routinely demonstrated. Color combinations are truly unlimited. White, black, silver, blue, green, red, yellow, brown, purple in both fluorescent and non-fluorescent have been made. Sphericity of greater than 90% and custom particle size ranges are offered.
The custom coating capability offers customers the ability to create fluorescent glass micro-spheres of the specific size and emission/excitation needed. As the micro spheres and coating are solvent resistant
they work ideally as fluorescent tracers or highly visible targets. We can overcoat clear glass or silver coated glass for the effect needed.
For those needing very large Spheres Cospheric can coat spheres of 1mm and larger.
Janus microparticles are now available as either dry powder or in a diellectric oil.
Stainless Steel MicrospheresPosted on April 24th, 2015 Microparticles Expert
300 Series stainless steel is well known for its corrosion resistant properties. Now Scientists are demanding high quality spherical stainless steel microspheres which offer high density (7.8g/cc), high sphericity (>90% round) and corrosion resistance (300 series stainless steel).
A full range of precision sizes are now available from 1-22um on up to 1.0-1.2mm.
Applications for Stainless steel spheres include.
1) Conductive Spacers
2) High Density Projectiles
3) Charge Transport
4) Shock Absorbtion
Research vial quantities are listed, many sizes have kg quantities in stock for larger project needs.
Large Polystyrene Spheres AvailablePosted on September 9th, 2014 Microparticles Expert
High Quality precision Large Polystyrene Spheres now available.
Sizes of 2mm and 4.4mm.
Having a density of 1.05g/cc size ranges as narrow as CV=0.2% these are excellent for research applications
Glass Microspheres Used in Studying Self-Cleaning Gecko-Inspired AdhesivesPosted on September 9th, 2014 Microparticles Expert
Researchers from Carnegie Melon University and Karlsruhe Institute of Technology have recently published an article in Journal of the Royal Society titled Staying Sticky: Contact Self-Cleaning of Gecko-Inspired Adhesives that presents the first gecko-inspired adhesive that matches both the attachment and self-cleaning properties of gecko’s foot on a smooth surface.
Using glass microspheres to simulate contamination the scientists created a synthetic gecko adhesive that could self-clean and recover lost adhesion. Real world applications of self-cleaning adhesives are reusable adhesive tapes, clothing, medical adhesives (bandages) and pick-and-place robots, among others.
Everyday challenge with traditional adhesives is that they loose their stickiness once contaminated. Geckos have been intriguing researchers for decades because of their unique and striking capability to maintain the stickiness of their toes through contact self-cleaning. They can travel up the walls and ceilings in a wide variety of “dirty” settings retaining adhesion.
Upon experimentation, scientists discovered that the critical variable is the relative size of microfibers that make up the adhesive compared to the diameter of contaminant particles. Glass microspheres were used in diameters from 3 to 215microns. Glass microspheres were packed in air and used as supplied. Contamination of the samples was achieved by brining each sample in contact with a monolayer of glass microspheres with specific speeds under predetermined compressive loads. The cleaning process involved a load-drag-unload procedure.
Best self-cleaning results were obtained with the largest contaminants (glass microspheres), with the size of the adhesive fiber much smaller than the contaminating particle. This information is important to know when designing self-cleaning adhesives—make the adhesive fibers much smaller for improved adhesion recovery. This cleaning mechanism requires unloading particles by dragging. The other extreme of contaminating microspheres being much smaller than the adhesive fibers has advantages in some situations, even though it works by a different mechanism. Smaller microspheres tended to become embedded into the adhesive material. Particle embedding is a temporary cleaning process but might be sufficient in some applications.