JPH09111023A - Surface modification of rubber product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplish the surface modification of a condom as a rubber product so as to improve its use feeling by ensuring the presence of a lubricant film of sufficient thickness on its surface even in case frictional force is applied thereto, by incorporating a rubber with a specific polypeptide compound to provide a rubber surface of excellent humectancy. SOLUTION: This surface modification of a rubber product is accomplished by incorporating a rubber with a polypeptide compounds of the formula R- CONH-[amino acid]n -COO<-> M<+> (R is an 8-20C saturated or unsaturated hydrocarbon; M<+> is Na, K or an ethanolamine derivative; (n) is 3-20) in such an amount as to be pref. 1-5wt.%, on a genuine basis, relative to the amount of the rubber. The amino acids as constituents of the polypeptide compound pref. include at least one molecule of hydroxyproline as an amino acid of excellent humectancy. The ethanolamine derivative in the formula is e.g. monoethanolamine, diethanolamine and/or triethanolamine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface modification of a rubber product of a condom which is excellent in usability.

[0002]

2. Description of the Related Art Condoms currently used have a lubricant applied to the surface, but they are not satisfactory in terms of use. That is, silicone oil is most often used as a lubricant, but it is a hydrophobic oil that is not pleasant to the human skin, and if it adheres to your body or clothing, wash it with detergent etc. Is hard to fall off and is unpopular. Newly glycerin, ethylene glycol,
Homopolymers or copolymers of glucoside (meth) acrylate, methoxyoligoethylene glycol (meth) acrylate, (meth) acrylic amide, etc. in one or a mixture of two or more polyhydric alcohols such as dipropylene glycol and diethers, and multitose Hydrophilic lubricants containing carboxymethyl cellulose and gelatin have been proposed. However, these hydrophilic lubricants have poor affinity with the rubber surface forming the condom substrate, and when mechanical force such as friction is applied, the lubricant layer on the rubber surface becomes thin, and sometimes The rubber surface is in direct contact with the skin and does not function as a lubricant.

[0003]

In the present invention, when a condom is used and a friction force is applied, a stable lubricant film is present on the surface of the condom, and sufficient lubricity is exhibited. There is a feeling of use.

[0004]

[Means for Solving the Problems] Polypeptides firmly attached to the rubber surface of a condom substrate are arranged to make the rubber surface more moisturizing, and a hydrophilic lubricant is applied to the rubber surface. As a result, it is possible to manufacture a condom with a lubricant that is excellent in usability and does not contaminate the body or clothing.

In order to make the surface of the rubber more moisturizing, the compound represented by the general formula (1) of [claim 1] is blended with the rubber latex preparation liquid and applied to a mold of a predetermined shape or By forming a thin film of impregnated rubber, a hydrophilic surface mainly composed of a polypeptide having excellent friction resistance was formed on the rubber surface, thus completing the present invention. By applying a hydrophilic lubricant to this surface, the bond between the rubber surface and the lubricant is greatly improved, and even if a strong frictional force is applied during use, the condom surface will always have a sufficient thickness of lubricant. It was possible to obtain an excellent usability in the hall.

It is preferable that one or more molecules of hydroxyproline are present as an amino acid constituting the polypeptide, which is particularly excellent in moisturizing property, but other amino acids are not particularly limited. Regarding the molecular weight of the polypeptide, when the number of amino acids is 3 or less, sufficient moisturizing power and bond with the lubricant cannot be obtained, and
If it exceeds 0, the compatibility with the rubber latex decreases, the mechanical properties of the rubber substrate are impaired, and the binding force of the polypeptide compound with the rubber surface decreases, so that the expected effect cannot be obtained. .

The hydrophobic group constituting the polypeptide compound is preferably a saturated or unsaturated hydrocarbon having a carbon number of 8 to 20 as a hydrocarbon chain. When the carbon number was smaller than this, sufficient binding force could not be obtained between the polypeptide compound and the rubber surface. Further, when the carbon number was large, sufficient moisturizing properties could not be obtained.

The amount of the polypeptide compound added to the rubber latex is 1 based on the amount of rubber in terms of each pure component.
It is preferable to add between 5% and 5%, but it is not particularly limited as long as it does not impair other physical properties of the rubber substrate.

When adding the polypeptide compound to the rubber latex, it is necessary to change the addition of auxiliary materials such as a plasticizer, a cross-linking agent, an antioxidant, an antioxidant, and white carbon, which are usually added when making a condom. There is no.

As the ethanolamine compound used for neutralizing the amino acid compound, any one of monoethanolamine, diethanolamine and triethanolamine can be used or a combination of two or more thereof can be used.

[0011]

[Function] A hydrophobic group forming a polypeptide compound forms an intermolecular compatibilization with a rubber base material and strongly binds to it, and an amino acid and a salt thereof forming a popeptide compound are arranged on the rubber surface to form a bond with a lubricant. This is probably due to the formation of a good intermolecular compatibility.

[0012]

EXAMPLES The contents of the present invention will be described in detail with reference to Examples and Comparative Examples.

[0013]

[Results] A condom base material was prepared by adding a polypeptide compound having the content shown in the above-mentioned examples and control examples to the prepared rubber latex, and a condom coated with a water-soluble lubricant was prepared. Created. In addition, a condom made of only the above latex was also coated with the same lubricant as above, and this was designated as Target Example III.
Five monitors were selected for these condoms and a practical test was conducted. The results are shown in Table 1.

[0014]

EFFECT OF THE INVENTION Even when a strong mechanical force is applied, it is possible to obtain a condom having a high commercial value and having an excellent feeling of use.

Claims (2)

[Claims] 1. A method for modifying the surface of a rubber product obtained by compounding a compound having a molecular formula represented by the following general formula (1) with rubber: R-CONH- [amino acid] n-COO ^- M ⁺ (1) Formula R: Saturated or unsaturated hydrocarbon having 8 to 20 carbon atoms M ⁺ : Na, K, or ethanolamine derivative n: 3 to 20 2. A method for modifying the surface of a rubber product according to claim 1, wherein one of the amino acids of the formula (1) is hydroxyproline.