Patent Application
20140194022
The present invention relates to a building material and, more particularly, to rooftop canvas.
There are more storms, hurricanes, and tornados due to climate warming and extreme climates. The building materials, including rooftop canvas, should be adjusted according to the climate change. Rooftop canvas is a modern building material and use advanced polymers to shield ultraviolet rays and provide protection. In addition to withstanding strong sunlight and providing resistance to decomposition, the rooftop canvas possesses excellent resistance to aging due to heat.
Safety is the top priority while installing the rooftop canvas on rooftops. However, a worker slips easily on conventional rooftop canvas made of asphalt when the rooftop canvas is heated, moistened, or stained with oil. Furthermore, the conventional rooftop canvas has low tear strength. Thus, the safety of the worker on the rooftop canvas is risky.
Rooftop canvas according to the present invention includes a twill texture layer having a plurality of flat warp strips extending in a longitudinal direction and a plurality of flat weft strips extending in a lateral direction perpendicular to the longitudinal direction. An imaginary line passing through an intersection of one of the plurality of flat weft strips and one of the plurality of flat warp strips and an intersection of another of the plurality of flat weft strips adjacent to the one of the plurality of flat weft strips and another of the plurality of flat warp strips adjacent to the one of plurality of flat warp strips is inclined relative to the longitudinal direction and the lateral direction. The twill texture layer is superimposed on a first covering layer.
Each of the plurality of flat warp strips and the plurality of flat weft strips includes at least one corrugated face, and the twill texture layer includes at least one corrugated surface.
Preferably, the rooftop canvas further includes a second covering layer. The first covering layer is sandwiched between the twill texture layer and the second covering layer.
Each of the plurality of flat warp strips and the plurality of flat weft strips is made of polyolefin, preferably polypropylene.
The first covering layer is made of polyolefin, preferably polypropylene.
The second covering layer is made of one of a thermoplastic elastomer, a polyolefin elastomer, or a polyolefin plastomer, or a mixture of polypropylene and at least one of a thermoplastic elastomer, a polyolefin elastomer, and a polyolefin plastomer.
The rooftop canvas according to the present invention possesses anti-slipping properties, light shielding properties, and water permeation resistance.
The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.
With reference to
In the form shown in
Since the flat warp strips 111A and the flat weft strips 111B intersect with each other, are mutually superimposed at different sections, and press against each other, the surfaces of the twill texture layer 11 are rugged, uneven, and fluffy. Each of the flat warp strips 111A and the flat weft strips 111B has a width in a range from 1.5 to 5.0 mm. The width of the flat warp strips 111A can be different from the width of the flat weft strips 111B to obtain a twill texture layer H of a desired pattern. Each of the flat warp strips 111A and the flat weft strips 111B has at least one corrugated face such that the twill texture layer 1 includes at least one corrugated surface that is more rugged, uneven, and fluffy.
The rooftop canvas 1 further includes a first covering layer 12. The twill texture layer 1 is superimposed on the first covering layer.
The rooftop canvas 1 has anti-slipping properties. Specifically, when a worker wearing rubber shoes stands on the surface of the twill texture layer 11, the bottom faces of the rubber shoes bite into the surface of the twill texture layer 11 without slipping. It has been proved in tests that slipping would not occur even if the rooftop canvas 1 is placed on a rooftop having an inclination angle of 34 degrees. The safety of the worker on the rooftop canvas is assured.
With reference to
The rooftop canvas 1 according to the present invention also possesses light shielding properties. Since at least one face of each of the flat warp strips 111A and the flat weft strips 111B is corrugated, at least one surface of the twill texture layer 11 is corrugated and, thus, rugged, uneven, and fluffy. Each of the flat warp strips 111A and the flat weft strips 111B can shield and reflect light beams from different angles.
The rooftop canvas 1 according to the present invention also possesses water permeation resistance. Since the flat warp strips 111A and the flat weft strips 111B are corrugated, are woven with each other, are overlapped with each other, and squeeze each other, they fill gaps therebetween and, thus, possess water permeation resistance.
With reference to
The rooftop canvas 1 can further include a second covering layer 13. The first covering layer 12 is sandwiched between the twill texture layer H and the second covering layer 13. The second covering layer 13 provides enhanced water-resistant effect. In the form shown, each of the flat warp strips 111A and the flat weft strips 111B is made of polyolefin (polymers obtained from addition polymerization). These polymers are obtained from polymerization of many identical or different simple olefin molecules and possess better water permeation resistance properties. The first covering layer 12 is preferably made of polyolefin to enhance the water permeation resistance properties. The polyolefin for producing the flat warp strips 111A, the flat weft strips 111B, and the first covering layer 11 is preferably polypropylene (PP), obtaining effects of light weight and resistance to chemicals and heat.
The second covering layer 13 is made of one of a thermoplastic elastomer (TPE), a polyolefin elastomer (POE), or a polyolefin plastomer (POP), or a mixture of polypropylene (PP) and at least one of a thermoplastic elastomer (TPE), a polyolefin elastomer (POE), and a polyolefin plastomer (POP).
Thermoplastic elastomers (TPE), or referred to as thermoplastic rubbers (TPR), possess properties of both of rubber and thermoplastic plastics. They are in a molten state and can be easily processed at high temperatures. At normal temperature, they have better tensile strength and are easy to process with low energy consumption and can be recycled.
Polyolefin elastomer (POE) is an elastic composite material having excellent toughness and excellent resistance to aging. Polyolefin elastomer has better flowability and is compatible with poleolefin.
Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the essence of the invention. The scope of the invention is limited by the accompanying claims.
