Cosmetology: Chemical Texture Services

Comprehensive vocabulary flashcards covering Chapter 15: Chemical Texture Services, including chemical relaxers, permanent waving, rod types, wrap patterns, and safety precautions.

Chemical texture services

Hair services that either cause a change within the hair’s natural wave or curl pattern, or smooth the cuticle.

Chemical hair relaxing

A process that permanently rearranges curly hair’s structure into a straighter or smoother form.

Keratin-based smoothing treatments

Semipermanent smoothing treatments (also known as Brazilian keratin treatments) that coat the cuticle in a protective protein layer, eliminating frizz and up to 90 percent of curl for up to 12 weeks (or up to three months).

Permanent waving

A two-step process to create body, wave, or curl in the hair by wrapping hair on perm rods and altering it with permanent wave solution and neutralizer.

Soft curl permanent

A chemical service that loosens very curly hair, leaving it with soft curls or waves to permanently rearrange coils to a looser curl pattern.

Hydrogen bonds

Physical side bonds that are broken when hair is wet and naturally reform as the hair dries.

Disulfide bonds

Chemical side bonds consisting of two bonded sulfur atoms that cannot be broken by water and require chemical solutions to break and create a permanent change in hair texture.

Lanthionization

The process by which hydroxide relaxers permanently straighten hair by removing one sulfur atom from a disulfide bond and converting it into a lanthionine bond.

Lanthionine bond

A bond containing only one sulfur atom that is formed when a hydroxide relaxer breaks a disulfide bond; it can never be reformed.

Metal hydroxide relaxers

Ionic compounds formed by a metal combined with oxygen and hydrogen—including sodium hydroxide ($NaOH$), potassium hydroxide ($KOH$), and lithium hydroxide ($LiOH$)—that require no product mixing before application.

Sodium hydroxide relaxers

Commonly known as lye relaxers, these are the oldest and most common professional relaxers; they feature a $\text{pH}$ of $12.5\text{--}14.0$ and process rapidly without mixing.

No-lye relaxers

Hydroxide relaxers formulated with lithium hydroxide, potassium hydroxide, or guanidine hydroxide (usually with a $\text{pH}$ of $9.0\text{--}11.0$) that cause less skin irritation than lye relaxers but can dry hair via calcium buildup.

Base cream

An oily cream (protective base cream) used to protect the client's skin and scalp from chemical irritation during a relaxer service.

Base relaxers

Hydroxide relaxers that require a separate prior application of protective base cream to the entire scalp, hairline, nape, and ears.

No-base relaxers

Hydroxide relaxers formulated with a protective base that melts at body temperature and settles out onto the scalp as a thin, protective coating during application.

Hydroxide neutralization

An acid–alkali neutralization reaction that deactivates alkaline relaxer residues left in the hair and acidifies the hair and scalp back to their normal $\text{pH}$.

Ammonium thioglycolate (ATG)

A compound that serves as the active reducing agent in thio relaxers and alkaline permanent waves.

Viscosity

The measurement of a liquid’s thickness or thinness that affects its fluid flow properties.

Japanese thermal straightening

A specialty service (also called thermal reconditioning or TR) that combines a thio relaxer solution with flat ironing to permanently straighten hair.

Thio neutralization

An oxidation process that deactivates thio relaxer or perm residue and rebuilds disulfide bonds by removing added hydrogen atoms.

Patch test

A required test (also known as a predisposition test) performed 24 to 48 hours before a chemical service to identify any client allergies or sensitivities to the product.

Metallic salts test

A safety test mixing 1 ounce ($29.5\,\text{mL}$) of 20-volume peroxide with 20 drops of 28 percent ammonia to detect metallic compounds in hair that are chemically incompatible with perms or relaxers.

Porosity

The condition of the cuticle layer and its ability to absorb and retain moisture, determined by the degree to which cuticle scales are raised.

Elasticity

The hair's ability to stretch and return to its original length without breaking, reflecting the strength of side bonds in the cortex.

Central centrifugal cicatricial alopecia (C.C.C.A.)

A form of scarring alopecia resulting in permanent hair loss, presenting with symptoms such as burning, tingling, tenderness, crusting, or inflammation.

Virgin relaxer

A chemical relaxer application on hair that has never received relaxing chemicals, starting on the midshaft $0.5\,\text{inch}$ away from the scalp up to the ends.

Relaxer retouch

A chemical relaxing application applied strictly to the new growth area, starting $0.25$ to $0.5\,\text{inch}$ from the scalp.

Alkaline waves

Permanent waves (also known as cold waves) formulated with ammonium thioglycolate (ATG) at a $\text{pH}$ of $9.0\text{--}9.6$ that process at room temperature without added heat.

Glyceryl monothioglycolate (GMTG)

The primary active reducing agent found in true acid and acid-balanced permanent wave solutions.

True acid waves

Permanent waves with a $\text{pH}$ of $4.5\text{--}7.0$ that require an external heat source (endothermic) to process and produce a softer curl than alkaline waves.

Acid-balanced waves

Permanent waves formulated with GMTG that have a neutral $\text{pH}$ around $7.0$ (or $7.8\text{--}8.2$), processing at room temperature without dryer heat to produce firmer curls than true acid waves.

Exothermic waves

Permanent waves that generate their own heat through an exothermic chemical reaction when an oxidizing agent (activator) is mixed with the perm solution.

Endothermic waves

Permanent waves activated by an outside heat source, typically an electric hooded dryer.

Ammonia-free waves

Perms that use alkanolamines such as aminomethyl propanol (AMP) or monoethanolamine (MEA) instead of ammonia to minimize odor.

Thio-free waves

Permanent waves that use reducing agents other than ATG, such as cysteamine or mercaptamine.

Concave rods

The most common perm rods, featuring a smaller diameter in the center and larger diameter on the ends, producing a tighter center curl and looser side curls.

Straight rods

Perm rods that are equal in diameter along their entire length, producing a uniform curl across the subsection width.

Soft bender rods

Flexible foam rods about $12\,\text{inches}$ ($30.5\,\text{cm}$) long with an internal wire that bend into shapes to create hybrid beach waves and textured curls.

Loop rods

Flexible circular rods (also called circle rods) about $12\,\text{inches}$ ($30.5\,\text{cm}$) long that fasten end-to-end to form a loop.

End papers

Thin, absorbent papers (end wraps) placed over hair ends to prevent fishhooks and smoothly control strands during rod winding.

Double flat wrap

An end paper technique in which one paper is placed under and another over the hair subsection, extending beyond the ends for maximum control.

Single flat wrap

An end paper technique using only one paper placed directly over the top of the hair subsection.

Bookend wrap

An end paper method using a single end paper folded in half over the ends of the hair subsection.

Base placement

The position of a perm rod in relation to its base section, determined by the angle at which the hair is wrapped (on-base, half off-base, or off-base).

Croquignole wrap

A perm wrap technique where hair is wound from ends toward the scalp in overlapping concentric layers, producing a tighter curl at the ends and larger curl near the scalp.

Spiral wrap

A perm wrapping technique where hair is wound vertically around a rod like stripes on a candy cane, creating uniform curl diameter from scalp to ends.

Basic perm wrap

A wrapping pattern (also known as a straight set wrap) where all rods within a panel move in the same direction on horizontal bases equal to the length and width of the rod.

Bricklay perm wrap

A wrapping pattern in which base sections are offset row by row (like bricks) to prevent noticeable splits and seamlessly blend hair flow.

Double-rod wrap

A wrap for extra-long hair (also known as a piggyback wrap) where hair is wrapped on one rod from scalp to midshaft and on a second rod for the remaining ends.