JPS6226902B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an aromatic polyamide fiber laminate sheet that has good heat resistance, improved tear strength, is relatively lightweight, and has good workability. Conventionally, one or both sides of a base fabric made of synthetic fiber threads, such as polyester fiber threads or vinylon fiber threads, are coated with synthetic resin, such as polyvinyl chloride, or synthetic rubber, such as polyurethane. Sheets, such as waterproof sheets, are known. Such synthetic fiber laminated sheets are widely used for truck canopies, tent fabrics, and the like. In this case, a woven fabric made of synthetic fiber filament yarn is generally used as the base fabric. However, if this base fabric becomes thin (lightweight), the tensile strength of the resulting laminated sheet becomes unsatisfactory, and if the texture of the base fabric is made dense to prevent this drawback, the resulting laminated sheet may tear. There were problems such as unsatisfactory strength and the tendency to tear the key. Furthermore, when the base fabric is thick, there are problems in that the weight of the resulting laminated sheet becomes excessively large, making it inconvenient to handle, and its tear strength is not very high. Furthermore, the surface of the thick base fabric has large irregularities, and in order to smooth it, a large amount of synthetic resin or synthetic rubber must be used for coating, which has the disadvantage of increasing manufacturing costs. apart from,
This results in disadvantages in that the weight of the resulting laminated sheet increases and its tear strength decreases. Furthermore, conventional laminated sheets have the disadvantage of insufficient heat resistance. Conventional fire-resistant sheets are manufactured by coating, impregnating, or pasting a fire-resistant material onto a substrate to form a fire-resistant layer. In this case, it is desirable that the base material also has the same fire resistance as the fire resistant layer. For this reason, if a non-combustible inorganic material such as asbestos or asbestos is used as a base material, the resulting product will be excessively heavy and workability will be poor; if glass fiber is used, for example, the bending resistance will be poor. The durability of the resulting product will be unsatisfactory due to significant defects. Therefore, attempts have been made to use base materials made of flame-retardant fibers such as cotton, nylon, polyester, and vinylon, but a satisfactory product has not yet been obtained. As a heat-resistant organic fiber,
Meta (m) bonded aromatic polyamide fiber (Conex
(trademark), Nomex (trademark)), etc. are known.
The heat resistance of this fiber is sufficient for practical use and there is no risk of it melting during use or processing, and its bending resistance is
It was significantly better than glass fiber and the like. However, the above-mentioned aromatic polyamide fiber has a relatively low tensile strength of 3 to 6 g/d, and its strength is unreliable for use as a laminated sheet for dangerous work, and it is prone to ripping keys during work. The disadvantage is that it is easy to occur. It is generally known that the resistance of a laminated sheet to tearing corresponds approximately to its tear strength. Therefore, in order to increase the tear resistance of the laminated sheet, it is necessary to improve its tear strength. In order to improve the above-mentioned tear strength, the present inventors have already proposed a laminated sheet based on a fabric made of aromatic polyamide fiber threads and different types of fiber threads. However, the heat resistance of the different fiber yarns is inferior to that of the aromatic polyamide fiber yarns, so the heat resistance of the resulting laminated sheet depends on the low heat resistance of the different fiber yarns. For this reason, in the case of laminated sheets containing different types of fiber threads, there has been a problem in that the processing conditions and selection of processing materials are restricted by the low heat resistance of the different types of fiber threads. The object of the present invention is to have not only excellent tear strength but also excellent heat resistance, maintain a good balance between tensile strength and elongation, be relatively lightweight, have high abrasion resistance, and be easy to use. An object of the present invention is to provide an aromatic polyamide fiber laminate sheet with good properties. The above objects are achieved by the present invention. The aromatic polyamide fiber laminate sheet of the present invention has an aromatic polyamide fiber yarn () having a mixing ratio of 60 to 95% by weight, and having a tensile strength of 10 g/d or less and a breaking elongation of 10% or more. and the mixing ratio is 5~
40% by weight of aromatic polyamide fiber yarn () having a tensile strength of 15 to 40 g/d and a breaking elongation of 1 to 8%; It is formed on at least one side of the cloth and includes a covering layer made of synthetic resin or synthetic rubber. In the laminated sheet of the present invention, the high-strength aromatic polyamide fiber yarn () mixed with the low-strength aromatic polyamide fiber yarn () has a tensile strength considerably higher than that of the aforementioned yarn (). Surprisingly, when the tensile strength is 15 to 40 g/d, for example, 2.0 times or more the tensile strength of the yarn, the resulting laminated sheet shows an extremely high tear strength. Then, the mixing ratio of high-strength aromatic polyamide fiber yarn () is 5 to 40.
A laminated sheet obtained by controlling the yarn density of 1000 denier or an equivalent yarn count to 1 to 9 threads per 2.54 cm (weight%) maintains a practically satisfactory tensile strength. be able to. In the laminated sheet of the present invention, the base fabric may be either a knitted fabric or a woven fabric, but in the case of a woven fabric, the warp and/or weft of the base fabric may be one containing aromatic polyamide fiber threads (). be. This aromatic polyamide fiber thread () is 10
g/d or less, preferably 3 to 10 g/d, and elongation at break of 10% or more, preferably 10 to 50%, although there are no particular limitations on the fineness. Generally, it is preferable to have a fineness of 100 to 1500 deniers. The yarn () may be spun yarn, monofilament yarn, multifilament yarn, or tape yarn, but is generally made of filament with a single fiber fineness of 1 to 15 deniers, more preferably 1.5 to 5 deniers. Preferably, it is a multifilament yarn. The aromatic polyamide constituting the aromatic polyamide fiber yarn () and/or () is at least
70 mol% of the following formulas () and (): (-Ar ₁ -CONH)- () and (-Ar ₁ -CONH-Ar ₂ -NHCO)- () [However, Ar ₁ and Ar ₂ are divalent represents an aromatic group, which may be the same or different. ] Preferably, the main repeating group is at least one selected from the following repeating groups. At this time, in the above formulas () and (), the divalent aromatic groups represented by Ar ₁ and Ar ₂ are:

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

[expression] and

[However, A represents -O-, -S-, -SO-, -SO ₂ -, -CO-, -CH ₂ -, or -C(CH ₃ ) ₂ -]

Preferably, it is selected from the group of aromatic residues represented by the following. These aromatic residues may contain inert substituents such as halogens, alkyl groups, nitro groups, and the like. Generally, the aromatic polyamide constituting the yarn () has the following repeating units: Preferably, it has as a main component. In general, the aromatic polyamide constituting the yarn () has the following repeating units: Preferably, it has as a main component. The base fabric used in the laminated sheet of the present invention is preferably made of a woven fabric containing aromatic polyamide fiber threads as warp and/or weft components. Although there are no particular limitations on the basis weight and structure of this fabric, it generally has a basis weight of 30 to 200 g/m ² and a warp density of 5 to 150 pieces/2.54 cm.
A woven fabric, particularly a plain woven fabric, having a weft density of 5 to 150 pieces/2.54 cm is preferred. Aromatic polyamide fiber yarn () is 15~40
It has a tensile strength of g/d and a breaking elongation of 1 to 8%, and it is particularly preferable that the tensile strength is 2.0 times or more the tensile strength of the aromatic polyamide fiber yarn. The tensile strength of the yarn () is
If it is less than 15 g/d, the tear strength of the resulting laminated sheet will be unsatisfactory. The shape of the yarn () may be spun yarn, monofilament yarn, multifilament yarn, or tape yarn, but generally it is composed of filaments with a single fiber fineness of 1 to 15 deniers and has a total fineness of 100 to 15. Preferably a 1500 denier multifilament;
Further, it is preferable that the thickness of the yarn (2) and the thickness of the yarn (2) mixed therewith are approximately equal, so that a laminated sheet having a flat surface can be obtained. In a base fabric made of a woven fabric, the threads () are inserted between the threads () one by one or in groups of two to five adjacent threads at intervals. At this time, the mixing ratio of threads () is preferably 5% or more but 40% or less, particularly preferably 1 to 8 threads per 2.54 cm, and more preferably 1 to 5 threads per 2.54 cm. When the blending ratio of yarns () is less than 5%, the tear strength of the resulting laminated sheet will be unsatisfactory. Further, even if the blending ratio of threads () is higher than 40%, the tear strength of the resulting laminated sheet does not improve much, and on the contrary, the abrasion resistance tends to decrease somewhat. In particular, when the yarn () has a small total fineness (e.g. 100-250 denier),
The mixing ratio of threads () should be 5% or more, but if the threads () have a large total fineness (for example,
500 to 1500 tenier), it is preferable that the blending ratio of yarn () is 5.0% or more. Further, each of the yarns () and () may be a single yarn, or may be a twisted yarn of two or more single yarns, or may be a drawn yarn. Further, each single yarn may be a non-twisted yarn or a twisted yarn. The yarn ( ) may be twisted together with the yarn ( ), or may be aligned. The woven structure of the base fabric used in the present invention is not particularly limited, but plain weave, oxford weave, leno weave, or other fabrics containing leno threads are generally used. Insertion of threads () between threads () is performed by inserting one thread () or two to five threads () adjacent to each other in parallel.
A group of threads () of a book are each a single thread ()
It is preferable that the fibers are arranged by separating the yarns or groups of 2 to 150 yarns (2 to 150 yarns) that are arranged adjacent to each other in parallel. In the laminated sheet of the present invention, a covering layer made of synthetic resin or synthetic rubber is formed on one side or both sides of the base fabric. The amount of the coating layer can be determined arbitrarily depending on the purpose of the coating and the type of coating material, but in general
Preferably, the weight is between 20 and 500 g/ ^m2 , and 50
More preferably, it is 300 g/m ² . The synthetic resin and synthetic rubber that form the coating layer can be arbitrarily selected depending on the purpose of the coating, but in general, polyvinyl chloride, ethylene-vinyl acetate copolymer, polyester, polyamide (such as nylon 12) are used for waterproofing. ), or polyolefins (polyethylene, polypropylene); for fireproofing, thermoplastic polymers such as polyimide, polyamideimide, polyether, polyketone, polysulfon; and synthetic rubbers such as silicone resins, polyphosphazenes and polyurethanes, and fluorine-containing resins. One or more types can be used. The synthetic resin or synthetic rubber that forms the coating layer is generally preferred to be highly elastic and flexible, but for fireproofing purposes thermosetting resins such as phenolic resins, epoxy resins, unsaturated polyester resins, polyimide resins, and triazine resins are preferred. , melamine resin, bis-diene polymer resin, etc., or a mixture of these and a thermoplastic resin. At this time, if a highly heat-resistant synthetic resin such as silicone resin, polyimide resin, polyamide-imide resin, polyphosphite resin, or fluorine-containing resin is used, the overall heat resistance will be improved along with the highly heat-resistant aromatic polyamide fiber base fabric. A laminated sheet with extremely good properties can be obtained. To form the coating layer on the base fabric, a solution or emulsion, sometimes a dispersion, or a film of the desired resin is applied to the desired surface of the base fabric using a conventional impregnation method, adhesion method, or coating method. All you have to do is give it to . Next, the present invention will be further explained by examples. Example: As aromatic polyamide fiber yarn ()
400d/48f Nomex (trademark) fiber yarn (cutting strength: 5.5 g/d, breaking elongation: 20%), and 400d/267f Kevlar fiber (trademark) as yarn ().
Seven types of plain woven fabrics having the following structures were woven using Dupont yarn (breaking strength: 22 g/d, breaking elongation: 4%) and varying the mixing ratio. 400d/1×400d/1/30/25.4mm
×30/25.4 mm threads () were inserted between the threads () at intervals, and the mixing ratio was as shown in Table 1. The obtained plain woven fabric was used as a base fabric, and after scouring and drying it in a conventional manner, RTV silicone rubber (Toshiba Silicone Corporation) was applied to the surface as a base coating agent.
A mixture of 10 parts by weight and 1 part by weight of crosslinking agent was coated using a knife coater to give a coating weight of 90 g/m ² . Next, heat this to 140℃
A heating cylinder heated to , and a linear pressure of 10
A top coat processing agent having the same composition as the base coat processing agent was added on the obtained base coat layer, which was passed through a heating calendar consisting of a pressure roller and a pressure roller that was pressed at a pressure of 1 kg/cm, and was brought into contact with the surface of the heating calendar for 45 seconds. was applied to a coating weight of approximately 10 g/m ² to prepare the surface condition, and heat treated at 180°C. Table 1 shows the tensile strength, tear strength, and durable wear resistance of the obtained laminated sheet.

[Table] In Table 1, the durable abrasion resistance of the products was determined as follows. That is, factory work aprons were made from each test laminated sheet, and factory workers were made to wear them for 6 months, and their appearance was evaluated. Excellent: Relatively little change in appearance and can still be used. Good: Can still be used, but has some wear. Defective: Items that have significant wear or tear and cannot be continued to be used. The following points are recognized from Table 1: (1) In the case of the laminated sheet (Sample 7) using a base fabric composed only of high-strength yarns (), its tensile strength was extremely excellent; The tear strength was unsatisfactory, and the durable abrasion resistance during actual use was poor. (2) In the case of the laminated sheet (Sample 1) using a base fabric composed only of low-strength yarns (2), its tensile strength was at a practical level, but its tear strength was significantly poor. Therefore, the durability during actual use was poor, and it was particularly unsuitable for applications where tearing force is applied. (3) The laminated sheet obtained using the base fabric of the present invention in which yarns () and yarns () are mixed at a predetermined mixing ratio has a tensile strength that is practically sufficient (15 kg/cm or more). It had extremely good tear strength, and therefore had excellent durability and abrasion resistance during actual use. That is, the obtained laminated sheets of Samples 2 to 6 according to the present invention are composed of a base fabric with excellent heat resistance and a heat-resistant resin coating layer, so they exhibit excellent heat resistance as a whole and are thin sheets. Therefore, it was excellent in practical use as a welding apron, etc., which was not only heat resistant but also easy to work with. These laminated sheets have a wide range of uses as sheets for heat-resistant work that is subject to wear and tear.

Claims (1)

[Claims] 1. The mixing ratio is 60 to 95% by weight, and 10
Aromatic polyamide fiber yarn () having a tensile strength of g/d or less and a breaking elongation of 10% or more, and a blending ratio of 5 to 40% by weight, and 15 to 40 g/d
a base fabric consisting of a knitted fabric made of aromatic polyamide fiber threads () having a tensile strength of d and a breaking elongation of 1 to 8%; and at least one of the base fabrics.
An aromatic polyamide fiber laminate sheet comprising a covering layer formed on a surface and made of synthetic resin or synthetic rubber. 2. The base fabric is made of a woven fabric containing the yarn () in warp and/or weft components, and the yarn ()
The laminated sheet according to claim 1, wherein the warp and/or weft includes 1 to 9 yarns per 2.54 cm. 3 Between the yarns (), one of the yarns ()
Or, groups of 2 to 5 yarns () arranged adjacent to each other are inserted at intervals,
A laminated sheet according to claim 2. 4. The laminated sheet according to claim 1, wherein the tensile strength of the yarn ( ) is 2.0 times or more the tensile strength of the yarn ( ). 5 The yarn () and/or the aromatic polyamide constituting the yarn () has at least 70 mol% of the following formula () and (): (-Ar ₁ --CONH)- () and (-Ar ₁ —CONH—Ar ₂ —NHCO)— () [However, Ar ₁ and Ar ₂ represent divalent aromatic groups, and these may be the same or different. ] The laminate sheet according to claim 1, which has at least one type selected from the following repeating groups. 6 In the above formulas () and (), the divalent aromatic group represented by Ar ₁ is [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] and [Formula] However, A is -O-, -S-, -SO-, -SO ₂
-, -CO-, -CH ₂ -, or -C(CH ₃ ) ₂ -. 7 In the above formulas () and (), the divalent aromatic group represented by Ar ₂ is [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] ] [However, A is -O-, -S-, -SO-, -SO ₂
-, -CO-, -CH ₂ -, or -C(CH ₃ ) ₂ -] The laminate sheet according to claim 5, wherein the laminated sheet is selected from the group of aromatic residues represented by -, -CO-, -CH 2 -, or -C(CH 3 ) 2 -. 8. The laminated sheet according to claim 1, wherein the yarn () has a tensile strength of 15 to 30 g/d and a breaking elongation of 1 to 8%. 9 The yarns () and () are each
The laminated sheet according to claim 1, having a fineness of 100 to 1500 deniers. 10. The laminated sheet according to claim 1, wherein the yarns () and () are each a spun yarn, a monofilament yarn, a multifilament yarn, or a tape yarn. 11 The above-mentioned single thread () or a group of 2 to 5 threads () arranged adjacently in parallel each other, or a group of 2 to 5 threads arranged adjacently in parallel 150
The laminated sheet according to claim 1, wherein the laminated sheet is arranged to separate the groups of threads of the book.