Contents

Consumer Products Industry
The Practical Guide to Surface Science (2026)

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Written by
Dr Amit Pratap Singh
PhD, Delhi University Post Doc - AIST Japan
Guest Author
Read More
alidad
Reviewed by
Dr Alidad Amirfazli
Dr. Amirfazli, a leading expert in surface wetting and superhydrophobic coatings, has 250+ publications, edits Advances in Colloid and Interface Science, and has received multiple research awards.
Scientific Advisor & Co-founder
Read More
D54c15105cfe94f786c500e4091d6ea65457608fde49ba183c8f862814a54249?s=100&d=m
Written By

Dr Amit Pratap Singh

Guest Author

PhD, Delhi University

Post Doc - AIST Japan

alidad
Reviewed By

Dr Alidad Amirfazli

Scientific Advisor & Co-founder

Dr. Amirfazli, a leading expert in surface wetting and superhydrophobic coatings, has 250+ publications, edits Advances in Colloid and Interface Science, and has received multiple research awards.

This is a practical guide to Surface Science for researchers working in the Consumer Products Industry.

In this all-new guide you’ll learn all about:

  • Crucial surface science principles
  • The significance of surface science measurements for the Consumer Products industry
  • Applicable ASTM Standards & Guidelines

Let’s dive right in.

Colorful showcase in cosmetic market

Executive Summary

What it covers: How consumer product teams use contact angle, sliding angle and surface free energy on coatings, adhesives, packaging, eyewear and sports goods. Each topic links to a use case, a standard or a published client study.
Key insights: High water repellency and easy roll off are different properties, and one contact angle will not tell you which you have. A coating can also fail by wearing away or by getting dirty, and a reading after cleaning tells the two apart.
Business value: A number for repellency, anti fog or surface energy lets teams rank formulations and catch drift between batches. One portable kit covers contact angle, sliding angle and surface tension, so a product lab can screen without booking an outside instrument.
Standards to follow: ISO 19403-7 describes roll off angle on a tilt stage for easy clean and anti adherent surfaces. ISO 27448 uses water contact angle under UV light to judge photocatalytic self cleaning coatings. Cite the edition your quality system uses.
Bottom line: Measure contact angle for how strongly a surface repels water, and sliding angle for whether drops run off. Start with the product claim you need to support, then book a 15 minute demo with your own samples.

Chapter 1: Introduction

In consumer products, many complaints start at a surface. A water repellent coating that wears off, goggles that fog, or a screen protector that lifts all come back to how liquids and adhesives wet a surface. These failures often show up only after the product is in use.

These are the places where wetting decides yield in consumer products work:

  • Water repellent and easy clean coatings. Contact angle and sliding angle, read as found and after cleaning, separate a worn coating from a dirty one. See hydrophobic coating performance verification.
  • Anti fog lenses and visors. Water contact angle before and after washing and abrasion tracks how long an anti fog coating keeps working. See anti fog coating validation.
  • PFAS free reformulation. Water and oil contact angles show whether a replacement chemistry still repels both liquids. See PFAS free reformulation.
  • Self cleaning surfaces. Contact angle, hysteresis and sliding angle show whether a surface sheds water and dirt. See self cleaning and anti soiling validation.
  • Ski and snowboard wax. Contact angle and sliding angle on the waxed base screen fluorine free waxes before snow tests. See ski wax hydrophobicity testing.

The Dropometer drop shape analysis kit measures contact angle, surface and interfacial tension, surface free energy and sliding angle with one portable setup. Its method was validated against a KRUSS DSA100E in two peer reviewed papers. If you are new to the terms, start with wettability.

We use the following surface properties to understand the behavior of Consumer Products products and improve their quality.

Chapter 2: Contact Angle Measurement

The contact angle quantifies the wettability of a surface by representing the angle between a liquid’s surface and a solid surface.
Dropletlab Research

Sample Image taken from Droplet Lab Tensiometer.

Young – Laplace Method

Polynomial Method

Dynamic Contact Angle

Ideally, when we place a drop on a solid surface, a unique angle exists between the liquid and the solid surface. We can calculate the value of this ideal contact angle (the so-called Young’s contact angle) using Young’s equation. In practice, due to surface geometry, roughness, heterogeneity, contamination, and deformation, the contact angle value on a surface is not necessarily a single consistent value but rather falls within a range. The upper and lower limits of this range are known as the advancing and receding contact angles, respectively. The values of advancing and receding contact angles for a solid surface are highly sensitive to many parameters, such as temperature, humidity, homogeneity, and minor contamination of the surface and liquid. For example, the advancing and receding contact angles of a surface can differ at different locations.

Dynamic Contact Angle versus Static Contact Angle

Practical surfaces and coatings naturally show contact angle hysteresis, indicating a range of equilibrium values. When we measure static contact angles, we get a single value within this range. Solely relying on static measurements poses problems, like poor repeatability and incomplete surface assessment regarding adhesion, cleanliness, roughness, and homogeneity.

In practical applications, we need to understand how easily a liquid spreads (advancing angle) and how easily it is removed (receding angle), such as in painting and cleaning. Measuring advancing and receding angles offers a holistic view of liquid-solid interaction, unlike static measurements, which yield an arbitrary value within the range.

This insight is crucial for real-world surfaces with variations, roughness, and dynamics, aiding industries like cosmetics, materials science, and biotechnology in designing effective surfaces and optimizing processes.

Learn how Contact Angle measurement is done on our Tensiometer

For a more complete understanding of Contact Angle measurement, read our Contact Angle measurement: The Definitive Guide

Open Benchmark Data: Contact Angle & Surface Energy

These reference measurements show how deionized water wets four standard substrates measured with the Droplet Lab Dropometer. Use them as visual and numerical benchmarks when you're checking your own sample preparation, treatments, and chemistry.

Full contact angle and surface energy datasets (including additional liquids and statistics) are available on our dataset hub.

Glass - DI Water
Glass - DI Water
Nylon - DI Water
Nylon - DI Water
PMMA - DI Water
PMMA - DI Water
Teflon - DI Water
Teflon - DI Water

The droplet images above are taken from the same benchmark series as our open dataset. For each substrate and probe liquid we report:

● Advancing and receding contact angles (and hysteresis)
● Derived surface energy (SFE) values based on multi-liquid measurements
● Measurement conditions, uncertainties, and sample preparation details

Comparing your own droplet shapes and angles against these references is a fast way to spot contamination, treatment drift, or unexpected changes in wettability.

Chapter 3: Surface Tension Measurement

This property measures the force that acts on the surface of a liquid, aiming to minimize its surface area.

Surface Tension Measurement

Sample Image taken from Droplet Lab Tensiometer

Dynamic Surface Tension

Dynamic surface tension differs from static surface tension, which refers to the surface energy per unit area (or force acting per unit length along the edge of a liquid surface).

Static surface tension characterizes the equilibrium state of the liquid interface, while dynamic surface tension accounts for the kinetics of changes at the interface. These changes could involve the presence of surfactants, additives, or variations in temperature, pressure, and composition at the interface.

When to use Dynamic Surface Tension Measurement

Dynamic surface tension is essential for processes that involve rapid changes at the liquid-gas or liquid-liquid interface, such as droplet and bubble formation, coalescence (change in surface area), the behavior of foams, and the drying of paints (change in composition, e.g., evaporation of solvent). It is measured by analyzing the shape of a hanging droplet over time.

Dynamic surface tension applies to various industries, including cosmetics, coatings, pharmaceuticals, paint, food and beverage, and industrial processes, where understanding and controlling the behavior of liquid interfaces is essential for product quality and process efficiency.

Learn how Surface Tension measurement is done on our Tensiometer

For a more complete understanding of Surface Energy measurement, read our Surface Tension measurement: The Definitive Guide

Chapter 4: Surface Energy Measurement

Surface energy refers to the energy required to create a unit area of a new surface.
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Sample Image taken from Droplet Lab Tensiometer

Learn how Surface Energy measurement is done on our Tensiometer

For a more complete understanding of Surface Energy measurement, read our Surface Energy measurement: The Definitive Guide

For benchmark contact angle and surface energy values on glass, nylon, PMMA, and Teflon, see the Open Benchmark Data panel above or visit our Dataset Hub for full CSV downloads.

Chapter 5: Sliding Angle Measurement

The sliding angle measures the angle at which a liquid film slides over a solid surface. It is commonly employed to assess the slip resistance of a surface.

sliding angle 1

Sample Image taken from Droplet Lab Tensiometer

Learn how Sliding Angle measurement is done on our Tensiometer

For a more complete understanding of Sliding Angle measurement, read our Sliding Angle Measurement: The Definitive Guide

Chapter 6: Real-World Applications

Within the Consumer Products industry, several case studies exemplify the advantages of conducting surface property measurements.

Bio-Based Ski Wax Prototype Development: Hydrophobicity, Hardness, Biodegradation and Glide Performance on Snow

This report describes the development of bio-based prototype ski waxes and their benchmarking against commercial PFAS-free, petroleum-based ski waxes, with emphasis on hydrophobicity, glide performance on snow, biodegradation, and hardness. The prototypes were formulated from bio-derived ingredients selected to be acceptable for topical application or ingestion, and adjusted based on melting points, hydrophobic tendencies, and learnings from earlier prototype testing. The guiding hypothesis was that greater water repellency could improve glide by helping remove the thin water film formed at the ski-snow interface. Hydrophobicity was quantified using contact angle measurements (water and ethylene glycol) at controlled room conditions, and additionally at sub-zero temperature (−5 °C) using a portable setup. Across wax formulations, static, advancing, and receding contact angles were broadly similar between bio-based prototypes and commercial comparators at both temperatures; however, commercial waxes showed slightly lower roll-off behavior with water at room conditions, while ingredient-level testing produced larger differences than finished wax comparisons. On-snow glide testing with multiple skiers did not clearly separate bio-based from commercial wax performance, indicating comparable glide under the tested conditions. The report also compared biodegradation using a compost respiration approach, finding the tested bio-based wax degraded more quickly than the commercial wax under the study assumptions. Hardness testing at −5 °C showed several commercial waxes were harder than their bio-based counterparts, with one exception where the bio-based “yellow” wax was harder than the corresponding commercial wax. The report concludes that the bio-based prototypes are competitive with conventional PFAS-free products while offering advantages in renewability and biodegradation, and notes future opportunities such as optimizing ingredient ratios, adding bio-based performance additives, and developing a liquid-format wax.

Role of the Droplet Lab Goniometer

A portable Droplet Lab contact angle instrument (tensiometer) was rented and placed in a freezer room at −5 °C specifically to enable sub-zero contact angle measurements when attempts to cool the lab-based setup faced practical issues (e.g., condensation and temperature mismatch between droplet and surface). Using ethylene glycol as the probe liquid (lower freezing point than water), the Droplet Lab system enabled evaluation of static contact angle and approximate roll-off behavior under winter-relevant conditions, supporting realistic screening of wax hydrophobicity for cold-weather consumer performance products.

Key Findings

  • All tested waxes were hydrophobic in room-temperature water testing (static contact angles >90°), and bio-based prototypes matched commercial waxes closely in static and dynamic (advancing/receding) angles.
  • Roll-off (sliding) angles with water at room temperature were slightly lower for commercial waxes versus corresponding bio-based prototypes, indicating marginally easier droplet shedding in that condition.
  • Ethylene glycol produced lower contact angles than water on the same wax surfaces and behaved differently, highlighting that probe-liquid choice can change apparent “hydrophobicity” ranking.
  • Using the Droplet Lab portable system at −5 °C (ethylene glycol), waxes still showed similar static contact angles, and roll-off differences were smaller (with added variability due to manual tilting).
  • On-snow glide performance was not significantly different across the tested waxes; bio-based prototypes were comparable to commercial PFAS-free products in the field test.
  • In compost respiration testing, the bio-based wax showed faster estimated complete degradation (reported estimate: 223 days vs 335 days for the commercial wax, under stated assumptions).

Why It Matters

For consumer performance products like ski wax, brands must balance glide performance, usability, and increasingly sustainability/chemical stewardship (e.g., PFAS-free positioning and renewable content). This study demonstrates a practical development pathway where contact angle + roll-off angle metrics can be used as formulation screens to guide ingredient selection and prototype iteration, while sub-zero testing with a portable goniometer helps validate that water-repellency behavior persists near real-use temperatures. The outcome, bio-based waxes performing comparably to established commercial products, supports decision-making around material substitution, eco-claims with performance parity, and potential quality specifications (e.g., minimum static angle / maximum roll-off angle thresholds) for batch-to-batch control.

Method Snapshot

  • Sample: Wax films prepared by melting a ski-wax layer onto microscope glass (wax iron).
  • Droplet/conditions: Room temperature measurements used 25 µL droplets and a tilt rate of 0.30°/s to obtain static/advancing/receding angles plus roll-off; sub-zero measurements used ethylene glycol at −5 °C with 4-5 droplets per sample using the portable Droplet Lab device.
  • Surface tension reference: Probe liquid surface tensions were listed (e.g., water 72.8 mN/m, ethylene glycol 47.7 mN/m) in Table 1.

Data Note

Figure reports the static contact angles and approximate roll-off angles at −5 °C obtained using the portable Droplet Lab contact angle instrument in the freezer room. (Instrument shown in Figure 3.)

Figure

Citation (APA Format)

Skedung, L., & Almgren Stenberg, E. (2024). Bio-based ski wax: Prototype development, hydrophobicity, hardness, biodegradation and glide performance on snow (RISE Report 2024:53). RISE Research Institutes of Sweden AB.

View Publication →

Water based adhesives

Water based adhesives, such as natural rubber latex, need to wet both the backing and the surface they stick to. Water has a high surface tension, so these adhesives wet low energy surfaces poorly. Surface free energy of the backing and the substrate shows which pairs are likely to bond.

Work out surface free energy from contact angles of two or more probe liquids, and compare candidates with the same liquids and model. Our contact angle to surface energy calculator does the arithmetic. Confirm the ranking with your own peel and holding tests.

Water based adhesives

How products interact with their packaging

Food and other products should release cleanly from their wrapping, while the film layers must still bond to each other. Water and oil contact angles show how strongly a packaging surface repels the product. Surface free energy shows whether a treated layer will take an adhesive or ink.

Food packaging is one of the uses our PFAS free reformulation page covers. Bio based polymers are another route: a fiber lab at Cornell University found that adding lignin raised the water contact angle of PLA fiber mats in nearly every blend.

How products interact with their packaging

Fogging on sports goggles

Fog forms when water condenses as tiny drops that scatter light. Anti fog coatings work by making water spread into a clear film instead. Water contact angle, read at a fixed early time, shows whether the surface still spreads water after washing, wiping and wear.

Fog tests in EN 168, ISO 16321-1 and ANSI/ISEA Z87.1 judge the lens itself, and none sets a contact angle limit. Contact angle is a fast check between those tests, not a substitute for them. Curved lenses need flat witness samples. Our anti fog coating validation page sets out the method.

Fogging on sports goggles

How water wets PDMS silicone

PDMS silicone is used in many consumer goods because it repels water. Its wetting still changes with cure, additives, treatment and age. Advancing and receding contact angles, and the hysteresis between them, show how strongly drops pin on the surface.

Sliding angle on a tilt stage shows whether drops actually roll off. ISO 19403-7 describes that roll off method; the Dropometer tilt stage reads up to 60 degrees. Our sliding angle guide explains how to set drop volume and tilt rate.

How water wets PDMS silicone

Adhesion of screen protectors

A screen protector holds only when its adhesive wets the glass. Fingerprint oils or cleaning residue lower that wetting and cause lifting or bubbles. Water contact angle at a fixed time after cleaning flags a residue film before the protector goes on. See glass cleaning verification.

Surface free energy also shows how a coating changes glass. A University of Toronto group used water, glycerol and diiodomethane to show a polyserotonin coating raised glass surface energy from about 47 to about 61 mJ/m2.

Adhesion of screen protectors

We are your partners in solving your Business & Technological challenges

If you are interested in implementing these or any other applications, please contact us.

Chapter 7: Standards and Guidelines

In an industry where precision reigns supreme, how can Consumer Products manufacturers ensure their products withstand scrutiny? The answer lies in standards and guidelines: the compass that guides them through the complex maze of quality and performance.

ISO 19403-7:2024, Contact Angle on a Tilt Stage (Roll-Off / Sliding Angle)

What it is

International standard method for determining the roll-off (sliding) angle, α, defined as the tilt angle at which a droplet just begins to move on a solid surface using a tilt stage. It also defines how to determine dynamic advancing and receding contact angles (θₐ/θᵣ) during roll-off to evaluate easy-to-clean / anti-adherent surfaces.

When to use it

Easy-to-clean / anti-adherent screening & benchmarking

Use when you need a quantitative droplet-mobility metric (α, and optionally θₐ/θᵣ) to compare coatings, treatments, or materials under a controlled droplet/tilt protocol.

QC mobility gate (lot-to-lot / process control)

Use when you want a repeatable acceptance criterion tied to droplet shedding (e.g., “α must be ≤ X°”) and monitored using replicates and a reference (“golden”) panel.

In-scope / Out-of-scope

In scope
  • Roll-off/sliding angle measurement on a tilt stage under a defined liquid, droplet volume, and tilt procedure (rate or step/dwell).
  • Optional dynamic θₐ/θᵣ during motion at (or immediately after) the onset of droplet movement, when your capture/analysis supports front/rear angle extraction.
  • Coated and treated surfaces where droplet mobility matters, including coated panels, plastics, glass, and films.
  • Replicate, multi-spot measurements intended to capture heterogeneity/defects and support robust reporting (e.g., median + IQR).
Out of scope
  • Static contact angle-only characterization (use a static CA method/standard if that’s the objective).
  • Direct surface energy or liquid surface tension measurement (requires other test methods).
  • Uncalibrated “self-cleaning” or performance claims without correlation to functional outcomes (cleanability/release tests).
  • Angles beyond the mechanical capability of the tilt stage (e.g., if the stage is limited to 0°-60°, true α > 60° cannot be directly measured).

Minimum you must report (checklist)

  • Test liquid (identity and preparation) and droplet volume.
  • Tilt protocol (tilt rate or step size, dwell time, starting angle, and maximum tilt achievable).
  • Specimen description (material/coating system, finish/texture, treatment history, and cleaning/handling method).
  • Environmental conditions (temperature, relative humidity, conditioning time if used).
  • Roll-off result: α (degrees) if roll-off occurs within range, or a censored outcome such as “No roll-off observed by X° (instrument limit)”.
  • Replicates & sampling plan (number of spots/locations) plus summary statistic (e.g., median) and spread (IQR or SD).
  • Validity/exclusion criteria (e.g., non-axisymmetric drop, baseline/edge-fit failure, visible contamination, vibration/tilt instability).
  • If reported: θₐ/θᵣ during motion (how front/rear angles were extracted and at what moment/frame relative to onset of motion).

Note: Roll-off angle is highly sensitive to droplet volume, liquid, and tilt rate/step rules, so these must be locked in an SOP for meaningful comparisons. If your instrument’s tilt range is capped (e.g., 0°-60°), surfaces requiring >60° must be reported as out-of-range (e.g., “α ≥ 60° / no roll-off observed”) rather than as a true ISO roll-off value.

How to interpret results (guardrails)

  • Lower α generally indicates easier shedding for that liquid and protocol, but do not compare α across different droplet volumes, liquids, or tilt procedures.
  • High static contact angle ≠ good mobility: strong pinning/hysteresis can yield high α or no roll-off within the instrument limit (including “sticky” regimes).
  • Treat “no roll-off by X°” as a censored measurement, suitable for screening/QC trending but not a substitute for an actual α if your spec requires values above X°.
  • Set pass/fail thresholds by correlation, linking α (and variability across spots) to functional outcomes (cleanability, release, anti-adhesion) and tracking drift with a reference panel.

Now It’s Your Turn

We hope this guide showed you how to apply surface science in the Consumer Products industry.

Now we’d like to turn it over to you: 

Feel free to leave a comment below—we’d love to hear from you.

Frequently asked questions

Which surface measurement should a consumer products lab start with?

Start with the claim on the box. For water repellent or easy clean claims, measure contact angle and sliding angle. For anti fog, measure water contact angle at a fixed early read time. For bonding, printing or labelling, measure surface free energy from two or more probe liquids. Our contact angle guide explains the core method.

Which standards apply to repellent and self cleaning surfaces?

ISO 19403-7 describes roll off angle on a tilt stage; the Dropometer tilt stage reads up to 60 degrees. ISO 27448 judges photocatalytic self cleaning coatings by water contact angle under UV light. The Dropometer measures the angles but has no UV lamp, so UV exposure is set up separately.

Why does my coating bead water but still look dirty?

A dirty coating can read like a worn one. Measure contact angle and sliding angle as found, then again after a gentle decontamination wash. If the readings recover, the coating was dirty. If they stay low, the coating has worn and needs reapplying. See hydrophobic coating performance verification.

Can contact angle show whether a PFAS free product still repels oil?

Yes. PFAS free coatings often match fluorinated ones on water but lose oil repellency. Measure both water and oil contact angles, fresh and after washing or abrasion. Contact angle does not show whether a product contains PFAS, and it does not replace your customer's spray rating or oil grade test. See PFAS free reformulation.

How do researchers test ski wax water repellency?

They measure contact angle and sliding angle on the waxed base, often at room temperature and below zero. A Utah thesis on ski wax and friction found performance depended most on hydrophobicity and chemistry. A study of low fluorinated Nordic waxes found contact angle did not track the marketed temperature ranges.

Can a portable instrument test wax at low temperature?

Yes, with a liquid that does not freeze. RISE in Sweden used a portable Droplet Lab instrument with ethylene glycol at minus 5 degrees to compare bio based ski wax prototypes. The report notes ethylene glycol gave lower angles than water and may not be the best screening liquid. See our ski wax use case.

Can contact angle compare fabric and mask layers?

Yes, as a comparison between layers. A 2022 study of disposable masks and an N95 respirator found polypropylene layers read between 107 and 120 degrees. The inner layer of a Level 3 mask read 78 degrees. Fabric texture raises the apparent angle, so compare like with like.

How accurate is the Dropometer?

The drop shape method was validated against a KRUSS DSA100E in two peer reviewed papers, one in Review of Scientific Instruments and one in Colloids and Surfaces A. Published contact angle accuracy is 0.35 degrees. Automatic edge and baseline detection gives the same reading from the same image. See our validation papers.

Standards, evidence and resources

1. Industry standards
  • ISO 27448: photocatalytic self cleaning test: Judges photocatalytic self cleaning coatings, such as titanium dioxide films on ceramics, by how water contact angle falls under UV light, with UV exposure set up separately.
Use cases
  • Glass cleaning verification: Water contact angle at a fixed time after cleaning flags residue films on glass before a coating, label or screen protector goes on, while it can still be cleaned.
  • Anti fog coating validation: Water contact angle at a fixed early read time, fresh and after washing and wiping, checks anti fog coatings on eyewear, goggles, face shields and visors between fog tests.
  • Hydrophobic coating performance verification: Contact angle and sliding angle, read before and after a decontamination wash, tell a worn water repellent coating apart from one that is simply dirty.
  • PFAS free reformulation: Water and oil contact angles, fresh and after washing or abrasion, show whether a PFAS free coating on cookware, textiles or packaging still repels oil as well as water.
  • Self cleaning and anti soiling coating validation: Contact angle, hysteresis and sliding angle mapped across coated zones show whether a self cleaning or easy clean surface still sheds water and dirt after outdoor exposure.
  • Ski wax hydrophobicity and glide testing: Water contact angle and sliding angle on waxed ski bases, at room temperature and below zero, help fluorine free wax makers screen formulas before glide tests on snow.
Case studies
  • Cornell University CCMR shared facility: Electrospun lignin and PLA fiber mats aimed at uses such as packaging and cosmetic care read higher water contact angles than neat PLA in nine of ten blends.
  • University of Toronto, two campuses: Research groups on two campuses use contact angle, sliding angle, surface tension and surface energy, with work on disposable mask layers and water repellent aspen leaves.
  • University of Utah polymers lab, ski wax: Researchers measured water contact angle on marketed low fluorine glide waxes and found the readings did not follow the temperature ranges each wax is sold for.
Client citations (our analysis of each paper) Use case collections Further resources