ASTM International

Paint and Coating Testing Manual: Fifteenth Edition of the Gardner-Sward Handbook - 15th Edition
 N MNL17

Annotation

Introduction

PAST TO PRESENT

The previous edition of this manual, the 14th, described in detail the changes that took place in the coating industry from the early 1970s to the early- to mid-1990s. Published in 1995, the 14th edition classified powder coating, radiation-cured coatings, and higher-solids coatings as new, with a potentially reasonable growth curve. It noted that at the time, all liquid coatings were at higher solids content (lower volatile organic solvent content) than in the 1960s when Rule 66 came into being. Powder coating and radiation curing were sufficiently new enough that chapters related to testing them were not included in the manual. High-solids development still struggled with the difficulties of decreasing molecular weight for low viscosity purposes and achieving the low molecular weight with functionality on all molecules that quality coatings require. However, the solids level has increased in solvent-based coatings and achievements have been realized in decreasing volatile organic content (VOC).

Since that time, powder coating has exploded. Today the technology is well established, has a significant share of the coatings market, is internationally accepted, and has a strong technical society that aids in future growth. To illustrate the widespread acceptance of powder coatings, one merely needs to look at advertisements. Outdoor metal furniture advertisements, for example, proudly include words that imply quality and durability-that is to say, "powdercoated finishes."

Of course, such furniture certainly is not the only commercial outlet for powder coatings. Applications include lighting fixtures, tubing and aerosol cans, automobile and bicycle wheels, rebars, store fixtures, agriculture and construction materials, and on and on. Initially, colors and color changeovers were considered to be a major obstacle to powder coating development, but today a broad variety of colors is available, including many metallic and special effect finishes with abrasion resistance, brilliance, and overall high quality. Powder coating provides quality, economy in manufacturing space, increased production, energy usage reduction, and other facets important to product development and sales in today's marketplace.