JP2013213299A - Resin-made glove - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin-made glove, hardly causing contamination from the raw material itself and excellent in incision resistant properties.SOLUTION: An LLDPE having ≥15 newton through-hole strength, when a needle with a 0.5 mm diameter is perpendicularly pierced at 50 cm/min velocity from a surface in a strength test based on JISZ-1707, is used. The LLDPE is polymerized by a low pressure polymerization method by adding an α-olefin as a comonomer to a polyethylene, however, and in order to obtain good slipperiness in wearing and sufficient through-hole strength, an LLDPE polymerized by using a metallocene-based catalyst is preferable. An LLDPE copolymerized with a ≥6C α-olefin as a comonomer is a resin having the through-hole strength together with flexibility, and therefore it is preferable as the raw material for the resin-made glove.

Description

  The present invention relates to a resin glove, and more particularly to a resin glove suitable for preventing cuts and preventing contamination when handling a polycrystalline silicon lump or the like.

  A polycrystalline silicon lump is produced by pulverizing a polycrystalline silicon rod obtained by supplying silane or the like as a source gas and depositing it on a silicon core wire by the Siemens method or the like. Such a polycrystalline silicon lump is used for production of a single crystal silicon ingot by the CZ method, production of a substrate for a solar cell, or the like.

  The polycrystalline silicon lump obtained by pulverization is subjected to a sorting operation or the like according to the use, but these operations are hardly automated. Sorting, inspection, and packing are performed mainly by manual work. At this time, gloves are used for cutting prevention and surface contamination.

  However, as described in Patent Document 1 (Japanese Patent Application Publication No. 2010-528955), even if an operator wears a high-purity polyethylene (PE) glove and handles crushed polycrystalline silicon, the glove For reasons such as rubbing, the content of plastic particles and metal particles on the polycrystalline silicon crushed material increases and causes contamination.

  In addition, Patent Document 2 (Japanese Patent Laid-Open No. 2011-80190) discloses that ultra high-purity polyethylene (PE) gloves suitable for preventing pollution are poor in cut resistance, and therefore workers frequently check for damage to PE gloves. There is a need. Moreover, when damage is overlooked, it points out the problem that human sweat containing sodium chloride contaminates high-purity silicon and cannot be used as a high-purity silicon material.

Special table 2010-528955 gazette JP 2011-80190 A JP-A-3-269103

  As described above, there is room for improvement in the anti-contamination gloves used for the handling work of the polycrystalline silicon lump, and in particular, it has excellent cut resistance that is unlikely to be damaged during the handling work of the polycrystalline silicon lump. Gloves are sought.

  The present invention has been made in view of such demands, and an object of the present invention is to provide a resin glove that hardly causes contamination from the material itself and has excellent cut resistance.

  In order to solve the above-mentioned problems, the resin glove of the present invention is made of linear low-density polyethylene, and in a strength test based on JISZ-1707, a needle having a diameter of 0.5 mm from the surface at a speed of 50 cm / min. The through-hole strength when pierced vertically is 15 Newton or more.

  Preferably, the linear low density polyethylene is a resin polymerized with a metallocene catalyst.

  Preferably, the linear low density polyethylene is a copolymer of an α-olefin having 6 or more carbon atoms.

  Further preferably, the thickness of the film is 0.5 mm or less.

  The resin glove according to the present invention is a linear low-density polyethylene, so that it is difficult to contaminate the object to be handled, and has a through hole strength of 15 Newtons or more in a strength test according to JISZ-1707. Therefore, it has excellent cut resistance.

  For this reason, it is suitable for the handling work of the polycrystalline silicon lump etc. which require high purity, and the work efficiency is also improved because it is not necessary to frequently replace the gloves.

  In the glove for resin according to the present invention, the part that touches the object to be handled in a state worn by the operator is made of linear low density polyethylene (LLDPE). LLDPE is a thermoplastic resin in which ethylene and α-olefin are copolymerized. In low-density polyethylene (LDPE), repeating units of ethylene are randomly branched and bonded, whereas LLDPE is of repeating units. Ethylene has little branched structure.

  Since LLDPE is harder than LDPE, it is inferior in flexibility when used as a glove, but on the other hand, its tensile strength is higher than that of LDPE and it has excellent through-hole strength.

  A glove made of LLDPE has already been proposed in Patent Document 3 (Japanese Patent Laid-Open No. 3-269103). However, if it exceeds 200 μm, the workability deteriorates, and the preferable thickness is 20 to 100 μm. Also in the examples, an LLDPE film having a thickness of 70 μm is used. However, a resin glove having such a thickness is insufficient in strength as a glove when handling a high purity polycrystalline silicon lump.

  Therefore, in the present invention, LLDPE having a through hole strength of 15 Newton or more when a needle having a diameter of 0.5 mm is vertically stabbed from the surface at a speed of 50 cm / min in a strength test based on JISZ-1707 is used.

  In order to secure the penetration strength, when the resin glove of the present invention is produced from LLDPE distributed as a film, the thickness of the film is preferably 0.12 mm or more. On the other hand, the thickness of the film is preferably 0.5 mm or less so as not to significantly reduce workability due to lack of flexibility.

  LLDPE is a polymer obtained by adding α-olefin as a comonomer to polyethylene and polymerizing by low pressure polymerization method. In order to obtain good slipperiness during mounting and sufficient penetration strength, a metallocene catalyst is used. Polymerized LLDPE is preferred.

  LLDPE obtained by copolymerizing an α-olefin having 6 or more carbon atoms as a comonomer is a resin having both through-hole strength and flexibility, and thus is preferable as a material for the resin glove of the present invention. In addition, LLDPE obtained by copolymerizing α-olefin having about 6 to 8 carbon atoms as a comonomer can be easily obtained.

  In the resin glove according to the present invention, the part touching the object to be handled in a state worn by the operator may be composed of the above-described LLDPE having the through-hole strength, and the other part is composed of another material. May be. Moreover, the aspect comprised by LLDPE on the other raw material other than the aspect comprised only by LLDPE may be sufficient as the part comprised by LLDPE.

  Furthermore, it is good also as an aspect which made the glove a multi-structure, made the disposable glove which comprised the surface side by the above-mentioned LLDPE, and made the inner glove which consists of another raw material inside. In this case, it is only necessary to replace the front side gloves that have been contaminated or cut by long-term use.

The resin glove which concerns on this invention can be produced in the following processes, for example. First, the LLDPE film is subjected to acid cleaning, rinsing, and drying in a clean room to remove surface foreign matters and metal deposits. For example, it is immersed in a 0.1N-HNO ₃ aqueous solution for 30 seconds, washed with acid, rinsed with ultrapure water, further washed with pure water, and then allowed to stand and dry.

  Next, two LLDPE films cleaned in the above process are layered, and the entire circumference including the insertion part of the hand is 10 mm so that it forms a glove that covers from the hand to the elbow of the operator by ultrasonic heating. Heat welding with width.

  Further, the glove is cut out from the film with a sharp cutter so that the cut portion does not become a source of plastic dust, and the above-described acid cleaning, rinsing and drying are performed again to remove foreign matters and metal impurities.

  In the cleaning, rinsing, and drying steps after forming the glove, it is not essential to perform the same treatment on the inside of the glove. Therefore, the part where the operator inserts his / her hand may be left in a welded state, and the welded part may be cut off and used when the operator wears it.

  The resin glove according to the present invention is suitable for work for handling polycrystalline silicon, but is particularly useful for sorting and packing work for crushed polycrystalline silicon mass after acid cleaning.

  When performing such an operation, it is preferable to wear an inner glove made of a low dusting material that can be used in a clean room, such as nylon or a natural material, and then wear a glove made of LLDPE. Since the surface of the LLDPE glove has a high through-hole strength, it is difficult for the glove to break during work, and it is not necessary to frequently check the deterioration state.

  For example, when a normal crushed polycrystalline silicon lump sorting operation or the like is performed, an amount of about 100 kg can be processed without changing gloves. In addition, according to the observations of the present inventors, when the work is performed while wearing a conventional clean clean disposable glove for a clean room, the glove is colored with silicon powder during the work, but the LLDPE made of the present invention is used. In the case of gloves, such coloration hardly occurs during work. This is probably because the LLDPE gloves themselves have high resistance to contamination by foreign substances and metals.

[Experimental Example 1] Measurement of Through-hole Strength Using an LLDPE or LDPE film as a sample, a needle having a diameter of 0.5 mm was pierced vertically at a speed of 50 cm / min into an area of 3 cm in diameter of a film cut into 10 cm × 10 cm. At this time, a tension meter (Shimadzu Corporation small table tester EZTest-10N) is connected to the needle.

  It was confirmed that the sample was damaged by this piercing, and the maximum value of the tension was taken as the through-hole strength from the record of the recorder. The measurement was repeated 5 times for each sample, and the average value was adopted. Table 1 summarizes the penetration strength (Newton) and film thickness (μm) for each sample.

  Here, LLDPE-1 is a metallocene polymerized ethylene: 1-octene copolymer (Evolution manufactured by Prime Polymer), and LLDPE-2 is a metallocene polymerized ethylene: 1-hexene copolymer. (Prime Polymer, Moiretec). Further, all of LDPE-1 to LDPE-4 are low-pressure polymerization polyethylene (detailed material unknown).

  As shown in Table 1, the LLDPE film has higher penetration strength than the LDPE film. Although the LLDPE film has a high hardness, sufficient flexibility as a glove can be secured by reducing the thickness. For example, in the case of an LLDPE film having a thickness of 150 μm, in a strength test according to JISZ-1707, the penetration strength when a needle with a diameter of 0.5 mm is vertically pierced from the surface at a speed of 50 cm / min is 15 Newton. Thus, both workability and strength can be achieved.

[Example 1 and Comparative Examples 1 to 3]
Gloves are prepared using the LLDPE-1 film and LDPE-1 to 3 films used in Experimental Example 1, and these gloves are attached to handle the polycrystalline silicon lump. And the degree of metal contamination on the surface of the polycrystalline silicon lump was measured.

  In addition, the operator carried out work by wearing an inner glove made of woolly nylon for clean room and wearing the glove (Example 1 and Comparative Examples 1 to 3) thereon.

  Subsequently, 5 kg of silicon lump, which is mainly about 50 g per piece, was packed into a clean polyethylene bag. Every time 5kg packaging was completed, the condition of the glove was carefully observed visually, and the presence or absence of pinholes and cuts was confirmed to examine the durability of the glove. The results are summarized in Table 2.

  As for metal contamination on the surface of the polycrystalline silicon lump, 150 g of each sample is taken out from the silicon lump before the work and the silicon lump packed by the worker wearing each glove, and the surface contamination is measured by the following method. Then, the change in the amount of metal impurities was determined.

First, 150 g of a polycrystalline silicon sample was transferred to a 500 ml clean Teflon (registered trademark) beaker, and a surface metal extract 200 ml consisting of 100 ml of 50% HF aqueous solution, 99 ml of ultrapure water, and 1 ml of 30% hydrogen peroxide water was added. Heat extraction was performed at 95 ° C. for 10 minutes. After extraction, 1 ml of the extract is dispensed into a clean Teflon (registered trademark) container, heated and evaporated to dryness, 1 ml of 1% HNO ₃ is added, and each metal element is dissolved by ICP-MS (Agilent 7500). Was quantified. The results are summarized in Table 3. The unit is pptw.

  From Tables 2 and 3, it can be seen that the gloves made of LLDPE exhibit high durability and are less likely to cause metal contamination on the handled polycrystalline silicon.

  The resin glove according to the present invention is a linear low-density polyethylene, so that it is difficult to contaminate the object to be handled, and has a through hole strength of 15 Newtons or more in a strength test according to JISZ-1707. Therefore, it has excellent cut resistance. For this reason, it is suitable for the handling work of the polycrystalline silicon lump etc. which require high purity, and the work efficiency is also improved because it is not necessary to frequently replace the gloves.

Claims (4)

  It consists of linear low density polyethylene, and in the strength test according to JISZ-1707, the penetration strength when a needle with a diameter of 0.5 mm is vertically pierced from the surface at a speed of 50 cm / min is 15 Newton or more. Resin gloves.   The resin glove according to claim 1, wherein the linear low density polyethylene is a resin polymerized by a metallocene catalyst.   The resin-made glove according to claim 1 or 2, wherein the linear low-density polyethylene is obtained by copolymerizing an α-olefin having 6 or more carbon atoms.   The resin glove according to any one of claims 1 to 3, wherein the film has a thickness of 0.5 mm or less.