Pinking is a pink or red dye which is produced via the normal metabolic process of a specific bacteria found inside vinyl seat cushions. The pink dye or "Pinking" becomes visible to the human eye when it wicks or soaks up through the vinyl from the inside out. There are other surface molds which can be mistaken for Pinking by producing a red hue but differ greatly in that they can be cleaned using traditional products.
The bacteria which causes Pinking flourishes in warm, moist environments where they have a food source. For example, if a boat cushion is wet in its interior then any bacterial spores which land on or near the stitching of cushions or were already present at the time of manufacturing will start to grow if they find a food source and its warm enough. The food source for the bacteria which causes pinking can be sun tan oils, sunscreen, human body oils or other oils which are deposited inside the cushion at the time of manufacture.
The Pinking bacteria family does have strains that have been known to infect humans but there is no evidence that the Pinking bacteria can cause human health related issues.
The bacteria which causes Pinking is everywhere. It's in the air, in soil, and in the water. Because of this combined with the fact there are seems and other ways for the bacteria to enter cushions there is a continual risk that the bacteria could infect other parts of the cushion.
If properly prepared and then treated the same pink stain will not return in the same location where it was treated.
No. There is no known existing solution which can prevent Pinking. However, our scientists think, eat and this remains the holy grail of any future product.
Vinyl manufacturers have been trying to solve Pinking on PVC based fabric for over 50 years. It is a very hard problem to solve and history has shown that entrenched problems like this are normally solved outside the industry or domain where the problem exists.