JPS5930101Y2 - Roofing core material - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a roofing core material made of nonwoven fabric.

Conventionally, random woven fabrics have been used as roofing core materials, but because they are insufficiently strong, reinforcing yarns and coarse woven fabrics are also used.

However, when such reinforcing yarns and fabrics are used together, the asphalt is not sufficiently impregnated into the yarn during asphalt processing, and water leaks from this area and the waterproof layer is destroyed, resulting in poor durability of the waterproof layer. .

The present invention aims to eliminate these drawbacks and provide a roofing core material that is strong and has excellent impregnation properties with waterproofing agents such as asphalt. This is a roofing core material made of a nonwoven fabric of synthetic fibers that are intertwined with each other in an oriented state and have a large number of small pores.

Here, the strength required for the roofing core material is as specified in JIS A 6022 (1977) when the roofing is used as a core material for asphalt impregnation, and The basis weight is 120 g/m2 or more, and the strength of the raw fabric is 12 kg/cm or more in the vertical direction and 8 kg/cm in the horizontal direction.
In addition, the elongation in the vertical direction is specified to be 6% or more, and the elongation in the horizontal direction is specified to be 9% or more, and furthermore, the 3% tensile stress after impregnating asphalt with a product basis weight of 1500 g/m2 or more is 3% in the vertical direction. Stress is 6kg/cm or more, horizontal stress is 4
It is specified as kg/Cm.

The present invention is aimed at increasing the vertical and horizontal strength of the roofing core material, that is, the original fabric specified by the JIS, while maintaining a balance between the strength in both directions.

First, the nonwoven fabric used in the present invention is created by ejecting a fluid such as air or water locally from a number of nozzles onto a card or a web in which striated fibers are oriented, to cause fiber entanglement and the formation of small pores. This can be obtained most easily by simultaneously performing the same process, but other methods include mechanical needling,
It can also be obtained by applying physical manipulation.

It should be noted that although it is natural that the small pores of the nonwoven fabric in the present invention have no fibers at all, there are also some fibers present in the small pores, and the fiber density is lower than that in other parts. It is preferable because it has less structural changes such as shrinkage, is stronger, makes it easier to obtain a uniform reinforcing effect as a waterproof layer, and is also stronger.

For example, the velocity of the processing fluid, the pressure,
It is possible to change it by means of ejection.

The one shown in Fig. 1 is a plan side view of the roofing core material of the present invention, in which the fibers are entangled with each other in a well-oriented state, and has a large number of small holes 1. 1 is a plan view of a roofing core material of the present invention having small holes 1 in which fibers 2 are present and the fiber density is smaller than in other parts.

The roofing core material of the present invention is subjected to asphalt processing as usual and used for waterproofing, but structurally, the fibers are oriented and it has many small holes. Because it is extremely porous, it has good impregnability with asphalt, etc. (that is, there are no asphalt-impermeable parts anywhere in the roofing, and the asphalt permeates throughout the roofing with an almost uniform thickness). It has moderate elasticity and sufficient strength in at least one direction, so it has excellent workability.

A case in which the roofing core material according to the present invention is used, a case B in which a conventional long-fiber nonwoven fabric called spunbond is used as the roofing core material, and a roofing core in which the spunbond is reinforced with glass fibers at intervals of 7 mm are used as the roofing core material. An example of an experiment in which material C was impregnated with asphalt is as follows.

The constituent fibers of the roofing core material (original fabric) of the present invention are vinylon stable, and the fibers are arranged almost in one direction, with 20 to 30 holes of about 1 to 2 mm2 per cm2. Approximately 95g/m with perforated non-woven fabric
2), the spunbond fibers are polyester and the basis weight is approximately 90 g/m2.

Note that the stress in the table below refers to the stress value at 3% elongation after asphalt impregnation.

As is clear from the results on the wood surface, the roofing core material A of the present invention has vertical and horizontal strength, and the stress is about the same as C, but the elongation is moderate, so it is easy to install and is at this level. Because it has such elongation, it can also cope with ground movement after construction.

Furthermore, since the roofing core material has holes, the asphalt penetrates the entire surface with a uniform thickness, resulting in smooth construction and a flat finished surface.

On the other hand, conventional B has a large unbalance between vertical and horizontal strength and has too high elongation, making it difficult to install, and the thickness of the impregnated asphalt is uneven due to the density of fibers in the nonwoven fabric. About 30% was observed.

Also, the same (Conventional C is satisfactory in terms of strength, but on the other hand, its elongation is too small, so it is inferior to A in terms of responding to ground movement after construction, and moreover, the glass fiber used as the reinforcing thread The fact that there was about 15% of the asphalt impermeable area around the area is not perfect in terms of durability.

Note that polyvinyl alcohol-based synthetic fibers are particularly effective as the fibers used in terms of chemical resistance and heat resistance, and polyester-based synthetic fibers can also be used.

[Brief explanation of the drawing]

1 and 2 are plan side views of the roofing core material of the present invention.

Claims (3)

[Scope of utility model registration request] (1) A roofing core material made of a synthetic fiber nonwoven fabric in which most of the short fibers are intertwined with each other in a substantially unidirectionally oriented state and have a large number of small pores. (2) The roofing core material according to claim 1, which is a registered utility model and is made of polyvinyl alcohol fiber. (3) The roofing core material according to claim 1, which is a utility model registration and is made of polyester fiber.