JPH0849998A - Impact resisting sheet comprising high strength uniaxially oriented body and its production - Google Patents

Abstract

PURPOSE:To obtain a thin and light, highly elastic impact-resisting sheet with a high strength by laminating uniaxially oriented bodies each comprising an ultra-high- molecular weight polyolefin with a specified limiting viscosity in such a manner that the axis of the orientation is different between each other while being made up of a sheet material solidified with a matrix. CONSTITUTION:A uniaxially oriented body made of ultra-high molecular weight polyolefin is a parallely arranged body which comprises a mesh-shaped web body yet to be expanded in width having a crack or slit and matrixes 3 and 4 are laminated on both surfaces of a laminate body 2 made up of uniaxially oriented bodies laminated with the axis of the orientation differentiated therebetween. In this case, to improve adhesiveness thereof, it is desired to make the surface of the crossed laminate body 2 of the uniaxially oriented body undergo a surface treatment by a corona discharging or the like and an embossing treatment of a satin or the like. The superhigh molecular polyolefin herein used has a limiting viscosity of 5dl/g or more (in 135 deg.C decalin solution) and a viscosity average molecular weight equivalent to 500,000-12,000,000). This enables the obtaining of a thin and light impact resisting sheet with a high strength and a high elastic modulus.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in bulletproof vests, armor plates of armored vehicles, shields of police riot police, etc., and is thin, inexpensive, lightweight, has high strength, high elastic modulus, and is superior in performance. The present invention relates to an impact sheet.

[0002]

2. Description of the Related Art Conventionally, as an impact resistant sheet used for a bulletproof vest, a sheet obtained by hardening a woven fabric such as aramid fiber with a rubber matrix has been proposed. But,
A sheet using these woven fabrics has a problem that it requires a lot of fibers to be aligned, which is troublesome. In addition, it is difficult to make a thin sheet, and it has drawbacks such as poor comfort as a bulletproof vest. Furthermore,
The armor plates of armored vehicles and the shields of police riot police are made of metal, but they are heavy and have problems in terms of handling.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made as a result of intensive studies for solving the above-mentioned problems, and provides a uniaxially oriented body composed of an ultrahigh molecular weight polyolefin superoriented tape or a reticulated web thereof. The present invention provides an impact resistant sheet which is thin, light and has high strength and high elastic modulus due to its flatness.

[0004]

Means for Solving the Problems That is, the present invention provides an unwidened body of a reticulated web in which a uniaxially oriented body made of an ultrahigh molecular weight polyolefin having an intrinsic viscosity of 5 dl / g or more (measured with a decalin solution at 135 ° C.) has cracks. And a uniaxially oriented body, wherein the uniaxially oriented body is laminated so that the orientation axes are different from each other, and is made of a sheet material hardened in a matrix. The matrix is a thermoplastic resin, a curable resin,
The impact-resistant sheet is at least one selected from the group consisting of rubber elastic materials, and the third invention is
A) Intrinsic viscosity (measured with decalin solution at 135 ° C) 5 dl /
g) manufacturing process of orienting material for ultra high molecular weight polyolefin, B) uniaxially orienting the orienting material, C) cracking or slitting the orienting material before or after uniaxial orientation, D) uniaxial orientation A fourth aspect of the present invention is a method for producing an impact resistant sheet, which comprises a step of laminating a plurality of layers of a body so that the orientation axes are different, and E) a step of solidifying a laminated body with a matrix to form a sheet. Measured with a decalin solution at 135 ° C.) Process for producing a material for orienting ultra-high molecular weight polyolefin of 5 dl / g or more, B) Step for uniaxially orienting the material for orienting, E ′) Step for solidifying a uniaxially oriented body with a matrix to form a sheet , D ') a step of laminating and integrating a plurality of layers of sheet materials so that the orientation axes are different, and C') a method of producing an impact resistant sheet, comprising the step of cracking the uniaxially oriented body in the sheet material, A fifth aspect of the invention is A) a process for producing a material for orienting an ultrahigh molecular weight polyolefin having an intrinsic viscosity (measured with a decalin solution at 135 ° C.) of 5 dl / g or more, B) a step for uniaxially orienting the material for orientation, B ′). A step of orienting the orienting material horizontally and uniaxially, C ") a step of cracking or slitting in the orientation direction before or after orienting the longitudinally and laterally uniaxially oriented body, D") orienting the longitudinally and laterally uniaxially oriented body Laminating process with different axes, E ″)
A sixth aspect of the present invention is a method for producing an impact resistant sheet, which comprises a step of solidifying a laminated body with a matrix to form a sheet, and the sixth invention is a step of uniaxially orienting the orientation material of B), and bonding the surface with affinity for the matrix The method for producing the impact resistant sheet according to any one of 4 and 5 above, wherein the uniaxially oriented body has a draw ratio of 3 times or more, and the seventh invention is the method according to any one of 3 to 5 above. An eighth aspect of the present invention is the method of producing an impact resistant sheet according to any one of 3 to 7, wherein the method of forming cracks in the uniaxially oriented body is a split method. The invention of 9 is, as a longitudinal uniaxial orientation method, in which a reticulated film having a wide film with intermittent slits in the longitudinal direction is oriented in the longitudinal direction in a free space of 3 times or more of the film width before orientation. Of the impact resistant sheet according to any one of 8 A tenth aspect of the invention is a lateral uniaxial orientation method, in which a reticulated film in which a wide film is provided with intermittent slits in the lateral direction is folded in the longitudinal direction and gripped in the state of wrinkles to orient in the lateral direction. The method for producing an impact resistant sheet according to any one of 3 to 8 above.

Hereinafter, the impact resistant sheet of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention. In FIG. 1, the uniaxially oriented body of the ultra-high molecular weight polyolefin is a juxtaposed body made of unwidened webs having cracks or slits, and both sides of the laminated body 2 in which the uniaxially oriented body is laminated with different orientation axes. This is an impact resistant sheet 1 in which the matrices 3 and 4 are laminated. In the impact-resistant sheet 1, the uniaxially oriented crossed laminate 2 is used.
In order to improve the adhesiveness of the surfaces of the matrixes 3 and 4, the surface of the uniaxially oriented crossed laminate 2 is subjected to surface treatment such as corona discharge, flame treatment, plasma treatment, ozone treatment, chemical treatment, satin finish, unevenness, etc. It is preferable to carry out the embossing treatment.

The ultrahigh molecular weight polyolefin of the present invention is
Intrinsic viscosity (in decalin solution at 135 ° C) 5dl / g or more,
Intrinsic viscosity in the range of 5-50 dl / g, preferably 8-40
dl / g, more preferably 10 to 30 dl / g, having a viscosity average molecular weight of 500,000 to 12,000,000, preferably 900,000 to 9,000,000, and more preferably 1,200,000 to 600.
It is equivalent to ten thousand.

When the intrinsic viscosity is less than 5 dl / g, the mechanical properties of the oriented product deteriorate, and when it exceeds 50 dl / g, the workability is deteriorated, which is not preferable.

The shape of the above ultrahigh molecular weight polyolefin is not particularly limited, but in order to obtain a homogeneous film in the post-processing, a granular or powdery one is usually preferably used. Their particle size is 2000 μm or less, preferably 1
˜2000 μm, more preferably 10 to 1000 μm. Further, it is preferable that the particle size distribution is narrow, because there are few defects when compression-molding to form a sheet.

The ultra-high molecular weight polyolefin of the present invention comprises at least one compound selected from compounds containing transition metals of Groups IV to VI of the periodic table such as titanium compounds, vanadium compounds, chromium compounds, zirconium compounds and hafnium compounds. It is produced by homopolymerizing or copolymerizing an α-olefin in the presence of a catalyst formed by combining the contained catalyst component and, if necessary, an organometallic compound.

The α-olefin has 2 to 1 carbon atoms.
2, preferably 2 to 8 are preferably used. Specific examples include ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene and 1-dodecene.

Of these, ethylene, propylene, 1-butene, 4-methyl-1-pentene and 1-hexene are particularly preferable. Further, as other comonomers, dienes such as butadiene, 1,4-hexadiene, vinyl norbornene, and ethylidene-norbornene may be further used in combination.

The comonomer content of the α-olefin copolymer is 0.001 to 10 mol%, preferably 0.0
It is used in the range of 1 to 5 mol%, more preferably 0.1 to 1 mol%.

The uniaxially oriented body of the ultrahigh molecular weight polyolefin of the present invention means an unwidened body (FIG. 3) of a reticulated web (FIG. 2) in which cracks are formed in the uniaxially oriented film of the ultrahigh molecular weight polyolefin with a hot blade or a splitter. Is included. Incidentally, although FIG. 3 is shown in a slightly widened state for easy understanding, in reality, there is almost no gap.

The matrix of the present invention includes a thermoplastic resin, a curable resin and / or a rubber elastic body,
Specifically, polyethylene, polyolefin resin such as polypropylene, polyester resin, polyamide resin, polycarbonate resin, polyphenylene oxide resin,
Thermoplastic resin such as ABS resin, phenolic resin, urea resin, melamine resin, epoxy resin, polyurethane resin, unsaturated polyester, diallyl phthalate resin, curable resin such as silicon resin, polyvinyl chloride, chlorinated polyethylene, ethylene- Examples thereof include rubber elastic bodies such as propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, and styrene-butadiene copolymer rubber.

The method for producing the impact resistant sheet of the ultrahigh molecular weight polyolefin of the present invention will be described in detail below.

The production method 1 of the present invention comprises A) an intrinsic viscosity (135
℃ measured in decalin solution) 5 dl / g or more of the process for producing a material for orienting ultra-high molecular weight polyolefin, B) a step of uniaxially orienting the material for orientation, C) a crack before or after uniaxially orienting the material for orientation, or The process of splitting,
It is a method for producing an impact resistant sheet including a step of D) laminating a plurality of layers of unwidened slits of a uniaxially oriented body so that orientation axes are different, and E) a step of hardening the laminated body with a matrix to form a sheet.

The production method 2 of the present invention comprises A) an intrinsic viscosity (135
° C measured in decalin solution) 5 dl / g or more ultra high molecular weight polyolefin orienting material manufacturing step, B) orienting the orienting material uniaxially, E ') a step of solidifying the uniaxially oriented body with a matrix to form a sheet, It is a method for producing an impact resistant sheet, which includes a step of D ') laminating and integrating a plurality of layers of a sheet material so that orientation axes are different, and a step of C') forming a slit in a uniaxially oriented body in the sheet material.

The production method 3 of the present invention comprises A) an intrinsic viscosity (135
℃ measured in decalin solution) 5 dl / g or more production process of ultra-high molecular weight polyolefin orientation material, B) orientation material oriented uniaxially, B ') orientation material oriented horizontally uniaxially, C ″ ) Slitting or splitting the longitudinal and transverse uniaxially oriented bodies before or after uniaxial orientation, D ") Laminating the longitudinal and transverse uniaxially oriented bodies with different orientation axes, E") Laminating a matrix It is a method of producing an impact resistant sheet including a step of solidifying into a sheet.

The process for producing a material for orienting an ultra-high molecular weight polyolefin having an intrinsic viscosity of A) of the present invention (measured with a decalin solution at 135 ° C.) of 5 dl / g or more is the method of melting after being melted by an extruder or the T-die. Method of film formation by the method,
Further, a method of dissolving into a film after dissolving with a solvent, a method of skive method or the like or a method of compression-molding a film of ultra-high molecular weight polyolefin in a solid phase state, then rolling to form a sheet and orienting the same can be mentioned. The compression method may be a batch method, a continuous method, or the like. The batch type includes slide type, rotary type and the like, and the continuous type compression method includes, for example, sandwiching the powder of ultra-high molecular weight polyolefin between a pair of vertically facing endless belts and compressing while moving the endless belts. It is an orienting material obtained by a molding method or the like.

In the uniaxial stretching step of the B) orienting material of the present invention, the material is uniaxially oriented by a stretching method and / or a rolling method and the like, and is not particularly limited. Cylinder stretching, roll stretching, hot plate stretching and the like can be mentioned. Since stretching of the ultra high molecular weight polyolefin material is slippery,
It is desirable to apply stretching tension between clover rolls, multi-stage rolls, Nelson rolls, and the like.

The method of uniaxially orienting the orienting materials of the production method B) and the production method B ") of the present invention is basically a common method and is not particularly limited.
As the longitudinal uniaxial stretching method (Fig. 4a), a mesh film (Fig. 4b) in which a wide film is provided with intermittent slits in the longitudinal direction as shown in Fig. 4 is prepared by stretching the film width three times the film width before orientation. It is desirable to provide a stretching zone having the above free space for stretching.

As the B ") transverse uniaxial stretching method, as shown in FIGS. 5 (a) and 5 (b), a tenter method, a pulley method, or the like is used. Reticulated film with intermittent cracks,
It is desirable to grip with the folding folds in the longitudinal direction and orient in the lateral direction.

The above-mentioned orientation temperature is in the range below the melting point of the oriented material, usually 20 to 160 ° C., preferably 60 to 150.
C., more preferably 90 to 145.degree. It is preferable that the stretching step is performed not only in one stage but also in multiple stages. In this case, it is desirable to raise the temperature sequentially to perform the alignment.

The stretching speed can be appropriately selected depending on the orientation method, the molecular weight of the polymer, the composition ratio, etc., but is usually in the range of 1 mm to 500 m / min in the longitudinal and transverse stretching methods. More specifically, in the case of batchwise orientation, 1 to 50
The range is 0 mm / min, preferably 1 to 100 mm / min, and more preferably 5 to 50 mm / min. On the other hand, in the case of continuous orientation, it is usually 0.1 to 500 m / min, preferably 1 to 200 m / min, more preferably 10 to 200 m.
Within the range of / minute. It should be noted that the high speed setting is more preferable in consideration of economy.

As for the draw ratio, the higher the draw ratio, the higher the strength of the oriented product obtained. Therefore, it is desirable to increase the draw ratio as much as possible. In order to stretch at a high ratio, it is desirable to orient in a solid state, and examples of these methods include a method of using rolling and tensile stretching in combination, a gel stretching method, and the like.

In the present invention, the total draw ratio, which is the total draw ratio of rolling and orientation, is 20 times or more, preferably 30 times or more, more preferably 50 times or more, and further preferably 60 to 200 times. desirable.

The tensile strength of the uniaxially oriented body after the above orientation is 1
2 g / denier or more, preferably 50 g / denier or more, more preferably 100 g / denier or more,
The tensile modulus is 200 g / denier or more, preferably 500 g / denier or more, more preferably 1000.
g / denier or more, more preferably 1500 g / denier or more.

The reticulated web of the present invention does not exhibit sufficient strength when measured as it is, depending on the method of slitting or splitting, but the constituent filament itself has sufficient strength. Therefore, the tensile strength of the web forming the reticulated web must be 12 g / denier or more when measured by twisting. The strength after twisting depends on the number of twists, and the displayed strength is indicated by the optimum number of twists. The optimum twist number varies depending on the denier used for measurement, and generally, the optimum twist number for a 1000 denier filament is around 100 turns / m.

The steps of C) and C ″) of the present invention for cracking before or after uniaxial orientation are basically the same as in the above production methods 1 and 3, and the ultra high molecular weight polyolefin film or Mechanical methods such as beating method of uniaxially oriented film, twisting method, sliding rubbing method, brushing method, air jet method,
It is a process of forming innumerable minute cracks or cuts by any one method such as an ultrasonic method and a laser method.

Among these, the rotary mechanical method is particularly preferable. Examples of such a rotary mechanical method include various types of splitters such as a tap screw splitter, a file-like rough surface splitter, and a needle roll splitter. For example, the tap screw type splitter shown in FIG. 6 is usually a pentagonal or hexagonal prism having 10 to 40, preferably 15 to 35, threads per inch. Further, as the file-like rough surface body splitter shown in FIG.
Those disclosed in Japanese Patent No. 0 are preferable. The file-like rough surface splitter is a round file for ironwork or a rough surface similar to this with the surface of the circular cross-section axis being formed by cutting two spiral grooves at equal pitches on the surface.

The method for producing the reticulated web of the present invention is not particularly limited, but as a typical example, as shown in FIG. 8, a splitter 7 is arranged between the nip rolls 5 and 5'and the nip rolls 6 and 6 ', and stretched. The working material 20 is moved along the splitter 7 while applying tension, and is brought into sliding contact with a splitter rotating at a high speed to split (split) and reticulate.

As shown in FIG. 7, the splitter 7 has a surface 9 of a circular cross-section shaft 8 of the splitter 7 formed into a roughened surface having a file-like shape, and two spiral grooves 10 and 10 'are cut at equal pitches. The grooves 10 and 10 'are formed as square grooves having a depth equal to or higher than the height of the blade on the surface. 9 and 1
Reference numeral 0 denotes a part of the AA ′ cross section and the axial cross section when the drawing material 20 is split into pieces by bending the drawing material 20 on the splitter of FIG. 5, and the drawing material 20 is a splitter due to its tension. The drawing material 20 that fits in the spiral grooves 10 and 10 'of the above and contacts the perforation of the surface 9 receives a large pressing force due to the concentration of the tension, and also receives the force of being pulled in the width direction to split the fibers. Is reticulated.

The moving speed of the film is usually 1 to 1000.
m / min, preferably 10 to 500 m / min. Also,
The rotational speed (peripheral speed) of the splitter can be appropriately selected depending on the physical properties of the film, the moving speed, and the properties of the target reticulated film, but is usually 10 to 3000.
m / min, preferably 50 to 1000 m / min. The contact angle between the film and the splitter is 30 to 180.
It is desirable that the angle is 40 to 160 degrees.
In addition, since the film is slippery, it may be difficult to hold the film at a predetermined speed in the nip rolls installed before and after the splitter.Therefore, a nip roll and a clover roll may be used together, or a Nelson roll may be used. It is desirable to take anti-slip measures such as combining these.

In the method of brushing or the method of using a rotary splitter, the operation is preferably carried out by applying tension to the oriented material. The tension is preferably such that the film is deformed by 0.1 to 3%, preferably 0.5 to 2% as elongation. Further, a controller such as a dancer roll may be installed to keep the tension of the film constant during the split.

The temperature during splitting is usually -20 to +1.
00 ° C., preferably −5 to + 50 ° C., more preferably 0 to 20 ° C. is desirable, and the splitting process may be performed not only in one step but also in multiple steps, and for a material having a large thickness. Alternatively, split processing may be performed from the front and back.

It is also possible to press the film with a rotary baking blade heated above the melting point of the resin to form slits in a zigzag pattern or the like to form a net. Furthermore, it is also possible to employ a method in which a rotary body having a large number of razor blades embedded therein is used to make a slit with the sharp edge of the razor blade.

As another method for cracking in C ') of the production method 2 of the present invention, a uniaxially oriented body alone or a laminated body which is cross-laminated in advance is solidified with a matrix to form a sheet, and this sheet is as shown in FIG. It is also possible to form cracks inside by bending, rubbing, impacting or the like with the lateral groove roll 11 or the like.

The D) step of laminating the uniaxially oriented body so that the orientation axes of the uniaxially oriented body are different from each other is most preferably latitudinal and weft lamination of a plurality of layers of the uniaxially oriented body, but the crossing axis is not necessarily 90.
The angle need not be an angle of 60 °, and is appropriately selected such as 60 ° or 30 °.

Further, as in the production method 2 of the present invention, a uniaxially oriented body previously hardened with a matrix may be laminated and integrated so that the orientation axes of the uniaxially oriented body intersect.

Further, as in the production method 3 of the present invention, the longitudinal uniaxially stretched body and the lateral uniaxially stretched body may be continuously introduced to intersect the orientation axes to be integrated with the matrix.

In the step of solidifying a uniaxially oriented body of E), E ′), and E ″) of the present invention with a matrix to form a sheet, the sheet is sandwiched between matrix sheets of resin, rubber elastic body or the like and passed between rolls for pressure bonding. There are no particular limitations on the method of integration, the method of impregnating a laminate with a curable resin for integration, or the method of dipping to laminate integration.
The stretched web of the present invention can also be produced by the method of JP-A-3-130116 by a super-stretched reticulated web having an adhesive layer on the surface, and the adhesive layer in that case is a layer having an affinity for the matrix. Is desirable. Specifically, it is a case where an unsaturated polyester or epoxy resin is used as a matrix in a super-stretched reticulated web having a layer in which a powder of unsaturated polyester or epoxy resin is mixed. When the matrix is rubber, an adhesive layer such as a polyolefin elastomer having an affinity for rubber is used.

In this case, as the strength and elastic modulus of the super-stretched web, numerical values calculated by excluding the thickness of the adhesive layer are used.

It is particularly desirable that the ultrastretched reticulated web of the present invention is a wide web. With a wide width, not only a large molded product can be molded in a short time, but also widening at the time of lamination is easy, and since there are few laminated lap portions, a uniform product can be obtained.

[0045]

The impact-resistant sheet of the present invention uses the flatness of the material by using the unwidened body of the reticulated web in which cracks of ultra-high molecular weight polyolefin are formed, and is therefore thin, light, and high in strength. An impact resistant sheet having a high elastic modulus can be obtained. Also, because it uses a wide reticulated web,
It has the same effect as the case where a large number of fibers are processed together.

[0046]

EXAMPLES The present invention will be described in more detail below with reference to examples. Film production: (compression roll forming machine) 1. Roll: Diameter 500mmφ Face length 300mm 2. Steel belt: wall thickness 0.6mm width 200mm 3. Small diameter roller: Diameter 12mmφ Face length 250mm 4. Pressure plate: length 1000 mm width 200 mm 5. Hydraulic cylinder: Diameter 125 mmφ Using the above device, 1 ultra high molecular weight polyethylene powder having an intrinsic viscosity of 14 dl / g (viscosity average molecular weight of about 2,000,000) was used.
Heated to 30 ℃, the average pressure on the material is about 6kg / c
A sheet having a thickness of 1.1 mm and a width of 100 mm was continuously compression-molded at a speed of 1 mm / min by pressurizing at m ³ . Next, this sheet is supplied between a pair of rolls having a diameter of 150 mm, a face length of 300 mm, and a roll distance of 30 μm which rotate in the opposite direction at the same peripheral speed of 1 m / min whose surface temperature is adjusted to 140 ° C. A film having a draw ratio of 7 times was obtained. Production of stretched film: (Stretching device) 1. Heater: 3 metal rolls for preheating, diameter 250 mmφ, surface length 200 mm Metallic roll for drawing 1 diameter 125 mmφ, surface length 200 mm Oil for heat medium is circulated inside the roll.

2. Cooling metal rolls: 3 rolls, diameter 250 mm, surface length 200 mm Water circulates inside the rolls.

3. Nip roll entrance side: 200 mmφ silicon rubber roll nips between two preheating metal rolls.

Outlet side: 200 mmφ silicon rubber roll is nipped between two cooling metal rolls.

The rolled sheet was stretch-stretched using the stretching device. The tensile stretching was repeated 3 times under the following conditions. The obtained tape had a width of 32 mm and a thickness of 60 μm, and the total draw ratio of rolling and drawing was 105 times.

Number of times of stretching Metal roll temperature (° C.) Nip roll peripheral speed (m / min) Stretching ratio For preheating Stretching Inlet side Outlet side (times) 1 135 140 1 4 4 2 140 145 4 10 2.5 2.5 3 140 150 150 15 1.5 Total 15 times Manufacture of reticulated web: The stretched tape was split by a splitter under tension with a speed difference of 1.2% between nip rolls by the split method shown in FIG. 5 to prepare a reticulated web. . The conditions are as follows.

Film speed: Inlet-side roll 20 m / min Outlet-side roll 20.24 m / min Splitter: Hexagonal bar edge provided with 32 thread / inch tap screw-like protrusions (maximum diameter 25 mmφ) Contact angle: 90 Degree Rotational speed: 800 rpm (Surface speed 62.8 m / min) Sliding ratio: 3.14 (Splitter rotation speed / Film speed) The reticulated web was prepared and wound into a roll. The physical properties of this reticulated web are shown below.

Tensile Strength (g / d) Tensile Elastic Modulus (g / d) 23 1150 Example 1 An ethylene-propylene-diene copolymer rubber was coated on both sides using the unexpanded body of the reticulated web produced above. An impact resistant sheet was prepared by laminating the sheets, and the evaluation results are shown below.

Roll surface length 300 mm φ Sheet width 200 mm Rolled width 200 mm Stretching ratio 85 times Total stretched width 62 mm Tensile strength 22 g / d Tensile modulus 1050 g / d

[0055]

Since the impact resistant sheet of the present invention is formed from a uniaxially stretched body composed of an unwidened body of a cracked reticulated web of an ultra high molecular weight polyolefin, it is thin, cheap, lightweight and high in strength. It has strength and high elastic modulus, and has excellent performance such as impact resistance. In addition, since a wide reticulated web is used instead of individual fibers, it has the same strength as a large number of fibers collectively processed. Therefore, it has high productivity and can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view of an impact resistant sheet of the present invention.

FIG. 2 is a conceptual diagram of a reticulated web made of ultra-high molecular weight polyolefin.

FIG. 3 is a conceptual diagram of an unwidened body of the reticulated web.

FIG. 4 is a schematic diagram of a stretching method using a stretching device having a stretching region of 3 times or more.

FIG. 5 (a) Schematic diagram of a transverse stretching apparatus for ultra-high molecular weight polyolefin (b) Schematic diagram of a transverse stretching apparatus for ultra-high molecular weight polyolefin

FIG. 6 is a schematic diagram of a tap screw type splitter.

FIG. 7 is a schematic diagram of a file-like rough surface splitter.

FIG. 8 is a main schematic diagram of the reticulation process.

9] AA 'of the file-like rough surface splitter of FIG.
Cut line cross section

10 is a cross-sectional view of the file-like rough surface splitter of FIG.

FIG. 11: Bending device for cracking a sheet

[Explanation of symbols]

 1 Impact-Resistant Sheet 2 Parallel Body of Reticulated Web 3,4 Sheets 5,5 'Entrance Side Nip Roll 6,6' Exit Side Nip Roll 7 Splitter 8 Shaft 9 Surface 10, 10 'Groove 11 Side Groove Roll 20 Stretching Material

Continued Front Page (72) Inventor Kazuhiko Kurihara 3-11-5-1002 Takashimadaira, Itabashi-ku, Tokyo

Claims (10)

[Claims] 1. A uniaxially oriented body composed of an ultrahigh molecular weight polyolefin having an intrinsic viscosity of 5 dl / g or more (measured with a decalin solution at 135 ° C.) is a parallel body composed of cracked sheets or unwidened bodies of a reticulated web, An impact resistant sheet comprising a sheet material in which uniaxially oriented bodies are laminated so that their orientation axes are different from each other, and are hardened in a matrix. 2. The impact resistant sheet according to claim 1, wherein the matrix is at least one selected from the group consisting of a thermoplastic resin, a curable resin, and a rubber elastic material. 3. A) a process for producing a material for orienting an ultrahigh molecular weight polyolefin having an intrinsic viscosity of 5 dl / g or more (measured with a decalin solution at 135 ° C.), B) a step for uniaxially orienting the material for orienting, and C) the orientation. Cracking or slitting the working material before or after uniaxial orientation, D) laminating a plurality of layers of the uniaxially oriented body with different orientation axes, E) solidifying the laminated body with a matrix to form a sheet A method for producing an impact resistant sheet, which comprises the steps of: 4. An A) intrinsic viscosity (measured with a decalin solution at 135 ° C.) of 5 dl / g or more of a material for orienting an ultra-high molecular weight polyolefin, B) a step of uniaxially orienting the orienting material, E ′) A step of solidifying a uniaxially oriented body into a matrix to form a sheet, D ') a step of laminating and integrating a plurality of layers of the sheet material so that orientation axes are different, C') a crack in the uniaxially oriented body in the sheet material A method for producing an impact resistant sheet, which comprises the steps of: 5. An A) intrinsic viscosity (measured with a decalin solution at 135.degree. C.) of 5 dl / g or more of a material for orienting an ultrahigh molecular weight polyolefin, B) a step of uniaxially orienting the orienting material, B '). Uniaxially orienting the material for orientation, C ″) cracking or slitting in the orientation direction before or after uniaxially orienting the longitudinal and lateral uniaxially oriented bodies, D ″) the uniaxial and longitudinal orientation A process for producing an impact resistant sheet, comprising the steps of: stacking bodies so that the orientation axes are different; E ″) hardening the laminate with a matrix to form a sheet. 6. The impact resistant sheet according to claim 4, wherein in the step of uniaxially orienting the orientation material of B), an adhesive layer having an affinity for the matrix is provided on the surface. Manufacturing method. 7. The method for producing an impact resistant sheet according to claim 3, wherein the uniaxially oriented body has a draw ratio of 3 times or more. 8. A method for making a crack in a uniaxially oriented body,
It is a split method, The manufacturing method of the impact resistant sheet in any one of Claims 3-7. 9. A longitudinal uniaxial orientation method is characterized by orienting a reticulated film in which a wide film is provided with intermittent slits in the longitudinal direction in the longitudinal direction in a free space of 3 times or more the film width before orientation. The method for producing an impact resistant sheet according to any one of claims 3 to 8. 10. A lateral uniaxial orientation method is characterized in that a reticulated film in which a wide film is provided with intermittent slits in the lateral direction is folded in the longitudinal direction and gripped in the state of wrinkles to orient in the lateral direction. A method for producing the impact resistant sheet according to claim 3.