JPS649428B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound absorbing board for a ceiling formed by paper-making a fiber material.

With this type of ceiling sound absorbing board, when sound hits the sound absorbing board, the sound is broken down by the fibers and transmitted to the air inside the sound absorbing board, where it loses its energy through friction with the fibers. It's getting old. High-frequency sounds are well absorbed in this way, but low-frequency sounds are not so well absorbed.

Therefore, in order to increase the sound absorption rate of low-frequency sounds,
For example, an air layer of 100 mm to 300 mm is provided on the back side of the sound absorption board.

However, in order to provide the above-mentioned air layer, a base structure is required, which poses a problem of poor workability.

The present invention has been made in view of the above circumstances, and its purpose is to provide a sound absorbing board for ceilings that does not require a base structure, has excellent workability, and is highly nonflammable.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1a is a plan view showing an example of a sound absorbing board for a ceiling according to the present invention, and FIG. 1b is a sectional view. According to the same figure,
The ceiling sound absorbing board A is made of a mixture of esterified pulp fibers and inorganic fibers.
The central part 2 excluding the peripheral part 1 is a rectangular plate-shaped ceiling part 2
It has a shape in which a side plate portion 2b is provided on the peripheral edge of the portion a. In other words, the central portion 2 is approximately trapezoidal and has a space B in which the lighting fixture 3 can be placed. The apparent area of this ceiling sound absorbing board A is approximately 35% larger than that of a flat sound absorbing board of the same size (when the vertical and horizontal dimensions are 606 mm x 606 mm). Therefore, the sound-absorbing area is large, and a sound-absorbing effect can be obtained more than a flat sound-absorbing plate of the same size. Note that the ceiling portion 2a may be formed in a hemispherical shape.

The inner surface 4a of the ceiling sound absorbing board A on the space B side is formed to have a higher density than the outer surface 4b. For example, the density of the surface 4a is 0.30 g/cm ³ and the density of the surface 4b is 0.30 g/cm 3 .
It is set at about 0.154g/ ^cm3 . This density difference is determined by the direction in which the stock is made during paper making, as will be described later. Therefore, the mechanical strength of the entire ceiling sound absorbing board A is obtained, making it difficult to deform, and the inner surface 4
The cord of the lighting fixture 3 can also be locked to a.

The inner surface 4a may be spray-coated with, for example, a fireproofing paint containing 75% by weight of inorganic titanium oxide in an amount of about 70 g/cm ² to 100 g/cm ² .

In addition, ⁵⁰ g/cm 2 of liquefied ceramic containing 40% by weight of amorphous ceramic (SiO ₂ , Al ₂ O ₃ ) and 60% by weight of inorganic binder was applied to the inner surface 4a and outer surface 4b.
Approximately 100 g/cm ² may be applied.

In this way, a density difference can be created between the inner surface 4a and the outer surface 4b, and heat resistance and heat insulation properties can be improved. In particular, when the liquefied ceramic containing 40% amorphous ceramic and 60% inorganic binder is applied, it not only has heat resistance and heat insulation properties, but also has no sudden changes in heat, no deformation due to impact, no cracks, and has a curved exhaust temperature curve. Temperature time area (tdθ) of the part where exceeds the standard temperature curve 11.25 Smoke coefficient
A semi-non-combustible soft fiberboard is obtained, which is compatible with semi-non-combustible materials with a value of 0.6. In addition, the ceramic composition is usually alumina (Al ₂ O ₃ ) silica (SiO ₂ ), but if the weight ratio of alumina (Al ₂ O ₃ ) is increased, a semi-nonflammable soft fiberboard that can withstand high temperatures can also be obtained. I can do it.

In other words, even though the main material is flammable organic material, the following Ministry of Construction Notification No. 1231 2 of 1978
It corresponds to semi-noncombustible material (class 2 flame retardant) specified in the fourth regulation.

Items stipulated in Ministry of Construction Notification No. 1231 regulations (1) There shall be no significant deformation that is harmful to fire safety.

(2) Not to generate extremely harmful gases.

(3) The width of the crack is one-tenth or less of the total thickness.

(4) No melting throughout the entire thickness.

(5) There shall be no afterflame for 30 seconds or more after heating is completed.

(6) The temperature time area tdθ of the part of the exhaust temperature curve exceeding the standard temperature curve shall be 100 or less.

(7) Smoke generation coefficient CA = 60 or less.

Figure 5 shows the results measured in accordance with the provisions (6) and (7) of the Ministry of Construction Notification No. 1231, and is shown in comparison with the standard temperature curve (indicated by the broken line). As shown in the figure, the exhaust temperature P versus the heating time t (minutes) on the horizontal axis
[°C] is significantly below the standard temperature curve at t≒4 or less, and even at t>4 the temperature time area tdθ≒11.25 is extremely small and clears the above regulation (6). . Also, smoke generation coefficient CA=
It is 0.6, which is significantly lower than the standard value CA=60.

FIG. 2 is an explanatory diagram illustrating the manufacturing process of the above sound absorbing board A for ceilings. In the figure, numeral 5 is a raw material tank, 6
is an agitator, 7 is a paper stock supply pipe, 8 is a papermaking tank, 9 is a papermaking jig, 10 is a papermaking cylinder, 11
is a drain pipe, 12 is an on-off valve, 13 is a dryer, 14 is a hot air supply pipe, 15 is a hot air diffusion plate, 16 is a dehydrating type,
17 is an air valve, and 18 is a vacuum valve.

The stock 19 in the raw material tank 5 is prepared as follows. First, a phosphoric acid esterifying agent solution is prepared by dissolving several percent of urea in an aqueous solution containing ammonium polyphosphate obtained by reacting urea and phosphoric acid, and pulp is introduced into this esterifying agent solution and impregnated. After standing for a predetermined time, the pulp is pulled out of the esterifying agent solution and squeezed to dry.
Then, heat to the esterification reaction temperature (140℃),
After the reaction, a phosphoric acid esterified pulp is obtained by cooling and washing with water.

On the other hand, as the inorganic fiber, glass fiber is used as the second material, and this glass fiber is a fiber bundle subjected to strand treatment, and the fiber diameter is about 7 μm and the fiber length is 2 mm.
Use a moderate amount.

The blending ratio of the above two types of materials is as follows.

First material Esterified fiber 60% weight Second material Strand glass fiber 40% weight The above materials are charged into a beating machine in the order of esterified pulp fiber and strand glass fiber. In particular, strand glass fibers are defibrated so as not to damage their fiber morphology, and adjusted to a predetermined degree of beating, approximately 30°SR. In order to improve the wet strength of the defibrated paper stock, a sticky water-soluble substance made of thermosetting resin is added to the paper stock at an absolute dry ratio of 3% to 4%, and the resin is added to the paper stock on the acidic side using aluminum sulfate. Fix it in the food. The stock 19 thus obtained is adjusted to have a density of 2.5 g/g/.

This stock 19 is supplied to the papermaking tank 8 from the stock supply pipe 7. In the papermaking tank 8, a papermaking jig 9 (a papermaking net made of punched metal in the shape of a sound-absorbing plate A) is immersed in the paper stock 19.
When dehydrated by the paper making cylinder 10, the paper stock 19 is made into the shape of the paper making jig 9. At this time, as shown in FIG. 3, the paper stock 19 becomes dense near the outer surface of the paper making tool 9, and becomes coarser as it moves away from the outer surface. After dehydrating until the moisture content reaches 60 to 65%, set the sound absorbing plate A in the dehydrating type 16 of the dryer 13, blow 100°C hot air from the hot air supply pipe 14, and blow the vacuum pump from the bottom of the dryer 13. Dry by suction using P at a vacuum pressure of 450 mmHg or more.

The inner surface 4a on the side of space B is a surface that comes into direct contact with the outer surface of the paper making tool 9 during papermaking, and also a surface that comes into direct contact with the outer surface of the dehydration mold 16 during drying, and is a surface that directly contacts the outer surface of the dehydration mold 16 during papermaking, and is a surface that directly contacts the outer surface of the dehydration mold 16 during papermaking. The density can be made larger than that of the outer surface 4b by the suction force of the hot air. Note that the peripheral edge portion 1 is molded by pressurizing with a press pressure of 6 kg/cm ² .

In this way, the ceiling sound absorbing board A shown in FIGS. 1a and 1b can be manufactured.

FIG. 4 is a graph showing the measurement results of the sound absorption coefficient using the reverberation room method according to JIS-A-1409. The dimensions and density of the ceiling sound absorbing board A used in this measurement are as follows.

Vertical and horizontal dimensions...606mm x 606mm Thickness...4mm to 6mm Density of surface 4a...0.30g/cm ³ sides 4b 〃...0.154g/cm ^2For comparison, a flat plate with vertical and horizontal dimensions of 606mm x 606mm and a thickness of 4mm to 6mm Similar measurements were made for a sound absorbing board of the same size (comparative example) and a sound absorbing board with an air layer of 300 mm on the back surface (comparative example), and the results are also shown in Figure 4.

As is clear from FIG. 4, the sound absorption board A for the ceiling has a sound absorption coefficient equal to that of the back air layer of 300 mm.

As explained above, according to the sound absorbing board for a ceiling of the present invention, a fiber material made of a mixture of esterified pulp fiber and glass fiber is made into a paper, and a side plate part is integrally provided on the periphery of the ceiling part, And since the density of the surface on the side of the space surrounded by the ceiling part and the side plate part is made larger than the density of the surface on the opposite side,
It is lightweight, there is no need to worry about loading, and in addition to having a large apparent area, the gaps and density between the fibers inside the sound absorbing board change, so the same sound absorption coefficient can be obtained without providing a back air layer. , good workability.

In addition, it has mechanical strength and is difficult to deform, and in addition to being able to place lighting equipment in the space surrounded by the ceiling and side panels, it is also possible to lock cords and the like to the surface on the side of this space.

In addition, it can be used as a ceiling material in halls, lobbies, conference rooms, etc. to achieve a sculptural beauty, and it can be used as a ceiling material with a variety of variations and three-dimensional dynamic designs that are almost impossible with conventional ceilings. I can do it.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1A is a plan view, FIG. 1B is a sectional view, FIG. The figure is a graph showing sound absorption coefficient, and FIG. 5 is a graph showing flame retardancy. 1...Peripheral part, 2...Central part, 2a...Ceiling part, 2b...Side plate part, 4a, 4b...Surface, B...
space.

[Claims]

1. Attach each bundle to the roof beam of a double parting wall where the parting walls of the building are parallel to each other with a small gap, and install purlin joint hardware between the upper surfaces of both bundles, and attach the purlin joint hardware to each bundle. A roof frame made by fixing the main buildings of adjacent buildings to both ends of the main building joint metal fittings.