JP2000290814A - Nbr glove - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible NBR (acrylonitrile-butadiene rubber) glove having both oil resistance and toughness of the NBR skin itself, thereby causing a flexibilizer incorporated therein not to ooze onto the surface of the skin as having been seen so far. SOLUTION: This NBR glove is obtained by molding an NBR latex as raw material prepared by formulating 100 pts.wt., on a solid basis, of an NBR latex with 5-50 pts.wt. of a copolymer from 94-75 mol% of an alkyl acrylate, 5-20 mol% of acrylonitrile, and 1-5 mol% of acrylic or methacrylic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to gloves made of NBR for home use and work, which are manufactured by a dipping method or a coating method.

[0002]

2. Description of the Related Art Gloves made of NBR (acrylonitrile butadiene rubber) are more oil- and grease-resistant than gloves made of NR (natural rubber) and PVC (polyvinylchloride). It has excellent properties such as piercing and abrasion resistance. On the other hand, gloves made of NBR have a drawback that they have extremely low rebound resilience and lack flexibility compared to NR, and they are slippery on the glove surface when grasping an object. Was often viewed as a problem. In order to remedy this drawback, attempts have conventionally been made to soften the composition by adjusting the blending of a vulcanizing agent or by adding a softener.

[0003]

In the preparation of vulcanizing agents, various agents are provided as vulcanizing agents for NBR. However, sulfur (S) and zinc oxide (ZnO) are mainly used in combination. Generally, the strength and flexibility of an NBR film formed by vulcanization are greatly affected by the number of parts of sulfur (S) and zinc oxide (ZnO). NB for home and work
In the vulcanization system blended in R gloves, the total blended amount of sulfur (S) and zinc oxide (ZnO) is often used in the range of usually 2 to 5 parts by weight, and the tensile strength of the film is strong. Yes, but generally low flexibility, especially in low temperature range (around 0 ° C)
Then it is hard.

[0004] Therefore, the inventors of the present invention have repeatedly studied and found that both the flexibility and the slipperiness of the glove surface are related to the physical properties of the glove film, and the slipperiness is determined by the glove surface film when the object is gripped. It has been demonstrated that the contact area between the glove and the object surface becomes larger, that is, the softness of the glove surface film is greatly related. Among them, the total blending amount of sulfur (S) and zinc oxide (ZnO) is used in the range of 1 to 2 parts by weight, and the 100% modulus value is set to 20 kg / cm ² or less to improve the slip prevention effect. However, this method alone has a disadvantage that it is difficult to obtain sufficient strength as a glove film.

As the softener, adipate plasticizers, mineral oils, vegetable oils, and the like are often used, and when added in small amounts, greatly contribute to softening.
There was a problem that the material gradually moved to the surface of the glove and became very slippery when working in a water leak situation. The present invention has been made to solve such problems, and has an object to provide a soft NBR glove having an oil resistance and toughness of an NBR film main body and a softener not eluting to the film surface. Is what you do.

[0006]

Means for Solving the Problems The present inventors have developed a home-use,
NBR with film strength enough to be practically used as a working NBR glove and flexibility not found in conventional NBR films
He worked diligently to develop latex blend glove compositions. From the viewpoint of imparting flexibility, the polymer latex has good compatibility with the NBR latex, can be easily blended, and has a soft segment in the molecule, for example, SBR,
As a result of searching mainly for acrylics and the like, it was found that an alkyl acrylate copolymer was obtained, and in particular, alkyl acrylate: 94 to 75 mol%, acrylonitrile;
The inventors have found that a copolymer latex having a monomer composition of 20 mol%, acrylic acid or methacrylic acid; 1 to 5 mol% is the most suitable blend material for the purpose, and completed the present invention.

That is, the glove made of NBR of the present invention
94 to 75 mol% of alkyl acrylate and 5 to 20 of acrylonitrile based on 100 parts by weight of R latex solid
It is characterized by being molded using an NBR latex containing 5 to 50 parts by weight of a copolymer of 1 to 5 mol% of acrylic acid or methacrylic acid as a material. The NBR latex used in the present invention is a so-called low to high acrylonitrile NBR, which contains 20 to 45 mol% of acrylonitrile and has a carboxyl-modified group of 10% or less, and is generally used as a glove material. A range of molecular weights can be used.

If the copolymer is less than 5 parts by weight with respect to 100 parts by weight of the solid content of the NBR latex, sufficient flexibility cannot be obtained, and if it exceeds 50 parts by weight, sufficient film strength as a glove material is not obtained. Since it cannot be obtained, it is appropriate to blend 5 to 50 parts by weight of the copolymer. There is no particular limitation on the molecular weight of the copolymer. Ethyl acrylate, n-butyl acrylate, iso-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, and the like are effective as the alkyl acrylate that is a flexible segment. The content is desirably high, but it is the balance of acrylonitrile and acrylic acid or methacrylic acid.

Acrylonitrile is an important component for compatibility with NBR latex. If the amount is less than 5 mol%, compatibility with NBR is greatly unsuitable, and
If it exceeds mol%, the blend film with NBR becomes hard,
Since the original purpose, that is, the purpose as a softening agent, cannot be achieved, an amount sufficient to be compatible and 5 to 20 mol% that does not impair the flexibility of the molecule is appropriate.

[0010] The acrylic acid or methacrylic acid component is a component necessary for stabilizing the latex.
It is important in film forming strength when blended into terrax and formed by heating, and NBR molecules and alkyl acrylate copolymer molecules are chemically formed by ZnO (zinc oxide) blended as a vulcanizing agent for NBR terrax. It binds and serves to prevent the alkyl acrylate copolymer from phase separation or elution from the NBR latex blend coating. For this reason, the role of acrylic acid or methacrylic acid in the acrylic alkylate copolymer is important.
When the amount of acrylic acid or methacrylic acid is less than 1 mol%, it is insufficient to chemically bond and integrate with NBR molecules, and the strength of the NBR blend film tends to be extremely lowered. On the other hand, if it exceeds 5 mol%, the hardness of the formed film becomes high, which is unsuitable as a target flexible glove material. Here, the use of maleic dibasic acid, which can be polymerized in the same manner as acrylic acid or methacrylic acid, can be considered, but the alkyl acrylate copolymer obtained by polymerizing them has poor compatibility with the NBR latex, and the purpose is achieved. Therefore, it is limited to acrylic acid or methacrylic acid.

In the production of gloves made of NBR, a dipping process or a coating process is performed using NBR latex containing the above-mentioned components as a material.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments, but the present invention is not limited to these. Embodiment 1 A ceramic glove mold was immersed in a 30% calcium nitrate methanol solution, then immersed in an NBR latex compound having the following composition (1) for 30 seconds, pulled up, and pulled up to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. The surface area change rate, tensile strength, and 100% modulus of the NBR glove were measured and calculated using a test piece cut from the glove hem. Table 1 shows the result data.
Shown in However, NBR latex in the compounding material is Nip
pol LX551 (manufactured by Nippon Zeon Co., Ltd .; the same applies hereinafter), and nBA-AN-AA copolymer latex is n-butyl acrylate; 94 mol% -acrylonitrile; 5 mol% -acrylic acid; 1 mol% copolymer latex And having a molecular weight of about 250,000, both of which are indicated by solid content weight.

Formulation (1) NBR latex 80 parts by weight nBA-AN-AA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 part by weight Antioxidant 1 part by weight Pigment proper amount Form 2 A ceramic glove mold is immersed in a methanol solution of 30% calcium nitrate, then immersed in an NBR latex compound having the following composition (2) for 30 seconds, pulled up, and heated to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. The surface area change rate, tensile strength, and 100% modulus of the NBR glove were measured and calculated using a test piece cut from the glove hem. Table 1 shows the result data.
Shown in However, nBA-AN-AA copolymer latex in the compounding raw material is n-butyl acrylate; 90 mol%
Acrylonitrile; 5 mol% -acrylic acid; 5 mol% copolymer latex having a molecular weight of about 200,000.

Formulation (2) NBR latex 80 parts by weight nBA-AN-AA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 parts by weight Antioxidant 1 part by weight Pigment proper amount Form 3 A ceramic glove mold is immersed in a methanol solution of 30% calcium nitrate, then immersed in an NBR latex compound having the following composition (3) for 30 seconds, and pulled up to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. Further, the surface area change rate, the tensile strength, and the 100% modulus of the NBR glove were measured using a test piece cut from the glove hem. Table 1 shows the result data. However, the nBA-AN-AA copolymer latex in the compounding raw material is a copolymer latex of n-butyl acrylate; 79 mol% -acrylonitrile; 20 mol% -acrylic acid; 1 mol%, and has a molecular weight of about 300,000. It is.

Formulation (3) NBR latex 80 parts by weight nBA-AN-AA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 part by weight Antioxidant 1 part by weight Pigment proper amount Form 4 A glove mold made of ceramic is immersed in a methanol solution of 30% calcium nitrate, then immersed in an NBR latex compound having the following composition (4) for 30 seconds, and pulled up to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. The surface area change rate, tensile strength, and 100% modulus of the NBR glove were measured and calculated using a test piece cut from the glove hem. Table 1 shows the result data.
Shown in However, the nBA-AN-MA copolymer latex of the compounding raw material is n-butyl acrylate; 94 mol%
5% by mole of acrylonitrile; 1% by mole of methacrylic acid; a copolymer latex having a molecular weight of about 300,000.

Formulation (4) NBR latex 80 parts by weight nBA-AN-MA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 part by weight Antioxidant 1 part by weight Pigment proper amount Form 5 A ceramic glove mold is immersed in a 30% calcium nitrate methanol solution, then immersed in an NBR latex compound having the following composition (5) for 30 seconds, pulled up, and pulled up to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. Further, the surface area change rate, the tensile strength, and the 100% modulus of the NBR glove were measured using a test piece cut from the glove hem. Table 1 shows the result data. However, the 2EA-AN-AA copolymer latex of the compounding raw material is a copolymer latex of 2-ethylhexyl acrylate; 94 mol% -acrylonitrile; 5 mol% -acrylic acid; 1 mol%, having a molecular weight of about 250,000. It is.

Formulation (5) NBR latex 80 parts by weight 2EHA-AN-AA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 part by weight Antioxidant 1 part by weight Pigment appropriate amount Perform Form 6 A ceramic glove mold is immersed in a methanol solution of 30% calcium nitrate, then immersed in an NBR latex compound having the following composition (6) for 30 seconds, and pulled up to 80 ° C. × 20.
After drying for min, heat treatment was performed at 130 ° C. × 1 hr, and the mold was inverted and released from a hand mold to produce a prototype NBR glove. A test piece (63.5 mm x 63.5 m) was taken from the palm of this glove.
m), measure the dynamic friction coefficient under wet conditions,
Calculated. The surface area change rate, tensile strength, and 100% modulus of the NBR glove were measured and calculated using a test piece cut from the glove hem. Table 1 shows the result data.
Shown in However, the EA-AN-AA copolymer latex of the compounding raw material is a copolymer latex of ethyl acrylate; 94 mol% -acrylonitrile; 5 mol% -acrylic acid; 1 mol%, and has a molecular weight of about 250,000. .

Formulation (6) NBR latex 80 parts by weight EA-AN-AA copolymer latex 20 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 part by weight Antioxidant 1 part by weight Pigment appropriate amount comparison Example 1 In the same manner as in Embodiment 1, a ceramic glove mold was immersed in a 30% calcium nitrate methanol solution, then immersed in an NBR latex compound having the following composition (7) for 30 seconds, pulled up and dried at 80 ° C. × 20 minutes. After one
A heat treatment was performed at 30 ° C. × 1 hr, and the mold was inverted and released from the hand mold to produce a prototype NBR glove. A test piece (63.5 mm × 63.5 mm) was cut out from the palm of this glove, and the dynamic friction coefficient under wet conditions was measured and calculated. Further, the surface area change rate, the tensile strength, and the 100% modulus of the NBR glove were measured using a test piece cut from the glove hem. Table 1 shows the result data.

Formulation (7) NBR latex 100 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 parts by weight Antioxidant 1 part by weight Pigment appropriate amount Comparative Example 2 Ceramics as in the first embodiment After the glove mold was dipped in a 30% calcium nitrate methanol solution, it was dipped in an NBR latex compound having the following composition (8) for 30 seconds, pulled up and dried at 80 ° C. for 20 minutes.
A heat treatment was performed at 30 ° C. × 1 hr, and the mold was inverted and released from the hand mold to produce a prototype NBR glove. A test piece (63.5 mm × 63.5 mm) was cut out from the palm of this glove, and the dynamic friction coefficient under wet conditions was measured and calculated. Further, the surface area change rate, the tensile strength, and the 100% modulus of the NBR glove were measured using a test piece cut from the glove hem. Table 1 shows the result data.

Formulation (8) NBR latex 100 parts by weight Adipate ester plasticizer 10 parts by weight Zinc oxide 2 parts by weight Sulfur 1 part by weight Vulcanization accelerator 0.5 parts by weight Antioxidant 1 part by weight Pigment appropriate amount Measurements, calculations, and evaluations based on the forms 1-4 and Comparative Examples 1-3 were performed as follows. Measurement and Calculation of Dynamic Friction Coefficient Based on ASTM D 1894, an NBR film test piece cut from a glove palm was attached to a moving weight using a friction coefficient measuring apparatus, and a stainless steel plate filled with a certain amount of water was placed on a moving stainless steel plate.
After running at a moving distance of 130 mm at a speed of 50 mm / min, a load that changes due to friction between the test piece and the stainless steel plate is measured, and a running resistance (dynamic friction coefficient) is calculated.

Contact area of moving weight 63.5 mm × 63.5 mm Calculation formula μK (dynamic friction coefficient) = C / D C = average load value (g) after uniform running D = weight of moving weight 200 g Measurement of tensile strength and 100% modulus A test piece (63.5 mm × 6
3.5mm), cut out 4 pieces, tensile strength and 100%
The modulus was measured according to JIS K6301. Measurement of surface area change rate A square test piece with a side of 5 cm is cut out from the smooth part of the NBR glove, and immersed in gasoline at a liquid temperature of 23 ° C. for 1 hour and 2 hours. to measure the 1 _a · 1 _B after the wipe off the excess gasoline was determined the surface area change rate%.

The surface area change rate is calculated by the following equation.
Round to one decimal place according to JIS Z8401. _{ΔA = (1 A · 1 B} / 1 a · 1 b -1) × 100 ΔA; surface area rate of change _{(%) 1 A · 1 B} ; diagonal length after immersion _{(mm) 1 a · 1 b} ; Immersion Previous diagonal length (mm) Evaluation of anti-slip It was determined that the larger the value of the dynamic friction coefficient, the more effective the anti-slip effect. Evaluation of foaming property of glove surface The glove was put on both hands, wetted with water, and the palms of the gloves were rubbed with both hands, and the foaming state at that time was observed. Evaluation of softness The lower the 100% modulus, the more flexible. Evaluation of Oil Resistance The smaller the percentage change in surface area, the higher the oil resistance.

[0023]

【table 1】 Comparative Example 1 shows the physical properties of a conventional NBR glove generally used as a household or work glove, and the tensile strength was 41%.
Although it is as tough as 0 kg / cm ² , it has a 100% modulus as hard as 28.0 kg / cm ² . On the other hand, Embodiments 1 to 6
Has the physical properties of a glove in which 20 parts by weight of an alkyl acrylate copolymer is blended with 100 parts by weight of an NBR latex. The difference is 3% (Embodiment 1), and no significant decrease is observed. 10
The 0% modulus is also up to about 32% compared to Comparative Example 1.
Is also a low value (Embodiment 5), and is flexible.
It can be seen from the dynamic friction coefficient that the anti-slip effect is improved.

In Comparative Example 2, 10 parts by weight of a plasticizer as a softening agent was added to NBR latex. The dynamic friction coefficient μK was 0.17, and the softening effect was obtained by adding the plasticizer. However, the anti-slip effect was rather adverse because the plasticizer bleeds to the surface of the film. Regarding foaming on the glove surface when the glove comes in contact with water, in the case of Comparative Example 2 using a plasticizer, foaming was frequently observed, which was inconvenient for practical use, but the alkyl acrylate copolymer was used as a softening agent. Embodiment 1 used
In Nos. 6 to 6, no foaming was observed. This indicates that the alkyl acrylate copolymer in the NBR glove composition of the present invention not only has an effect as a polymer compound having a flexible segment, but also chemically reacts with NBR via a vulcanizing agent and zinc oxide in a latex compound. This is considered to indicate that the compound has an effect as a polymer compound capable of binding to a molecule.

[0025]

As described above, according to the present invention, alkyl acrylate-acrylonitrile-
By blending an appropriate amount of acrylic acid or methacrylic acid copolymer latex, NBR gloves can be provided with sufficient oil resistance and toughness for home use or work use, and significantly improve flexibility and texture. Can be.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hidetoshi Kishihara 570-1 Kamata, Hirohata-ku, Himeji-shi, Hyogo 5-2 Mukogaoka H-Bus No. 1006 F-term (reference) 3B033 AC03 BA01

Claims (1)

[Claims] 1. A copolymer of 94 to 75 mol% of alkyl acrylate, 5 to 20 mol% of acrylonitrile, and 1 to 5 mol% of acrylic acid or methacrylic acid with respect to 100 parts by weight of solid content of NBR latex. Formed using NBR latex blended with NR as a material
R gloves.