[pageLogInLogOut]

#Research & Development

Textile daylight management when the winter sun is at an angle

When the sun is currently shining, shading textiles face particular challenges. On the one hand, they should allow as much daylight as possible into the rooms during the dark season. On the other hand, the angle of incidence of the sun's rays is so low that the light is particularly dazzling - much more so than in summer. The German Institutes of Textile and Fiber Research (DITF) are using special light measurement techniques to research suitable shading textiles.
The DITF light lab. Photo: DITF
The DITF light lab. Photo: DITF


Daylight enhances well-being and has many advantages over artificial lighting. Sensible daylight management can therefore increase the ability to perform and concentrate. As less artificial light is required and solar gains and losses are used for room air conditioning, daylight management also saves energy.

Scheme for determination of the cut-off angle with 1 light source, 2 diffuser, 3 measurement sample on motorized rotating stage, 4 collimating lens, 5 spectrometer. Drawing: DITF
Scheme for determination of the cut-off angle with 1 light source, 2 diffuser, 3 measurement sample on motorized rotating stage, 4 collimating lens, 5 spectrometer. Drawing: DITF


Textile daylight systems influence the incidence of light and are mainly designed to be movable. Internal systems include, for example, roller blinds, folding blinds and curtains. External systems are external venetian blinds, awnings and screens that are guided in front of the façade. The DITF can precisely measure daylight behavior in its light and dark laboratories - even beyond existing standardized test methods.

A test method developed in Denkendorf allows the glare control of solar protection devices to be re-evaluated and has been included in the standard to determine the cut-off angle. This cut-off angle describes the extent to which a solar protection device can block the transmission of direct light from a certain angle of incidence. In the currently valid standard, glare control is quantified using the two characteristics of normal and diffuse light transmittance. For solar protection devices with an openness coefficient of 1-3 %, a higher glare control class can be achieved. This applies to cut-off angles of 65° or less. The cut-off angle is determined by an angle-dependent measurement of the direct light transmittance. During the test, the solar protection textile is rotated in a modified test sample holder from the zero point until the direct light transmittance falls below a defined threshold value. This process is repeated after a gradual azimuthal rotation of the test sample, in other words a rotation of the textile in the test sample holder. Depending on the symmetry properties of the sample, up to 29 individual measurements may be required to determine the cut-off angle.

At the DITF, testing and development facilities for other photometric requirements such as incident light, self-luminous textiles and light-conducting textiles are available for industrial product developments.

The direct transmission of a textile screen when changing the angle of incidence and the specific angle of rotation. Photos: DITF
The direct transmission of a textile screen when changing the angle of incidence and the specific angle of rotation. Photos: DITF



More News from Institut für Textil- und Verfahrenstechnik Denkendorf

More News on Research & Development

#Research & Development

ALADIN paves the way for circular and demand-driven textile production in Europe

Textile production can be organized sustainably by utilizing short supply chains and preventing overproduction. This can already be achieved today by intelligently connecting and efficiently utilizing existing infrastructure. At the same time, production becomes circular when innovative technologies and materials are used that enable high-quality recycling. The ALADIN research project, launched in May 2026 and co-funded with five million euros under the EU Horizon Europe program, is creating the conditions for this.

#Research & Development

TERIS reaches milestone: Fraunhofer consortium develops new standards for tire analysis

In the “TERIS” project, the Fraunhofer institutes ICT, IGD, and IWM—led by the Fraunhofer Institute for Structural Durability and System Reliability LBF—have reached a decisive milestone. For the first time, the teams aim to generate, analyse, and predict tire wear in the laboratory in a standardized and practical manner. As part of this milestone, results are now available on reference abrasion, particle analysis, tribological models, AI-based surface analysis, a test bench concept, and methods for accelerated aging and VOC detection. The tire industry, testing services, and environmental agencies will in future benefit from reliable, rapid laboratory procedures for emissions assessment.

#Research & Development

Geotextiles made from recycled materials: GREEN leads the way into the industry

For the industry, recycled materials are creating new opportunities in geotextile production. In the GREEN project, the Fraunhofer Cluster of Excellence Circular Plastics Economy CCPE demonstrates that recycled polypro-pylene (PP), polyethylene terephthalate (PET), and high-density polyeth-ylene (HDPE) can be processed into nonwovens, fibers, and membranes that meet industrial requirements. This creates opportunities for use in existing production lines and new value chains in the geotextile market.

#Research & Development

2026 general meeting of the Friends and Supporters of RWTH Aachen at ITA

The Friends and Supporters of RWTH Aachen e. V. (proRWTH) looked back on a successful year of support at their 2026 general meeting. The meeting took place at Institut für Textiltechnik (ITA) of RWTH Aachen and was combined with a joint session of the Executive Board and the Administrative Board. Before the general meeting began, participants were given a guided tour of ITA, providing them with fascinating insights into current research and development topics in textile engineering.

Latest News

#Textile processing

YKK develops concept EXCELLA® zipper tape using nonwoven fabric partially derived from used clothing

YKK Corporation has developed a concept version of its premium EXCELLA® zipper series made from nonwoven fabric sheets created by fiberizing used clothing and other textile materials. Based on a proposal by fashion designer Yuima Nakazato, this item was created as a result of collaboration between Nakazato, Seiko Epson Corporation and YKK. The concept zipper was incorporated as a material component for pieces in the newest YUIMA NAKAZATO Couture Collection, “INFERNO,” which was unveiled in Paris, France on July 8, 2026.

#Textiles & Apparel / Garment

Texworld Apparel Sourcing Paris highlights evolving global sourcing landscape

From 31 August to 2 September 2026, Texworld Apparel Sourcing Paris will bring together more than 1,000 international exhibitors at Paris-Le Bourget Exhibition Centre. This edition reflects the new global balance of textile and apparel sourcing, highlighting a strong diversity of sourcing countries — some unexpected.

#Textile processing

Dedicated car seat model of SHIMA SEIKI’s P-CAM® R Cutting Machine unveiled

Leading Japanese textile solutions provider SHIMA SEIKI MFG., LTD. of Wakayama, Japan, showed a special version of its P-CAM® R multi-ply computerized cutting machine dedicated to the production of car seats for the first time, at a private exhibition held over two days on Thursday, July 2nd and Friday, July 3rd at the Kariya City Industrial Promotion Center in Aichi Prefecture.

#Nonwovens

Katharina Obergruber appointed to the Management Board of Sandler AG

The Supervisory Board of Sandler AG has appointed Katharina Obergruber to the company’s Management Board. Effective September 1, 2026, the Board will consist of Philipp Ebbinghaus (CEO), Dr. Ulrich Hornfeck (currently CCO, future COO), and Katharina Obergruber (CCO). Katharina Obergruber, currently Chief Sales Officer Hygiene and member of the Management Team of Sandler AG, will assume responsibility for all sales activities as Chief Commercial Officer. She will assume this role from Dr. Ulrich Hornfeck, who will focus primarily on production and supply chain topics.

TOP