Recommended Techniques for Washing Glass

1 Glass technical Document TD-144. Recommended Techniques for Washing Glass Prologue Whatever the job and whichever Glass product is chosen, the attractive and efficient This document is a reproduction of the use of Glass requires a clean Glass surface. original publication, with only minor With more than 120 years in Glass changes and updating. The original manufacturing and fabrication, PPG offers publication was introduced over 20 years the recommendations in this document to ago and remains one of the most requested assist Glass fabricators successfully wash the and helpful resources on Techniques for Glass products that PPG is pleased to furnish Washing Glass .

2 While most of the principles them. The included recommendations are and recommendations for the machine based on detailed research, years of first- Washing of Glass remain applicable, Table 1. hand production experience, and work in has been deleted, since the Glass cleaning solving hundreds of customer related Glass - product information shown was obviously cleaning problems. dated. In addition, the introduction of new performance enhancing low-e coatings, such Included in this document is a detailed as Solarban 60, Solarban 70, Solarban 80 review of: Solarban z50 coated Glass , have led to Dirt types that affect Glass additional recommendations that are noted in this update.

3 Glass surface protection Introduction Water and detergent requirements Mechanical washers The durability and beauty of Glass , coupled with its transparency, make it one of the Prewashing world's most utilized building materials. Requirements for Low-E Glass Glass allows light to enter the building, Washing system maintenance while providing protection from the Troubleshooting elements. And, it allows occupants the connection to the outside environment that Glass Surfaces: Cleanliness & Protection has been proven to improve morale and productivity.

4 Because dirt negatively affects Glass undergoing any type of processing, Glass Glass is available in a wide variety of tints surfaces must be clean. Proper cleanliness that provide aesthetic variety, as well as requires that the Glass surfaces be washed improved energy efficiency and occupant effectively. comfort. In addition, aesthetics, comfort and energy efficiency can be further enhanced through the use of the many types of coatings that have been developed for application to the Glass . Page 1 of 19.

5 PPG Industries, Inc. Glass technical Document TD-144. When Glass is dirty , both its aesthetic and units, or for fabricators who coat, temper, or performance quality may be diminished. If etch Glass and require exceptional Glass dirt is not removed effectively, it will inhibit cleanliness prior to final processing. processes where the adhesion of other materials (sealants, coatings, etc.) to Glass is Dirt on Glass surfaces can be grouped into necessary. For example, when Glass is used four general categories: for mirror and architectural coating particulates applications, the surface must be clean in order to permit metals or metal oxides to surface residues bond to the Glass .

6 Insulating Glass reaction contaminants fabrication processes require clean Glass for surface corrosion the sealants to adhere properly to the Glass , since this bond provides the required long- Glass fabricators usually encounter only the term performance of the hermetic seal. first two types of dirt and these will be the Glass processes such as heat-strengthening, primary focus of this document. tempering, and bending require clean Glass Particulates are solid materials, loosely to minimize bull's-eyes distortion, burn, and deposited on the Glass surface, that can best other dirt influenced effects.

7 Be removed with non-abrasive mechanical methods such as a high pressure water spray. Typical Glass surface particulates What Makes Glass Dirty include paper interleaving fibers, acrylic Dirt on Glass can best be defined as any beads, wood flour and other powder unwanted material on the Glass surface . interleaving materials, Glass handling chips, Consider Glass interleaving, for example. wood splinters, cardboard pieces, and other Interleaving materials are essential for the packaging materials. See Figure 1 for an protection of Glass surfaces and coatings example of a typical particulate.

8 During transport and storage. However, Surface residues are contaminants that may when Glass is prepared for any fabricating be cleaned from Glass using detergent process, the interleaving becomes an Washing solutions and/or mechanical unwanted contaminant, or dirt , that must scrubbing Techniques . Examples of such be removed from the Glass surface. residues are fingerprints, paper scum, and cutting oils. An example of paper scum is The degree of dirtiness or cleanliness of shown in figure 2. Glass that is acceptable is dependent on the end-use of the Glass .

9 For example, Glass cleanliness that is sufficient for picture frame applications (in which the surface remains accessible for repeated future cleaning) may not be acceptable to the insulating Glass fabricator, who permanently seals Glass surfaces within insulating Glass Page 2 of 19. PPG Industries, Inc. Glass technical Document TD-144. Reaction Contaminates are more tenacious inventory, and practice stock rotation. With than surface residues and may physically or the increased use of MSVD low-e products, chemically bond or interact with the Glass such as Solarban 60 low-e coated Glass , the surface.

10 For this reason, their removal may proper storage of Glass inventory becomes require chemical undercutting with a even more important, as these types of Glass cleaning solution tailored for specific are more sensitive to moisture. dissolution or bondbreaking. In its initial stage, Glass surface corrosion is Hard-water salts are a commonly visible only under critical light (or encountered reaction contaminant. In some occasionally after coating application) and parts of the country, water supplies contain cannot be observed by the naked eye.