Dyes vs. Pigments Re-visited

There is a common misuse of the word “dye” in the leather repair and restoration business.  While I’ve discussed this before here, it’s time to address the issue again. 

There are two methods for coloring leather.  1. Dyes.  2. Dyes and then pigment coated.  It is very rare that leather would be pigment coated without having been dyed first.

Starting with the basics – Animal skins are tanned.  This process converts the skin to leather.  The main purpose of tanning is to preserve the hide.  It stops the natural degeneration or rotting process.  At the end of the tanning procedure and before the color step, the hide is called a “crust.”

The crust is highly absorbent. Think of a chemise. The crust is infused with a dye which we all know to be a coloring element.  The actual dye molecule is very small.  It penetrates into the fiber structure of the crust (leather) and establishes the color.  Typically it penetrates completely through the leather (struck through) so looking at a cross cut, you see the same color from front to back.  The dye is not molecularly bound to fiber structure, rather it as floating within the fiber bundles.  Because it is free floating, one of its attributes is migration.  It will transfer or move. 

Water will accelerate migration.  Consider blue jeans.  They fade when washed.  The dye molecule migrates out of the medium (in this case denim) and is flushed down the drain.  I have had occasion to witness this phenomena with leather many times.  A damp white cotton cloth wiped across dyed leather will pull the color.

Dyes have a unique beauty.  Because of their small molecular construct, dyes are translucent.  You look into the leather to see its color.  It accentuates the natural beauty of the leather. Because the porosity of leather is inconsistent, some areas of the hide will accept more dye than others.  This creates the natural mottling affect you see with dyed leather.  Its beauty can’t be beat.  We classify this leather as being “unfinished.”

There is a dark side.  The dye molecule does not tolerate UV light very well.  That wave length or spectrum of light hits the dye molecule and breaks it up.  This process gradually leaches the dye from leather causing the leather to lose its color (fade).  Furthermore, dyed leather continues to have a high level of porosity.  Spill a liquid and it will soak into the leather, potentially staining the leather.  In reality the stained area has been re-colored.  So trying to clean it is like trying to clean a tattoo from your skin.

Bottom line: dyed or unfinished leather is beautiful when new, but it is aesthetically vulnerable to staining and fading.  Only about 15% of all leather furniture is unfinished.  It is typically the most expensive leather as only the finest hides (least flawed with unsightly hide characteristics) can qualify to be unfinished.

Most leather then goes through a secondary coloring process with the application of a pigmented coating.  The pigment molecule sits on the leather’s surface.  As a coloring element the pigment molecule is a big, robust molecule with excellent covering power, like snow on the ground.  The pigment molecule is carried in a binding chemistry that locks it in place.  That binder chemistry is uniquely engineered for leather.  It establishes a film on the leather surface that is opaque.  The color you see is from a topical colorant that is a pigment.  This is known as “finished” leather.  

Pigments lack translucency so the color is flatter than dyes.  But pigments are far less sensitive to UV so they don’t fade nearly as radically.  Consider and automobile leather car seat. They don’t fade despite tons of sun exposure.  They are colored with a pigment.  Additionally, the film of color on the leather will resist absorption. If something spills, you can wipe it off the leather as it won’t immediately soak in.

You can not successfully re-dye leather using dye as the coloring element for a whole bunch of technical reasons, not the least of which is that you will be wearing the color on your clothing if you sit on the furniture.  Setting the dye so that it doesn’t transfer easily can only be done at a tannery under very specific and controlled processes.   

Leather can be re-colored, but only with a pigment application.  If it was dyed (unfinished) leather in the first place, the re-coloring process is with a pigment that provides full covering power, thus converting the leather to a “finished” or pigment coated status.

Of course we do this color restoration process professionally all the time, and it is the essence of the Do-It-Yourself kits offered by Advanced Leather Solutions.  Taking it one step further, because it’s an opaque chemistry, the color coating can be changed to whatever color desired.

The next time a leather technician says he/she can re-dye your leather, be weary as that person does not understand the fundamental difference between a dye and a pigment.

Copyright  2010, Kevin Gillan

Advanced Leather Solutions SG Series Marketing Info

The following is marketing information for those who wish to become resellers of the proven SG Series of leather performance products made by Advanced Leather Solutions, Inc.  Here at ADVLeather.com we chemically engineer the best performance  for leather care products.  Those who use the products praise the results.  Those who distribute the products to their customers report back to us that their customers are also praising the merits of SG - 5, our leather cleaner and SG - 25 our leather conditioner.  As a reader of my blog, you too can take advantage these superb products, either under your own private label or take advantage of the brand awareness Advanced Leather Solutions has already created.  Here are the details...

Advanced Leather Solutions --- The SG Series of Leather Performance products

Intensive cleaning and moisturizing for automobile, leather garments and furniture

Chemically engineered specifically for leather

Safe and easy cleaning action --- SG - 5 cleans automotive and upholstery grade leather.  The cleaning action is safe for leather, surrounding and lifting dirt away from the leather, even if deeply embedded in the grain pattern.  Because it is safe for leather, frequent repeated application will not damage the leather.  The cleaning action brightens the leather without the use of harsh bleaching agents. 

Intensive moisture replenishment ---   SG - 25 is an intensive moisturizer for automobile and upholstery.  These replenishing oils and other softening agents are absorbed deep into the leather, where they restore the leather’s vitality. 

Improves suppleness --- As leather dries, it loses its soft, supple feel.  The intensive moisturizing agents in SG – 25 bring back lost suppleness, prolonging the life of the leather even if exposed to harsh heat and intense sun.  

Restructures top layer --- SG – 25 actually restructures the protective top layer (top-coat) to your leather.  Through use and sun exposure, this top layer loses its effectiveness.  It can even feel rough or chaffed to the touch.  The SG Series restructures this protective layer improving the long term wear characteristics.  Repeated use of the SG products builds this protective layer adding durability to your leather.  It leaves even old, dried leather feeling silky smooth.

pH balance --  The SG Series  is pH balanced.  Leather is acidic at 4.5 to 5.0.  Most leather cleaners are alkaline. This means they are actually harming the leather. When Leather’s pH is out of balance, it accelerates the breakdown its internal fibrous structure. The SG Series of Leather Performance products brings the leather back to its appropriate pH, reducing the long term damage to the leather caused by inappropriate pH leather care products.

Anti-bacteria and virus Agent Added – Pets and kids are germ factories.  SG – 25 not only conditions and protects your leather, it also adds anti-bacteria and virus protection.  With the system, when we say clean, we mean hospital clean.

Easy wipe on and rub --- Easy to apply with a simple, cleaning and conditioning wipe and rub technique.  No more cleaners that dull leather.  No more conditioners that make the leather feel sticky or oily.

 Long term effectiveness --- The SG Series of Leather Performance ingredients have staying power, reducing the frequency of application required.  Even after a single application your leather will feel better, last longer and give you the overall performance expected from leather in high-end automobiles.

The warmer the better --- The warmer the environment, the better SG – 25 performs.  When leather is warm, the moisturizing agents quickly revitalize the leather.  Even old, dried, tired looking leather can be brought back to life.

Suggested Marketing Channels

SG – Series of Leather Performance Products is an after-market product targeted to automobile and furniture owners who want to protect their investment in leather.  It will also work on a wide variety of other leather goods like jackets, motorcycle leather seats, saddlebags, briefcases, shoes, etc.

Example channels should include the following:

1. Auto Dealerships (new and used)
2. Aftermarket auto supply stores (Pep boys, etc.)
3. Auto paint shops (Earl Schibb, etc.)
4. Auto detailer
5. Car washers
6. Auto clubs
7. Large chain stores
8. Furniture retailers
9. Direct sales via advertising in auto trader, etc.
10. Direct sales via internet
11. Flea market booths

Additional considerations:

It can be used for horse tack leather as well.

Targeted demographic markets include middle to high income households and auto owners who care about their leather.

Suggested Sales and General Awareness Tactics

1. Create an article for publication in a trade journal.  Focus on uniqueness.  Examples available for ADVleather.com
2. Make up 1 or 2 oz samples and distribute through above channels – try it, you’ll like it approach.
3. Create point-of-sale displays again emphasizing uniqueness of product offering.
4. Direct sales to each of the above listed sales channels.

Bottle and Label Considerations

We recommend HDPE cylinder rounds, natural. These are semi-clear plastic bottles so you can see the contents.  Use a poly-tops white closure with a flip top for ease of use.  Make sure the ink on the label is not susceptible to having the ink run when it gets wet.

Copyright 2010, Kevin Gillan

Leather Care for Automobile Grade Leather

I'm often asked: "What can I do to prolong the life of my automobile leather?"

To understand the effectiveness of leather care products, you should first get a solid grounding on the properties of automobile grade leather.

Here are the issues that must be considered.

1. Automobile grade leather is typically low to mid grade. (I use the word 'grade' here to define the long term durability characteristics.) This is true across the board regardless of brand name. The few exceptions are custom installs, and very high end like Rolls, Ferrari or Lamborghini.

2. The leather is generally a 'corrected' top grain where the word corrected means sanded. At a tannery hides are sorted based on a variety of characteristics. Commonly, hides that are heavily marked with range marks (barb wire scars, bug bites, brand scars, urine burns - a cow will lay in its own urine, etc.), are not fit for high end application due to the unsightly nature of these anomalies. These hides have the epidermis sanded down to eliminate or significantly minimize the scaring.

3. As a skin grows from the flesh side to the out side, it develops layers, gradually building very tight and tough fiber bundles that end up as the epidermis. The epidermis is what classically provides leather's durability and ranges in thickness and toughness based on where on the animal you measure. For example across the top shoulders and down the backbone ridge you'll find the thickest and most durable epidermal tissue. (Natures way of protecting the animal from predators). So the epidermis ranges from 0.2 mm to 1.5 mm in thickness.

4. When you 'correct' the hide by sanding the epidermis you are removing the unsightly characteristics but you are also compromising durability to the degree that you sand away epidermal toughness.

5. To counter this reduction in durability, the corrected top grain hide destined for an automobile application is processed with a coloring strategy that uses a tough resin as the binding agent of the pigment color coating, and an even tougher resin for the clear top-coat. Both the color and top-coat are applied heavily, covering over and concealing any remaining hide scars. The resin is typically a urethane derivative of some kind. While the resin imparts toughness, it also stiffens the feel. So you compromise tactile presentation for the benefit of wear resistance. In an automobile, the feel of the leather is not as important as in home furnishings.

6. Please note that leather is acidic on the pH scale. It runs between 4.5 and 5.0. If you expose automobile leather to harsh cleaners or conditioners that are not pH balanced, you are accelerating the demise of the leather. You may think you are helping prolong the life of the leather, but if you expose leather to inappropriate chemicals you are in fact accelerating the demise of leather.

7. When leather is processed at a tannery, it is infused with moisture (natural oils) that promote flexibility and suppleness. This moisture represents about 25% of the mass of leather. When exposed to heat, the moisture content gradually evaporates, stiffening and shrinking the leather. Examine the headrest in the backseat. This leather is exposed to intense sun through the back window. If the car has any age on it, generally you can detect a significant stiffening due to moisture loss.

8. Finally the wear patterns in a car are different than in a home. The driver slides across the seat as they enter and exit creating abrasion wear, gradually eroding the top-coat, and eventually wearing through and into the color coat. Once the top coat is compromised, the color coat will erode quickly, exposing raw leather. Additionally, look at the wear pattern of the driver's seat. Notice the crease lines in the seat bolster panel (driver's side door). These are created by the "torqueing" action on the leather of entry into the vehicle. The leather is being pulled and stretched by the weight and movement of the person entering and dragging their body weight across that panel, thus creating the creasing. These crease lines eventually develop into cracks which means the demise of the leather.

All of this is important background information to understand the characteristics of the best leather care products for an automobile application. The chemical construct of http://www.advleather.com/ products take all of this into consideration. For example, SG - 5 is an excellent cleaner that has been pH balanced for leather, thus is safe to use. It actually helps correct pH which then avoids fiber brake down. SG - 25 and SG - 50 are conditioners to which resins have been added. This is a combination of moisturizing agents (conditioner) and protection. While the conditioner component instills lost moisture, the resin re-builds lost top-coat, therefore prolonging the life of the leather by increasing its wear resistance. The combination of conditioner and resin also imparts a silky hand or feel to the leather and tends to brighten dull leather by boosting its reflective value.

With the right products and a little bit of care, you can dramatically improve the life of your automobile leather. The SG series of leather care are all chemically engineered with these facts in mind.

copyright 2009, Kevin Gillan