A nonwoven fabric useful for forming composite panels includes specific amounts of reinforcing fibers, a polyimide, and a block polyestercarbonate-polysiloxane. The nonwoven fabric has a density of 0.03 to 0.2 gram/centimeter.sup.3, an areal density of 100 to 400 gram/meter.sup.2, and a tensile modulus of 50 to 1000 megapascals. Also described are a method of forming the nonwoven fabric, a composite formed from the nonwoven fabric, and a method of forming the composite.

A synthetic leather has high flame retardance in addition to excellent mechanical strength and durability, which may yield a covered article having an excellent texture, and a covered article which has been covered with the synthetic leather. The covered article includes a synthetic leather and a covered article covered with the synthetic leather, the synthetic leather having a fiber base material layer including a non-woven fabric containing: a non-melting fiber A having a high-temperature shrinkage rate of 3% or less, and a thermal conductivity, conforming to ISO22007-3 (2008), of 0.060 W/m.Math.K or less; and a thermoplastic fiber B having an LOI value, conforming to JIS K 7201-2 (2007), of 25 or more.

Disclosed are a sound absorbing and insulating material and a method for manufacturing the same. The sound absorbing and insulating material may be manufactured by impregnating a polyimide binder into a nonwoven fabric formed of a heat-resistant fiber. As such, the sound absorbing and insulating material may have superior sound-absorbing property, flame retardancy, heat resistance and heat resistance, thus being applicable to parts maintained at high temperatures of 300 C. as well as at room temperature and moldability due to the use of the polyimide binder.

Disclosed are a sound absorbing and insulating material and a method for manufacturing the same. The sound absorbing and insulating material may be manufactured by impregnating a polyimide binder into a nonwoven fabric formed of a heat-resistant fiber. As such, the sound absorbing and insulating material may have superior sound-absorbing property, flame retardancy, heat resistance and heat resistance, thus being applicable to parts maintained at high temperatures of 300 C. as well as at room temperature and moldability due to the use of the polyimide binder.

A random mat material including fiber bundles, said fiber bundles including fibers having an average fiber length of 5 to 100 mm, and having an average number N of fibers in the fiber bundle that satisfies:

[00001]$\frac{1.5{10}^5}{D^2}<N<\frac{4.5{10}^5}{D^2}$

wherein D is the average diameter of fibers in the fiber bundle, expressed in micrometers, and the standard deviation SD.sub.N of the number of fibers in a fiber bundle satisfies:

1,000<SD.sub.N<6,000

wherein at an end of the fiber bundle, the number of the fibers in a fiber bundle becomes less from center to edge of the fiber bundle in a fiber direction.

A random mat material including fiber bundles, said fiber bundles including fibers having an average fiber length of 5 to 100 mm, and having an average number N of fibers in the fiber bundle that satisfies:

[00001]$\frac{1.5{10}^5}{D^2}<N<\frac{4.5{10}^5}{D^2}$

wherein D is the average diameter of fibers in the fiber bundle, expressed in micrometers, and the standard deviation SD.sub.N of the number of fibers in a fiber bundle satisfies:

1,000<SD.sub.N<6,000

wherein at an end of the fiber bundle, the number of the fibers in a fiber bundle becomes less from center to edge of the fiber bundle in a fiber direction.

A semi-finished product includes a partly reinforced assembly (11) of a nap layer (12, 13, 14, 15) made of a non-woven fiber nap (16) and an additional fiber layer (21, 22), stacked face-to-face. The nap layer includes carbon fibers, aramid fibers, or mineral fibers, such as glass or basalt fibers, having a preferred orientation (VR). The assembly is produced by a layering process. The nap layer and the fiber layer are free of additional macro proppants. The additional fiber layer includes a web thread group (23, 24) of individual adjacent threads. The fiber layer includes carbon fibers, aramid fibers, or mineral fibers, such as glass or basalt fibers and has an exclusive fiber orientation (FA). The nap product is partly reinforced by local connection points between the fibers of the different layers. The semi-finished product has a high directional strength and a high maximum drapability at the same time.

A semi-finished product includes a partly reinforced assembly (11) of a nap layer (12, 13, 14, 15) made of a non-woven fiber nap (16) and an additional fiber layer (21, 22), stacked face-to-face. The nap layer includes carbon fibers, aramid fibers, or mineral fibers, such as glass or basalt fibers, having a preferred orientation (VR). The assembly is produced by a layering process. The nap layer and the fiber layer are free of additional macro proppants. The additional fiber layer includes a web thread group (23, 24) of individual adjacent threads. The fiber layer includes carbon fibers, aramid fibers, or mineral fibers, such as glass or basalt fibers and has an exclusive fiber orientation (FA). The nap product is partly reinforced by local connection points between the fibers of the different layers. The semi-finished product has a high directional strength and a high maximum drapability at the same time.

A heat resistant fiber assembly contains heat resistant fibers having a glass transition temperature of 100 C. or more, the heat resistant fibers being bonded together.

A heat resistant fiber assembly contains heat resistant fibers having a glass transition temperature of 100 C. or more, the heat resistant fibers being bonded together.