Here's detailed information on solvents used in sign painting. Solvents described include Pure Gum Turpentine, Mineral Spirits, Lacquer Thinner, Toluene, VM&P Naphtha and Xylene. Hingst extensively covers solvent safety, the new safety data sheets and the HazCom2012 standards.
By Jim Hingst @hingst_jim
A solvent is any liquid that can dissolve another substance. That’s a fairly broad range that includes everything from acetone to water. Working with solvents is unavoidable for sign painters and most artists. Unless the solvent is water, all solvents are hazardous and nearly all are flammable. Even sweet smelling d-limonene is toxic. Yet, if you practice solvent safety you can limit the risk of these chemicals being inhaled or absorbed through your skin. Careless use of solvents can result in damage to your central nervous system, liver, kidneys and skin.
Solvent Safety
Recognize
the Risks. The first step to ensuring safe use of solvents in your
workplace or studio is to identify the hazards. Prior to working with any
solvents, alert your employees of the dangers of these substances. Avail them
of the appropriate safety data sheets (SDS) for these solvents, and provide
them with any required safety equipment (safety glasses, gloves, air
respirator) and appropriate training. Keep Safety Data Sheets (SDS) for any
solvents that you use in a binder accessible to your employees. In an
emergency, these bulletins can provide medical personnel with critical
information.
Labeling
Standards. Make sure that all containers for your solvents are
labeled in accordance with the HazCom2012 standards. You should also instruct
your employees on how to read the labels and recognize the terminology and pictograms
used to alert users of chemical hazards. For more information, see my article: How HazCom2012 Affects Your Business.
Good
Ventilation. Always work with solvents in a well
ventilated area of your shop.
Personal
Protective Equipment. Depending on the type of solvent used, you
and your employees could be required to wear safety equipment, which could
include protective eyewear (safety goggles or face shields), chemical resistant
gloves and air respirators.
If you are working in a
confined space, where it is impossible to reduce a high concentration of
solvent vapors, you should use an appropriate air respirator. When working with
this equipment, follow these rules:
- Make sure that the respirator is tight fitting to get the full benefit of the equipment.
- Provide employees necessary training.
- After using the respirator, remove the cartridges and store in an air tight container.
- Replace old cartridges.
Fire
Safety. Store solvents in a flameproof cabinet. Have dry
chemical fire extinguishers mounted in accessible places in the solvent storage
area and throughout your shop. Dispose of solvent laden rags in an airtight
metal fireproof container. For more information read my article on Solvents and Fire Safety. Prohibit smoking in all work areas of
your shop. For more information read my article on Fire Extinguishers.
Disposal.
Never dispose of solvents down the drain. Most likely this is an illegal
activity. In most cases, you should let
small amounts of waste solvents evaporate outside into the open air. Never
dispose of rags soaked in solvent into the garbage. In some cases, rags can
spontaneously ignite. If you have questions regarding disposal of waste
materials, solvent-laden rags and procedures covering accidental spills, call
your local governmental agency.
Product Evaluation
In evaluating which solvents
to use and stock in your shop you should consider a variety of factors listed
below. You can find much of this information in Safety Data Sheets for these
products.
• Application (the
recommended uses for a particular solvent)
• Evaporation Rate
(the time it takes for a solvent to evaporate)
• Flash Point (the
temperature at which a solvent can ignite)
• Flammability Rating
(rating on a scale of 0 lowest to 4 highest)
• Toxicity (the
exposure limits for the solvent. Exposure limits are often provided by government
agencies, such as OSHA, as a PEL or Permissible Exposure Limit value. The lower
the number, the more toxic the solvent is. For example, turpentine has a PEL
rating of 100ppm versus mineral spirits with a rating of 400ppm. Based on these
values, you would deduce that mineral spirits is less toxic than turpentine.)
Some solvents, when used as
a thinner or in paint mediums, can impart a yellowish hue to the painting. Prior
to using a solvent, it is best to Test,
Don’t Guess. To check the clarity of the solvent, brush a little of the
solvent on a bright white piece of paper. After the solvent evaporates, inspect
the appearance of the paper for any discoloration.
Many solvents can be used
for the same application. Each solvent,
however, has its own unique performance properties. The purpose of this story
is to review the most common sign painting solvents explaining recommended applications,
advantages and disadvantages, along with discussing procedures for safe
handling.
Pure Gum Turpentine
For many artists, old school
sign painters and pinstripers, there is nothing like the smell of pure gum
turpentine. It smells like a genuine sign shop or studio. I love the smell too.
The problem is that the fumes are toxic.
By the time you can smell
turpentine, it is already in your blood stream. For that reason, you should use
turpentine in a well-ventilated shop and only use it when you absolutely need
to. For cleaning your brushes, the slower evaporating mineral spirits (also
called white spirits) is a much less toxic alternative.
Nevertheless, many believe
that when turpentine is used safely, it is the best choice for thinning oil
paint or lettering enamel. And for all practical purposes, it is your only
choice when dissolving Damar resin or other resins.
Pure gum turpentine is made
by distilling pine tree sap. There is not much difference between pure gum
turpentine sold at your local hardware store and bottles of turpentine at the
art store other than the price. In my opinion, the difference is about the
significant as that between regular vegetables and organic vegetables. Both are
made the same way. Both look alike. The quality is the same. And both perform
identically.
In buying turpentine, inspect the clarity. It should be clear not yellow. When you buy turps, only buy in small quantities because it can yellow over time.
Applications:
Paint
thinner (excellent choice for artist’s oil paints and lettering enamels);
thinner for mediums; Damar resin solvent
Evaporation
Rate: Fast
Flash
Point: 95°F (35°C)
Flammability
Rating: Flammable
Exposure
Limits: OSHA PEL: TWA 100 ppm (560 mg/m3)
Mineral Spirits
For cleaning brushes and
thinning paint and varnish, mineral spirits is good alternative to turpentine. It
is also a cheaper alternative. While minerals spirits were originally developed
as a dry cleaning solvent, painters discovered that it did a great job of
cleaning brushes and thinning paints. Today, they are the most widely used
solvents in the painting field.
Compared to turpentine,
mineral spirits are also recognized as a much safer alternative. One reason is
that mineral spirits evaporate much slower than turps, which means that there
is much less of it in the air to breathe.
Mineral spirits is actually
a mixture of several different solvents distilled from petroleum. The
composition of that mixture can vary greatly from one manufacturer to another. That
could be a problem, because you never really know what you are getting. For
this reason, many of the old sign painters and artists use mineral spirits for
cleaning brushes but not for thinning paint and certainly not for making a
painting medium or Damar varnish.
Some painters prefer using
mineral spirits as a paint thinner because it evaporates more slowly than
turpentine. This gives the fine art painters a longer open time to manipulate
the paint. However, if you are in a rush, as many sign painters are, a slower
drying paint is not a benefit.
Applications:
Paint
thinner; brush cleaner, resin solvent
Evaporation
Rate: Slow
Flash
Point: 105°F (35°C)
Flammability
Rating: Combustible
Exposure
Limits: OSHA PEL: None
Denatured Ethyl Alcohol
Denatured alcohol is ethanol
to which toxic chemicals are added, so people don’t drink it. The problem with
denatured alcohol is that there is no telling what types of chemicals are used
and in what amount to make the alcohol undrinkable. It varies from one
manufacturer to another.
Generally, the chemicals don’t
affect the properties of the alcohol. For prepping vehicle surfaces prior to
vinyl application it is suitable. Isopropyl alcohol, however, is probably a
better choice, if cleanliness is a concern.
Denatured alcohol is also
used to dissolve shellac flakes. If you are a purist, you can buy a shellac
solvent from Tools for Working Wood. It is denatured ethanol with the least
amount of denaturant allowable it. It’s great for dissolving the flakes, but it
is expensive. In fact, it might be cheaper to use grain alcohol.
Applications:
Surface cleaner; shellac solvent
Evaporation
Rate: Fast
Flash
Point: 60°F (16°C)
Flammability
Rating: Highly Flammable
Exposure
Limits: OSHA PEL: TWA 1000 ppm (1900 mg/m3)
Lacquer Thinner
Lacquer thinner is composed
of many different solvents. It is a very volatile solvent. With respect to applications, I have listed
it as a brush cleaner. I only use it to wash out brush oil from my lettering or pinstriping brushes
immediately followed by rinsing the brush in mineral spirits. Many painters
won’t go near the stuff. I can damage brushes. If it use it as a substrate
cleaner, it can damage surfaces. The mixture of solvents in lacquer is also very
hazardous to your health.
Applications: Paint
thinner, adhesive remover, brush cleaner
Evaporation
Rate: Very Fast
Flash
Point: 60°F (16°C)
Flammability
Rating: Extremely Flammable
Exposure
Limits: OSHA PEL: None
VM&P Naphtha
For most applications,
either turpentine or mineral spirits are great choices for thinning oil-based
paints. When you are pressed for time, consider VM&P Naphtha. The VM&P
stands for “Varnish Manufacturing & Painters”. VM&P Naphtha evaporates much faster than
either turpentine or mineral spirits, which accelerates drying times.
Caveat
emptor: there are different types of naphtha are on the market.
They are not all the same thing. Some naphthas dry very slowly and will leave a
residue. That’s not what you want to buy. Instead, look for the product labeled
as VM&P Naphtha.
Safety
Note: VM&P Naphtha evaporates very quickly and is highly
flammable. Use responsibly. Work in a well-ventilated area of your shop. Wear
heavy-duty latex gloves, safety glasses and a respiratory mask.
Test,
Don’t Guess. Prior
to using VM&P Naphtha with your brand of enamel, test it for compatibility.
Applications: Paint
thinner (great for spray painting); brush cleaner
Evaporation
Rate: Fast
Flash
Point: 55°F (13°C)
Flammability
Rating: Highly Flammable
Exposure
Limits: OSHA PEL: None
Toluene
Toluene is used in many
paint thinners, cleaners and adhesives. It is also used in some adhesive
removers. Misused it is dangerous stuff. If you breathe enough of it, you will
get as high as a kite. The danger is that it can damage your central nervous
system, liver and kidneys.
If you are removing
graphics, I suggest using a safer adhesive remover than one with toluene. If you must use this solvent, do not use it in
a confined space. You need good ventilation and in some cases you should use an
air respirator.
Breathing its fumes is not
the only way that toluene can enter your system. You can also absorb it through
your skin. For this reason, you should use nitrile gloves when working with
adhesive removers or cleaners containing toluene.
Applications:
Ingredient
in adhesive removers
Evaporation
Rate: Fast
Flash
Point: 45°F (7°C)
Flammability
Rating: Flammable
Exposure
Limits: NIOSH REL: TWA 100 ppm (375 mg/m3). Toluene is the nasty
solvent in airplane glue that makes you high if you sniff it. Based on personal
experience, you can become intoxicated within 10 minutes of exposure from the
fumes of adhesive removers containing toluene. When working with anything
containing toluene, I would strongly recommend wearing an air respirator.
Wax & Grease Remover
For painting prep and
surface prep prior to vinyl application, wax and grease removers are essential.
The composition of solvent cleaners varies from one manufacturer to another.
Typical ingredients include mineral spirits, naphtha, heptane and toluene. Some
formulations are very aggressive, while others are mild.
Because ingredients vary
greatly, always read the safety data sheet (SDS) prior to use. To ensure you
don’t damage the paint system of a car or truck, test the solvent on an
inconspicuous area of the vehicle before using it.
Wax and grease removers are
comprised entirely of flammable solvents and typically have a flash point lower
than that of turpentine. When working with these solvent cleaners always wear
protective gloves, such as neoprene gloves, and wear safety glasses with side
shield. Work in a well ventilated shop when prepping a surface for painting or
vinyl application. For information on surface preparation prior to graphics
application read my story 3-Step Prep for Vehicle Graphics.
Xylene (Xylol)
When I was installing
vehicle graphics, I frequently used xylene as a cleaner for oily dirt. Many
decal installers do the same thing. Xylene is a very hazardous solvent and
should only be used with care. Protective gloves are a must.
Applications:
Surface prep
Evaporation
Rate: Fast
Flash
Point: 90°F (32°C)
Flammability
Rating: Flammable
Exposure
Limits: TWA 100 ppm (435 mg/m3)
Conclusion
Working with solvents is
unavoidable in painting. Some applications, such as spray painting and
substrate preparation, expose us to higher levels of solvent vapors. What’s
more, accidents, such as solvent spills, can and do happen. Proper education
and adherence to safety guidelines can
help us minimize the hazards. Your employees must have training covering the
solvents that they use and must have access to all pertinent information such
as Safety Data Sheets (SDS). By understanding the properties of the solvents
that you use, you can select the right solvent for the job as well as choose
the less toxic and less volatile alternatives available.
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Vinyl Application Videos
Squeegee Technique. Nothing is more basic in vinyl application than the squeegee. But some squeegees work better than others. And there are right ways and wrong ways to use this simple tool. This video clip reviews squeegee selection, squeegee care and squeegee technique. Click to Link
Wet Applications. Dry applications are typically recommended for most vinyl applications. For those exceptions to the rule, this instructional video explains the right way to perform a wet application. Click to Link
Application of Window Graphics. Installing vinyl graphics on glass can be challenging, because the adhesive aggressively grabs onto this high energy surface. Repositioning graphics on window is generally difficult, if not impossible. This instructional video explains how to dry apply window graphics right the first time. It also describes the necessary steps required for surface preparation. Click to Link
Transferring Frosted Window Graphics Films. Because frosted window films are highly textured, transferring cut vinyl graphics can be problematic. This video provides direction in selection of the right application tape and how to apply these films quickly, easily and without problems. Click to Link
3-Step Surface Prep. This instructional video describes how to properly clean the surface of a vehicle before applying pressure sensitive vinyl graphics to a trailer or doing a full wrap of a car or van. This three step surface prep involves detergent washing, solvent cleaning and a final wipe down with IPA. Click to Link
Vinyl Application Over Rivets. Applying vinyl graphics on vehicle surfaces with rivets is challenging for most sign makers. Vinyl failures to these surfaces are all too common. This video demonstrates some tips and procedures, used by professional decal installers, which will make these demanding applications easier and more trouble-free. Click to Link
Vinyl Application to Corrugations. Learn how to apply vinyl graphics to corrugations in a relaxed state. Forcing films into the valleys of corrugations puts too much mechanical stress on the film. Sooner or later, the vinyl will lift or tent in valleys. Click to Link
Applying Air Egress Vinyls. Vinyl films with air egress release liners have almost eliminated bubbles and wrinkles from applied graphics. Air egress release liners with their highly textured surface structure are problematic. Not much will stick to these liners other than the vinyl film. At RTape our best premask solution for air egress liners is a special Conform® tape called 4761RLA. Click to Link
About Jim Hingst: After fourteen years as Business Development Manager at RTape, Jim Hingst retired. He was involved in many facets of the company’s business, including marketing, sales, product development and technical service.
Hingst began his career 42 years ago in the graphic arts field creating and producing advertising and promotional materials for a large test equipment manufacturer. Working for offset printers, large format screen printers, vinyl film manufacturers, and application tape companies, his experience included estimating, production planning, purchasing and production art, as well as sales and marketing. In his capacity as a salesman, Hingst was recognized with numerous sales achievement awards.
Drawing on his experience in production and as graphics installation subcontractor, Hingst provided the industry with practical advice, publishing more than 150 articles for publications, such as Signs Canada, SignCraft, Signs of the Times, Screen Printing, Sign and Digital Graphics and Sign Builder Illustrated. He also posted more than 325 stories on his blog (hingstssignpost.blogspot.com). In 2007 Hingst’s book, Vinyl Sign Techniques, was published. Vinyl Sign Techniques is available at sign supply distributors and at Amazon.
© 2016 Jim Hingst
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