Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.

Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.

Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.

Abstract: A viscoelastic plastic interlayer intended to be arranged between two glass sheets of a glazing in order to provide it with vibroacoustic damping properties, includes two outer layers of thermoplastic adhesive, an inner layer arranged between the two outer layers, the inner layer having a loss factor tan ? greater than or equal to 1.6 at 20° C. and for a frequency range of between 2 kHz and 8 kHz, and first and second barrier layers arranged respectively between the outer layers and the inner layer 3, and composed of a viscoelastic plastic material.

Abstract: A viscoelastic plastic interlayer intended to be arranged between two glass sheets of a glazing in order to provide it with vibroacoustic damping properties, includes two outer layers of thermoplastic adhesive, an inner layer arranged between the two outer layers, the inner layer having a loss factor tan ? greater than or equal to 1.6 at 20° C. and for a frequency range of between 2 kHz and 8 kHz, and first and second barrier layers arranged respectively between the outer layers and the inner layer 3, and composed of a viscoelastic plastic material.

Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.

Abstract: The present invention is directed to systems and methods which utilize a cavity ring-down spectroscopy (CRDS) technique implemented for the measurements of vapor transmission rate. In one embodiment, the vapor content to be measured is contained within an optical cavity. Light is then injected into the cavity up to a threshold level and the decay time of the injected light is measured. When the wavelength of the injected light is resonant with an absorption feature of the vapor the decay time increases linearly as a function of vapor content. In this manner, vapor content causes a longer decay time and thus the amount of vapor passing through the film (film permeation rate) can be determined in real-time.