Permanent hair straightening solves your daily battle with unruly curls or persistent frizz. Waking up to effortlessly smooth hair, resistant to the whims of humidity or weather, contributes significantly to its popularity.

It is important to understand the process of permanent hair straightening and, well, the underlying hows of it, so you can make informed decisions when you’re considering such treatment.

This guide will look into the science behind permanent hair straightening, its types, how each works, pre-treatment considerations, and aftercare.

Let’s get right into it!


The Science Behind Permanent Hair Straightening

The diameter of our hair can be compared to a thread and yet it has three layers! The hair structure, no matter the type, can be broadly categorized into three layers: the cuticle, cortex, and medulla.

  1. Cuticle: Serving as the outermost protective layer, the cuticle consists of overlapping, scale-like structures. Its primary role is to shield the inner layers from external factors, such as UV rays and environmental pollutants.
  2. Cortex: Situated beneath the cuticle, the cortex is the thickest layer and contains keratin, the protein responsible for hair strength and elasticity. The cortex largely dictates the hair’s color, texture, and overall integrity.
  3. Medulla: While not present in all hair types, the medulla is the innermost layer. Its function remains less clear, and its absence does not compromise the overall health or appearance of the hair.

hair structure layers Permanent Hair Straightening: A Comprehensive Guide

Two primary types of bonds play pivotal roles: disulfide bonds and hydrogen bonds.

Disulfide bonds are the strong chemical links that connect the protein chains within the cortex. These bonds are responsible for holding together keratin. The natural shape and structure of the hair, whether it be straight, wavy, or curly, is also on these bonds.

On the other hand, hydrogen bonds are weaker and they form between the water molecules in the hair. These bonds are responsible for the temporary changes in the hair’s structure in response to external factors like water, humidity, or styling.

How does it work?

Now, permanent hair straightening works by applying chemical processes to your hair that will break and restructure your hair bonds to get you that sleek, straight hair.

Many permanent hair straightening treatments use alkaline solutions. These solutions often contain chemicals like ammonium thioglycolate and sodium hydroxide (the former is safer than the latter though). Together with heat application, the protein structure of hair is altered to be straight.

Other ingredients in straightening products, though not in every one of them, are formaldehyde, sodium hydroxide, parabens, cyclosiloxanes, diethanolamine, phthalates, benzophenone-3, and triclosan. Each component contributes to the efficacy and safety of the treatment but these chemicals have “a hazard trait and/or an environmental or toxicological endpoint” (Department of Toxic Substances Control, 2021).

You better be careful then. It is given that salons are knowledgeable and careful when it comes to chemicals as such, but you still must conduct your research and consult with your stylist to have your concerns addressed.


Types of Permanent Hair Straightening

Japanese Hair Straightening (Thermal Reconditioning)

Japanese Hair Straightening provides semi-permanent to permanent results. The result is a smooth, pin-straight finish that lasts even in humid conditions.

At Christopher Hanna, its application process takes more or less 4 hours, ultimately depending on the hair’s length, thickness, and texture.

Brazilian Keratin Treatment

A Brazilian Keratin Treatment effectively reduces frizz and adds shine to the hair. The smoothing effect gradually diminishes with each wash, necessitating periodic treatments.

! Some formulations contain formaldehyde or similar chemicals.

At Christopher Hanna, the Keratin Treatment process typically takes 90 to 180 minutes, making it a relatively quicker alternative compared to some other permanent straightening methods.

Find out if your hair type is safe for a keratin treatment.

Chemical Hair Straightening (Hair Rebonding)

Chemical hair straightening offers long-lasting, often permanent, straightening effects. The term “Rebonding” signifies the subsequent step of reforming these bonds in a new configuration. Its outcome is more predictable and manageable with consistent straightness.

On average, it may take anywhere from 3 to 6 hours to complete the entire procedure. That may be a lot of time but it sure is a rewarding investment.


Permanent Hair Straightening After Care and Maintenance

Congratulations on achieving that sleek, straight look with permanent hair straightening! Now, we deal with aftercare and maintenance to ensure your straightened hair stays stunning for the long haul.


First and foremost,

the first cardinal rule of [permanent hair straightening] maintenance is that you’re forbidden to wet your hair for [24 to 72 hours] after getting a [hair straightening treatment] at the risk of deactivating the ammonium thioglycolate.

– Reese Witherspoon as Elle Woods on Legally Blonde (2001)


While you’re at it, sleep on silk or satin pillowcases to reduce friction, avoiding frizz and breakage.


Once past that phase, wash your hair using sulfate-free shampoos especially if you have a sensitive scalp and your hair tends to be dry to gently cleanse your hair without stripping away essential moisture. Ensure that every product you use by then is meant for chemically treated hair. You wouldn’t want your hair to come back to how it was before the treatment.


That said, moisturize regularly. Invest in quality conditioners and leave-in treatments to keep your hair well-moisturized. Look for products with hydrating ingredients like glycerin, hyaluronic acid, or keratin to maintain the health of your straightened strands.


Maintaining that sleek hair does not mean heating it all over again frequently. You must avoid heat overload. While heat styling tools can be your allies, excessive heat can lead to damage over time. Use a heat protectant before styling and aim for moderate temperatures to protect the integrity of your straightened hair. Also, use products with UV protection when exposed to the sun.


All those products and your hair is still somehow dry (it is how it is with chemical treatments). Get regular trims to prevent split ends and maintain the sleek appearance of your straightened hair. Trimming every 6-8 weeks helps keep the ends healthy and prevents breakage.


All that info and tips, and yet you still have to consult your stylist. They know your hair, or all things hair, perhaps even better than you do. They can assess the health of your straightened hair, recommend personalized products, and guide you on maintaining your specific style.


Importance of professional application for permanent hair straightening: Meet Christopher Hanna

Professional stylists are trained to apply straightening products with precision, minimizing the risk of uneven results or damage. They can accurately determine the optimal processing time for your specific hair type, preventing overexposure to chemicals.

As they have in-depth knowledge of various formulations, they can ensure a personalized approach to minimize potential risks, achieving the desired results without compromising hair health.

With that, meet Christopher Hanna.

At Christopher Hanna, you’ll find a team of experts dedicated to providing personalized and professional guidance on all aspects of permanent hair straightening services. Their commitment to excellence and client satisfaction makes them a trusted resource for achieving your desired sleek and straightened look.

Book your appointment now and get that sleek, manageable hair!