The History & Manufacture of Squeegee Rubber

Unger: About Rubber - History and Manufacture: Unger Enterprises partnered with some of the world's most renowned rubber experts to develop the best formula for window cleaning. After months of research and testing, our team developed a rubber that holds up to the strictest product specifications in professional window cleaning.
In its natural form, rubber was used for centuries before it was re-discovered by Christopher Columbus. Rubber was called 'Caoutchouc' by the Indians of Central and South America from the Indian word 'cahuchu' meaning weeping wood from its origins as a sap in tree bark. Its modern name, "rubber," is derived from its use to "rub out" pencil marks.
After rubber was introduced to western culture and it became a more popular material, the products for which it was used could not stand up to extreme cold. In 1843, Charles Goodyear patented the process of vulcanization, removing sulphur from rubber to waterproof and winterize it, creating a healthy market for rubber goods.
According to the Rubber Manufacturers Association, the use of and demand for rubber products is pervasive in today's consumer and industrial economies. Sixty percent of rubber production is used in tire manufacture, but the balance is used to make rubber components supplied to a range of other industries. This includes squeegee rubber. According to the International Rubber Study Group, of the 8,682 million tons of natural rubber produced in 2005, North America alone consumed 1,316 million tons of it. But the Asia Pacific region is perhaps the world's largest rubber user with 5,202 million tons consumed in 2005.
Available in two forms, natural or synthetic, the rubber used for window squeegees is called pure gum rubber, is tan in color, soft, pliable and elastic. As a non-marking elastomer, it is resistant to organic salts, ammonia, acids and alkalis which makes it ideal for window cleaning.
Unger's new, long-lasting rubber formula contains a higher rubber content with less fillers compared to current window cleaning rubbers. The new rubber formulation is softer and glides more smoothly across wet and dry windows without sticking to the dry part of the glass. Also, when it hits dirt objects on glass, the softer rubber is more malleable and will not nick or tear when passing over this debris. Available in a re-closable blister pack, the rubber is protected and stored flat.
There are many considerations to attend to when selecting rubber. Not only does Unger have the right formula, but we are confident that when window cleaning professionals use Unger's ErgoTec Soft Rubber they will experience the ease of use and efficiency for which it is designed. Our new formula, size ranges and storage options provide everything necessary for a high-quality window cleaning job every time.
Rubber was named by Joseph Priestly in 1770 who found that dried latex could rub out pencil marks. In its natural state, rubber is an elastic hydrocarbon polymer found in the form of a milky emulsion known as latex in the sap of plants and trees such as fig trees and dandelions. The main source of latex for creating rubber is the Para rubber tree, discovered in South America where rubber was first processed in the 19th Century.
Natural rubber is manufactured primarily in the countries of Latin America, Africa and Asia by combining latex with formic acid, which coagulates the rubber into sheets. The sheets are then wrung out in a press and shipped to factories for further processing and vulcanization, whereby rubber is heated and combined with sulfur to improve its resilience and elasticity.
The rise of synthetic rubber occurred just before World War I for development of rubber tires with the growth of the automobile industry.

Ettore: Often imitated, never duplicated, his original squeegee design has remained essentially unchanged since its inception. His secret was, and is, in the rubber for this is the essential heart of the system. A razor sharp square edge, supple, smooth, consistent which leaves glass perfectly clean and streak free. Indeed, every Ettore product is 100% guaranteed to deliver nothing less than flawless performance. Ettore Steccone's pioneering spirit has assured Ettore's position as the undisputed industry leader. Today the company provides every conceivable tool and convenience to make window cleaning more fun, efficient and effective.


Mark gives us his point of view on rubber on this weeks tool talk - taking into account the top market selling window cleaning rubber in the world of Ettore, Unger & Pulex.

FOR A QUALITY SQUEEGEE THE KEY IS THE RUBBER (Pulex): The rubber blade is the main component of every squeegee because it is the element that comes into direct contact with the glass and dirt. It is so important that the material with which the squeegee is made - steel, brass or plastic - and the mechanics play a minor role. This is because the vast majority of squeegees on the market - economical ones sold in the household item department and often imported from the Far East - do not work as they should. Without mentioning molded plastic blades, which are definitely inferior, standard rubber cleaning blades are made of ordinary extruded rubber, which is obtained continuously from rolls dozens of meters in length and cut into sections ready to be fitted into the tool. This type of rubber does not have the features of a real mix of vulcanized rubber as it is extruded ready for use and not cut to size, the result being a blade with a rough, rounded edge. This means it becomes deformed when it comes into contact with dirt which is abrasive and washing solutions which are aggressive, or is exposed to atmospheric agents, or subjected to friction on glass and rubbing against window frames or under the eaves. As these blades are made using a very quick and easy process without any finishing touches or inspections, they are relatively inexpensive and obviously they wear out very quickly. Also, they virtually always leave unsightly marks all over the glass. And the wider the squeegee, the more evident the marks.The basic condition for a top quality squeegee is a perfect combination of three specific features of the blade - a) the type and nature of the rubber, b) the quality of the mix, c) the edge of the blade. As regards the first feature, Pulex rubber is real vulcanized natural rubber (NR), which is compression molded, item by item, from a meter-long (approx. 36”) strip. As natural rubber is of vegetable origin it is important that its organic chemical features are as constant and homogeneous as possible, so it must always be obtained from the same country, in this case Malaysia, and also from the same sites in that country. Despite this, there is always the risk of the mix containing particles and foreign bodies, some minute, due to the fact that it comes from a tree in a plantation and is collected, handled and packed using traditional manual methods that are still very rudimentary. As regards the second feature, it is important for the raw material to provide a mix that can be processed carefully and is free from impurities as far as possible, having all the necessary properties concerning molecular dispersion, cross-linking, elasticity, snap, resilience, hardness, resistance to chemical and atmospheric agents, coloring and surface smoothness. Thanks to the addition of various special additives formulated in over two decades of research and development, the grade of the mix of Pulex rubber is specifically calibrated for cleaning glass. The third aspect is also very important. There is no point in using expensive first-rate ingredients and developing a perfect mix for a specific use if the rubber is not cut precisely to get a perfectly linear cleaning edge to the blade. So in this final stage the rubber strip is molded using a high-power press, and cut in half by sophisticated machinery using a special process. This gives a blade that is about a meter long (36”) and has a very sharp edge. After careful inspection, the blade is cut into different sizes. And it is precisely on the perfection of the edge that the Pulex quality control system focuses. In order to detect defects, Pulex has been researching special equipment for years, the only manufacturer to devote considerable resources to this particular problem. And now Pulex has come up with a machine for optical, electronic and computerized control with respect to the edge of the blade. Exploratory laser rays “read” the degree of perfection of the cut and the two sharp edges and assess whether there are any defects in the less critical surrounding areas. This is why Pulex rubber blades, which are the result of a lengthy multi-stage process, are no comparison with the blades used in ordinary squeegees. They are universally known as TQR, Total Quality Rubber, i.e. the only rubber blades to be used in a total quality squeegee. In addition, as Pulex rubber blades come in two different degrees of shore hardness - standard and soft - they meet the needs of all window cleaners, worldwide and irrespective of their skills.