Post Office Sponge Sheets

Post Office Sponge Sheets

Post Office Sponge Sheets

Alongside the many standard sponge, foam and rubber materials stocked by Advanced Seals & Gaskets Ltd which are split down and supplied as sheets, we also specialise in supplying sheets of other unique materials such as “Post Office Sponge” or orange open cell natural sponge as it is also known.

Post office sponge is manufactured and stocked in buns (blocks) of various sizes and thicknesses up to 80mm, which vary depending on density,  which we can split down using state of the art splitting machines, meaning we can supply sheets starting from as little as just 1.5mm, in two meter by one meter in size as standard, or cut down to bespoke sized sheets and pads.

Our on-site laminating service not only allows us to laminate layers of sponge together to create greater depths, but also enables us to supply them coated with a choice of self-adhesives, foils or even laminated to other materials to produce composite sheets.  Post office sponge sheets are a popular product as they give the customer the flexibility to be able to cut their own parts such as strips, gaskets or pads out as and when required or to cover larger surfaces reducing the need for joins in the material.

Product Enquiry

For information on Post Office Sponge Sheets please complete the following quick enquiry or call us on +44(0)1384 252555.






    Key Characteristics of Using Post Office Sponge Rubber

    • Colour: Orange
    • Structure: Open cell (fine or medium)
    • Density: 140 to 600 Kg/m3
    • Sheet Size: up to 2120mm x 920mm (depending on density)
    • Temperature Range: -40ºC - +80ºC
    • Tensile Strength:  0.23 N/mm2 - 1.2 N/mm2 approx (vary between densities)
    • Elongation at Break:   455% - 817% (vary between densities)
    • Resistances (Ozone/Acids/Alkalis/oils/fats/solvents): Not resistant
    • Flammability:  Highly flammable 

    Full technical data can be supplied upon request,
    or downloaded from our online portal.

    What are Post Office Sponge Sheets?

    Orange open cell is manufactured using high quality natural rubber, and available in a range of densities from 160kg/m3 to 600kg/m3  and with a choice of pore sizes creating very soft or very firm materials each suited to different applications. Orange open cell natural sponge is recognisable by its bright orange colouration and the visible cell structure which is designed to be absorbent to hold liquids within it (you may have seen this sponge in the post offices on which they would moisten stamps before the self adhesive backed ones were introduced!). Sheets of Post office sponge are split to order from master blocks and are taken in thicknesses starting from as little as 1.5mm, and can be supplied as 1m x 1m or 2m x 1m in size. Sheets can be taken in a plain or self adhesive finish, or even laminated to other materials.  ASG use sheets when smaller components or low quantities of parts are required, and are sometimes preferred by customers as it saves them money and waste by not having to take full blocks or rolls of material when they may only require a small amount.

    Why use Post Office Sponge Sheets?

    Post Office sponge sheets and components cut from them are usually found in wet applications, labelling, packaging and vacuum lifting, etc.  As the material is not resistant to oils, acids or alkalis, it is limited for use in certain industrial or automotive applications.   As with many other types of block foam, post office sponge can be split down and supplied as sheets, or further converted into a range of finished usable products including rollers, pads, washers and strips.

    Post office sponge has been developed so that it can be produced in a choice of densities, pore sizes and firmness in order for it to be utilised in a wide range of applications. Post Office sponge sheets can be manufactured in a range of sizes and thickness, laminated with a choice of foils and self-adhesives applied to one or both faces.  For very thick sheets  or  where a combination of properties are required, open cell sponge sheets can be laminated together in layers or can be laminated to other materials for use within more specialist applications

    Benefits of Using Open Cell Natural Sponge Rubber

    • Good abrasion resistance
    • Soft and flexible to seal around uneven or complex shapes
    • open cell structures also allows for water absorption
    • Excellent recovery following repeated compression
    • Good tear resistance 

    Other Grades of Sponge Materials Available

    • EPDM - medium, firm, semi-open cell, high temperature
    • Neoprene - FR, medium, firm
    • Silicone
    • Polyurethane
    • Open Cell industrial sponge

    The Advantages of using Post Office Sponge Sheet

    Using sheets of post office open cell natural sponge offers numerous advantages, available in a choice of soft- feel or very firm densities, with an  open cell structure allowing the material to be used in wet applications for water absorption for example in within packaging applications where these components  help protect goods from impact damage or liquid spillages,whilst allowing for the circulation of moisture and gas when the application requires it.

    As this material catches liquid and holds it - it’s perfect for applications which then re-use the retained moisture such as paint pads and rollers, or floats used for plastering and tiling, etc.  Post office sponge sheets are available in a range of thicknesses, all offering excellent compression recovery particularly when it’s used  for repetitive loading and distortion applications such as packaging and vacuum lifting.

    Orange open cell natural rubber depending on density is available in sheet sizes of up to 2120 x 920mm and in thicknesses up to 80mm, all of which can be split down or laminated to achieve non-standard sized sheets and can also be further converted  into perfectly fitting finished cut products such as washers, gaskets, strips, pads or discs.  

    Have a Question About Post Office Sponge Sheets?

    Please contact us using the form below or by calling us on +44(0)1384 252555.