JPH0872170A - Hollow elastic molded article and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Objective] In contrast to the drawbacks of the prior art, the present invention has excellent wearing feeling and operability, but the film is not easily broken, and the base end portion is easily gripped when detaching and attaching, An object of the present invention is to obtain a hollow elastic molded product that is not easily torn or torn, especially a medical rubber glove. [Structure] A hollow elastic molded product in which a tip end portion and a side end portion are closed and a base end portion (hem portion) is opened,
The thickness of the coating at the tip portion is thinner than the coating thickness at the base end portion (hem portion), and the portion where the coating is rolled up (beading) along the opening circumference of the base end portion (hem portion) ( Hereinafter, an elastic molded article having a beading portion), a method for producing the hollow elastic molded article, and a medical rubber glove in which the hollow elastic molded article has a glove shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow elastic molded product which is easy to wear and easy to operate and is hard to break, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Body-fitting rubber products such as surgical gloves and condoms have two contradictory problems. One of them is a feeling of wearing, and it is required that it fits to the body and gives a feeling as if the user does not wear the product, and that there is no feeling of pressure even when used for a long time. Another issue is the prevention of contamination (property), which requires a strong film that does not pass viruses and bacteria, and that does not tear or break. Conventionally, in order to solve this contradictory problem, the compounding of rubber, the thickness of the film, and the like have been studied, but the effect is not always sufficient. Conventional surgical gloves have a relatively thick film on the fingers, so the feeling of wearing the fingers
The operability was poor, and the coating on the hem on the wrist side was relatively thin, so the hem was liable to tear. In addition, there were gloves with thin fingers and a relatively thick hem.However, these gloves do not have beading for reinforcement, so they are difficult to grip when wearing / removing, and they tend to tear easily. there were.

[0003]

In contrast to the above-mentioned drawbacks of the prior art, the present invention is excellent in wearing feeling and operability, but the film is not easily torn, and the base end portion is easy to grip when detaching and attaching. An object of the present invention is to obtain a hollow elastic molded product that is resistant to tearing or tearing of a part, particularly a medical rubber glove.

[0004]

According to the present invention, in a hollow elastic molded product in which a tip end portion and a side end portion are closed and a base end portion (hem portion) is opened, the thickness of the coating film at the tip end portion is A portion that is thinner than the thickness of the base end portion (hem portion) and is wound up (beaded) along the opening circumference of the base end portion (hem portion) (hereinafter referred to as the beading portion). By providing the above, the above-mentioned problems of the prior art are solved. The present invention, in the coagulant bath and latex bath, focusing on the amount of coagulant and latex adhered to the mold, depending on the mold lifting speed,
The ratio of the thickness of the film at the tip portion / the thickness of the film at the base end portion (hem portion) satisfying the above requirements manufactured using the above knowledge (hereinafter referred to as the film balance ratio) is less than 1, 0. 5
The present invention relates to the above hollow elastic molded product, particularly a medical rubber glove and a method for producing the same. The hollow elastic molded article of the present invention,
In a method of producing a hollow elastic molded article by preliminarily immersing in a coagulant and drying the mold with the coagulant attached to the surface, and immersing the mold in a natural rubber latex and / or an elastomer latex bath, It can be produced by pulling up the mold base end portion (skirt portion) in at least one of the coagulant bath and the latex bath faster than the tip end portion. In particular, it is advantageous to pull up the mold base end portion (hem portion) in both the coagulant bath and the latex bath faster than the tip end portion. Hereinafter, the hollow elastic molded article of the present invention and the method for producing the same will be specifically described below by taking a rubber glove, particularly a medical rubber glove, as an example. The hand form of a medical rubber glove as a mold was dipped in a bath of a coagulant with the fingers down, to form a film of the coagulant on the surface of the hand form, preferably a film having a uniform film thickness. The dipping speed of the handprint in the coagulant bath is not particularly limited, but if it is too fast, air is entrained in the handprint, and if too slow, it becomes difficult to control the thickness of the coating, or the production line Since it is not preferable because the length becomes longer, it is usually 1200 mm / min or more and 2200 mm / min.
The bill is dipped to a predetermined position at a speed of min or less.
The bill was soaked in the coagulant bath for a predetermined time and then pulled out of the coagulant bath. Also, the lifting of the hand mold is usually 120 to 150.
It is performed at a speed of 0 mm / min, but as described above, the pulling speed of the hand mold immersed in the coagulant bath is slowed by the finger portion,
It is preferable to perform it so that it is faster at the hem portion, for example, the pulling speed of the finger portion is 300 mm / min,
The lifting speed of the hem portion is changed such that it is 1200 mm / min.

As the coagulant that constitutes the coagulant bath,
For example, at least one compound selected from the group consisting of organic acids such as formic acid and acetic acid, calcium nitrate, calcium chloride, calcium acetate, polyvalent metal salts such as zinc acetate, and amine salts of specific organic acids, generally, N
Calcium nitrate is used as the main component for R and IR latexes, and calcium chloride or a combination of calcium chloride and calcium nitrate is suitable for latexes such as CR, NBR, and SBR. The coagulant is generally dissolved in water and / or alcohol (mostly methyl alcohol) as a solvent and used as a solution having a concentration of 2 to 20%. In particular, in order to obtain a film balance ratio and film thickness suitable for medical rubber gloves, the coagulant concentration is preferably 10 to 20%.

The latex bath used in the present invention is composed of natural rubber latex (NR) and / or elastomer latex. Examples of the elastomer include isoprene rubber (IR) and styrene-butadiene rubber (S
BR), acrylonitrile-butadiene rubber (NB
R), chloroprene rubber (CR), methyl methacrylate-butadiene rubber (MBR), or a mixture of these elastomers and natural rubber. Further, as the raw material latex, in particular, when the hollow elastic molded article of the present invention is a glove, it is preferable to add a softening agent to the raw material latex in order to reduce the feeling of tightening the fingertip. Examples of such a softening agent include polyisoprene spindle oil, liquid paraffin, solid paraffin, paraffin-based process oil, aromatic process oil, and naphthene-based process oil. Further, the latex bath may contain various rubber compounding agents such as vulcanization accelerators and antioxidants. The concentration of the latex bath is preferably such that the total solid content (TCS) is in the range of 30 to 60%, more preferably 40 to 55%. The bath temperature is usually about 20 to 40 ° C. In order to facilitate the formation of the beading portion, it is preferable that the hem portion is a thin film as compared with other portions, so that the handprint is equivalent to the beading portion after being immersed in a latex bath with the finger portion facing down. The hem portion of the hand shape, for example, 2 to 3 cm of the hem portion of the hand shape, is pulled up within 5 seconds, preferably immediately after being immersed in the latex bath. part)
It can be made thinner than that of the latex film. The rate of immersion in the latex bath is not particularly limited, but if it is too fast, air is entrained in the bill, and if it is too slow, it becomes difficult to control the thickness of the coating, or the manufacturing line becomes long, which is preferable. No, so usually 12
It is preferable to immerse the handprint to a predetermined position at a speed of 00 mm / min or more and 2200 mm / min or less. The residence time in the latex bath is not particularly limited, but in order to eliminate the influence of the difference in residence time between the mold tip part and the base end part (hem part) (to eliminate the non-uniformity of latex adhesion)
For this reason, a residence time of at least about 30 seconds is preferable. The hand mold is also lifted from the latex bath at a speed of 120 to 1500 mm / min as in the case of the coagulant bath, but it is preferable that the finger part is slow and the hem part is fast. For example, the lifting speed of the finger part 3
00mm / min, 1200mm pulling speed of hem
The speed is changed as shown in / min. Therefore, it is preferable that the hand molds of both the coagulant bath and the latex bath are pulled up slowly at the finger portion and at the hem portion. For example, the pulling rate from the coagulant bath and the pulling rate from the latex bath are both 300
mm / min, and 1200 mm / min at the hem portion, it is possible to produce a medical rubber glove having excellent properties with a film balance ratio represented by finger thickness / hem thickness of about 0.8. it can.

After the handprint with the latex adhered as obtained above is dried to the extent that a beading portion can be formed, a conventional beading portion forming method, for example, the beading portion is formed as follows. can do. A hollow elastic molded article made of latex is mechanically rolled up from the base end open end of the bill to form a beading portion. In particular, in the hollow elastic molded product of the present invention, the thickness of the latex film of the beading portion of the hand mold is compared with the thickness of the latex film of the base end portion (hem portion) other than the beading portion as described above. Since it is formed thin, the beading portion can be easily formed. Next, after drying the glove-shaped molded product formed on the hand mold so that the physical properties that can be removed are obtained, the film is removed from the hand mold while it is excellent in wearing feeling and operability, but the film is hard to tear, and when detaching Moreover, it was possible to obtain a rubber glove which is easy to grip the base end portion and is unlikely to tear or tear at the base end portion. Further, since the water absorption rate of the rubber gloves can be reduced by subjecting the rubber gloves made of latex to the extraction treatment with water, the extraction treatment may be performed as necessary. Incidentally, various hollow elastic molded articles of the present invention, a method using an internal coagulant in addition to the method using an external coagulant as described above, that is, after immersing the mold in a bath,
It may also be produced by a method of gelling the latex by immersing it in a coagulant bath.

Examples of the hollow elastic molded article of the present invention obtained as described above include medical gloves such as surgical gloves and surgical gloves, condoms and the like. When the hollow elastic molded product of the present invention is a medical glove, the finger part of the glove is measured at three points in the vicinity of the finger end node and at a point equally dividing an annular line of 25 mm from the end of the hem part. When the ratio of the thickness / the thickness of the skirt is obtained and used as an index of the film balance, the film balance ratio is less than 1 and 0.5 or more, preferably 0.9.
It is 5 or less, more preferably less than 0.9. Moreover, since the operability and the tactile sensation during the operation are excellent and the feeling of wearing such as no pressure feeling is good, the average thickness of the film on the finger portion is 2
Less than 20 μm, more than 130 μm, especially 180-220
It is preferably μm. Further, the average thickness of the coating film at the hem portion is preferably 220 μm or more, and particularly preferably 220 to 260 μm, for the reason of preventing contamination due to tearing and tearing of the film and reducing deviation or blistering of the hem portion.
Rubber gloves having the above-mentioned film balance ratio, the average film thickness of the finger portion, and the average film thickness of the hem portion,
In particular, rubber gloves made from latex containing a softening agent such as polyisoprene as described above have excellent flexibility, so there is particularly little feeling of tightening at the fingertips, and there is very little damage to the hem during wearing, so it is used as a medical glove. It's very good.

Next, specific embodiments of the present invention will be described. 1. In a hollow elastic molded product in which the tip and side edges are closed and the base (hem) is open, the thickness of the coating on the tip is thinner than the thickness of the coating on the base (hem). A hollow elastic molded article, characterized in that it has a portion (hereinafter referred to as a beading portion) in which the film is rolled up (beading) along the circumference of the opening of the base end portion (hem portion). 2. In the above-mentioned 1 hollow elastic molded product, the elastic molded product is characterized in that the film thickness of the beading portion is thinner than the film thickness of the base end portion (hem portion) other than the beading portion. . 3. In the hollow elastic molded product of 1 or 2, the shape is glove-like, and the average thickness of the film of the finger portion that is the tip portion is less than 220 μm, 130 μm or more, and the base end portion (hem portion). A medical rubber glove characterized in that the average thickness of the film on the wrist portion (excluding the beading portion) is 220 μm or more. 4. The medical rubber glove according to the above 3, wherein the base end portion (hem portion) has an average thickness of 220 μm or more and 260 μm or less. 5. The hollow elastic molded article according to 1, 2, 3 or 4, wherein the shape is glove-like and the film is represented by the thickness of the film on the finger portion / the thickness of the film on the base end portion (hem portion). A medical glove having a balance ratio of less than 1 and 0.5 or more. 6. A method for producing a hollow elastic molded article by immersing a mold in a coagulant bath and a natural rubber latex and / or an elastomer latex for a predetermined time, which comprises a mold base in at least one of the coagulant bath and the latex bath. The pulling up of the end portion (hem portion) is performed faster than the pulling up of the tip portion.
A method for producing the hollow elastic molded article according to 4 or 5. 7. In the method for producing a hollow elastic molded article as described in 6 above, pulling up of the mold base end portion (skirt portion) in both the coagulant bath and the latex bath is performed faster than the tip end portion. A method for producing a hollow elastic molded product. 8. In the method for producing a hollow elastic molded product according to 6 or 7, the mold is pulled up in the coagulant bath and the latex bath at a speed of 120 to 1500 mm / min and the base end portion (hem portion) of the mold is pulled up. A method for producing a hollow elastic molded article, characterized in that the step is carried out faster than the pulling up of the tip portion. 9. The method for producing a hollow elastic molded article according to 6, 7 or 8 above, wherein dipping of the mold into at least one of a coagulant bath and a latex bath is performed up to a predetermined position.
A method for producing a hollow elastic molded product, characterized in that the process is carried out at a speed of 00 mm / min or more. 10. In the method for producing the hollow elastic molded article of 6, 7, 8 or 9, the dipping of the mold into at least one of the coagulant bath and the latex bath is performed at a predetermined position of 1200 mm / min or more, A method for producing a hollow elastic molded article, which is performed at a speed of 2200 mm / min or less. 11. In the method 10 for producing a hollow elastic molded article, the mold is immersed in both a coagulant bath and a latex bath at a predetermined position of 1200 mm / min or more,
A method for producing a hollow elastic molded article, which is performed at a speed of 2200 mm / min or less. 12. In the method for producing the hollow elastic molded article of 6, 7, 8, 9, 10 or 11, the coagulant concentration in the coagulant bath is in the range of 2 to 20%, preferably 10 to 20%. A method for producing a hollow elastic molded product characterized. 13. In the method for producing the hollow elastic molded article of 6, 7, 8, 9, 10, 11 or 12, the latex bath has a total solid content (TCS) of 30 to 60%, preferably 40 to 55%. The method for producing a hollow elastic molded article characterized in that

[0010]

【Example】

Examples 1 to 3 are composed of the following compositions, and have a concentration of 15 to 20% and a temperature of 20 to 3.
A surgical rubber glove hand mold preheated to a temperature of 55 to 65 ° C was vertically immersed in a coagulant bath at 0 ° C. The hand-type dipping angle is a vertical angle in this embodiment, but an arbitrary dipping angle can be used in the present invention.
The entire hand mold was immersed within 15 seconds. Coagulant composition Methanol 78.18 to 73.50% Calcium nitrate 15.00 to 20.00% Water 5.40 to 5.08% Surfactant 1.42% After immersing the hand mold to a predetermined position, it is suspended. And immediately started pulling up. As shown in Examples 1, 2 and 3 in Table 1, the pulling speed was changed in the coagulant bath so that the skirt portion had a large pulling speed and the finger portion had a small shifting speed. In addition, as a comparative example, the coagulant bath was pulled up without changing the speeds of the fingers and the hem (Comparative Example 1). After the hand mold was lifted from the coagulant bath in a suspended state, the hand mold was swung up at an angle of 90 °, that is, laterally, rotated and moved, and then the coagulant was dried in a drying oven to stop the fluidity of the coagulant. The hand mold, which had been subjected to the immersion treatment in the coagulant bath, had a total solid content (TSC) of 43 to 49% and a temperature of 20.
Immersion in a latex bath at -30 ° C within 15 seconds.
To make the thickness of the film on the beading part thinner than the thickness of the film on the base end (hem part) other than the beading part, the hand hem part corresponding to the beading part after dipping the handprint Only 2-3 cm was immediately withdrawn from the latex bath. Then, the remaining hand mold part is put in the latex bath for 30
After staying for a second, the pulling speed was increased at the hem without changing the pulling speed at the hem and the finger (Example 1).
Also, the finger was used to perform a small gear shift to pull up (Examples 2 and 3). Further, for comparison, pulling was performed without changing the speeds of the fingers and the hem (Comparative Example 1). Then, the latex was dried in a latex drying oven to dry the latex. The drying may be carried out in such a dry state that the fluidity of the latex is stopped and the latex can be set. Further, the dry hand mold was subjected to extraction treatment with water in an extraction water bath at 90 to 100 ° C. for 60 seconds to reduce the water absorption of the obtained rubber gloves. The hand mold that had been subjected to the water extraction treatment was dried in an extraction water drying furnace to such an extent that a beading could be formed, and then a beading was formed by a conventional means. Next, in order to obtain demoldable physical properties,
After drying at 0 to 100 ° C for 14 minutes, demolding and vulcanization were performed. The film thickness and film balance of the gloves produced in each of the above Examples and Comparative Examples were measured, and the measurement results are shown in Table 1.
The film thickness was measured as follows. (Measurement of film thickness) The glove's fingertip joints are each divided into 3 points, and 8 points from the hem end of the arm are divided into equal parts on an annular line of 25 mm, and the finger thickness / hem thickness is measured. It was determined and used as an index of film balance. In the results of Table 1, it was possible to adjust the film balance ratio with the thickest hem portion and the thinnest finger portion most effectively in the coagulant bath and the latex bath at a pulling rate of 1200 mm / min at the hem portion and at the finger portion. 300m
The speed was changed to m / min, and the film balance ratio was about 0.8.

Example 4 Coagulant bath with 16 and 20% concentration (containing calcium nitrate)
After immersing the hand mold for 15 seconds, the hand mold was lifted from the coagulant by changing the lifting speed to 1200 mm / min at the hem portion and 300 mm / min at the finger portion. Then, the hand mold is subjected to a total solid content (TSC = 39.2, 43.7,
(48.7%) different latexes were retained for 30 seconds, and then the lifting speed was changed to 1200 mm / min at the hem portion and 300 mm / min at the finger portion, and the hand mold was pulled up from the latex bath. The thickness of the film of the rubber glove produced as described above was measured, and the results are shown in Table 2 and FIG. From the results shown in Table 2 and FIG. 1, the thickness of the coating becomes large by increasing the solid content and the coagulant concentration. However, the thickness of the finger portion is always smaller than the thickness of the hem portion, and the thickness of the finger portion and the thickness of the hem portion are not reversed.

Example 5 After immersing the hand mold in a coagulant having a concentration of 15 to 20%, the speed of pulling up is slower at the finger part and faster at the hem part so that the speed is 1200 mm / min to 300 mm / mi near the wrist.
After changing to n and pulling up the hand die, the hand die angle was swung up to 90 °, that is, in the lateral direction. Next, the hand mold is put into a latex having a predetermined total solid content (TSC = 43 to 49%).
It was dipped at 0 mm / min and allowed to stay for 30 seconds. 2 to 3 cm from the base end of the hem has a thin film portion for winding up the film, so immediately after dipping to a predetermined position, 2
The thin film portion was prepared by pulling up by ~ 3 cm. After soaking in the latex bath, when pulling up the hand mold from the latex bath, the pulling speed is slow at the tip of the hand mold and fast at the base end of the hand mold. The speed is 1200 mm / min near the wrist.
Was changed to 300 mm / min, the whole hand mold was pulled up, and then the hand mold angle was swung up to 90 °. The rubber gloves manufactured as described above were measured for film thickness, film balance, tensile test (tensile strength, tensile elongation) and the like. The results are shown in FIGS. 2 to 4 and Tables 3 to 5. The physical properties of the comparative examples and the examples are measured according to JIS T910.
The tensile strength and elongation were measured according to 7. At this time, the median film thickness was used for the calculation of the cross-sectional area. The tensile strength and elongation at the time of swelling were measured immediately after the JIS No. 3 test piece was immersed in physiological saline for 2 or 8 hours. Incidentally, the film thickness, film balance ratio in each of the comparative examples and Examples,
The values of tensile strength and tensile elongation (%) are average values of three or more samples.

[0013]

[Table 1]

[0014]

[Table 2]

[0015]

[Table 3]

[0016]

[Table 4]

[0017]

[Table 5]

[0018]

【The invention's effect】

1. According to the method for producing a hollow elastic molded article of the present invention,
By adjusting the speed of pulling up the mold from the coagulant bath and / or the latex bath so that it is short at the tip of the mold and long at the base of the mold, a difference occurs in the amount of resin liquid deposited on the mold, A hollow elastic molded product having a film balance ratio of less than 1 can be easily manufactured. 2. The hollow elastic molded article of the present invention obtained in 1 above, especially the medical rubber glove, has excellent wearing feeling and operability because the tip portion is thin, but is broken because the base end side has a thicker film than the tip end. -It has improved tearing. Further, since the hollow elastic molded product according to the present invention is provided with beading around the opening on the base end side, it is easy to grasp the base end part (hem part) at the time of mounting and demounting this product, and there is no beading. Compared to, the base end is less likely to tear or tear.

[Brief description of drawings]

FIG. 1 is a diagram showing the influence of latex solid content and coagulant concentration on the thickness of a molded film.

FIG. 2 is a diagram showing the film thickness and film balance of the molded gloves of the present invention product and the conventional product.

FIG. 3 is a diagram showing the tensile strength of the molded gloves of the present invention product and the conventional product.

FIG. 4 is a diagram showing the tensile elongation of molded gloves of the present invention product and the conventional product.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minor Ono Minoru No. 12-17 Kako-cho, Naka-ku, Hiroshima City, Hiroshima Prefecture JMS Inc. (72) Inventor Sakae Ogata Kako-cho, Naka-ku, Hiroshima City, Hiroshima Prefecture No. 12-17 No. 17 in JMS Inc.

Claims (10)

[Claims] 1. A hollow elastic molded product in which a tip end portion and a side end portion are closed and a base end portion (hem portion) is open, and a thickness of a coating on the tip end portion is equal to that of a base end portion (hem portion). Elastic molding, which is thinner than the thickness of the coating and has a portion (hereinafter referred to as a beading portion) in which the coating is wound up (beading) along the opening circumference of the base end portion (hem portion). Goods. 2. The hollow elastic molded article according to claim 1, wherein the film thickness of the beading portion is smaller than the film thickness of the base end portion (hem portion) other than the beading portion. An elastic molded product characterized by. 3. The hollow elastic molded article according to claim 1 or 2, wherein the shape is glove-like, and the average thickness of the film of the finger portion which is the tip portion is less than 220 μm, 13
0 μm or more, and the average thickness (excluding the beading part) of the film on the wrist part which is the base end part (hem part) is 22.
An elastic molded product characterized by having a thickness of 0 μm or more. 4. The hollow elastic molded article according to claim 1, 2 or 3, wherein the shape is glove-like and the thickness of the film on the finger part / the thickness of the film on the base end part (hem part) is A medical rubber glove having a coating film balance ratio of less than 1 and 0.5 or more. 5. A coagulant bath and natural rubber latex and / or
Alternatively, in a method for producing a hollow elastic molded article by immersing a mold in an elastomer latex for a predetermined time, pulling up a mold base end part (hem part) in at least one of a coagulant bath and a latex bath. The method for producing a hollow elastic molded article according to claim 1, 2, 3 or 4, wherein the step is carried out faster than the pulling up of the tip portion. 6. The method for producing a hollow elastic molded article according to claim 5, wherein the raising of the mold base end portion (hem portion) in both the coagulant bath and the latex bath is performed by raising the tip end portion. A method for producing a hollow elastic molded product, which is characterized by being carried out at high speed. 7. The method for producing a hollow elastic molded article according to claim 5 or 6, wherein the mold is immersed in at least one of a coagulant bath and a latex bath.
A method for producing a hollow elastic molded product, characterized in that the process is carried out at a speed of 00 mm / min or more. 8. The method for producing a hollow elastic molded article according to claim 7, wherein the immersion of the mold in a coagulant bath and a latex bath is 1200 mm / min or more and 2200 mm / mi.
A method for producing a hollow elastic molded article, which is performed at a speed of n or less. 9. The method for producing a hollow elastic molded article according to claim 7 or 8, wherein the immersion of the mold in both the coagulant bath and the latex bath is 1200 mm / min or more and 2200 mm / min or less. A method for producing a hollow elastic molded article, which is performed at a speed. 10. The method for producing a hollow elastic molded article according to claim 5, 6, 7, 8 or 9, wherein only the mold portion corresponding to the beading portion is pulled up from the latex bath within 5 seconds. A method for producing a hollow elastic molded product characterized.