Materials
Porosity
One property predicts more about an intimate product than any other. It is invisible, it is rarely printed on the box, and it is testable at the kitchen sink.
A porous material has openings at the surface leading into the body of the material. The openings can be microscopic and still matter, because the relevant organisms are smaller still. Bacteria measure around one micrometre. A channel a hundred times that size is, from their point of view, a corridor.
Why cleaning does not reach it
Soap works by surrounding oily material so water can carry it away. That requires mechanical contact: the soap solution has to reach the dirt, and the water has to flush it out. Inside a narrow channel, surface tension resists entry, flow is close to zero and whatever is already there stays put. Rinsing the outside of a porous object is genuinely effective on the outside and does nothing below it.
This is why disinfectants are not the answer either. A disinfectant needs contact time with the organism. If the liquid cannot reach the organism, contact time is irrelevant.
The home test
- Wash and dry the object completely.
- Place a single drop of water on a flat area and leave it for two minutes.
- A non porous surface holds the drop with a clean edge and wipes away dry.
- A porous surface pulls the edge of the drop outward and leaves a dark patch that takes minutes to fade.
A second check uses a drop of unscented mineral oil on the base of the object. On a non porous surface it sits and wipes off. On a porous one it darkens the material and the mark remains. Both tests are done on an inconspicuous area, and both are more reliable than any wording on the packaging.
Living with a porous object
Porosity is not an emergency. It is a limit. A condom over a porous object provides a complete barrier and costs nothing in feel for most people. Immediate washing rather than delayed washing removes the material before it has time to be drawn in. Complete drying before storage denies the moisture that everything else depends on.
The honest instruction for a porous object is to treat it as a consumable, not as equipment.
Where the line falls
| Material | Porous | Practical consequence |
|---|---|---|
| Platinum silicone | No | Cleans fully, tolerates boiling |
| ABS and rigid plastic | No | Cleans fully, no heat treatment |
| Glass and steel | No | Cleans fully, tolerates boiling |
| TPE, TPR, jelly, skin-like blends | Yes | Surface cleaning only, limited service life |
| Untreated wood and stone | Yes unless sealed | Depends entirely on the seal remaining intact |
Sealed wood sits in an awkward middle. A sound seal makes the surface non porous; a scratch through it makes the object porous at exactly the point that is hardest to inspect. That is a reasonable trade for an object handled carefully and a poor one for anything that lives loose in a drawer.