Minnesota Mining and Manufacturing Company

3M Innovative Properties Company

Kathleen A Hachey

Thomas P Hedblom

David C May

Thomas P Klun

William M Lamanna

Alan David Fanta

Kyung H Moh

James P Mathers

Kathleen M Humpal

Roger W Lange

Larry K Stump

Thomas V Kusilek

Chris J Goodbrake

Robert L Keech

Thomas E Forester

Terrance L Beseup

An antistatic composition comprises (a) at least one ionic salt consisting of a nonpolymeric nitrogen onium cation and a weakly coordinating fluoroorganic anion, the conjugate acid of the anion being a superacid; and (b) at least one thermoplastic polymer. The composition exhibits good antistatic performance over a wide range of humidity levels.

Antistatic composition

Durable retroreflective elements

A process and retroreflective elements are provided. The process of preparing a retroreflective element includes the steps of (a) combining a bed of optical elements and one or more core elements comprising a thermoplastic material; and (b) agitating the combination of optical elements and core elements for a sufficient period of time and at a sufficient temperature to coat the optical elements onto the core elements to form retroreflective elements.

Retroreflective elements

A pavement marking 10 includes a base sheet 12, a barrier layer 30, a layer 32 of bonding material, a multitude of optical elements 34, and skid-resistant particles 36. The base sheet 12 contains rubber and fillers and has a number of protuberances 14 projecting from its front side 28. Valleys 16 are disposed between the protuberances 14. The barrier layer 30 is disposed on the front side 28 at least in valleys 16 and preferably over protuberances 14. The layer 32 of bonding material is disposed predominantly on protuberances 14 and in this position secures the optical elements 34 and skid-resistant particles 36 to the protuberances 14 but not to the valleys 16. The coverage of the front side 28 of base sheet 12 with barrier layer 30 and bonding material 32 prevents the fillers in the base sheet 12 from becoming present on the top surface of the pavement marking 10 and thereby preserves the intended color of the marking 10.

Patterned chalk-resistant pavement marking and method of making

A retroreflective article and a method for making same are taught. The retroreflective article comprises transparent microspheres and both specular and diffuse reflective pigments dispersed in a binder layer. The utilization of both types of pigments results in improved retroreflectivity over a greater range of entrance angles than if only one or the other pigment alone were used.

Method for making retroreflective article with dual reflectors

Retroreflective article with dual reflector

Growing community of inventors

Hudson, WI, United States of America

Kathleen A Hachey