Auto Service World
Feature   October 1, 2007   by Auto Service World

Countertalk: Knowledge Building: A Waterborne Q&A For Jobbers

The looming waterborne paint issue is one that has many in the repair industry concerned and more than a little confused. With the help of our friends in the collision repair business, we’ve compiled a list of frequently asked questions of which jobbers should be aware in order to assist their customers.

What are the proposed low-VOC regulations and how will they affect the collision repair industry?

The proposed regulations would limit the amount of volatile organic compound (VOC) emitted by automotive refinish coatings and surface cleaners. The most significant effect on the collision repair industry will be the need to switch to waterborne basecoats in order to meet the new VOC limits. Environment Canada’s proposed regulations prohibit the sale and import of non-compliant products, rather than prohibiting shops from using these products.

Why are regulations concerning automotive refinish coatings being developed?

The Government of Canada is working to reduce emissions of air pollutants. The coatings and surface cleaners used in auto refinish operations contain solvents that evaporate to the atmosphere during surface preparation, coating application, and clean-up. These solvents contain volatile organic compounds (VOCs), which are precursors to particulate matter and ozone, the key ingredients of smog. It is estimated that over 5 kilotonnes of VOCs are emitted each year from coatings and surface cleaners used in automotive refinishing operations in Canada. The proposed regulations would reduce annual VOC emissions by approximately 40%.

What coatings are affected by the proposed regulations?

Environment Canada’s proposed VOC-limit regulations apply to automotive refinish coatings and surface cleaners which are applied to motor vehicles and mobile equipment (including cars, motorcycles, trucks, truck trailers, street cleaners, and farm equipment) to refinish or decorate the surface.

What is being considered for the proposed regulations?

The intent of the proposed regulations would be to set mandatory limits on the VOC content of automotive refinish coatings. The regulations would affect the manufacture, import, and sale of these products in Canada. The regulations could apply as soon as January 1, 2009.

The proposed regulations would also set a VOC content limit of 50 grams per litre (as mixed) for surface cleaners, materials used for surface preparation prior to coating. The proposed regulations would not apply to coatings and surface cleaners sold in small containers (less than 0.5 fluid ounces); sold in non-refillable aerosol containers; and those applied during the original manufacture of motor vehicles, mobile equipment, or associated parts and components.

How can collision repair shops prepare for the regulations?

Collision repair shops can discuss with their product suppliers whether different products would be offered to comply with the proposed regulations, and whether any training or other preparations may be necessary. The intent of the proposed regulations would be to allow collision repair shops to use up any remaining non-compliant product, including colour tints, purchased prior to the effective date of the regulations. However, shops would not be allowed to purchase or import additional non-compliant product after the effective date.

Will shops need to purchase any new or special equipment from jobbers to spray waterborne basecoats?

A lot will depend on the equipment that the shop already has in place. With waterborne technology, it is beneficial to have some degree of climate control (temperature and humidity). A down-draft booth with air make-up is desirable. Assuming the shop is well equipped, some small upgrades will be useful to take full advantage of waterborne basecoat characteristics. For a down-draft booth, air blowers that create turbulent air over the wet basecoat give a great productivity boost. Several options exist that can be integrated into the spray, dry, and cure cycle of a down-draft booth. Shops can also benefit from portable blower systems, which offer the same drying productivity noted above and are fairly low cost. Their limitations are the size of the repair and the ability to create the turbulent air over the entire repair surface. The incentive for these blowers is the reduction of dry times to about 15 minutes from 30 to 60 minutes, depending on film thickness and climate. The blowers will be essential in conditions of very high humidity. Additional equipment will include dedicated waterborne basecoat spray guns and gun washer, separate waste streams and waste removal. Plastic or lined cans, plastic paint sticks, and nylon mesh strainers will be needed. Higher quality tape and masking supplies, as well as improved housekeeping in the paint department, will also be useful. Recommended capabilities for a well-equipped shop include air flow greater than 11,000 ft/min, minimum air speed of 0.6 ft/s; uniform vertical air flow; efficient/sufficient heating systems; and clean and sufficient process air for spray guns and air blowers.

How will Environment Canada enforce this legislation?

The proposed legislation is a prohibition of sale. That means paint companies and jobbers will not be able to sell any non-compliant product past the proposed date of Jan. 1, 2009, and it will also be illegal for a shop to import any non-compliant material. Canada Customs will audit any importation of coatings. There are federal auditors in place, there have been enforcement agreements with provincial government agencies, and there will be audits at the shop level with non-compliance resulting in heavy fines.

What is the difference between waterborne and solvent-borne basecoat?

Waterborne coating material is suspended in the water carrier, instead of having the coating material dissolved in solvents. To envision this, imagine an oil and vinegar salad dressing, and how the oil becomes suspended in the vinegar when mixed. After the coating is applied, the water evaporates, leaving the coating materials.

What’s inside?

Typical waterborne basecoat:

Solvent content 10%

Solids content 20%

Water content 70%

Conventional base coat:

Solvent content 84%

Solids content 16%

What are the main concerns painters have with regard to colour matching?

The main concern with regard to colour matching is the difference in the appearance of waterborne products in the can and after application. In the can, waterborne coatings may appear milky and are not representative of the final dry coating. It is advisable to use a check panel for colour matching.

How does the productivity of waterborne basecoats compare with solvent-borne basecoats?

Waterborne basecoat can meet or exceed the productivity of solvent-borne basecoat in a well-equipped shop. Most waterborne basecoat colours hide in 1.5 coats with no flash between coats, providing a distinct productivity advantage compared with poor-hiding solvent-borne colours. For good hiding solvent-borne colours, the waterborne basecoat is equal or slightly faster for cycle time. Air blowing systems (booth or portable) will be key to achieve the productivity advantages of waterborne basecoats. The poorly equipped shop will be at the mercy of the ambient temperature and humidity for the region and the weather conditions of a given day.

Are waterborne basecoat products susceptible to freezing?

Yes, since some waterborne basecoat products are water-based, they can freeze if exposed to freezing temperatures, even if for a short period of time. Some waterborne products contain no water until they are prepared, and these are not susceptible to freezing. Temperature-controlled storage rooms and insulated delivery vehicles may be necessary to ensure the quality of the products.

Are waterborne basecoa
ts safer than solvent-borne basecoats?

Although waterborne basecoats are water-based and emit fewer solvents than traditional solvent-borne basecoats, they still contain dangerous chemicals that can be harmful if proper personal protection is not used when spraying or handling. It is suggested that shop personnel treat waterborne basecoats with the same respect as you would solvent-borne basecoats.

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