JPH0367150B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to asphalt roofing for use in waterproofing structures such as high-rise buildings, expressways, bridges, subways, etc., where the underlying structure undergoes significant movement and requires complete waterproofing and durability. Asphalt roofing is used for waterproofing structures where the underlying structure undergoes significant movement, such as high-rise buildings, and is known to use non-woven fabric as a reinforcing material, impregnate and cover with asphalt, and then sprinkle mineral powder. ing. In order to perfect the waterproofness and durability of asphalt roofing, physical properties such as tensile strength and 3% tensile stress are specified by JIS (see JIS-A6022).
I started to do that. However, simply the above
Merely satisfying JIS standards was insufficient for performance for high-rise structures. In other words, the above JIS standard specifies the tensile strength, elongation rate at maximum load, 3% tensile stress, and tensile product regarding the tensile performance of asphalt roofing. This is caused by the cracks that occur in the base of the structure expanding, and the repeated expansion and contraction movement of the cracks causes the displacement to be applied as strain to the asphalt roofing where the crack occurs, and the displacement energy of high-rise structures is extremely large. , No matter how large the 3% tensile stress or tensile strength of asphalt roofing is set, it cannot overcome the energy of structural displacement, and the initial modulus against tension is increased in order to reduce the amount of strain in the waterproof layer. However, the displacement applied to the waterproof layer is given as the amount of strain that correlates to the amount of displacement of the underlying layer, so if the amount of strain exceeds the elongation at break of this waterproofing material, it is meaningless.
Stress only appears as a resistance force that deforms the waterproof material, and as long as its elongation is small, it cannot escape destruction. Moreover, the above JIS standards are
3% tensile stress of 6 kg/cm or more in the longitudinal direction and 4 in the width direction
kg/cm or more, and the tensile strength is 12 kg/cm in the longitudinal direction.
cm or more and the width direction is 8Kg/cm or more, the tensile product is 10Kg/cm or more in both the longitudinal and width directions, and the elongation at maximum load is 6% or more in the longitudinal direction and 9% in the width direction. % or more, and the lower limits of tensile product and elongation at maximum load are lower than the lower limits of 3% tensile stress and tensile strength, so they can withstand large movements of the substrate and are as described above. Therefore, it is not possible to obtain a superior waterproofing material that is resistant to severe damage. Asphalt roofing is a composite of an asphalt layer and a reinforcing material, and there are two types: a homogeneous type in which asphalt is homogeneously contained in the reinforcing material, and an adhesive type in which the asphalt layer is adhered to one or both sides of the reinforcing material. Type, reinforced core type, etc. are known. However, when the asphalt layer is unevenly distributed, such as the adhesive type or reinforced core type, when the crack width in the base of the structure expands, shearing force acts on the unevenly distributed asphalt layer against the reinforcing material, resulting in shearing. Deformation strain occurs, and the reinforcing material behaves in the same way as the asphalt layer adhered to the base, and the reinforcing material is not effective, and the unevenly distributed asphalt layer becomes easily destroyed, and the reinforcing material does not sufficiently cover the asphalt. Alternatively, if the reinforcing material does not have waterproof ability due to insufficient inclusion, the waterproof layer is likely to be destroyed, and the durability will be lower than that of a homogeneous type reinforced by homogeneously containing asphalt, which is a waterproofing material, in the reinforcing material. Therefore, the reinforcing material needs to have enough bulk to sufficiently impregnate asphalt and not cause delamination. Furthermore, the manufacturing process for asphalt roofing generally involves dipping reinforcing material into molten asphalt at a high temperature of about 200 to 230 degrees Celsius, squeezing it, placing asphalt on top, and sprinkling iron sand, etc., to create a product. Normal and machining speed is 30m/
It is often set to min or higher. Therefore,
In addition to the above-mentioned required properties, the reinforcing material must also have the ability to withstand heat shrinkage and processing tension under the above-mentioned processing conditions, and to resist elongation deformation. This invention has high tensile strength and elongation at break, with a tensile strength of 12 kg/cm or more in the longitudinal direction and 8 kg/cm or more in the width direction, and an elongation at maximum load in the longitudinal direction.
30% or more, 35% or more in the width direction, the asphalt is uniformly impregnated into the reinforcing material, and there is no delamination of the reinforcing material, resulting in excellent waterproofness and durability. The present invention provides a good asphalt roofing that has a low thermal shrinkage rate at the bottom, can withstand processing tension, has good dimensional stability, does not have width intrusion, and has little dimensional change due to heat and stress relaxation of the product. That is, this invention provides asphalt roofing in which a nonwoven fabric is impregnated and coated with asphalt as a reinforcing material. In addition, the contact point of the polyester filament is bonded with an adhesive, and the needle density of the needling is set to 30 to 130 times/cm ² ,
The above adhesive is a thermosetting resin, or an adhesive made of a combination of a vinyl or acrylic adhesive with crosslinking ability and a thermosetting resin, and the solid content of the adhesive is 15 to 31% by weight. %, an apparent density after dry heat treatment of 0.1 to 0.25 g/cm ³ , and a 5% tensile stress in the longitudinal direction at 200° C. of 2.5 Kg/5 cm or more. The nonwoven fabric of the present invention is made of polyester filament, which is a synthetic fiber with excellent heat resistance, in order to avoid heat shrinkage and widening during processing. The preferred thickness of this polyester filament is 3
~25 denier. If the thickness is less than 3 deniers, the tear strength decreases, the voids in the nonwoven fabric become small, the bulkiness decreases, the amount of asphalt impregnated becomes insufficient, and the waterproofness decreases. On the other hand, if it exceeds 25 denier, the number of adhesive points in the nonwoven fabric will decrease, resulting in insufficient tensile strength. The above polyester filament needs to be formed into a textured web with a random loop structure in order to increase the elongation at break and eliminate the directionality of the strength and elongation. It is formed by a known method, for example, the spunbond method described in Japanese Patent Publication No. 53-32424.
The nonwoven web is then mechanically entangled by needling and bonded with an adhesive, resulting in a nonwoven web with high tensile strength and elongation at break, non-directional, and high bulk. formed into a large non-woven fabric. The nonwoven web described above may be formed not only by the spunbond method described above but also by a method in which spun and drawn polyester filaments are deposited in a random loop structure. The practically preferable basis weight of the nonwoven web is 60 to 300 g/m ² ,
In particular, it is 80 to 200g/ ^m2 , and this area weight is 60g/m2.
If it is less than m ² , it will be difficult to obtain the physical properties necessary as a reinforcing material for asphalt roofing. Needling to mechanically intertwine the nonwoven web is performed to impart appropriate bulk and to prevent delamination of the nonwoven web.
The needle density for this needling varies depending on the shape and insertion depth of the needling needle, but it is between 30 and 130.
It is set within the range of times/ ^cm2 . The needle density above is 30
If it is less than 2 times/cm ² , entangling is insufficient and various physical properties, especially modulus at heat and elongation at break, are insufficient, and delamination is likely to occur, and in particular, the product has low delamination resistance. On the other hand, if the needle density exceeds 130 times/cm ² , the amount of filament breakage due to needling will increase, and various physical properties will deteriorate.
This is also disadvantageous in terms of man-hours. In the present invention, it is important to further apply an adhesive to the needled nonwoven web to bond the polyester filament contacts, thereby increasing the thermal dimensional stability and Young's modulus.
As for the adhesive to be used, it is preferable to use one having a high modulus and a large adhesive force because the effect can be obtained with a small amount. Examples include adhesives made of thermosetting resins, that is, thermosetting adhesives, and adhesives consisting of a combination of vinyl or acrylic adhesives having crosslinking ability and thermosetting resins. Examples include urea resin systems, melamine resin systems, urea/melamine cocondensation resin systems, epoxy resin systems, unsaturated polyester resin systems, and mixed systems thereof. The above-mentioned adhesive is impregnated into the above-mentioned nonwoven web in liquid form according to a conventional method, and
After squeezing the liquid if desired, it is dried and baked. Usually, it is preferable to use a curing catalyst in combination to accelerate the curing reaction. Note that a vinyl or acrylic adhesive having crosslinking ability can be used in combination with the above thermosetting adhesive. For example, it is a combination of a self-crosslinking acrylic resin adhesive and a urea resin initial condensate, a melamine resin initial condensate, an epoxy compound, or formalin, glyoxal, etc. used for anti-wrinkle processing of fibers. Furthermore, a combination of PVA and a fiber processing agent such as the above-mentioned urea resin initial condensate, formalin, glyoxal, etc. is also possible. However, since the effect differs depending on the crosslinking density, it goes without saying that the amount of functional groups in the main adhesive, the amount of crosslinking agent, the amount of catalyst, baking conditions, etc. should be appropriately selected. The solids content of the adhesive is 15-31% by weight. As the amount of adhesive adhered increases, the number of adhesive points increases, and the tensile strength of the nonwoven fabric itself tends to increase. However, the tensile strength of asphalt roofing is not necessarily proportional to this, and the above-mentioned solid content adhered above a certain amount As the tensile strength of the asphalt roofing increases, the tensile strength of the asphalt roofing conversely decreases or levels off. That is, if the solid content above is 15
If it is less than % by weight, not only will it be impossible to obtain the required physical properties, but also the process of impregnating the nonwoven fabric with molten asphalt at 200 to 230°C will cause width loss, impairing the appearance, and may cause shrinkage and uneven processing. etc., resulting in uneven physical properties. Lowering the temperature of the molten asphalt may be considered to prevent the above-mentioned widening, but in this case, the melt viscosity increases, which reduces the asphalt's ability to impregnate the nonwoven fabric (reinforcing material), making uniform impregnation difficult. Become. Also,
The increase in melt viscosity causes insufficient mixing and agitation of the molten asphalt by the running reinforcing material, which impairs uniform asphalt impregnation, and also causes local differences in thermal history in the reinforcing material itself, resulting in non-uniform products. In order to achieve uniform impregnation, it is necessary to extend the soaking time, lengthen the soaking tank, and strengthen the traction force of the reinforcing material running in the soaking tank, which may have the opposite effect. be. Conversely,
If the solid content of the adhesive exceeds 31% by weight, the tensile strength of the asphalt roofing will decrease, and this will be economically disadvantageous. The apparent density of the reinforcing material obtained above is
0.1 to 0.25 g/cm ³ , particularly 0.12 to 0.19 g/cm ³ is preferred. If the above apparent density is less than 0.1g/ ^cm3 ,
If the bulkiness becomes excessive and the amount of asphalt impregnated into the reinforcing material is too large, the product basis weight becomes larger than necessary.On the other hand, if it exceeds 0.19g/ ^cm3 , the asphalt impregnation property deteriorates, so homogeneous type Homogeneity decreases as asphalt roofing. Furthermore, the stress of the reinforcing material at 5% elongation in the longitudinal direction at 200° C. must be at least 2.5 kg/5 cm. In other words, the stress-elongation curve of the reinforcing material is almost a straight line in the range of elongation of 5% or less,
The processing tension during impregnation with molten asphalt at 200℃ is generally about 10Kg/m (0.5Kg/5cm), so the stress at 5% elongation in the longitudinal direction is 2.5.
This is because if it is less than Kg/5cm, the elongation rate in the longitudinal direction of the reinforcing material due to the working tension during asphalt impregnation exceeds the permissible limit of 1%. In addition, the elongation rate in the longitudinal direction during asphalt impregnation is 1%.
When it exceeds , the dimensional stability of the asphalt roofing will be insufficient during construction of the waterproof roof or during long-term use after construction. In addition, the area weight of the reinforcing material is preferably 80 g/m ² or more, particularly 100 to 250 g/m ² . The above-mentioned reinforcing materials are usually produced by impregnating and covering with asphalt and scattering mineral powder using a conventional method, but they are also manufactured by impregnating and covering with rubber asphalt and wrapping it with paper, film, etc. It can also be commercialized. The physical properties of the obtained asphalt roofing are as follows: elongation at maximum load is 30% or more, 3% tensile stress is 0.03Kg/cm・(g/m ² ) or more in the longitudinal direction, and 0.02Kg/cm・(g/m 2 ) in the width direction. ^m2 ) or more, tensile strength is 0.08Kg/cm・(g/ ^m2 ) or more in the longitudinal direction, 0.05 in the width direction.
Kg/cm・(g/m ² ) or more, tensile product is 0.2 in the longitudinal direction
Kg・cm/(g/m ² ) or more, preferably 0.25Kg・
cm/(g/ ^m2 ) or more, width direction 0.15Kg・cm/(g/m2) or more
^m2 ) or more, preferably 0.20Kg・cm/(g/ ^m2 ) or more, 200℃ heat shrinkage rate of 0.4% or less in the longitudinal direction, width direction
It is less than 0.2% and can be used in structures where the underlying structure undergoes severe movement, such as high-rise buildings, and can withstand long-term use without breaking even if cracks occur in the underlying structure. In addition, in order to clarify the reinforcing efficiency of each reinforcing fabric and to facilitate relative comparison, the dimensions used to display the product physical property values above are expressed as the basis weight (g) of the reinforcing fabric used in its manufacture. /m ² ) and displayed. Next, the effects of this invention will be explained with reference to Examples. Note that the physical properties were measured in accordance with the following. (1) Physical properties of non-woven fabric Testing shall be conducted in accordance with the "Synthetic Fiber Non-woven Fabric Test Method" established by the Japan Chemical Fibers Association below. (a) Fabric weight (mass per unit area) A. Size of the sample 1 m x 1 m B. Number of samples 1 piece per 1 m width C. Measurement method Bring the sample to moisture equilibrium and measure the mass. (b) Stress at 5% elongation and Tensile strength, elongation rate (a) Sample size: 5cm x 20cm (b) Number of samples: 3 pieces each (vertical and horizontal) per 1m width (c) Measurement method: According to JIS L1096 (general textile testing method),
Using a constant speed extension type tensile tester, grip width
10cm, pulling speed 20±2cm per minute,
Read the stress, tensile strength, and elongation rate at 5% elongation from the chart. D. Display of results Calculate the average value for each vertical and horizontal direction. Stress and tensile strength during elongation are Kg/5cm
Displays units to one decimal place. The elongation rate is displayed to the nearest integer in %. (C) Tear strength (pendulum method) A. Size of sample 6.5cm x 10cm B. Number of samples 3 pieces each vertically and horizontally per 1m width. C. Measurement method: Using an Elmendorf type tear tester,
Make a 2cm cut with a sharp knife at the center of both grips of the sample, at right angles to the long side, and measure the maximum load when the remaining 4.5cm is torn. D. Displaying the results Calculate the average values for each of the vertical and horizontal directions,
Display to one decimal place in kg. (Note) To distinguish between vertical and horizontal tearing, tearing the nonwoven fabric in the vertical direction is referred to as "vertical tearing." (2) Measurement of physical properties of asphalt roofing (a) Stress, tensile strength, and elongation rate at 5% elongation are
It was measured and evaluated using the measurement method specified in JIS A6022. (b) Fatigue test JASS 8.Reference materials 1. Test method for membrane waterproof layer Conducted based on "6. Fatigue test". however,
Regarding the display of results, we found that the size classification of movements used in the test process did not cause any change in the waterproof layer within the range specified by JASS 8. 5.0~10.0mm) = [6 steps]
A new test process was established and the test was conducted, and the pass/fail of each process was indicated by grade. Example According to the method described in Japanese Patent Publication No. 53-32424, polyethylene terephthalate with an intrinsic viscosity of 0.62 was extruded at 290°C through a nozzle having multiple orifices with a diameter of 0.3 mm and a length of 0.6 mm, and the spinning speed was 5300 m/min.
The fibers were pulled to a fineness of min. min, and then deposited in a uniformly dispersed manner on a moving wire mesh conveyor equipped with a suction device at the bottom to obtain a long fiber nonwoven fleece with a randomly arranged structure. The basis weight of the fleece is adjusted by the number of holes in the discharge nozzle, the amount of extrusion, and the running speed of the wire mesh conveyor. Pass the above fleece through a needle punching machine, and use a felting needle FPD-1-40 manufactured by Organ Co., Ltd. to a depth of 14 mm and a needling density of 30 to 130.
Needling was performed at a rate of twice/cm ² , further immersed in an adhesive emulsion, squeezed, dried, and baked at 170° C. to complete the crosslinking and curing reaction to obtain a reinforcing nonwoven fabric. The adhesives used were 30 parts of urea resin (manufactured by Sumitomo Chemical Co., Ltd., trade name "Sumitex Resin H-90"), trimethoxymethyl melamine (manufactured by Sumitomo Chemical Co., Ltd., trade name "Sumitex Resin H-90"), M-3'') 5 parts, hard type cross-linked acrylic acid ester polymer latex (manufactured by Rohm & Haas Co., Ltd., trade name ``Primal HA-16'') 64 parts, and propanolamine hydrochloride salt system Catalyst (manufactured by Sumitomo Chemical Co., Ltd.,
Product name “Sumitex Accelerator ACX”) 1
It consists of several parts. Next, the above nonwoven fabric
210℃ according to the manufacturing method shown in JIS-A-6022
The asphalt roofings of Examples 1 to 8 were produced by coating the molten asphalt with an impregnating content of about 800 g/m ² and further scattering mineral powder. The basic composition of the nonwoven fabric is shown in Table 1, the physical properties of the nonwoven fabric are shown in Table 2, and the physical properties of the product are shown in Table 3. Note that the formulation of the adhesive was the same. Furthermore, in Tables 2 and 3, T indicates the longitudinal direction and W indicates the width direction, respectively. Furthermore, in Table 3, the evaluation of dimensional changes during asphalt roofing processing was performed using nonwoven fabrics at 210°C.
Asphalt roofing is manufactured by impregnating molten asphalt at a running speed of 30 m/min using a conventional method, and the width of the resulting product is as follows:
The width change rate was measured, and those less than 1% were rated ◎, those 1% or more and less than 2% were rated O, and those 2% or more were rated ×. However, the width change includes both heat shrinkage and change strain due to processing tension.

【table】

【table】

[Table] On the other hand, Comparative Examples 1 to 8 were prepared by using the same long fiber nonwoven fleece with a randomly arranged structure as in Examples 1 to 8 above, and changing the needling conditions, adhesive formulation, amount of solid content, etc. Obtained 7 Asphalt Roofing. The basic composition of the nonwoven fabric is shown in Table 4, the physical properties of the nonwoven fabric are shown in Table 5, and the physical properties of the product are shown in Table 6. In addition,
In the adhesive formulation, A is the same as in Examples 1 to 8, and B is a soft type acrylic ester polymer latex (manufactured by Rohm & Haas Co., Ltd., trade name "Primal HA-8").
94 parts and trimethoxymethylmelamine (manufactured by Sumitomo Chemical Co., Ltd., trade name "Sumitex Resin M")
-3"), and 1 part of a propanolamine hydrochloride catalyst (manufactured by Sumitomo Chemical Co., Ltd., trade name "Sumitex Accelerator ACX"). In addition, the needle for needling is Example 1
The same material as in ~8 was used.

【table】

【table】

【table】

[Table] As is clear from a comparison of Tables 1 to 6 above, nonwoven fleece with a random structure made of polyester filaments has a needle density of 30 to 130 times/cm ²
Needled with adhesive, and further adhesive solids content of 15 to 31% by weight with adhesive mainly composed of thermosetting synthetic resin.
The asphalt roofings of Examples 1 to 8, in which the resulting nonwoven fabric was used as a reinforcing material, had high tensile strength, high elongation, and high modulus. It has excellent dimensional stability against force and dimensional stability against heat.
On the other hand, comparative example 1 in which needling was omitted
In the asphalt roofings of ~3, although other conditions such as adhesion conditions were almost the same as Examples 1 to 8, the apparent density of the nonwoven fabric was too high,
The elongation and tensile product at maximum load of the product are low, the apparent density is large, and the impregnating property of asphalt is poor.
The resulting roofing is not a homogeneous type, causing delamination between layers, resulting in a roofing that lacks durability. In addition, in Comparative Example 4, in which the adhesive formulation was changed and an adhesive based on a soft acrylic ester polymer was used instead of a thermosetting synthetic resin, the stress at 5% elongation at 200°C of the nonwoven fabric was Because it is too small,
It cannot withstand the processing tension of the asphalt roofing manufacturing process, and the width is significantly increased during processing, resulting in poor thermal dimensional stability of the product. Also, Comparative Example 5
Although needling was performed and an adhesive with the same formulation as in the example was used, the dimensional stability against heat was poor as in Comparative Example 4 because the amount of solid content deposited was small. Furthermore, in Comparative Example 6, the needling needle density was too high, so fiber breakage occurred during needling, resulting in a decrease in the tensile strength and tensile product of the product. Furthermore, in Comparative Example 7, the needling needle density was insufficient, so the intertwining of the nonwoven web was insufficient, resulting in a product with poor physical properties.

Claims (1)

[Scope of Claims] 1. In asphalt roofing in which a nonwoven fabric is impregnated and coated with asphalt as a reinforcing material, the nonwoven fabric is mechanically formed into a nonwoven web with a random structure made of polyester filaments by needling. At the same time, the contact points of the polyester filaments are bonded together with an adhesive, the needle density of the needling is set at 30 to 130 times/ ^cm2 , and the adhesive is a thermosetting resin, or It is an adhesive consisting of a combination of a vinyl or acrylic adhesive with crosslinking ability and a thermosetting resin, and the solid content of the adhesive is 15 to 31% by weight, and the apparent density after dry heat treatment is
0.1-0.25g/cm ³ , 5% in the longitudinal direction at 200℃
Asphalt roofing characterized by a tensile stress of 2.5Kg/5cm or more. 2 The thickness of the polyester filament is 3 to 25 deniers, and the fiber basis weight of the nonwoven fabric is 60 to 300.
Asphalt roofing according to claim 1, which is g/m ² . 3 Elongation at maximum load after asphalt processing is 30%
Above, the 3% tensile stress is 0.03Kg/cm in the longitudinal direction.
(g/m ² ) or more, width direction 0.02Kg/cm・(g/m ² ) or more, longitudinal direction tensile strength 0.08Kg/cm・(g/m ² )
or more, the width direction is 0.05Kg/cm/(g/m ² ) or more, the longitudinal direction is 0.2Kg/cm/(g/m ² ) or more, the width direction is 0.15Kg/cm/(g/m ² ) or more The asphalt roofing according to claim 1 or 2, wherein the asphalt roofing has a heat shrinkage rate of 0.4% or less in the longitudinal direction and 0.2% or less in the width direction at 200°C.