JPH11323126A - Flexible polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible polyurethane foam made proof against discoloration and discoloration due to migration. SOLUTION: There is provided a flexible polyurethane foam prepared by foaming a polyurethane material containing 100 pts.wt. polyol component, 0.05-2.0 pts.wt. phenolic antioxidant having a molecular weight of 300 or above and/or 0.1-3.0 pts.wt. benzotriazole ultraviolet absorber and/or 0.5-6.0 pts.wt. phosphorus antioxidant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible polyurethane foam, and more particularly to a flexible polyurethane foam having no problem of discoloration or migration discoloration, and useful as a pad material for clothing such as a brassier pad material, a shoulder pad material, a hanger pad material and the like. Related to polyurethane foam.

[0002]

2. Description of the Related Art A flexible polyurethane foam has a good cushioning property, does not settle when used for a long time or is repeatedly used like cotton, and has a soft and good feel. It is widely used as a pad material for clothing such as a pad material.

[0003]

A conventional flexible polyurethane foam contains BHT (dibutyl cresol) as an antioxidant in a polyol raw material at the time of production, and the BHT causes discoloration and transfer discoloration of the foam itself. (Dyeing stains on fabrics and the like that come into contact with the flexible polyurethane foam.) That is, when foaming is performed with a blend containing BHT as a polyurethane raw material, BHT remains in the foam after foaming.
T reacts with nitrogen oxides contained in the atmosphere to yellow the urethane foam itself. In addition, since BHT has sublimability, it volatilizes and adheres to a nearby fabric, similarly discoloring the fabric.

[0004] A flexible polyurethane foam also changes color under the influence of ultraviolet rays.

[0005] The discoloration and migration discoloration of such foams are serious defects for flexible polyurethane foams for clothing use.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a flexible polyurethane foam which prevents discoloration and migration discoloration of the foam itself.

[0007]

The flexible polyurethane foam of the present invention satisfies at least one of the following, preferably at least two, more preferably at least one of the following and substantially free of BHT: It is characterized by foaming the raw material.

A phenolic antioxidant having a molecular weight of 300 or more is added in an amount of 0.05 to 100 parts by weight of the polyol component.
２．０2.0 parts by weight. The benzotriazole-based ultraviolet absorber is contained in an amount of 0.1 to 3.0 parts by weight based on 100 parts by weight of the polyol component. The phosphorus-based antioxidant is contained in an amount of 0.5 to 6.0 parts by weight based on 100 parts by weight of the polyol component.

[0009] The migration discoloration of the flexible polyurethane foam is B
In the present invention, anti-migration and discoloration are prevented by changing the antioxidant in the raw material used from BHT to an antioxidant having a molecular weight larger than that of BHT.

In the present invention, a high molecular weight phenolic antioxidant having a molecular weight of 300 or more is used as an antioxidant having a large molecular weight.

Further, since yellowing of a flexible polyurethane foam is greatly affected by ultraviolet rays, in the present invention, discoloration is prevented by adding an ultraviolet absorber.

Furthermore, the N of the flexible polyurethane foam itself
For preventing discoloration of Ox and discoloration during hot pressing, a phosphorus-based antioxidant is effective.

[0013]

Embodiments of the present invention will be described below in detail.

In the present invention, a phenolic antioxidant having a molecular weight of 300 or more is compounded in a polyurethane raw material,
By substantially not incorporating BHT having a small molecular weight, migration discoloration due to volatilization of the phenolic antioxidant is prevented.

The phenolic antioxidant has a molecular weight of 3
If it is less than 00, volatilization of the phenolic antioxidant occurs,
Migrating discoloration occurs. The molecular weight of the phenolic antioxidant is preferably at least 400, particularly preferably at least 600. As such a phenolic antioxidant, a phenolic antioxidant such as "Nowgard 445" manufactured by Uniroyal or "AO80" manufactured by Asahi Denka Kogyo KK can be used.

If the amount of the phenolic antioxidant having a molecular weight of 300 or more is less than 0.05 part by weight based on 100 parts by weight of the polyol component in the polyurethane raw material, the antioxidant performance is weak and the stability of the raw material itself is reduced. . If the amount exceeds 2.0 parts by weight, the appearance of the obtained flexible polyurethane foam will be disturbed, and the raw material cost will increase. Therefore, the blending amount of the phenolic antioxidant having a molecular weight of 300 or more depends on the amount of the polyol component 1 in the polyurethane raw material.
0.05 to 2.0 parts by weight with respect to 00 parts by weight.

In the present invention, by blending a benzotriazole-based ultraviolet absorber into a polyurethane raw material,
Prevents yellowing of the foam itself due to ultraviolet light. Examples of the benzotriazole-based ultraviolet absorber include “T-213” manufactured by Ciba Geigy and “LA-3” manufactured by Asahi Denka Kogyo KK.
1 "can be used.

If the blending amount of the benzotriazole-based ultraviolet absorber is less than 0.1 part by weight with respect to 100 parts by weight of the polyol component in the polyurethane raw material, a sufficient effect cannot be obtained. If the amount exceeds the above range, the appearance of the obtained flexible polyurethane foam will be disturbed, and the raw material cost will increase. Accordingly, the blending amount of the benzotriazole-based ultraviolet absorber is 0.1 to 3.0 parts by weight based on 100 parts by weight of the polyol component in the polyurethane raw material.

In the present invention, discoloration of the foam itself by NOx and discoloration during hot pressing can be prevented by blending a phosphorus-based antioxidant into the polyurethane raw material. As the phosphorus antioxidants, "3010", "1
178 "can be used.

If the amount of the phosphorus-based antioxidant is less than 0.5 part by weight with respect to 100 parts by weight of the polyol component in the polyurethane raw material, a sufficient effect cannot be obtained, and the amount of the phosphorus-based antioxidant is 6.0.
If the amount exceeds 0 parts by weight, the appearance of the obtained flexible polyurethane foam will be disturbed, and the raw material cost will rise.
Therefore, the compounding amount of the phosphorus-based antioxidant is 0.5 to 6.0 parts by weight based on 100 parts by weight of the polyol component in the polyurethane raw material.
0 parts by weight.

In the present invention, in order to prevent both discoloration and discoloration of the foam and the foam itself, the polyurethane raw material does not substantially contain BHT, and the phenol having a molecular weight of 300 or more is added to 100 parts by weight of the polyol component. Contains 0.05 to 2.0 parts by weight of a system-based antioxidant, 0.05 to 1.0 part by weight of a benzotriazole-based ultraviolet absorber, and 0.5 to 6.0 parts by weight of a phosphorus-based antioxidant. Is preferred.

The flexible polyurethane foam of the present invention is produced according to a conventional method using the following usual raw material blending except that a polyurethane material containing a predetermined antioxidant is used as a raw material for polyurethane. Is done. The NCO index of the raw material is preferably 90 to 120.

<Polyurethane raw material blend (parts by weight)> Polyol component: 100 Isocyanate component: 10 to 80 Catalyst: 0.01 to 2.0 Blowing agent: 1.0 to 25.0 Foam stabilizer: 0.1 to 3 The polyol component is not particularly limited, but has a molecular weight of 2
It is preferable to use those having a OH value of about 500 to 5000 and an OH value of about 40 to 60.

The isocyanate component is not particularly limited, and is an organic polyisocyanate having two or more isocyanate groups in one molecule, and includes aliphatic and aromatic polyisocyanate compounds and modified products thereof. . Examples of the aliphatic polyisocyanate include:
Hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate,
Methylcyclohexane diisocyanate and the like,
Examples of the aromatic polyisocyanate include toluene diisocyanate, diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, and the like. In addition, these modified products include carbodiimide modified products and prepolymer modified products. The polyisocyanate preferable in the present invention is an aromatic polyisocyanate or a modified product of the aromatic polyisocyanate, and particularly preferably includes diphenylmethane isocyanate, toluene diisocyanate, diphenylmethane diisocyanate and the like.

As the foaming agent, all foaming agents used for producing polyurethane foam can be used. For example, trichlorofluoromethane as a low boiling point inert solvent, freon-based compounds such as dichlorodifluoromethane, and the like,
Water, acid amides, nitroalkanes, etc. that generate gas by methylene chloride, liquefied carbon dioxide gas reaction,
There are sodium bicarbonate, ammonium carbonate, and the like that generate gas upon thermal decomposition. Among these, preferable foaming agents include methylene chloride, water and the like.

As the foam stabilizer, silicone oil can be used.

As the catalyst, all catalysts used for producing ordinary urethane foam can be used. Examples include tin-based catalysts such as dibutyltin diurarate and stannas octoate, and tertiary amines such as triethylamine and tetramethylhexamethylenediamine.

The polyurethane foam of the present invention may further contain, if necessary, a surfactant, a flame retardant and other auxiliaries. As the surfactant, a silicone-based surfactant is usually used. As the flame retardant, tris (2-chloroethyl) phosphate, tris (2,3
Organic powders such as urea and thiourea or inorganic powders such as metal hydroxide and antimony trioxide can be used in addition to conventionally known flame retardants such as -dibromopropyl) phosphate.

Examples of other auxiliaries include coloring powders such as pigments and dyes, powders such as talc and graphite, short glass fibers, and other inorganic extenders and organic solvents.

[0030]

The present invention will be described more specifically below with reference to examples and comparative examples.

Examples 1 to 9 and Comparative Examples 1 to 3 Polyurethane raw materials having the composition shown in Table 1 were prepared according to a conventional method.
C. to produce a flexible polyurethane foam.
With respect to this flexible polyurethane foam, discoloration discoloration, ultraviolet discoloration and NOx discoloration were examined by the following methods. The results are shown in Table 1.

<Transfer discoloration> The urethane foam is wrapped in a polyester cloth and left at 50 ° C. for 48 hours. Then, the polyester cloth is exposed to a NOx concentration of 50 ppm for 2 hours, and the polyester cloth is further left at 50 ° C. for 30 days. did. Thereafter, with respect to this polyester fabric, a YI value based on a white plate was measured with “ZE2000” manufactured by Nippon Denshoku Co., Ltd. The larger the YI value, the greater the discoloration.

<Ultraviolet Discoloration> After irradiating the polyurethane foam with an ultraviolet ray using one carbon arc lamp for 9 hours, the YI value based on a white plate was measured with “ZE2000” manufactured by Nippon Denshoku Co., Ltd.

<Discoloration of NOx> After the polyurethane foam was allowed to stand in an atmosphere of 500 ppm NOx for 2 hours, the YI value based on a white plate was measured using “ZE2000” manufactured by Nippon Denshoku.

[0035]

[Table 1]

From Table 1, it can be seen that according to the present invention, discoloration and migration discoloration of the foam itself are prevented.

[0037]

As described above in detail, according to the flexible polyurethane foam of the present invention, there is provided a flexible polyurethane foam which is free from problems of discoloration and migration discoloration of the foam itself and which is suitable as a pad material for various kinds of clothing.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 5/49 C08K 5/49 // C08L 75:04

Claims (6)

[Claims] 1. A phenolic antioxidant having a molecular weight of 300 or more is added in an amount of from 0.05 to 100 parts by weight of a polyol component.
A flexible polyurethane foam obtained by foaming a polyurethane raw material containing 2.0 parts by weight. 2. A flexible polyurethane foam obtained by foaming a polyurethane material containing 0.1 to 3.0 parts by weight of a benzotriazole-based ultraviolet absorber with respect to 100 parts by weight of a polyol component. 3. A polyol component 10 comprising a phosphorus-based antioxidant.
A flexible polyurethane foam obtained by foaming a polyurethane raw material containing 0.5 to 6.0 parts by weight per 0 parts by weight. 4. The flexible polyurethane foam according to claim 1, wherein the polyurethane raw material contains a benzotriazole-based ultraviolet absorber in an amount of 0.1 to 3.0 parts by weight based on 100 parts by weight of the polyol component. 5. The polyurethane raw material according to claim 1, wherein the polyurethane raw material contains 0.5 to 6.0 parts by weight of a phosphorus-based antioxidant based on 100 parts by weight of the polyol component. Characteristic flexible polyurethane foam. 6. The flexible polyurethane foam according to claim 1, wherein the polyurethane raw material does not substantially contain dibutyl cresol.