JPS5930100Y2 - Core material for roofing - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a novel core material for roofing.

Conventionally, non-woven fabrics have been mainly used as core materials for roofing, but since most of these are random non-woven fabrics, they are insufficiently strong, and reinforcing threads are appropriately combined or coarse fabrics are laminated. used.

However, in such core materials, the asphalt is not completely impregnated into the reinforcing yarns and fabrics, which may cause water to leak from these areas or destroy the waterproof layer, causing problems with the durability of the roofing. There are cases.

Here, the strength required for roofing core material is as defined in JISA 6022 (1977) when the roofing is used as a core material for asphalt impregnation, and The basis weight is 120g/
m2 or more, the tensile strength of the raw fabric is 12 kg/crn or more in the warp direction, 8 kg/cm or more in the horizontal direction, and 6% or more in elongation in the warp direction. ,
The elongation in the horizontal direction is specified as 9% or more, and the 3% tensile stress after impregnating asphalt with a product basis weight of 1500 g/m2 or more is 6 kg/cm or more in the vertical direction and 4 kg/cm in the horizontal direction. It is stipulated as follows.

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.

The present invention aims to provide a core material for roofing that has sufficient strength and has excellent asphalt impregnation properties.
The feature is that multiple nonwoven fabrics made of synthetic fibers, most of which are intertwined with short fibers oriented in almost one direction, and which have many small holes, are layered so that the fibers intersect with each other. This is a core material for roofing made by bonding.

First, the nonwoven fabric used in this invention is a web in which carded or filamentous fibers are oriented, and the fibers are entangled by fluid jetting, needling, etc., and a large number of small holes are formed. It is effective to spray air, water, etc. from a large number of nozzles to entangle the fibers and form small holes at the same time.

Note that the term "small pore" here refers to a part where the fiber density is lower than other parts, in addition to a through hole where no fibers are completely present. can be obtained by changing .

Particularly, the latter one is good because it has less shrinkage due to its structure.

These nonwoven fabrics have structural features such as oriented short fibers and a large number of small pores, so they have extremely good impregnability with asphalt, etc. during asphalt processing and waterproofing (i.e., roofing There are no impermeable parts of asphalt anywhere in the roofing, and asphalt permeates all parts of the roofing to a nearly uniform thickness, allowing for uniform impregnation.

As the fibers constituting these nonwoven fabrics, polyvinyl alcohol synthetic fibers are particularly preferred from the viewpoint of weather resistance, chemical resistance, and heat resistance, but polyester fibers are also used.

In the present invention, a plurality of such nonwoven fabrics are stacked and bonded together so that the orientation directions of the fibers of the nonwoven fabrics intersect, thereby forming a core material for roofing.

The cross direction of each fiber in the nonwoven fabric due to this superimposition is
It is necessary to ensure that the strength (strength) and elongation (elongation) required for a roofing core material are not biased in the vertical or horizontal direction (that is, not unbalanced in one direction).

For example, when stacking two nonwoven fabrics, it is effective to make the fiber direction of each nonwoven fabric perpendicular to the weft and weft directions.In this case, a product with the same balance of strength and elongation as a woven fabric can be obtained; In this case, the fiber direction may be changed by an arbitrary angle, for example, by 90° or 60°.

A water-resistant adhesive such as an acrylic adhesive or a vinyl acetate adhesive may be appropriately selected for adhering the nonwoven fabric, but the smaller the amount of the adhesive used, the less it will impede the impregnating properties of the asphalt.

What is shown in FIG. 1 is a perspective view showing the core material for roofing of the present invention, in which two sheets of nonwoven fabric 1.1 are intertwined with each other with oriented fibers and have small pores 2 and 2'. ' are stacked and glued together perpendicularly to the longitudinal and longitudinal directions.

According to this structure, each nonwoven fabric has short fibers oriented in one direction and has a large number of small pores, and since these are laminated, the fabric becomes porous as a whole and has excellent impregnation properties during asphalt processing.

Moreover, each nonwoven fabric has great strength along the fiber direction,
Since these are intersected and integrated, there is no extreme imbalance in strength, elongation, etc., and it has a moderate elongation, so the waterproof layer will not be destroyed during or after waterproofing construction. Never.

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 in almost one direction, with 20 to 30 holes of about 1 to 2 mm2 per cm2. perforated nonwoven fabric (weighing 30 g/
m2), three sheets are laminated with the fiber directions perpendicular to each other by 90 degrees (approximately 90 g/m2), and the spunbond fibers are polyester and the material is approximately 85 g/m2.
It is.

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 a balance in vertical and horizontal strength and stress, and has a medium elongation, making it easy to install and capable of achieving this level of elongation. Because it has a certain degree of strength, it can also cope with ground fluctuations after construction.

What's more, because the asphalt permeates the entire roofing core material with a uniform thickness, construction work is smooth and the finished surface is flat.

On the other hand, with conventional B, there is a large imbalance between vertical and horizontal strength and the elongation is too high, making it difficult to install.Also, the thickness of the impregnated asphalt is uneven due to the density of fibers in the nonwoven fabric. Approximately 30% of the locations were 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.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a perspective view showing an example of the present invention, and 1° 1' shows fibers arranged in one direction and intertwined with each other, with a large number of small holes 2, 2'. FIG. 2 is an enlarged view of section P in FIG. 1.

Claims (4)

[Scope of utility model registration request] (1) A plurality of nonwoven fabrics made of synthetic fibers in which most of the short fibers are entangled in a state in which they are oriented almost unilaterally and have many small holes are overlapped and bonded so that the fibers intersect with each other. A core material for roofing that is characterized by: (2) A core material for roofing according to claim 1, which is a utility model registration and is made of polyvinyl alcohol fiber. (3) A core material for roofing according to claim 1, which is a utility model registration and is made of polyester fiber. (4) The roofing according to claim 1, 2, or 3, which is made by bonding two nonwoven fabrics together so that their fiber arrangement directions are perpendicular to each other. Core material for use.