The vast majority of tax disc holders are screen printed on white pvc. However some organisations due to the design of their company logo prefer to have their tax disc holders screen printed onto coloured pvc’s. This is generally still straightforward but there are a number of additional considerations when screen printing onto a coloured material. This is particularly relevant when screen printing lighter colours onto a darker coloured pvc . Quite often if the base coloured pvc of the tax disc holder is darker than the colours to be screen printed onto it a base white will have to screen printed first underneath the lighter colours of the image. This is due to the fact that lighter colours tend to be more transparent and will significantly alter when printed onto a darker background. Additionally because pvc is an unstable print medium and is prone to movement the base white will have to be very slightly smaller than image to be screen printed onto it in order to ensure accurate registration and no show through of the base white. This is obviously not a problem when the coloured pvc tax disc holders are to be screen printed with a darker colour than that of the pvc.