JP3045512B2 - Antimicrobial polyurethane foam, antimicrobial polyurethane elastomer and antimicrobial polyurethane coating composition - Google Patents

Description

The present invention relates to an antibacterial polyurethane foam, an antibacterial polyurethane elastomer, and an antibacterial polyurethane coating composition, in which scorch-like discoloration is suppressed, particularly an antibacterial agent which is effective against Staphylococcus aureus. The present invention relates to a polyurethane foam and the like.

The present invention provides a kitchen cleaner, a mask, a body sponge, a cosmetic puff, a filter element, a sealing material,
Used for underwear pads, seat cushions, mattresses, headrests, dishwasher pads, agricultural foam, inner wall materials, paper diapers, shoe soles (insoles), ski wear, and the like.

[Conventional technology]

Conventionally, as an antibacterial polyurethane foam, a flexible polyurethane foam in which an inorganic antibacterial agent such as a metal ion (particularly, a zeolite-supported antibacterial agent in which a metal ion is supported on zeolite) is known (JP-A-Heisei Heisei). 1
-161033).

[Problems to be solved by the invention]

In the conventional polyurethane foam, since a predetermined metal ion is used, scorch-like discoloration which is presumed to be caused by the catalytic action of the ion is induced. Also,
Although this form is antibacterial against E. coli,
Not showing antibacterial effect against Staphylococcus aureus,
It has been recognized so far.

As described above, a polyurethane foam which suppresses the discoloration and exhibits an antibacterial action against Staphylococcus aureus is desired. Since Staphylococcus aureus causes food poisoning, a polyurethane foam that can be used with particular ease as a kitchen cleaner has been desired. In addition, about polyurethane elastomer and polyurethane coating composition,
There is also a desire.

The present invention has been made in consideration of the above-mentioned problems while solving the above-mentioned problems, and suppresses discoloration. The present invention also provides a polyurethane foam, a polyurethane elastomer, and a polyurethane coating composition which exhibit antibacterial activity against Staphylococcus aureus. The purpose is to provide.

[Means for solving the problem]

The present inventors have conducted intensive studies on antibacterial substances that are effective in suppressing scorch-like discoloration and effective against Staphylococcus aureus. As a result, they have found that chitosan has this effect and completed the present invention.

That is, the antibacterial polyurethane foam of the first invention is:
A polyol, a catalyst, a foaming agent and a chitosan antibacterial agent are mixed, and thereafter, an antibacterial polyurethane foam produced by adding an organic isocyanate to the mixture, wherein chitosan is dispersed and contained in the polyurethane foam. Features. The anti-shape polyurethane elastomer of the fourth invention is characterized in that chitosan is dispersed and contained in the polyurethane elastomer.

In the antibacterial polyurethane foam of the second invention or the antibacterial polyurethane elastomer of the fifth invention, when the total amount of the polyol, the organic isocyanate and the chitosan is 100 parts by weight, the content of the chitosan is 1 to 12 parts by weight. (Hereinafter simply referred to as%).

The antibacterial polyurethane coating composition of the sixth invention is characterized by containing a coating base containing a polyol and an organic isocyanate and chitosan. Also in the antibacterial polyurethane coating composition of the seventh invention, the content of the chitosan is 1 to 12% as described above.

The chitosan is a product obtained by deacetylating chitin by heating an alkali solution with an alkali solution or by performing an alkali melting.
Poly-D-glucosamine. This chitosan does not show scorch-like discoloration, is excellent in safety for human body, and is also excellent in antibacterial property, particularly excellent effect on Staphylococcus aureus as shown in the following examples.

The content of chitosan is preferably 1 to 12% based on the total amount of the polyol, organic isocyanate and chitosan as in the second, fifth and seventh inventions. If the content is less than 1%, the antibacterial effect by addition of chitosan is small, and if it exceeds 12%, the effect is saturated, and the performance of the polyurethane structure such as foam or the coating film is deteriorated. .

As the polyol, organic isocyanate, and foaming agent used as the raw material of the polyurethane foam, various kinds are generally selected and used in accordance with the physical properties, applications, and the like of each polyurethane structure (product). The amount of each compound, the purpose,
It is selected depending on the application and the like, and is generally set to a usual amount.

As the polyol, a polyether polyol, a polyester polyol, or a modified polyol thereof (for example, a polyether ester polyol or the like) can also be used. A mixture of two or more of these can also be used.

As the polyether polyol, an epoxide adduct is generally used, and (1) an alkylene oxide (eg, ethylene oxide) adduct of a polyhydric alcohol such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, or sucrose; 2) alkylene oxide adducts such as diethanolamine, triethanolamine and ethylenediamine;
(3) Modified polyols such as graft-type polymer polyols such as styrene and acrylonitrile are exemplified.

As the polyester polyol, (1) malonic acid,
Aliphatic carboxylic acids such as succinic acid and adipic acid, or aromatic carboxylic acids such as phthalic acid and terephthalic acid, or mixtures thereof, and aliphatic glycols such as ethylene glycol, dipropylene glycol, butylene glycol, propylene glycol, and diethylene glycol, and triglycerides. Examples thereof include polyester polyols having a hydroxyl group at a terminal obtained by polymerization from triols such as methylolpropane and glycerin, and (2) polyester polyols such as polycaprolactone obtained by ring-opening polymerization of ε-caprolactone.

The molecular weight of the polyol is preferably from 600 to 6,000 in the case of a flexible or semi-rigid polyurethane foam, and particularly preferably from 1,000 to 5,000. This is less than 600 or 6000
This is because if the ratio exceeds the above, physical properties and reactivity are significantly reduced. In the case of a rigid polyurethane foam, the molecular weight is usually 300 to 600.

The organic isocyanate is an organic compound containing two or more isocyanate groups in the same molecule, and includes aliphatic and aromatic isocyanates, polyisocyanate monomers, mixtures thereof, and modified products thereof. Examples of the aliphatic isocyanate include hexamethylene diisocyanate, isophorone diisocyanate, and methylcyclohexane diisocyanate. As the aromatic isocyanate, tolylene diisocyanate (2, 4, and / or
Or 2,6 isomers), diphenylmethane diisocyanate, polyfunctional isocyanates and the like. As metamorphosis,
Examples of the prepolymer include a modified urethane, a modified allophanate, and a modified isocyanurate.

As the catalyst, one or more of an organic amine and a tin compound can be used. As this organic amine,
(1) monoamine such as triethylamine, (2) cyclic amine such as N-methylmorpholine, (3) diamine such as triethylenediamine, tetramethyl-1,4-butanediamine, (4) etheramine such as dimethylethanolamine, (5) Other triamines, hexamines, cyclic polyamines and the like can be used. As the tin compound, (1) a tetravalent tin compound such as dibutyltin dilaurate and dibutyltin diacetate, and (2) a divalent tin compound such as stannas octate and stannas oleate can be used.

As the blowing agent, water (which generates carbon dioxide gas by reaction with an organic isocyanate) is usually used. If necessary, low boiling organic compounds such as trichloromonofluoromethane and methylene chloride, air, A gas such as carbon dioxide can also be used.

Further, unless deviating from the effects of the present invention, it is possible to blend a foam stabilizer such as a polyether siloxane type, a flame retardant such as a halogenated phosphate, an antioxidant, a plasticizer, a filler or a coloring agent. it can.

As the polyurethane foam, a soft foam is usually used, but is not limited thereto, and may be a semi-rigid or hard foam.

In addition, as a method for producing these foams, a conventionally known method can be appropriately used, and for example, a discontinuous method, a continuous method, a one-shot method in a reaction step of a main raw material, a prepolymer method, or the like does not matter. .

In addition, the chitosan antibacterial agent used for the raw material of the polyurethane foam is the chitosan (β-poly-D
-Glucosamine) having a plurality of -OH and primary -NH groups in the molecule. Therefore, polyols, catalysts,
In the polyurethane foam of the first invention produced by addition polymerization and foaming of a mixture comprising a foaming agent, a chitosan antibacterial agent and an organic isocyanate, chitosan is directly incorporated in the main chain of the polyurethane constituting the foam.

The polyurethane elastomer is also manufactured by a known method by selectively using each of the above-mentioned raw materials, and may be of a foaming type or a non-foaming type. Since this requires elasticity,
A bifunctional or nearly bifunctional isocyanate material is used.

The paint base used as the paint composition is selected and used for each of the above-mentioned raw materials according to the desired physical properties, applications, and the like. Regardless of whether it is a one-pack type or a two-pack type, the raw materials, catalysts and the like to be used differ depending on the type. For example, one using two liquids of an organic isocyanate composed of a prepolymer having free isocyanate and a polyol prepolymer, a one-liquid type using an organic isocyanate protected by blocking a triisocyanate group with phenol, and immediately before use There is also one that cures by adding a catalyst. In addition, if necessary, other resins, various additives, and the like can be blended.

〔Example〕

 Hereinafter, the present invention will be described specifically with reference to examples.

This example relates to an antibacterial flexible polyurethane foam.

The foams (Examples 1 to 4 and Comparative Example 1) were produced by a usual method according to the formulation shown in Table 1.

That is, this flexible polyurethane foam is prepared by mixing a predetermined triol, a chitosan antibacterial agent, an amine catalyst, a silicone foam stabilizer, and water as a foaming agent with stirring and mixing with Stanas (II).
It was produced by adding octate, further adding a predetermined amount of tolylene diisocyanate, and stirring.

As the triol, a polyether polyol having a molecular weight of 3,000 (polymerized by adding propylene oxide to glycerin) was used. In tolylene diisocyanate, the isomer ratio (weight ratio) of 2,4- / 2,6- is 80/20.
It is. "DABCO" (manufactured by Sankyo Air Products) was used as the amine catalyst (triethylenediamine). As the foam stabilizer, a silicone foam stabilizer "L-520" (manufactured by Nippon Unicar Co., Ltd.) was used. As chitosan, "Chitosan S" (manufactured by Taiyo Chemical Co., Ltd., particle size: 10 to 200 μm)
m)) was used.

Next, the antibacterial activity of the obtained polyurethane foam was examined by the following method, and the results are shown in Table 2. This antibacterial activity test method complies with the Shake Flask Method of the Standard for the Antibacterial and Deodorized Products of the Textile Sanitation Processing Council.

That is, 70 ml of a meat extract broth medium (20-fold dilution) is added to 20
Place in a 0 ml volume triangular corvette, inoculate about 100,000 Staphylococcus aureus (test strain: "IFO 12732") per 1 ml, shake at 37 ° C, and count the number of bacteria over time. Measure. The numerical values in Table 2 show the number of bacteria per 1 ml of the shaking solution.
The specimen was cut into a size of 2 × 2 × 5 cm, and one side was finely cut into about 5 mm and used as a small lump. Similarly, Escherichia coli (test strain; "IFO 12734")
Was also measured.

As shown in Table 2, Example 1 (chitosan content; 6.2
%) Showed better antibacterial activity against both Escherichia coli and Staphylococcus aureus as compared to the case of Comparative Example 1 in which no chitosan was added.

In particular, Staphylococcus aureus is remarkably excellent.
That is, the antibacterial property after 6 hours is 700 times smaller than that of Comparative Example 1. In addition, Example 3 (11.6%) and Example 4 (14.1%) also have excellent antibacterial effects. Even when the chitosan addition amount of Example 2 was as small as 1.3%, a sufficient effect was recognized. Can be In addition, in Example 4 (1
4.1%), this effect tends to saturate.

In consideration of the above results and the physical properties of the polyurethane structure or the coating film, the amount of chitosan added is preferably 1 to 12%.

It should be noted that the present invention is not limited to the specific embodiments described above, but may be variously modified within the scope of the present invention in accordance with the purpose and application. That is, in the above examples, a flexible polyurethane foam was tested, but semi-rigid or rigid polyurethane foam, further a polyurethane elastomer, and a coating film formed using a coating composition, similarly dispersed chitosan uniformly, It is clear that similar or similar effects can be obtained by blending.

In addition, since chitosan exhibits excellent antibacterial properties as described above, it can be contained not only in the polyurethane-based structure or the coating composition, but also in other resins (especially foamed resins and the like for the same purpose), rubber, and coating. A similar effect can be obtained by incorporating the compound into a base or the like.

〔The invention's effect〕

In the antibacterial polyurethane foam and the like of the present invention,
Since chitosan is used without using an inorganic antibacterial agent unlike the conventional one, it does not induce scorch-like discoloration.

In addition, this chitosan is a natural product derivative, and as shown in the following safety data, is highly safe for the human body, etc., so it has a kitchen cleaner, mask, body sponge,
Products that may directly touch the human body or enter the body, such as cosmetic puffs and underwear pads, can also be used with confidence.

Further, the present invention has a remarkable effect on Staphylococcus aureus, and thus is extremely excellent as a kitchen cleaner or the like.

In particular, the second, fourth and fourth chitosan contents of 1 to 12%,
In the case of the sixth invention, the above-mentioned excellent antibacterial properties and the like can be obtained without deteriorating the performance of the polyurethane structure or the coating film, and the balance is very balanced.

[Safety data of chitosan] (Chitin-Chitosan Study Group Annual Report / 1988) (1) LD50 (oral);> 1.0 g / kg (mouse, rat),
No deaths (2) LD50 (subcutaneous);> 10 g / kg (mouse, rat), no deaths (3) Primary irritation to skin; almost non-irritating (4) Primary irritation to ocular mucosa; almost non-irritating; No abnormality found in cornea, etc. (5) Human patch test (transdermal); almost non-irritant and others.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshiro Abe 9-2-7 Kameido, Koto-ku, Tokyo Inside Taiyo Chemical Industry Co., Ltd. (72) Ryoichi Takanami 9-2-7 Kameido, Koto-ku, Tokyo Taiyo Chemical Industry Co., Ltd. (72) Inventor Isamu Aizawa 9-2-7 Kameido, Koto-ku, Tokyo Taiyo Chemical Industry Co., Ltd. (56) References JP-A-2-311561 (JP, A) (58 ) Surveyed field (Int.Cl. ⁷ , DB name) C09J 9/02-9/14 C08L 75/04-75/16 C09D 175/04-175/16

Claims (7)

(57) [Claims] An antimicrobial polyurethane foam produced by mixing a polyol, a catalyst, a blowing agent and a chitosan antibacterial agent, and then adding an organic isocyanate to the mixture, wherein the chitosan is dispersed in the polyurethane foam. An antimicrobial polyurethane foam characterized by being contained. 2. The antibacterial polyurethane foam according to claim 1, wherein the content of the chitosan is 1 to 12 parts by weight, when the total of the polyol, the organic isocyanate and the chitosan is 100 parts by weight. 3. The antibacterial polyurethane foam has an antibacterial property that, when contacted with S. aureus, reduces the number of bacteria after 6 hours at 37 ° C. to 1/20 or less of that at the start of contact. 2. The antibacterial polyurethane foam according to 2. 4. A polyol, an organic isocyanate, a catalyst,
An antimicrobial polyurethane elastomer produced using a raw material containing a crosslinking agent and chitosan, wherein chitosan is dispersed and contained in the polyurethane elastomer. 5. The antimicrobial polyurethane elastomer according to claim 4, wherein the content of the chitosan is 1 to 12 parts by weight, when the total amount of the polyol, the organic isocyanate, the crosslinking agent and the chitosan is 100 parts by weight. 6. An antibacterial polyurethane coating composition comprising a coating base containing a polyol and an organic isocyanate and chitosan. 7. The antibacterial polyurethane coating composition according to claim 6, wherein the content of the chitosan is 1 to 12 parts by weight, when the total of the polyol, the organic isocyanate and the chitosan is 100 parts by weight.