This is one of the most popular synthetic raw material in use. The variations in colour and configuration are almost limitless, and are, therefore, equally suitable for all areas of the clothing industry, and especially for Haute Couture, where Real Horn is not, for whatever reason, viable.

Polyester is a petrochemical based synthetic material, and comes in a variety of colours and configurations. The raw material comes in three forms: Rod; Sheets or Blanks.

 

Rods:

These are made to a specific diameter, and are usually about one meter in length. Blanks or Discs are cut from these rods to the thickness required for later machining. The advantage of carrying rods in stock, is that various thickness' of blanks can be cut from the same batch of material, which is very useful when making fashion buttons, where the small ones are perhaps 4mm or 5mm thick, and the larger ones up to 8mm or 10mm.

Sheets:

These are flat slabs, made centrifugally to a pre-determined thickness, in a variety of colours and configurations, from which blanks are later cut to the required size for matching. Again, the advantage of this is that more than one size can be cut from as sheet, if necessary.

Blanks:

These discs are normally cut from either sheet or rod, in some cases before the Polyester is "cured", thus saving on the wastage factor. However, it does have limitations, as it means a greater stock holding to cover the full size range required by the clothing manufacturers. It is important to remember that configurations achieved from Polyester rod manufacture, cannot be copied in sheet form and vice-versa, because of the different techniques.

The blanks are machined and drilled to extremely fine tolerances, on specialised machines custom-built for the purpose. The tools are made in accordance with the shape required on the back and the front, and the buttons drilled either four-hole, two-hole or one hole, through a "pip-shank" which has been turned on the back. The various finishes are obtained by barreling operations.

 
One of the great advantages of Polyester as a material, is that it can be surface tinted, so the base range of colours required is far less than in Urea Formaldehyde, for example, which cannot be tinted, but still allowing the flexibility of matching any colour of cloth that is required.
In all cases, irrespective of the raw material used, stringent quality control checks are made during manufacture, and again at the final inspection stage, where buttons are sorted and packed. The sorting operation on Real Horn buttons is of particular importance, as the degree of variation with the natural material, has to be kept within strict tolerances.