Project status on July 10, 2026: The protocol is published before measurements begin so that the method is not adjusted after seeing the results. No absorption or wash resistance figures are yet presented as results. Raw data, photos, and unfavorable results will be added to the same folder after each step.
This study aims to measure the absorption, absorption rate, drying, and resistance after 10, 25, and 50 washes of a Caspirolus paper towel. It does not constitute an independent laboratory test. Its value lies in a method announced in advance, repetitions, publication of limitations, and preservation of raw data.
Methodological reference: ISO 20158:2018 standard describes the measurement of the absorption time and capacity of textiles designed to absorb water. The Caspirolus protocol is not presented as an ISO certification; it adopts the requirement for announced variables and comparable measurements.
Why publish the protocol before the results?
A commercial demonstration can easily show only the best trial. A method published before data collection reduces this risk: water volumes, durations, washing steps, and calculations are set in advance. If a modification becomes necessary, it will be dated and explained instead of silently replacing the initial method.
The grammage of 380 g/m² describes the mass of the textile per surface area; it alone does not prove the quantity of water retained, the absorption rate, or the lifespan. These properties must be measured separately. To understand this distinction, consult our guide on washable paper towel materials.
Planned product and samples
- four new Caspirolus sheets from the same batch, identified A, B, C, and D;
- advertised format: 25 × 25 cm;
- advertised total grammage: 380 g/m²;
- composition and structure identical to the product sheet at the time of the test;
- snaps recorded as present or absent, without attributing an effect on absorption to them.
Sheet A serves as a new control. Sheet B is followed up to 10 washes, sheet C up to 25, and sheet D up to 50. This small number of samples will not allow generalization of the results to all production or all washable paper towels on the market.
Equipment used
- a kitchen scale accurate to the gram;
- a flat container and a graduated measuring cup;
- water at room temperature;
- a stopwatch;
- a clean, flat, non-absorbent surface;
- a ruler and a camera placed in the same location;
- the detergent, dosage, and program actually used during the cycles;
- a separate record sheet for each sheet.
Sample preparation
Each new sheet will be photographed flat, front, back, and at the seams, with a visible ruler. Dry weight, width, height, overlock stitch condition, pattern clarity, presence of deformation, and snap function (if present) will be recorded.
Before an absorption weighing, the sheet must dry for at least 24 hours under conditions as similar as possible. The room temperature and, if available, relative humidity will be recorded.
Test 1: Absorption capacity
- Weigh the completely dry sheet and record this mass as
M_dry. - Pour 100 ml of water into a flat container.
- Place the absorbent side on the water for exactly 10 seconds, without pressing.
- Lift the sheet and let it drain for 5 seconds without wringing it out.
- Weigh it immediately and record
M_wet. - Calculate the mass of water retained:
M_wet − M_dry. - Repeat three times after complete drying.
The three values, their average, minimum, and maximum will be published. A demonstrably disturbed trial will only be excluded with a dated justification; its value will remain visible in the raw data.
Test 2: Absorption rate
- Place the dry sheet flat, absorbent side up.
- Pour 20 ml of water into the center from a fixed height of 5 cm.
- Time how long it takes for the free water to no longer be visible.
- Stop the measurement at 60 seconds if water remains present.
- Repeat three times after complete drying.
A representative trial will be filmed without acceleration or cuts. This measurement is method-dependent: it should not be compared to a figure from another protocol as if it were the same experiment.
Test 3: Drying time
- Add exactly 50 ml of water to each dry sheet.
- Hang the sheets on the same drying rack, with the same spacing.
- Record the available temperature and humidity.
- Weigh each sheet every 30 minutes.
- Consider it returned to dry state when the mass is within 2 g of the reference dry mass.
The result will only apply to the described conditions. Winter drying in a humid room and ventilated summer drying are not directly interchangeable.
Test 4: Wash resistance
The actually recommended program will be used at 30 or 40 °C, with the same detergent, the same dosage, and a load as comparable as possible. The exact conditions will be recorded in the test log.
At cycles 1, 5, 10, 25, and 50, dimensions, dry mass, seams, pattern, possible deformation, and snaps will be checked. Absorption capacity and rate tests will be repeated. No accelerated aging will be presented as 50 real washes.
Possible comparison with paper towels
Paper and textile do not have the same mass or exactly the same function. Any comparison will use at least two clearly identified paper references. Measurements will be presented both per sheet and, if possible, at comparable mass. All results will be published, including when they are unfavorable to Caspirolus.
No extrapolation in CO₂ emissions, liters of water, trees, or "rolls saved" will be drawn from this use test. Such claims would require a life cycle analysis and additional assumptions that are not measured here.
Data that will be published
- the wash log and the date of each measurement;
- the dry and wet masses of the three repetitions;
- the averages, minima, and maxima;
- the absorption and drying times;
- the dimensions before and after washing;
- untouched photos at the announced stages;
- incidents, deviations from the protocol, and excluded data with their justification;
- limitations and product modifications decided based on observations.
What the study can and cannot conclude
It can describe the behavior of the tested samples under the announced conditions and show the observed evolution over the cycles. It cannot prove universal performance of all Caspirolus batches, establish general superiority over all brands, guarantee a lifespan for every customer, or demonstrate an overall environmental benefit.
Results will be distinguished from verifiable commercial characteristics. Pending their publication, the Caspirolus product sheet should not include any absorption coefficient or promise after 50 washes.
Version history
- July 10, 2026: Initial publication of the method before data collection.
For current practical advice, also see how to wash a reusable paper towel and our comparison reusable paper towel or disposable paper towel.
To put these measurements in context for the daily choice of format, material, and number of sheets, also consult our complete guide to choosing a reusable paper towel.