JP2000158572A - Weatherable protective material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a water-barrier sheet over a long period by improving its weatherability by forming a resin layer on one side of a long fiber nonwoven fabric of at least specified METSUKE having three-dimensional interlacing structure by needle punching. SOLUTION: A mixed resin liquid is prepared by mixing 100 pts.wt. of an aqueous emulsion resin such as an acrylic resin, a urethane resin, and a rubber latex resin and 1-30 pts.wt. of a foam conditioning agent. Next, the mixed resin liquid is agitated/foamed while air is introduced into the liquid, and the foamed resin liquid is applied on one side of a long fiber nonwoven fabric of at least 100 g/m2 METSUKE having three-dimensional interlacing structure by needle punching and dried to form a resin layer containing a benzotriazole or benzophenone ultraviolet absorbent. In this way, a water-barrier sheet can be protected over a long period by improving its abrasion resistance, durability, weatherability, and others.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective material used in the field of civil engineering requiring weather resistance.

[0002]

2. Description of the Related Art Waterproof sheets are used on the bottom and slopes of reservoirs, waste disposal sites, etc., and to prevent defects in the waterstop sheet due to falling objects or ground protrusions. A long-fiber nonwoven fabric is laid on the waterproof sheet to protect the waterproof sheet.

However, the long-fiber nonwoven fabric used as a protective material for the water-stop sheet is usually made of a thermoplastic synthetic polymer and does not have sufficient weather resistance. The nonwoven fabric itself deteriorated and could not function as a protective material for a long time.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a protective material which has high weather resistance and functions effectively to protect the water-stop sheet for a long period of time. Is what you do.

[0005]

According to the present invention, there is provided a long-fiber nonwoven fabric having a basis weight of 100 g / m ² or more having a three-dimensional entangled structure formed by a needle punch treatment. The present invention is directed to a weather-resistant protective material characterized by being provided with:

[0006]

Embodiments of the present invention will be described below. The long-fiber non-woven fabric used in the present invention is effective for achieving the object of the present invention because the fibers constituting the non-woven fabric are composed of continuous fibers, and thus have higher strength than the short-fiber non-woven fabric. .

The present invention is a weather-resistant protective material comprising a long-fiber nonwoven fabric provided with a resin layer on at least one surface. By providing a resin layer on at least one side of the long-fiber nonwoven fabric,
Since the amount of sunlight reaching the nonwoven fabric decreases, deterioration of the nonwoven fabric is prevented, and the abrasion resistance of the protective material is improved, so that the waterproof sheet can be protected from falling objects and the like.

Examples of the method for providing a resin layer on one side of a long-fiber nonwoven fabric include a method of laminating a film to a long-fiber nonwoven fabric, a foaming method of applying a foamed resin liquid to the nonwoven fabric, and drying, a vinyl acetate system, and polyethylene. -Based, polypropylene-based synthetic resin particles dispersed on the surface of the nonwoven fabric,
A powder processing method of melting the synthetic resin by heat and fixing the synthetic resin to the surface of the non-woven fabric at the same time is exemplified. As the foam processing method, specifically, 100 parts by weight of an aqueous emulsion resin such as an acrylic resin, a urethane-based resin, and a rubber-based latex resin and 1 to 30 parts by weight of a foam stabilizer are mixed to prepare a mixed resin liquid. Subsequently, the resin liquid is stirred and foamed while blowing air, and the foamed resin liquid is applied to one surface of the nonwoven fabric and dried to form a resin layer. Also, by penetrating the applied resin liquid from one side of the nonwoven fabric to about 1/3 of the thickness of the nonwoven fabric, the nonwoven fabric and the weather-resistant resin layer can be joined well, and the peeling resistance can be improved.

The resin layer preferably has water permeability. By making it water-permeable, rainwater can be promptly guided to the long-fiber nonwoven fabric layer without leaving a pool on the surface of the protective material. Further, the long-fiber nonwoven fabric layer functions as a drainage layer and can quickly discharge rainwater.

[0010] The water-permeable resin layer has a microporous structure in which innumerable micropores are distributed as if scattered on the surface and inside of the layer, and at least a part thereof is connected to each other continuously or intermittently. Preferably, there is. In other words, the microporous structure referred to here means that some of the micropores are connected by pores,
The whole is a state in which the micropores in the layer surface and the inside of the layer are continuous, and has air permeability or water absorption.
A water-permeable resin layer having a microporous structure can be obtained by the foaming method or the powder processing method described above.

The basis weight of the resin layer (in the foaming method and the powdering method, based on the weight of the solid content after drying) is 50 g.
/ M ² or more. When the amount is 50 g / m ² or more, sufficient weather resistance and wear resistance can be imparted to the protective material. On the other hand, the upper limit is 300 g / m
² is the degree.

In the present invention, the resin layer preferably contains a benzotriazole-based or benzophenone-based ultraviolet absorber. These UV absorbers
It functions to absorb the ultraviolet rays in the polymer constituting the resin layer and prevents the polymer from being deteriorated by the ultraviolet rays.

Examples of the benzotriazole-based ultraviolet absorber include 2- (5-methyl-2-hydroxyphenyl) benzotriazole and 2- [3,5-bis (2,
2'-dimethylpropyl) -2-hydroxyphenyl]
Benzotriazole, 2- (3-tert-butyl-5)
-Methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methylenebis [4- (1,
1 ', 3,3'-tetramethylbutyl) -6- (2H-
Benzotriazol-2-yl) phenol], 2-
(2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-tert)
-Butylphenyl) benzotriazole, 2- (2'-
Hydroxy-3 ′, 5′-di-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-
3'-tert-butyl-5'-methylphenyl) -5
-Chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5
Chlorobenzotriazole, 2- (2'-hydroxy-
3 ', 5'-di-tert-amylphenyl) benzotriazole, 2- [2'-hydroxy-3'-
(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl] benzotriazole. Among these, 2- [2
-Hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2 ′
-Methylenebis [4- (1,1 ', 3,3'-tetramethylbutyl) -6- (2H-benzotriazole-2-
Il) phenol] is preferable because of its excellent heat resistance.

As the benzophenone type ultraviolet absorber,
For example, 2,4-dihydroxybenzophenone, 2,2
2 ', 4,4'-tetrahydroxybenzophenone, 2
-Hydroxy-4- (β-hydroxyethoxy) -benzophenone, bis (5-benzoyl-4-hydroxy-
2-methoxyphenyl) methane, 2-hydroxy-4-
Methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy -4,4-dimethoxybenzophenone and 2-hydroxy-4-methoxy-5-sulfobenzophenone. Among these, bis (5-benzoyl-4-hydroxy-
2-Methoxyphenyl) methane is preferable because of its excellent heat resistance.

Further, the resin layer in the present invention preferably contains 0.01 to 3.0% by weight of a hindered amine-based, hindered phenol-based or phosphorus-based antioxidant. Antioxidants function to prevent thermal oxidation of the polymer caused by animal heat and oxygen present during outdoor use.

As the antioxidant used in the present invention, for example, triethyl glycol-bis [3- (3-tert)
-Butyl-5-methyl-4-hydroxyphenyl) propionate], 4,4'-thiobis- (3-methyl-6
-Tert-butylphenol), 2,2′-methylenebis- (4-methyl-6-tert-butylphenol), 2,2′-ethylidene-bis- (4,6-di-t
tert-butylphenol), tris- (3,5-di-
tert-butyl-4-hydroxybenzyl) -isocyanurate, tris- (2-methyl-4-hydroxy-
5-tert-butylphenyl) butane, 2,6-di-
tert-butyl-p-cresol, butylated hydroxyanisole, (BHA), 2,6-di-tert-butyl-4-ethylphenol, stearyl-β- (3,
5-di-tert-butyl-4-hydroxyphenyl)
Propionate, 2,2'-methylene-bis- (4-ethyl-6-tert-butylphenol), 4,4'-
Butylidene-bis- (3-methyl-6-tert-butylphenol), 1,3,5-trimethyl-2,4,6
-Tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3
-(3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate] methane, bottle (3,
3'-bis- (4'-hydroxy-3'-tert-butylphenyl) butyric acid) glycol esters and tocophenols.

As a method for incorporating these ultraviolet absorbers and antioxidants into the resin layer, they may be mixed into a resin liquid as a material of the resin layer. Further, a binder containing an ultraviolet absorber or an antioxidant may be provided by coating or dipping.

The constituent polymer of the long-fiber nonwoven fabric used in the present invention may be a fiber-forming thermoplastic synthetic polymer, for example, a polyester-based polymer such as polyethylene terephthalate or polybutylene terephthalate, or a polymer thereof. An acid component such as phthalic acid, isophthalic acid, glutaric acid, adipic acid, diethylene glycol, propylene glycol, 2,2-bis (4-hydroxyethoxyphenyl) propane, bisphenol A, 1,4
-Copolyesters obtained by copolymerizing diol components such as butanediol and the like, polyolefin polymers such as polyethylene and polypropylene, nylon 6, nylon 66
Polyamide polymers such as polyamides, polyvinyl alcohol polymers represented by vinylon, and the like are used, and fibers composed of these polymers alone, or laminated composite fibers obtained by combining two or more different polymers, cores Any of the sheath type composite fibers can be used.

The basis weight of the long-fiber nonwoven fabric is 100 g / m ² or more. In the present invention, since a long-fiber nonwoven fabric having a high basis weight is used, abrasion resistance, durability, weather resistance, and the like are improved, and a protective material can be applied for a long period of time. The upper limit of the basis weight of the long-fiber nonwoven fabric is not particularly limited, and may be appropriately selected according to the place to be used as a protective material, environmental conditions, construction means when constructing the sheet, and the like.
/ M ² .

The single fiber fineness of the constituent fibers of the long-fiber nonwoven fabric is 2
It is preferably from 10 to 10 denier, more preferably from 3 to 7 denier. If the denier is less than 2 denier, the fibers are apt to be cut when subjected to the needle punching treatment, and the mechanical properties such as tear strength and tensile strength of the obtained nonwoven fabric are undesirably reduced. On the other hand, if the denier is larger than 10 denier, the entanglement of the fibers is not sufficiently formed, and the mechanical properties such as the tear strength of the obtained nonwoven fabric are undesirably reduced.

The long-fiber nonwoven fabric having a three-dimensional entangled structure used in the present invention is obtained by forming a web by a so-called spunbonding method and subjecting the obtained web to a needle punching process, or winding the web once to obtain a needle. By performing the punching process, a nonwoven fabric whose shape is maintained by entanglement of the constituent fibers in the thickness direction is formed. By having a three-dimensional confounding structure, mechanical strength such as tear strength is improved,
Also, since there is an appropriate gap between the fibers, rainwater can be quickly discharged.

The conditions for the needle punching treatment are not particularly limited, but a punch density of 50 to 150 pieces / cm ² is preferred because the mechanical properties of the nonwoven fabric and the entanglement between fibers are improved. When the punch density is less than 50 pieces / cm ² , the entanglement of the constituent fibers is insufficient, and the nonwoven fabric has a very weak and fuzzy nonwoven fabric without improving mechanical properties such as tear strength. When the punch density exceeds 150 pieces / cm ² , although the fibers are sufficiently entangled, the fibers are partially cut, resulting in a nonwoven fabric having poor mechanical properties such as tear strength of the nonwoven fabric. Cannot be reached, which is not preferable.

In order to further strengthen the bonding between the constituent fibers of the nonwoven fabric used in the present invention, an adhesive such as an acrylic resin is applied to improve the mechanical strength of the nonwoven fabric and the mechanical strength as a protective material. May be.

The constituent fibers of the long-fiber nonwoven fabric also contain a benzotriazole-based or benzophenone-based ultraviolet absorber in the long-fiber constituent polymer in order to provide weather resistance.
You may make it contain 01-3.0 weight%. 0.01% by weight
If it is less than 3, the effect of the ultraviolet absorber is not sufficiently exhibited, while if it exceeds 3.0% by weight, the weather resistance is saturated, which is uneconomical. Will be invited. Further, 0.01 to 3.0% by weight of an antioxidant may be contained in the constituent polymer of the long fiber.
If the content of the antioxidant is less than 0.01% by weight, the effect of the ultraviolet absorber is not sufficiently exhibited, while 3.
If the content exceeds 0% by weight, the weather resistance performance is saturated, which is uneconomical, and also leads to deterioration of the spinnability and coloring of the fibers. The total content of the ultraviolet absorber and the antioxidant contained in the constituent polymer of the long fiber is set to an amount not exceeding 6.0% by weight. When the total content exceeds 6.0% by weight,
The spinnability deteriorates, and in particular, when spinning at a speed of 2500 m / min or more, thread breakage frequently occurs. The ultraviolet absorber and the antioxidant contained in the constituent polymer of the long fiber may be the same as those contained in the resin layer.

In the protective material of the present invention, the nonwoven fabric and / or
Alternatively, a colorant may be contained in at least one of the weather-resistant resin layers. By including a colorant,
Light-shielding properties are improved, and an aesthetically pleasing product that is in harmony with the surrounding environment is obtained. The color tone of the protective material is preferably a dark color or a black color, and a green or brown color or the like may be used in order to make the aesthetic appearance excellent in harmony with the surrounding environment. Examples of the coloring agent include carbon black as black, aluminum powder and mica powder as silver gray, and iron oxide as brown. As a method for incorporating these colorants into the nonwoven fabric, the colorant may be mixed with the constituent polymer of the long fiber. In addition, as a method of including the colorant in the weather-resistant resin layer, the colorant may be mixed in a resin liquid or the like that is a material of the resin layer.

Further, in the protective material of the present invention, the nonwoven fabric and / or the weather-resistant resin layer may be provided with flame retardancy to provide a protective material having flame retardancy. In the case of protective materials with flame retardancy, for example, when laying protective materials, even if a worker passes a lit cigarette in the workplace and dumps it on the protective material, a fire will not occur. Absent.

In order to impart flame retardancy to the resin layer, a flame retardant may be mixed into a resin liquid as a material of the resin layer. Examples of the flame retardant to be mixed include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, octyl diphenyl phosphate, tris [chloroethyl] phosphate, tris [2-chloropropyl] phosphate, and tris [ 2,3-dichloropropyl] phosphate, decabromodiphenyl oxide, tricresyl phosphate, octabromodiphenyl oxide, and tetrabromophenyl oxide. In the inorganic system, barium aluminum hydroxide antimony trioxide metaborate, red phosphorus, etc. No. In addition,
If necessary, two or more of the above flame retardants may be used in combination.

In order to impart flame retardancy to the long-fiber nonwoven fabric, it is preferable to use fibers having a critical oxygen index (measured in accordance with JIS K 7201; referred to as LOI value) of 28 or more. Examples of such fibers include aramid fibers, polyphenylene sulfide fibers, carbon fibers, and phosphorus-containing polyester fibers. In the present invention, it is preferable to use a polyester fiber containing a phosphorus atom.

[0029]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. In the examples, each characteristic value was measured by the following method.

(1) Basis weight (g / m ² ): A total of 10 specimens of 10 cm long × 10 cm wide were prepared from a sample in a standard state.
After reaching the equilibrium moisture, the weight (g) of each sample piece was weighed, and the average value of the obtained values was converted per unit area (m ² ) to obtain the basis weight (g / m ² ).

(2) Bulk density (g / cc): The basis weight (g / m ² ) and thickness (mm) of the sample were measured, and the bulk density (g / cc) was determined by the following equation. Bulk density (g / cc) = basis weight / (thickness x 1000)

(3) Tear strength (kg): JIS L-1
A total of ten sample pieces were prepared and measured based on the single tongue method of No. 096.

(4) Tensile strength (kg / 5 cm width) and tensile elongation (%): Measured according to the grab method described in JIS-L-1096.

(5) Weathering resistance / strength retention (%): The protective material was exposed outdoors, the tensile strength after 5 months was measured in a standard state, and the strength retention relative to the initial value of the tensile strength before exposure ( %) Is shown by the following equation and compared. Strength retention (%) = (tensile strength after 5 months / initial tensile strength) × 100 When 70% or more of the initial tensile strength before exposure is maintained, it is considered that the weather resistance is good. evaluated.

(6) Shading ratio (%): JIS L105
It was measured by the 5A method.

(7) Afterflame time (second) and char length (c)
m): An air mix burner fixed to a test box of 45 ° micro burner method by fixing 6 samples of 22 cm × 40 cm, 3 vertical, 3 horizontal to the pearlite plate and setting the flame length to 24 mm [ Note], an indirect flame is fired for 30 seconds, the residual flame time (seconds) and carbonization length (cm) are measured, and the maximum residual flame time (seconds) and maximum carbonization length (cm) of six samples are displayed to one decimal place. did. The afterflame time was 20 seconds or less, and the carbonization length was 10
cm or less is the criteria for the Fire Service Law for flame-retardant materials. [Note] Liquefied petroleum gas No. 4 of fuel JIS K 2240 Gas pressure 0.04 kgf / cm ²

Example 1 A spunbonded nonwoven fabric made of long fibers of a polyethylene terephthalate polymer was prepared. That is, the polymer chips are melted using an extruder-type melt extruder,
After melt spinning through the spinneret and cooling the spun yarn,
After pulling and thinning using an air sucker arranged below the spinneret, the fiber is opened using a corona discharge device and collected and deposited on a screen mesh type moving collecting surface, and the single yarn fineness is reduced. A 4 denier long fiber web having a basis weight of 120 g / m ² was obtained. The obtained web was subjected to a needle punching treatment at a punch density of 90 pieces / cm ² to obtain a long-fiber nonwoven fabric having a thickness of 1.0 mm and a bulk density of 0.12 g / cc.

Next, on one side of the obtained long-fiber nonwoven fabric,
A mixed resin liquid mainly composed of an acrylic resin containing carbon black as a coloring agent was applied by a knife coater. The amounts of the carbon black and the foam stabilizer with respect to 100 parts by weight of the acrylic resin in the mixed resin liquid are as follows. 100 parts by weight of acrylic resin (Boncoat 350 manufactured by Dainippon Ink and Chemicals, Inc.) 5 parts by weight of carbon black 10 parts by weight of foam stabilizer (Boncoat F-1 manufactured by Dainippon Ink and Chemicals, Inc.) 10 parts by weight The liquid is agitated and foamed while blowing air in advance before application, and the foamed resin liquid is applied to a long-fiber nonwoven fabric and dried to form a microporous resin layer having a myriad of fine pores on the long-fiber nonwoven fabric. The protective material of the present invention was obtained. The applied amount of the mixed resin liquid was 100 g / m ^{2 in} terms of the solid content after drying.

Example 2 In Example 1, the basis weight was 800 g /
subjected to needle-punched, using those m ^2, except for using the thickness 4.0 mm, long-fiber nonwoven fabric having a bulk density of 0.1 g / cc is obtained a protective material of the present invention in the same manner as in Example 1 Was.

Example 3 As the long fiber nonwoven fabric, the long fiber nonwoven fabric used in Example 2 was used. As the resin layer, 2- (2′-hydroxy-5 ′) was added to the mixed resin liquid used in Example 1 as an ultraviolet absorber. A protective material of the present invention was obtained in the same manner as in Example 1, except that a mixed resin liquid containing 2 parts by weight of (-methylphenyl) benzotriazole with respect to 100 parts by weight of the acrylic resin was used. And

Example 4 As the long fiber nonwoven fabric, the long fiber nonwoven fabric used in Example 2 was used, and as the resin layer, the mixed resin liquid used in Example 1 was mixed with a flame retardant (Neosticker FRC-Nichika Chemical Co., Ltd.). 105)
Of the present invention was obtained in the same manner as in Example 1 except that a mixed resin solution containing 50 parts by weight with respect to 100 parts by weight of an acrylic resin was used.

[0042]

[Table 1]

The obtained protective materials of Examples 1 to 4 of the present invention are excellent in mechanical strength and weather resistance, and can be applied over a long period of time to protect the waterproof sheet. Things.

The protective material of Example 3 in which the resin layer contained a weathering agent was more excellent in weatherability.

The protective material of Example 4 in which the resin layer contained a flame retardant had high functionality with excellent flame retardancy.

[0046]

According to the weatherable protective material of the present invention, the basis weight is 1
By using a long-fiber non-woven fabric having a three-dimensional entangled structure of not less than 00 g / m ² , the wear resistance, durability, weather resistance, etc. are improved, and the light-shielding property is increased to deteriorate the water-stop sheet due to sunlight. Can be prevented. Furthermore, by providing a resin layer on at least one surface of the long-fiber nonwoven fabric, the sunlight reaching the nonwoven fabric is reduced, so that the nonwoven fabric is prevented from deteriorating. The water sheet can be protected, and the protection material can be applied for a long period of time.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08K 5/13 C08K 5/13 5/17 5/17 5/3475 5/3475 5/49 5/49 C08L 101/00 C08L 101/00 D04H 3/10 D04H 3/10 A F-term (reference) 4F100 AA37B AH02B AH02H AH03B AH03H AK01B AK25B AK42A BA02 CA06 CA06B CA07 CA07B DG04A DG15A EC09A GB90 EN13A JA13B01A00 EU197 FD056 FD077 GF00 GL00 4L047 AA21 AA29 AB03 BA03 CA07 CA15 CA19 CB10 CC10 DA00

Claims (4)

[Claims] 1. A weather-resistant protective material characterized in that a resin layer is provided on at least one surface of a long-fiber nonwoven fabric having a basis weight of 100 g / m ² or more having a three-dimensional entangled structure by needle punching. 2. The weather-resistant protective material according to claim 1, wherein the basis weight of the resin layer is 50 g / m ² or more. 3. The weatherable protective material according to claim 1, wherein the resin layer contains a benzotriazole-based or benzophenone-based ultraviolet absorber. 4. The weatherable protective material according to claim 1, wherein the resin layer contains a hindered amine-based, hindered phenol-based, or phosphorus-based antioxidant.