Silicone (Si, 28.086 amu), the 14th element on the periodic table, is often used in sealants, lubricants, fillers, and medicines for its ability to polymerize (or form long chains of repeating units) with oxygen.


More accurately referred to as polymerized siloxanes or polysiloxanes, these polymers have a silicon-oxygen backbone chain. These chains are tetravalent (4 bonds) and allow for the addition of side groups that promote cross-linking between each individual chain.


There are many useful applications to polysiloxanes owed to their low thermal conductivity, low reactivity, low toxicity, resistance to UV light, and ability to prevent microbiological growth.


Hey! I made a free course with a 10-minute video lecture on this topic. Figured it’d make reading all this science stuff more visual and fun! Click here to access.


The greatest use in terms of smear-resistant cosmetics is their ability to repel water. This hydrophobic (fear of water) nature and ability to cross-link is by-and-large the root of LipSense’s all day staying power.

An Analysis of Patent #1: Silicone Grafted Thermoplastic Elastomeric Copolymers

“The copolymers of the present invention are characterized in having an elastomeric  or flexible backbone…”

This patent describes how the inventors used tetravalent polysiloxane to incorporate favorable “R groups” (these are side chains or little add-ons to the chain’s backbone) that promote elasticity, provide thermal resistance, incorporate gentle bonding agents, and allow for all-day wear.


Various Polysiloxane Configurations


These polymers exhibit two distinct immiscible phases: alcohol suspension & activation.

Phase 1: Polysiloxane suspended in alcohol – The polymer remains suspended in the Denatured SD-40 Alcohol* until applied evenly across the skin. At that point, the alcohol** evaporates.

Phase 2: Activation – The evaporation of the alcohol allows the polysiloxane to begin and set into the molecular bonding process and promotes cross-linking to establish a thermodynamically favorable rearrangement.

Furthermore, these polysiloxanes have been formulated to uniformly spread upon the skin, feel soft to the touch, and allow for substantial coverage. The polymer is UV resistant, owing to its strong bonding pattern and protective layering over the skin.

An Analysis of Patent #2: Thermoplastic Elastomeric Copolymers

Very similar to their first patent, Drs. Torgerson and Midha released their preliminary findings back in 1998 on the new substance and proposed its usefulness in cosmetics. An interesting read if you’d like to know more about the development of Patent #1.

The patent discusses the infinite possibilities of incorporated R-groups to the polysiloxane change and mentions “acrylic acid” salt derivation. This allows the company to protect against an enormous amount of small alterations that could result in a similar product (AKA: Job Security).


Octylacrylamide Copolymer


A relevant difference between the two involves the mention of the octylacrylamide copolymer. This polymer is a cross-linking agent that works as an R-group of the polysiloxane chain to promote the a hydrophobic nature owing to LipSenses no smudge, no going to stain your coffee mug, kiss your baby all you want, leave no trace properties.

An Analysis of Patent #3: Smear-Resistant Cosmetic

Did you know many of the ingredients that formulate LipSense came original from hair spray and hair conditioners? This patent describes the trademark components of LipSense: AMPHOMER, GANTREZ, GAF. QUADAMER, etc. that synergize to form LipSense’s holding power. It’s incredible how deep these patents and their associated research goes! Someone could make a dissertation entirely from the science behind LipSense (hmm…).

“It binds and seals the cosmetic to the lips in a clear, sheer film which does not crack or cake”.

These components primarily function as a transparent, breathable sealer. This is THE PATENT that firmly establishes the claim that senegence contains NO WAXES or PETROLEUM PRODUCTS.


It also addresses how products that do contain wax or petroleum will smear, burn, and dry the lips in addition to break down the molecular film created by LipSense. Really, I cannot put it in better wording than this summary of the patent. They did an amazing job writing this one: 

The cosmetic of the invention contains no waxes or petroleum products. Waxes can smear while petroleum products can burn or dry the lips. The cosmetic of the invention is so sheer that a wearer can layer on at least three different layers without any danger of the product caking up on the lips. Indeed, the different layers of the cosmetic of the invention can be applied in different colors to achieve a unique, aesthetic effect.

Also, a different number of layers of the cosmetic can be applied to produce different aesthetic appearances. A single layer of the preferred embodiment of the cosmetic of the invention dries to a sheer finish. If a second layer of the cosmetic is applied over the first, a medium matte finish is achieved. By applying a third layer, a wearer achieves a full cover matte finish. Even with use of multiple layers, however, the cosmetic of the invention will not cake or smear.

The cosmetic of the invention can be formulated in any number of different colors by varying the color of the pigment employed. The cosmetic of the invention is in a liquid form when applied and the colors can be used individually or mixed by layering to create an unlimited array of custom, personalized colors. Each layer takes about twenty seconds to dry from the time of application.

In addition to its basic components, the cosmetic of the invention may include other substances to achieve certain effects. For example, the cosmetic may be formulated with at least one part of a dimethicone component to achieve a gloss or satin effect. Although the cosmetic formulated in this manner looks and feels viscid or sticky, it will not come off, but will stay on the lips despite extended wear and exposure to moisture.

The cosmetic of the invention provides natural sun protection and keeps the lips from chapping, indoors or outdoors, in both cold and hot weather. It will not stick to teeth or dental braces. Unlike a user wearing lipstick, an individual wearing the cosmetic of the present invention can actually brush and floss after means without smearing the cosmetic or reducing the thickness of its lip coating, and without having to reapply the lip covering.

The cosmetic of the invention is organic and hypoallergenic. Unless a flavor or fragrance is added, it is also odor free and contains no petroleum products.

The cosmetic of the invention enhances the beauty of the wearer without surgery by filling in the inner lips where conventional lipstick will not stay. The cosmetic of the invention is extremely sheer and is not gooey like conventional lipstick. Even after three or more layers of the cosmetic of the invention are applied, the lips still feel bare and have a perfect matte finish.

The cosmetic of the invention will not come off with petroleum jelly or cleansing cream. Due to its permanence, care must be taken not to spill the cosmetic of the invention in liquid form onto clothing or other fabrics. However, if the cosmetic is accidentally spilled onto carpeting or clothing, it can be readily removed by applying water and then applying isopropyl alcohol or the cosmetic removing formulations described below, provided that cleanup is undertaken promptly.

 I hope you enjoyed this overview of the patents behind the development of LipSense® by SeneGence®. Please feel free to join Nerdy for My SeneSisters, a Facebook group dedicated to scientific conversations about the product. BYEEEE!





  1. (Patent 1) Torgerson, Peter Marte, and Sanjeev Midha. Silicone grafted thermoplastic elastomeric copolymers and hair and skin care compositions containing the same. The Procter & Gamble Company, assignee. Patent US 6537532 B1. 25 Mar. 2003. URL:
  2. (Patent 2) Torgerson, Peter Marte, and Sanjeev Midha. Thermoplastic elastomeric copolymers used in hair and skin care compositions. The Procter & Gamble Company, assignee. Patent US 5730966 A. 24 Mar. 1998. URL:
  3. (Patent 3) Nichols, Rosemarie, and Martin J. Weisman, assignee. Smear-resistance cosmetic. Patent US 6509009 B2. 21, Jan. 2003. URL:

Footnotes (*):

*To learn more about the individual ingredients found in LipSense, click here.

**Notice how the alcohol never enters the system of the wearer, an important note for those who are confused about its toxicity after a simple google search. Note that this substance is only toxic if consumed in great quantities. No drinky, no sicky!