Only few modern comforts have such a direct influence on our well-being as our clothes do, which we wear directly on our skin. No other technology virtually touches us in this way. And the art of producing clothes is one of the oldest technologies developed by the human race. Even the people of the iceage protected their bodies from the cold with fur and nettings of plant fibres. This protective function of clothing has been the same ever since. But protection from cold, heat, and the weather are only some of the modern demands. There is also the human desire for beauty. For thousands of years, clothes have had a decorating function, too.
Now as then, we think of fashion and beauty and of function when we think of clothes. Seams can have a great influence on both. Seams are the connecting element, they make clothes from fabrics. They are often decoration and have the most various functions. Seams are tear proof, elastic, soft, watertight, weather-proof, easy-care, ... depending on the given requirements. And they are always decisive for the product quality.

Almost all home textiles have seam connections. Awnings, mattresses, quilts, upholstery, curtains, bed spreads – they all need seams to give them their desired form. First priority for seams on home textiles is their holding and fixing function. Seams on awnings connect individual fabric webs to make one big awning for protection from the sun. Seams on mattresses connect a piece of fabric with the desired fleece lining to make a soft bed. Upholstery seams form individual fabric pieces into three-dimensional covers. If the seams are visible on the outside of the finished model, they have an additional decorating function. Ornamental seams on upholstery or decorative topstitchings on quilts are good examples here.
In the area of home textiles, seam and product quality are linked closely. A broken seam on a sofa, a rippled seam on curtains, or a weather-related torn seam on an awning ruin a product’s quality as a whole. Reworking or repairing such problems is often very time-consuming and often very expensive, too. This is another motivation for producing quality.

Whether they are used in construction, in the industry, or in protective clothing – technical textiles are always hi-tech, innovative, and special products. Especially remarkable are their specific physical, chemical, and sewing technological characteristics. In the development of these products, the main focus is on their function. So, the requirements on their seams are special, too. Sometimes, even lives can depend on these seams. For example, if a seam on a parachute or an airbag does not meet the requirements, life is in danger.
Seams are one of the essential connections in technical textiles. They make very flexible and safe connections for producing complex two or three-dimensional products. Embroideries are often seen on technical textiles, too, for example in the production of fibre composites for light-weight structures in the aircraft industry. Whether sewn or embroidered, the sewing thread inserted into the textile material, must maintain or provide the function and partly even the demanding requirement profile of the entire product.  
The importance of a seam’s quality for the quality of the finished prod-uct is undoubted, and yet, the definition of seam quality is often hard to describe or determine.  What is seam quality? Are there any standards? How can seam quality be measured? AMANN, as an experienced sewing thread and seam specialist, knows the answers.

Quality means performance, conditions, and properties. If you want to assess a seam under these aspects, you need a detailed requirement profile. Yet, different seams make different requirements. Airbag seams, jeans seams, or upholstery seams – they all ask for different properties of the seam connections and thus have their individual requirement profiles.
However, there are indicators that are true for almost all seams. Their evaluation is the basis for assessing their quality. At AMANN, they are the basic knowledge of sewing. Every seam analysis begins with the checking of these properties. In addition, there are individual quality criteria. They must be worked out depending on the application and function. Image 1 shows the most important standard indicators and gives examples for individual quality criteria.