3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

Other

Geoffrey P Morris

Robert S Moshrefzadeh

Hsin-hsin Chou

Steven D Theiss

William E Wyllie, Ii

Leo A Meyer

Jacqueline C Rolfs

Billy J Tompkins

Thomas N Davis

Kenton D Budd

Chester A Bacon, Jr

Wallace K Bingham

Richard M Fischer, Jr

Warren D Ketola

James A Stevenson

Bradley D Guth

Glass microbubbles include on an average weight basis: from 25.0 to 37.4 percent by weight of silicon; from 5.7 to 8.6 percent by weight of calcium; from 5.2 to 14.9 percent by weight, on a total combined weight basis, of at least one of sodium or potassium; from 0.3 to 0.9 percent of boron; and from 0.9 to 2.6 percent of phosphorus, wherein the weight ratio of phosphorus to boron is in the range of from 1.4 to 4.2, and wherein the glass microbubbles comprise less than 0.4 percent by weight of zinc. A raw product including the glass microbubbles, and methods of making the raw product are also disclosed.

Glass microbubbles, raw product, and methods of making the same

Provided are dental articles, and methods of making articles, having an aesthetic inorganic coating based on zirconia at least partially stabilized with yttrium oxide, calcium oxide, cerium oxide, or magnesium oxide. Stabilized zirconia coatings were found to provide a smooth, low friction surface having high abrasion resistance. These coatings are particularly applicable to orthodontic appliances. While virgin stabilized zirconia coatings can often have an undesirable color cast, it was discovered that this color cast can be substantially eliminated by heat treating the coated appliance in an oxygenated environment. The combination of depositing a stabilized zirconia coating and subsequently heat treating to decolorize the coating provides a surprisingly robust, stable, low-friction coating that is also aesthetic.

Coated dental articles and related methods of manufacture

The invention relates to optical filters comprising an opacified portion. The optical filters are preferably suitable for use in illuminators for weathering devices.

Optical filters comprising opacified portion

Glass microspheres and rear projection screens containing glass microspheres, which combine a desirable index of refraction (preferably, no greater than about 1.70) and low levels of defects (e.g., bubbles, visible haziness, frostiness, or opacity, substantially nonspherical shapes) upon formation are provided. Also provided is a coating method of placing microspheres on a film for use in a rear projection screen.

Glass microspheres for use in films and projection screen displays

Projection screens and convenient and efficient methods of making such projection screens are provided. Recycled glass is reformed to provide glass microspheres of sufficient quality for use in a projection screen.

Projection screens and methods for making such projection screens

Glass microspheres for use in films and projection screen displays and methods

An acid-resistant glass article is provided comprising: about 25-45 wt-% SiO.sub.2 ; about 20-35 wt-% TiO.sub.2 ; less than about 5 wt-% B.sub.2 O.sub.3 ; about 15-40 wt-% of an alkaline earth modifier selected from the group consisting of BaO, SrO, and mixtures thereof; and no greater than about 25 wt-% of an alkali-metal oxide selected from the group consisting of Na.sub.2 O, K.sub.2 O, and mixtures thereof. The glass article is preferably in the form of a microsphere that is adapted for use as a retroreflective element in pavement markings.

Pavement marking tape comprising acid-resistant microspheres

Acid-resistant glass

Encapsulated retroreflective element comprising a retroreflective assembly made up of a transparent optical body and a reflective member and essentially completely encapsulated within a dense, substantially transparent oxide coating. Also a method for making such retroreflective elements and articles and compositions comprising such retroreflective elements.

Encapsulated retroreflective elements and method for making same

Colorant clusters comprising an aggregation of a plurality of grains of sol-derived material and colorant. The clusters are particularly useful as pigments in liquid compositions, e.g., paints and inks, for forming coatings that are retroreflective immediately upon drying. Also, a process for preparing such colorant clusters comprising admixing colorant in a binder sol to yield a pigment sol and then removing liquid medium from the pigment sol to yield the clusters. Also, a coating composition comprising retroreflective elements, a vehicle, and the aforementioned colorant clusters. After application of the composition to a substrate, the resultant coating is immediately retroreflective upon drying.

Growing community of inventors

White Bear Lake, MN, United States of America

Geoffrey P Morris