JPH09310209A - Rubber gloves - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a rubber glove that has excellent strength and oil resistance, is less likely to yellow due to chlorine treatment, and can suppress the occurrence of odors and allergies. SOLUTION: A rubber glove is manufactured by a latex dipping method using a mixed rubber latex of a deproteinized natural rubber latex and an acrylonitrile-butadiene copolymer rubber latex.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to rubber gloves.

[0002]

2. Description of the Related Art Conventional rubber gloves manufactured by the so-called latex dipping method are those made of natural rubber.
It was popular because of its low cost and high strength. In addition, the surface of the rubber gloves prevents the adhesion of the rubber films,
Powder such as cornstarch was sprinkled to make it easier to put on and take off rubber gloves.However, since the smell of powder or the adherence to the hands tends to be disliked in recent years, the treatment with the above powder should be used instead. Therefore, the surface of rubber gloves is treated with chlorine.

However, the rubber gloves made of natural rubber are not sufficiently resistant to various oils and organic solvents, and are easily yellowed by chlorine treatment, and the yellowed ones impair the cleanliness of appearance. There was a problem that Therefore, an acrylonitrile-butadiene copolymer rubber (NBR), which has excellent oil resistance and is less likely to yellow due to chlorine treatment, has been blended in natural rubber.

[0004]

However, the yellowing inhibitory action of NBR is still insufficient, and the NB
It has been clarified that the combined rubber containing R has a problem that the strength is lower than that of natural rubber. In recent years, the problem of allergies caused by the unique odor of proteins contained in natural rubber or the above proteins has come to the fore, and rubber gloves are required to be free from such odors and allergies. Has become.

An object of the present invention is to provide a rubber glove which has excellent strength and oil resistance, is less likely to yellow due to chlorine treatment, and can suppress the occurrence of odor and allergy.

[0006]

In order to solve the above problems, the present inventors have examined using deproteinized natural rubber (DPNR) instead of natural rubber. Ie DPN
R is a natural rubber processed to reduce the content of the above-mentioned characteristic odor and protein causing allergies. It is less likely to cause odors and allergies, and is higher than ordinary natural rubber. Since the strength is high, it is thought that it is possible to make up for the strength comparable to the rubber gloves made of natural rubber in the NBR compounding system by compensating for the decrease in strength due to the compounding of NBR.

Therefore, in practice, DPNR latex and N
Using rubber latex mixed with BR latex, rubber gloves were manufactured by the latex dipping method and their properties were examined. The manufactured rubber gloves were excellent in strength and oil resistance as intended, and also had a strong odor and allergic effect. It was revealed that, in addition to suppressing the generation, surprisingly, the yellowing due to chlorine treatment was also suppressed.

Therefore, the rubber glove of the present invention is the above-mentioned DPN.
It is characterized by being manufactured by a latex dipping method using a mixed rubber latex of R latex and NBR latex. The DPNR latex used in the present invention has a nitrogen content of 0.1%, which is an index of protein content, in view of the effects of suppressing the above-mentioned odor and allergy and the effect of suppressing yellowing due to chlorine treatment. It is preferably at most 05%.

The mixing ratio of the DPNR latex and the NBR latex is preferably within the range of 95/5 to 50/50 by weight. This is for the following reason.
That is, a rubber glove manufactured from a mixed rubber latex having a higher proportion of DPNR latex and a lower proportion of NBR latex than the above range has insufficient oil resistance and also has a problem that it tends to yellow due to chlorine treatment. May occur. Conversely, the DPN is higher than the above range.
Rubber gloves made from mixed rubber latex with a low proportion of R latex and a high proportion of NBR latex,
This may cause a problem of reduced strength.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below. As described above, the rubber glove of the present invention uses a mixed rubber latex of DPNR latex and NBR latex in a latex dipping method, that is, in the above mixed rubber latex containing various additives such as a vulcanizing agent, In a rubber glove mold, or a mold in which a glove body made of woven cloth, non-woven cloth, etc. is attached, immersed, then pulled up and further dried to form the surface of the mold or the woven cloth or non-woven cloth constituting the glove body. A rubber layer is formed on the surface of a glove or a glove body, and then the rubber layer is vulcanized.

The film forming process is performed once or twice or more depending on the layer structure of the rubber gloves. In addition to the film forming method by simply immersing in a mixed rubber latex, the film forming process includes a coagulating liquid method of aggregating rubber particles by using electrostatic force, a heat sensitive method using a rubber latex containing a heat sensitive coagulant, and the like. Can also be adopted.

Conditions such as temperature and time during film formation, drying, or vulcanization are appropriately set. Further, it is preferable that the surface of the manufactured rubber glove is treated with chlorine as described above. The conditions for chlorine treatment are the same as in the past. DPNR latex and NB in the above mixed rubber latex
The compounding ratio with R latex is 95/5 to 50 by weight.
It is preferably in the range of / 50. The reason is as described above. The mixing ratio of the DPNR latex and the NBR latex is 85/15 to 70 in terms of weight ratio, even within the above range, in view of further improvement of the above-mentioned properties and improvement of heat aging resistance of the rubber gloves. / 30
It is even more preferable that it is within the range.

DPNR used for mixed rubber latex
Examples of the latex include washing natural rubber latex such as field latex and purified natural rubber latex with water, degrading protein by adding bacteria or enzyme to the above natural rubber latex, adding alkali to the natural rubber latex and heating to heat the protein. It is possible to use any of those having a reduced protein content by various conventionally known methods such as degrading the protein, releasing the protein adsorbed on the rubber particles in the natural rubber latex with soaps, etc. .

However, as described above, as a DPNR latex in which the protein is highly removed so that the nitrogen content, which is an index of the protein content, is 0.05% or less, JP-A-6-56902. After the protein in the natural rubber latex is decomposed by the combination of one or more kinds of surfactants and protease disclosed in the publication, it is diluted with water and further centrifuged, ultrafiltration, etc. What was manufactured by the method of processing and concentrating is preferably used.

The above-mentioned nitrogen content is measured by the so-called Kjeldahl method, which utilizes the fact that the nitrogen content in protein is almost constant, and the nitrogen is entirely quantified as ammonium ions by heating with sulfuric acid. NBR used in mixed rubber latex with the above DPNR latex
As the latex, various grades can be used according to characteristics such as oil resistance required for gloves. Specific examples of such NBR latex include, but are not limited to, for example, trade name “LX5 manufactured by Nippon Zeon Co., Ltd.
20B ", a brand name" Butfan LN42 "manufactured by BASF.
6C ”and the like.

The additives to be mixed in the mixed rubber latex include, in addition to the above-mentioned vulcanizing agents, vulcanization accelerators, vulcanization accelerating aids (activators), antioxidants, fillers, dispersants, etc. Various conventionally known additives used for latex compounding can be mentioned. Among the above, examples of the vulcanizing agent include sulfur and organic sulfur-containing compounds, and the addition weight part thereof (addition weight part to 100 parts by weight of mixed rubber latex, the same applies hereinafter) is 0.5 to 1.5 parts by weight. It is preferably about 1 part.

As the vulcanization accelerator, for example, PX
(Zinc N-ethyl-N-phenyldithiocarbamate), PZ (zinc dimethyldithiocarbamate), EZ
(Zinc diethyldithiocarbamate), BZ (zinc dibutyldithiocarbamate), MZ (zinc salt of 2-mercaptobenzothiazole), TT (tetramethylthiuram disulfide), and the like, and one or more of them may be mentioned. It is preferable that the total amount of the added parts is 0.5 to 2.0 parts by weight.

Examples of the vulcanization accelerating aid include zinc white and the like, and the addition weight part thereof is preferably about 0.5 to 3.0 parts by weight. As an antiaging agent,
Non-polluting phenols are preferably used, but amines may also be used. The added weight part of the antioxidant is 1 to
It is preferably about 2 parts by weight.

Further, examples of the filler include kaolin clay, hard clay, calcium carbonate and the like, and the addition amount thereof is preferably 20 parts by weight or less. The dispersant is mainly for improving the dispersion of each of the above-mentioned additives in the mixed rubber latex, and examples of such a dispersant include casein and anionic surfactants. The addition amount of the dispersant is preferably about 2 to 5% by weight of the weight of the component to be dispersed.

In addition, for example, when the heat-sensitive method is adopted as the film-forming treatment, various additives other than those described above can be added to the mixed rubber latex, such as the addition of the heat-sensitive coagulant as described above. .

[0021]

The present invention will be described below with reference to examples and comparative examples. << Preparation of DPNR Latex (1) >> 18 kg of a 10% aqueous solution of sodium polyoxyethylene lauryl ether sulfate [E-70C manufactured by Kao Corporation] as a surfactant, and 200 kg of natural rubber high ammonia latex, and a proteolytic enzyme. (Protease) 80.4 g and water were added to prepare a latex having a rubber solid concentration of 30% by weight, and this latex was allowed to stand at 30 ° C. for 16 hours to decompose the protein.

Next, the above latex was diluted by adding water until the rubber solid content concentration became 10% by weight, and then a disk type centrifuge (LR510 manufactured by Alfa Laval Co., Ltd. was used.
Type) was continuously concentrated by centrifugation to produce DPNR latex (1) having a rubber solid content of 60% by weight. When the nitrogen content of the DPNR latex (1) was measured by the Kjeldahl method described above, it was 0.0
It was 45%. << Preparation of DPNR Latex (2) >> A latex obtained by decomposing proteins in the same manner as in the preparation of DPNR latex (1) was added to a 10% sodium carbonate aqueous solution 240k.
g, and after further diluting by adding water until the rubber solid content concentration becomes 10% by weight, the rubber solid content concentration is 60 by continuous centrifugation using the above-mentioned disc type centrifuge. It concentrated until it became weight%.

Next, the above-mentioned latex was again diluted by adding water until the rubber solid content concentration became 10% by weight.
DPNR having a rubber solid concentration of 60% by weight, which is continuously concentrated using a disk centrifuge and concentrated by centrifugation.
A latex (2) was produced. The above DPNR latex
The nitrogen content in (2) was 0.015% as measured by the Kjeldahl method described above.

In addition, the infrared absorption spectrum of the above DPNR latex (2) was measured. As a result, absorption at a wave number of 3280 cm ^-1 peculiar to a polypeptide showing the presence of a protein was not recognized. << Manufacture of Rubber Gloves >> Examples 1 to 4 DPNR latex (1) and NBR latex [LX520B manufactured by Nippon Zeon Co., Ltd. mentioned above] in a weight ratio shown in Table 1 100 weight of mixed rubber latex To 1 part by weight, 1 part by weight of sulfur, 1 part by weight of vulcanization accelerator BZ, and 0.5 part by weight of zinc white were added.

Next, the mixed rubber latex was mixed with 70
The glove mold heated to ℃ was immersed, then pulled up and dried at room temperature for several minutes to form a rubber layer on the surface of the mold. Then, this rubber layer was placed in an oven at 120 ° C. for 3 times.
The rubber gloves were manufactured by vulcanizing for 0 minutes.

Comparative Example 1 Rubber gloves were manufactured in the same manner as in Examples 1 to 4 except that NBR latex was not blended, that is, only 100 parts by weight of DPNR latex (1) was used. Comparative Example 2 DPNR latex (1) was not blended, that is, NB
Rubber gloves were manufactured in the same manner as in Examples 1 to 4 except that only 100 parts by weight of R latex was used.

With respect to the rubber gloves of the above Examples and Comparative Examples, the following tests were carried out to evaluate their characteristics. Tensile Property Test The rubber gloves of Examples and Comparative Examples were punched out, and ASTM D
Test piece for tensile test (thickness 0.1
1 to 0.12 mm) was produced. And using this test piece, in accordance with the test method Shosai to ASTM D-412, stress M ₃₀₀ Tensile when 300% elongation, stress M ₅₀₀ Tensile when 500% elongation, elongation at break E _B, and tensile Strength T
I asked for _B.

Tensile property test after heat aging The rubber gloves of Examples and Comparative Examples were heat-aged at 100 ° C. for 22 hours, and then a test piece was prepared in the same manner as described above. Similarly, tensile stress M ₃₀₀ (MPa) at 300% elongation, tensile stress M at 500% elongation
₅₀₀ (MPa), elongation at break E _B (%), and tensile strength T _B (MPa) were determined.

Oil resistance test The rubber gloves of Examples and Comparative Examples were punched into strips to give test pieces. The test pieces were immersed in toluene at 40 ° C for 24 hours for swelling, and then the mass was measured. The swelling ratio was calculated by the following formula, and the oil resistance was evaluated.

[0030]

[Equation 1]

Chlorine Treatment Test After the rubber gloves of Examples and Comparative Examples were chlorinated, the color difference based on Comparative Example 1 before chlorine treatment was measured using a color difference meter [CR300 manufactured by Minolta Co., Ltd.]. . Further, the rubber gloves after the chlorine treatment were heat aged at 100 ° C. for 22 hours, and then the color difference based on Comparative Example 1 before the chlorine treatment was measured in the same manner as above. Then, from the above color difference, the intensity of yellowing due to chlorine treatment was evaluated.

The slipperiness when the rubber gloves after the chlorine treatment were actually put on the hands was evaluated according to the following criteria. ⊚ ... Slip feeling is particularly good, ◯ ... Slip feeling is good, × ... Slip feeling is poor. The above results are shown in Table 1.

[0033]

[Table 1]

From the results shown in Table 1, DPNR latex (1)
And NBR latex in a weight ratio of 95/5 to 50/5
The rubber gloves of Examples 1 to 4 used together in the range of 0 were DPN.
Compared with Comparative Example 1 using only R latex (1), it is superior in oil resistance, less likely to be yellowed by chlorine treatment, and has better tensile properties than Comparative Example 2 using only NBR latex. all right. Further, comparing the above-mentioned respective examples, the rubber gloves of Examples 2 and 3 in which DPNR latex (1) and NBR latex were used together in a weight ratio range of 85/15 to 70/30 had the above preferable range. It was found that the yellowing was further less likely to occur due to the chlorine treatment as compared with the detached Example 1, and the tensile properties after heat aging were superior to those of the Example 4 as well.

Example 5 DPNR Latex Instead of DPNR Latex (1)
(2) is used, and such DPNR latex (2) and NBR are used.
Latex [LX520B manufactured by Nippon Zeon Co., Ltd.]
Rubber gloves were produced in the same manner as in Examples 1 to 4, except that and were blended in a weight ratio of 50/50.

Comparative Examples 4 and 5 In place of the DPNR latex (1), untreated natural rubber high ammonia latex (NR latex) was used, and the NR latex and the NBR latex [manufactured by Nippon Zeon Co., Ltd. mentioned above] were used. LX520B] in a weight ratio of 70
/ 30 (Comparative Example 4) or 50/50 (Comparative Example 5), except that it was compounded in the same manner as in Examples 1 to 4, to produce a rubber glove.

Comparative Example 3 Comparative Example 4, except that no NBR latex was blended, that is, only 100 parts by weight of NR latex was used.
A rubber glove was manufactured in the same manner as in 5. With respect to the rubber gloves of each of the above-mentioned Examples and Comparative Examples, the above-mentioned respective tests were conducted and the characteristics thereof were evaluated. The results, together with the results of Example 4 above,
It shows in Table 2.

[0038]

[Table 2]

The results of Comparative Examples 3 to 5 shown in Table 2 are the same as those of Comparative Example 1 in which the compounding amounts of NBR latex were the same.
Comparing with the results of Examples 3 and 4, it was found that by using DPNR latex (1) in place of NR latex, tensile properties were improved and yellowing due to chlorine treatment could be suppressed. In addition, Comparative Example 5 and Examples 4 and 5 in Table 2
Comparing these results, it was found that the smaller the nitrogen content, which is an index of the protein content, the more the yellowing due to chlorine treatment can be suppressed.

[0040]

As described above in detail, according to the present invention, there is provided a rubber glove which is excellent in strength and oil resistance, is hard to be yellowed by chlorine treatment, and can suppress the generation of odor and allergy. be able to.

Claims (3)

[Claims] 1. A rubber glove manufactured by a latex dipping method using a mixed rubber latex of a deproteinized natural rubber latex and an acrylonitrile-butadiene copolymer rubber latex. 2. The rubber glove according to claim 1, wherein the deproteinized natural rubber latex has a nitrogen content of 0.05% or less. 3. The blending ratio of the deproteinized natural rubber latex and the acrylonitrile-butadiene copolymer rubber latex in the mixed rubber latex is 95/5 to 5 by weight.
The rubber glove according to claim 1, which is in the range of 50/50.