[0001] This invention relates to a roof material for forming "Kaya" simulated roofs having
excellent fire retarding properties. More particularly, it relates to a halogen-containing
resin sheet-like roof material for forming a "Kaya" simulated roof. ("Kaya" is a gramineous
thatching plant of Japan having the botanical name Miscanthus sinensis Anderss.)
[0002] "Kaya"-roofed houses which still remain in agricultural districts of Japan provide
comfortable living conditions in that they are cool in summer and warm in winter and
they have been found in Japan from ancient times.
[0003] However, the true "Kaya"-roofed houses now remain only in a very limited number and
are on the brink of being swept away by modernization, because (1) "Kaya" itself is
becoming extremely scarce and difficult to obtain, (2) re-roofers are becoming rare,
(3) dried "Kaya" is very combustible and is heavily regulated for fire prevention,
and (4) for these reasons, "Kaya" roofs have been replaced by tiled roofs, etc. at
the time of roof repair or house re-building.
[0004] However, the "Kaya"-roofed houses are now being reevaluated in order to inherit old
cultures and skills and are being protected and fostered as a cultural inheritance
rich in local color and racial traits. Nevertheless, the situation is far from satisfactory
and the number of "Kaya"-roofed houses is decreasing year by year.
[0005] Meanwhile, the remaining "Kaya"-roofed houses provide their dwellers with most comfortable
living conditions in that they are cool in summer and warm in winter. Therefore, the
dwellers in these houses wish to preserve such houses as they are and live therein
as long as possible, and generally people wish to build "Kaya" simulated roofed houses.
However, these wishes are virtually unrealistic because the above-mentioned problems
of lack of "Kaya" and regulations for fire prevention cannot be solved, and tiled
roofs are now used unwillingly.
[0006] An object of this invention is to provide a roof material capable of being used in
place of "Kaya" and of providing a "Kaya" simulated roof.
[0007] Another object of this invention is to provide a roof material having excellent fire
resistant properties.
[0008] Other objects and advantages of this invention will become apparent from the following
description.
[0009] According to this invention, there is provided a halogen-containing resin sheet-like
roof material for forming a "Kaya" simulated roof which has a plurality of protuberant
strips on its at least one side.
[0010] This invention will be described in detail referring to the accompanying drawings,
in which Fig. 1 is a sketch of a "Kaya" simulated roofed house in which the roof material
of this invention is used; Fig. 2 is a partially cut-away perspective view of an example
of the roof material of this invention to be used in the house of Fig. 1; Fig. 3(a)
is a sectional view of a part of the house of Fig.
1 along the A-A line; Figs. 3(b) and 3(c) are variations of Fig 3(a); and Fig. 4 shows
partially cut-away sectional views of other examples (A) to (K) of the roof material
of this invention. In Figs. 1, 2, 3a, 3b and 3c, 1 represents a "Kaya" simulated roofed
house; 2 represents a roof portion; 3 represents a sheet-like roof material; 3a represents
a cylindrical protuberant strip of the roof material 3; 4 represents a pillar; 5 represents
a beam; 6 represents a rafter; 7 represents a sheathing; 8 represents an eaves portion;
9 represents a heat insulating material; and a represents the distance between the
end of the lower roof material and the end of upper roof material when they are placed
head to tail while being partially overlapped.
[0011] This sheet-like roof material to be used in forming "Kaya" simulated roofs according
to this invention has a plurality of protuberant strips on its at least one side and
can form a "Kaya" simulated roof as seen in Fig. 1 by placing the roof materials of
this invention side by side and head to tail, optionally partially overlapping one
another, and piling them up in the necessary portions (for example, the eaves portion).
[0012] It is preferable that the sheet-like roof material of this invention has on its at
least one side a plurality of protuberant strips each having a shape similar to "Kaya"
so that when the roof materials are piled up in many layers as can be seen in Figs.
3(a) to 3(c), spaces can be formed. The sectional shape of each protuberant strip
may be a polygon (e.g., triangle, tetragon, pentagon or the like), an arc, a circle
or the like. The sectional shape is preferably an arc or circle such as a semicircle,
a circle or a quasi-circle. The sheet-like roof material of this invention is formed
by connecting a plurality of such protuberant strips to one another throughout their
lengths. When the sheet-like roof materials are placed on a roof board so that the
strips exist along the inclination of the roof and rain water runs down through the
grooves between the protuberant strips.
[0013] When the sheet-like roof material has the protuberant strips on both sides, the sectional
shapes of the strips are preferably of a circle. When the sheet-like roof material
has the strips on only one side, the sectional shape is preferably of a semicircle
or a quasi-circle because spaces are easily formed when the sheet-like roof materials
are piled up on one another.
[0014] It is preferable that each of the protuberant strips has a width (the outside diameter
of the section when the sectional shape is of a circle, a semicircle or a quasi-circle)
which is substantially the same as the diameter of "Kaya", namely, a width of about
2-30 mm, preferably about 3-20 mm, more preferably about 5-15 mm. The protuberant
strips may be hollow or solid but preferably are hollow cylinders. Each protuberant
strip has preferably a length of 5-100 cm, preferably 10-50 cm.
[0015] The sheet-like roof material of this invention can be prepared in various shapes
such as a shape as shown in Fig. 2 wherein a plurality of cylinders, preferably about
2 to 250 cylinders, more preferably about 10 to 100 cylinders are directly connected
to one another along their lengths, the shape (A) in Fig. 4 wherein cylinders are
connected via fine flat sheets along and throughout their lengths, and the shape (B)
in Fig. 4 wherein protuberant strips having a semiarc section are directly connected
to one another along and throughout their lengths. Of these, the shape of Fig. 2 and
the shapes (A) and (D) in Fig. 4 are preferred.
[0016] The halogen-containing resin cylinder may have laminated to its inside a layer of
a resin or rubber such as ABS, polymethyl methacrylate or the like, or may be filled
with said resin or rubber.
[0017] In roofing a house with the sheet-like roof materials of this invention, the roof
materials are placed and connected side by side and head to tail, optionally partially
overlapping, on a roof board so that rain water does not leak through the connections.
Desirably, each roof material has, on its longitudinal edges, fitting means as shown
in Fig. 2 which make its connection to the adjacent sheet-like roof materials possible
and the arrangement of the roof materials easier.
[0018] Sheet-like roof materials having shapes as shown in Fig. 2 and shapes (A), (D), (E),
(G), (H) and (I) in Fig. 4 may be formed by extrusion-molding the resin into cylinders
or bars and then connecting them to one another along their lengths. Sheet-like roof
materials having the shape of Fig. 2 and shapes (A) to (K) in Fig. 4 may also be integrally
molded by means of an extruder.
[0019] Shapes (C) and (G) to (K) in Fig. 4 can also be formed by press molding.
[0020] The sheet-like roof material of this invention has a length of 5-100 cm and a width
of 5-100 cm, preferably a length of 10-50 cm and a width of 5-50 cm.
[0021] The sheet-like roof materials of this invention are placed on the sheathings 7 of
a roof portion ordinarily in the arrangement as shown in Fig. 3(a), 3(b) or 3(c),
wherein the lengths of the protuberant strips are placed along the inclination of
the roof. It is possible, however, that the sheet-like roof materials are arranged
head to tail while overlapping them by 1-50 cm, preferably 2-30 cm, more preferably
3-20 cm in the inclination direction of the roof and fixing them, for example, with
nails, an adhesive or the like. In this case, from the viewpoint of appearance of
roof, the distance between the end of the lower roof material and the end of the upper
roof material as shown by a in Fig. 3c is preferably 1-30 cm, more preferably 2-20
cm. After the arrangement of the roof materials, ends of the roof materials piled
up in the eaves portion of the roof are cut to form an eaves of the desired shape
so that the section of each protuberant strip can be seen from the exterior, whereby
the house can have a "Kaya" simulated roof.
[0022] Although the sheet-like roof materials of this invention may be piled up in many
layers on the sheathings, this is economically disadvantageous, and hence, a heat
insulating material may be substituted for a part of the roof materials present inside
the roof which cannot be seen from the exterior as shown in Figs. 3(a) to 3(c).
[0023] The sheet-like roof material of this invention can be prepared in the form of a block
so that the placement of the roof material on the sheathings can be made more easily.
[0024] The sheet-like roof material of this invention, which can make the appearance of
the roof a "Kaya" simulated roof, is required to be fire resistant in order to prevent
the house from catching fire. Therefore, the sheet-like roof material of this invention
is made of a halogen-containing resin, which includes resins containing chlorine,
fluorine, bromine or the like. Examples of the halogen-containing resins are, for
example, chlorine-containing resins such as polyvinyl chloride, vinyl chloride copolymers,
polyvinylidene chloride, vinylidene chloride copolymers and the like, and fluorine-containing
thermoplastic resins such as polyvinyl fluoride, vinyl fluoride copolymers, polyvinyldiene
fluoride, vinylidene fluoride copolymers and the like. Of these, the polyvinylidene
fluoride resin is particularly preferred.
[0025] The polyvinylidene fluoride resin used as a preferable material may be not only a
homopolymer of vinylidene fluoride but also a vinylidene fluoride copolymer having
a vinylidene fluoride content of at least 50 mole%, preferably at least 70 mol%. The
comonomers which may be used for the copolymers include, for example, ethylenically
unsaturated carboxylic acid esters such as methyl methacrylate and the like, halogen-containing
olefins such as ethylene tetrafluoride, propylene hexafluoride and the like; and olefins
such as ethylene, propylene and the like. The roof material of this invention may
also be made of a polyvinylidene fluoride composition containing said polyvinylidene
fluoride resin and an ethylenically unsaturated carboxylic acid ester resin (e.g.,
a polymethacrylate), the polyvinylidene fluoride resin content thereof being at least
75% by weight. The above resin may contain particulate, needle-like or fibrous fillers
and reinforcing agents and further contain various additives such as pigments, dyes,
stabilizers, flame retardants and the like.
[0026] The fillers and reinforcing agents include titanium white, glass fibers, alumina,
talc, etc. Their sizes can be varied.
[0027] It is also useful to form fine convexes and concaves on the surface of the molded
article by incorporating a filler having a large particle size, thereby rendering
the molded article appearance "Kaya"-like.
[0028] The sheet-like roof material of this invention for a "Kaya" simulated roof is specifically
explained in more detail below referring to the accompanying drawings. This example
is only by way of illustration but not by way of limitation.
[0029] Fig. 1 is an example of a "Kaya" simulated roofed house in which the sheet-like roof
material of this invention is used; Fig. 2 is a partially cut-away perspective view
of an example of the sheet-like roof material of this invention to be used for forming
the roof of the "Kaya" simulated roofed house of Fig. 1; Fig. 3(a) is a sectional
view of an eaves portion of the "Kaya" simulated roofed house of Fig. 1 along the
A-A line; Figs. 3(b) and 3(c) show variations of Fig. 3(a); and Fig. 4 shows partially
cut-away sectional views of variations (A) to (K) of Fig. 2.
[0030] In Fig. 1,
1 refers to a "Kaya" simulated roofed house; 2 to a roof portion; and 3 to a polyvinylidene
fluoride resin sheet-like roof material.
[0031] The above roof portion 2 has a structure as shown in Figs. 3(a) to 3(c).
[0032] That is, a plurality of beams 5 are horizontally mounted on a plurality of pillars
4 having different heights installed vertically, and on the beams 5 are mounted a
number of rafters 6 in parallel at the inclination caused owing to the height difference
of the pillars 4. Sheathings 7 are placed on the rafters 6 and fixed thereon with
nails or the like so that no spaces are caused between the sheathings 7, and polyvinylidene
fluoride resin sheet-like roof materials 3 each having a length of 40 cm and a width
of 30 cm formed by connecting 20 to 30 cylinders 3a each having an outside diameter
of 5-15 mm and an inside diameter of 3-14 mm are placed side by side and head to tail,
optionally partially overlapping, on and throughout the sheathings and piled up in
the eaves portion 8, after which ends of the roof materials 3 in the eaves portion
are cut to form an eaves 8 in Fig. 3(a).
[0033] When the roof portion 2 is formed by piling up the sheet-like roof materials 3 in
plural layers, a part of the roof materials existing inside the roof portion can be
replaced by, for example, a heat insulating material 9 in order to save the roofing
cost. The heat insulating material 9 or the like is fixed on the sheathings 7 and
its upper and side portions are covered with the roof materials 3 so that the heat
insulating material 9 or the like are not seen from the exterior. Thus, the "Kaya"
simulated roofed house
1 in which the sheet-like roof materials of this invention are used looks like a true
"Kaya"-roofed house.
[0034] As mentioned above, the sheet-like roof material of this invention for a "Kaya" simulated
roof makes it possible to build a house resembling conventional "Kaya"-roofed houses
inherited from ancient times and having an appearance rich in local color and racial
traits.
[0035] The houses built with the roof materials of this invention provide the most comfortable
living conditions in that they are cool in summer and warm in winter.
[0036] Moreover, using the roof material made of a polyvinylidene fluoride resin having
a flame retardancy, the roof portion of the house has excellent fire resistance and
further has a good weather resistance, enabling safe use of the house over a long
period of time.
1. A halogen-containing resin sheet-like roof material for "Kaya" simulated roofs
having a plurality of protuberant strips on its at least one side.
2. The roof material according to Claim 1, wherein the halogen-containing resin is
a polyvinylidene fluoride.
3. The roof material according to Claim 2, which is a sheet-like material formed by
connecting a plurality of halogen-containing resin cylinders to one another along
their lengths.
4. The roof material according to Claim 1, wherein each of the protuberant strips
has a width of 2-30 mm.
5. The roof material according to Claim 1, which has fitting means on both sides for
connecting it to the adjacent roof materials.
6. The roof material according to Claim 1, wherein each of the protuberant strips
has a circular, semicircular or quasi-circular section.
7. The roof material according to Claim 1, which has a length of 5-100 cm and a width
of 5-100 cm.
8. The roof material according to Claim 1, which has 2 to 250 protuberant strips.
9. The roof material according to Claim 1, wherein each of the protuberant strips
has the form of a cylinder which has laminated to its inside a layer of an ABS or
polymethyl methacrylate.