JP2001349062A - Sheet for construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet for construction, which is light, and highly strong and has flame retardancy and is excellent in antifouling property. SOLUTION: This sheet for construction comprises a polyolefine layer containing a flame retardant agent and a water repellent agent laid on at least one side of an woven knit cloth sheet made from polyolefine drawn filament yarn containing the flame retardant agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a construction sheet.

[0002]

2. Description of the Related Art Construction sheets are temporarily installed on a construction site such as a building or a house in order to prevent bolts and other construction materials from falling from the construction site and to secure safety for passersby. Applications such as mounting on the outer surface of a structure, or covering building materials or construction equipment to prevent damage to the building materials from exposure to wind or rain, or to shield them from welding sparks, etc. It is a sheet used for.

Conventionally, as a construction sheet, a so-called PVC sheet in which a polyvinyl chloride layer is laminated on a woven or knitted fabric using a filament yarn such as polyester or nylon is generally used. The advantages are that the woven and knitted fabric has sufficient strength, is flexible, and is provided with flame retardancy by a polyvinyl chloride layer. There is a problem that toxic gas is sometimes generated, there is a problem that it is difficult to handle in a spreading work at a high place due to its heavy weight, and there is a problem that the plasticizer bleeds easily due to bleeding.

In order to solve such a problem, in recent years,
Attempts have been made to construct construction sheets in which a polyolefin layer is laminated on a woven or knitted fabric made of polyolefin filaments, which is lightweight, has excellent filament formability, and does not generate toxic gas. Since these are usually flammable, there is a danger that they will spread due to welding sparks or the like. Therefore, JISA8
952 "Sheet for construction work" has a flameproof standard, which is generally subjected to various flame retarding treatments so as to pass the standard.

[0005] In the temporary industry, construction sheets are usually leased and used in a lease form.
Use a washing machine after the work is completed because it is soiled by cement, paint, machine oil, iron rust, earth and sand, atmospheric pollutants, etc. that are scattered on the work site while being stretched on the work site and used for a long time. Has been cleaned and reused at the next construction site. However, the construction sheet is wrinkled due to cleaning and the appearance is impaired,
Since there is a problem that the dimensions change due to shrinkage and the dimensions do not match at the time of stretching, there has been a demand for a construction sheet having excellent antifouling properties that does not require cleaning.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a construction sheet having a light weight, high strength, flame retardancy, and excellent antifouling property. With the goal.

[0007]

In order to achieve the above object, a construction sheet of the present invention contains a flame retardant and a water repellent on at least one surface of a woven or knitted fabric made of a polyolefin drawn yarn containing a flame retardant. Of polyolefin layers to be laminated.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
As the polyolefin used in the drawn polyolefin yarn of the present invention, those having a drawing effect and high strength are preferable, and specific examples include high-density polyethylene, linear low-density polyethylene, and polypropylene.

As the form of the above drawn yarn, monofilaments formed by extrusion from a die and subjected to uniaxial drawing, multifilaments obtained by bundling a plurality of monofilaments having a low fineness, and flat films obtained by subjecting a formed film to slitting and then uniaxially drawing. Any of yarns, split yarns obtained by subjecting flat yarns to splitting treatment, and the like can be used.

The method for producing the drawn yarn is not particularly limited, and a drawn yarn that has been subjected to uniaxial drawing by a known production method is formed. It is important that the stretching ratio is 4 to 12 times, more preferably 6 to 10 times. If the stretching ratio is less than 4 times, the tensile strength becomes insufficient and it becomes difficult to achieve the object of the present invention. If the stretching ratio exceeds 12 times, productivity is lowered due to breakage in stretching and the like, which is not preferable. The stretching treatment is performed at a temperature lower than the melting point of the polyolefin and higher than the softening point. As a heating method, any method such as a hot roll method, a hot plate method, an infrared method, and a hot air method can be adopted. The formula is preferred in terms of stretching efficiency, high-speed productivity, and stability. The formed undrawn yarn is heated and drawn by the peripheral speed difference between the front and rear rolls.

The tensile strength of the drawn yarn obtained by the above drawing treatment is 3 cN / dt or more (centinewton per decitex).
And more preferably 4 cN / dt or more.
If the tensile strength is less than 3 cN / dt, the strength of the sheet for construction is insufficient, which is not preferable. The fineness of the drawn yarn is 100
~ 3,000 decitex (hereinafter abbreviated as dt) is preferable, and 300 to 1000 dt is more preferable. Fineness is 100
If it is less than dt, the strength of the sheet for construction will be insufficient and 3
If it exceeds 000 dt, the flexibility is inferior and the handleability deteriorates, which is not preferable.

Various weaves such as plain weave, twill weave, entangled weave and mosaic weave can be used as the weave of the woven or knitted fabric.
As the knitting structure, warp knitting, weft knitting and the like are appropriately used. The driving density of the warp and the weft is preferably 5 to 30 yarns / 2.54 cm, more preferably 10 to 20 yarns / 2.54 cm.
Also, the basis weight of textile fabric is preferably ^{100~500g / m 2, 200~400g / m} 2 is more preferable.

A work sheet is formed by providing a polyolefin layer containing a flame retardant and a water repellent on at least one surface of the woven or knitted fabric. As a method for providing the polyolefin layer, an extrusion lamination method, a dry lamination method, or the like can be adopted, but the extrusion lamination method is preferable. As the polyolefin used for the polyolefin layer, low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-alkyl acrylate copolymer, polypropylene, propylene-ethylene copolymer, etc. are usually laminated. Can be used, but the same type as the polyolefin drawn yarn.
Similar resins are preferred in terms of adhesiveness. In addition, the thickness of the polyolefin layer can be arbitrary,
0 μm is preferred, and 50-100 μm is more preferred.

As the flame retardant used in the present invention, known flame retardants such as halogen-based, phosphorus-based, and inorganic-based flame retardants are used. Flame retardants are preferred, and brominated flame retardants are most preferred. Specifically as a brominated flame retardant,
Aromatic brominated flame retardants such as tetrabromobisphenol A, decabromodiphenyl ether, octabromodiphenyl ether, bisdibromopropyl ether tetrabromobisphenol S, and alicyclic brominated compounds such as hexabromocyclododecane and dibromoethyldibromocyclohexane Flame retardants, liquid bromine-based flame retardants such as pentabromodiphenyl ether and tetrabromodiphenyl ether,
And phthalimide-based flame retardants such as ethylenebistetrabromophthalimide. These may be used alone or as a mixture of two or more. Of these, phthalimide-based flame retardants have excellent heat resistance as a flame retardant used in the polyolefin layer, so that it is possible to raise the melting temperature in the extrusion lamination method, so that the woven fabric and the polyolefin layer are separated. The strength can be improved, and the phthalimide-based flame retardant does not cause bleeding. Therefore, it is preferable because there is no inconvenience such as insufficient heat welding due to the bleeded flame retardant during the heat welding process.

It is preferable to use a flame retardant auxiliary in combination with the bromine flame retardant in view of improving the flame retardant effect. Specific examples of the flame retardant aid include antimony trioxide, antimony trichloride, and zinc oxide. The compounding ratio of bromine-based flame retardant / antimony-based flame retardant aid is 2/1 to 3 /
1 is preferred.

The amounts of the bromine-based flame retardant and the antimony-based flame retardant auxiliary (hereinafter collectively referred to as flame-retardant) are as follows. % By weight is preferred.
-10% by weight is more preferred. If the amount of the flame retardant is less than 3% by weight, the flame retardant effect is not sufficient, and the flame retardant is 12% by weight.
Exceeding the mechanical strength of the drawn polyolefin yarn is unfavorable because the mechanical strength of the drawn polyolefin layer is reduced, and the polyolefin layer has problems such as insufficient heat welding during post-processing such as edge processing due to bleeding.

As the water repellent used in the present invention, a known water repellent such as a silicone water repellant or a fluorine water repellent is used, and a silicone water repellant is preferable.

Specific examples of the silicone water repellent include silicone compounds such as polydimethylsiloxane, polydiphenylsiloxane, and polytetramethylsilmethylenesiloxane, or modified compounds obtained by introducing a hydroxyl group, amino group, epoxy group, or the like into these compounds. And the like.

Specific examples of the fluorine compound include trifluoroethylene, tetrafluoroethylene, chlorotrifluoroethylene, polytrifluoroethyl acrylate, and polypentadecafluorooctyl acrylate.

The compounding amount of the water repellent is 0.1 to 10
% By weight, more preferably 0.5 to 5% by weight.
If the content of the water repellent is less than 0.1% by weight, the antifouling property is insufficient, and if it exceeds 10% by weight, the adhesion of the polyolefin layer to the woven or knitted fabric is undesirably reduced.

As a method of blending the above flame retardant and water repellent, the flame retardant and water repellent may be mixed with a polyolefin and supplied directly to an extruder, or a high concentration flame retardant may be previously contained in the base resin. A masterbatch containing a water repellent and a water repellent may be manufactured and supplied as the masterbatch.

The polyolefin used in the present invention includes:
Within the scope of the present invention, an antioxidant,
Ordinary additives such as an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, a pigment, an inorganic filler, a nucleating agent, a foaming agent, and a dispersant may be added.

[0023]

As described above, the construction sheet according to the present invention has a polyolefin layer containing a flame retardant and a water repellent provided on at least one surface of a woven or knitted fabric made of a polyolefin drawn yarn containing a flame retardant. The sheet is lightweight, high-strength, flame-retardant, and has excellent antifouling properties.

[0024]

EXAMPLES High density polyethylene (MFR = 0.7 g / 1)
0 min, density = 0.960 g / cm³)
Tylene bistetrabromophthalimide and antimony trioxide
Containing 70% by weight of flame retardant mixed with 3: 1
Composition containing 10% by weight as a master batch
Film formed by inflation method using material
After slitting, the film is stretched at a draw ratio of 6.8 times, and the fineness is 700d.
You got t flat yarn. This flat yarn
15 × 14 / 2.54cm by plain weaving machine
A woven fabric was formed. Next, as a laminate layer, low density
Polyethylene (MFR = 8.0 g / 10 min, density =
0.917 g / cm³), The flame-retardant material-containing mass
5% by weight of terbatch and polydimethylsiloxane as a water repellent
5% by weight master batch containing 40% by weight roxane
By extrusion lamination using a resin composition containing
Polyolefin layers with a thickness of 50 μm each on both sides of the woven fabric
Weight per unit weight 190g / m ²Form the construction sheet
Was. The maximum tensile load of the above construction sheet is 12
8kgf / 3cm, 122kgf / 3cm in horizontal direction, maximum
The elongation was 24.6% in the machine direction and 34.5% in the transverse direction.
This value is based on JISL1091 for building construction sheet 2
It passes the case. Also, according to JIS A8952
In the flame retardancy test, the number of times of flame contact was 4 and passed the flameproof standard.
ing. Furthermore, the above construction sheet has excellent antifouling properties,
After collecting from the construction site, a simple dust removal
It was possible to reuse it without the need for cleaning.

Claims (1)

[Claims] 1. A construction sheet obtained by laminating a polyolefin layer containing a flame retardant and a water repellent on at least one surface of a woven or knitted fabric made of a drawn polyolefin yarn containing a flame retardant.