JPS6213426A - Production of coarse-cellular flexible urethane foam - Google Patents

Abstract

PURPOSE:To obtain the title urethane foam which is beautiful and has coarse cells, by reacting a polyol component with a polyisocyanate component under conditions including a specified rotation speed of the rotating impellers of a mixing head and a specified amount of a catalyst. CONSTITUTION:A mixture (A) of an at least bifunctional OH group-containing polyol component (a) (e.g., polyoxypropylene ether polyol of an OH value of 56) and, preferably, bi- to tetrafunctional polyol of a MW of 300-1,000 (e.g., diol) is reacted with an at least bifunctional polyisocyanate (e.g., tolylene diisocyanate) in the presence of a urethane formation catalyst (e.g., triethylenediamine) in an amount about 1.2-3 times that usually used by running the rotating impellers of a mixing head at a rotation speed of about 400-2,000rpm.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing a flexible urethane foam having coarse cells.

(Prior Art) When making a flexible urethane foam, conventional trifunctional polyols for flexible 7 ohms, polyisocyanates, catalysts, blowing agents, and other additives are used. Generally, the rotation speed of the rotating blade of the mixing head in the production of soft urethane foam is 4000 to 6000 r +1 + a,
In this case, 7 ohms with about 40 or more fine cells per 2.54 cm are obtained.

If the rotation speed is increased, finer cells of 7 ohms can be obtained, and conversely, if the rotation speed is decreased, the cells become coarser. However, when the rotational speed is reduced, contact between the chemical solutions decreases, and the internal block and the surrounding area of the 7 ohm become tattered due to the generation of unreacted substances, making it impossible to obtain a satisfactory product.

(Problems to be Solved by the Invention) An object of the present invention is to provide a method for producing a coarse flexible urethane foam having satisfactory product form and performance and having coarse cells.

(Means for Solving the Problems) The present invention provides a method for producing flexible polyurethane foam in which a polyol component having at least difunctional hydroxyl groups and an at least difunctional polyisocyanate component are reacted. The number of revolutions is about 40
The present invention relates to a method for producing a coarsely foamable flexible urethane foam, which is characterized in that the speed is lowered to 0 to 2000 rpm, and the amount of urethanization catalyst used is increased to about 1.2 to 3 times the amount normally used.

Examples of the polyol component used in the present invention include known soft trifunctional polyols for 7 ohms.

In addition, as trifunctional polyols, all known polyester polyols with a hydroxyl value (hereinafter referred to as OH value) in the range of 35 to 65 and polynylene polyols can be used, but in particular, polyoxypropylene with a hydroxyl value of 56 to 08 can be used. Ether polyols or polyoxyethylene propylene ether polyols are preferred.

The polyisocyanate component used in the present invention includes:
All known at least difunctional polyisocyanates can be used, but aromatic polyisocyanates are particularly preferred, such as 2,4- and 2,6-)lylene diisocyanate (TDI), orthotoluinone isocyanate) (TODI), sodium chloride diisocyanate) (ND
I), xylylene diisocyanate (MDI), 4,4
'-diphenylmethane diisocyanate) (MD I
), carposiimide-modified MDI (for example, Nippon Polyurethane Co., Ltd. MTL), polymethylene polyphenylisocyanate (PApH), polymeric polyisocyanate (for example, Sumitomo Bayer Urethane 44), etc. can be used alone or in combination.

In the present invention, when manufacturing urethane foam, the rotation speed of the rotating blade of the chemical mixing head is set at approximately 400 to 2000 rpm.
m is much smaller than the normal rotation speed, and the amount of urethanization catalyst used is about 1.2 of the amount used at the normal rotation speed.
It is characterized by increasing the amount by ~3 times. This will give you the desired 7 ohms with a clean 7 ohm and only a rough cell. As a catalyst, a known urethanization catalyst can be used, such as a tin catalyst such as T-9 (manufactured by Yoshitomi Pharmaceutical Co., Ltd., tin catalyst), triethylenediamine (manufactured by 7-Dolly Co., Ltd., amine catalyst, Dapco), etc. , amine catalysts, and other catalysts can be used. If the amount of catalyst is less than 1.2 times, 7 ohm is incomplete, and if it exceeds 3 times, 7 ohm tends to shrink.

In the present invention, in addition to the balance between the rotational speed of the rotating blade and the amount of catalyst, it is preferable to use a bifunctional to tetrafunctional polyol with a molecular weight (MW) of 300 to 1000 in combination with the polyol component to obtain a more perfect 7 ohm.

Such polyols include diols, polyols,
Examples include PO adducts of Bis7el/-A, aromatic amine-based polyols, and commercially available products include, for example, BISQL-
2P [manufactured by Toho Chiba Chemical, PO (propylene oxide) adduct of bisphenol A], GR-30 [manufactured by Substitute Yakuhin, aromatic amine-based polyol], Dial 200
0 (manufactured by Asahi Denka, Diol, MW2000), K S
570 (manufactured by Dai-Kogyo Seiyaku, M W 400° OH value 5
70], etc.

In the present invention, the ratio of the soft 7-ohm trifunctional polyol and the polyol with a MW of 300 to 1000 is preferably 90 to 99 parts (parts by weight, hereinafter the same) of the former and 1 to 10 parts of the latter. .

In the present invention, when making a urethane foam by reacting polyols with incyanates, etc., the isocyanate index is preferably 103 to 130, but can be increased or decreased as appropriate based on desired physical properties.

Further, the present invention can be applied not only to a 7 ohm soft slab but also to a 7 ohm mold.

Furthermore, in the present invention, in order to produce flexible polyurethane 7 ohm, foaming M and a foam stabilizer are added, and if necessary, a flame retardant,
Pigments, fillers, etc. are used, but there are no restrictions and all known ones can be used.

(Example) A detailed explanation will be given below based on reference examples and examples.

Reference Example I PPG 3000 [manufactured by Mitsui Nisso, trifunctional polypropylene polyol, 5631000 g of 08 valence] was placed in a 2 liter beaker, and T-9 [tin catalyst manufactured by Yoshitomi Pharmaceutical] 1
．． 3g and foam stabilizer [Made by Toray Silicone, S H190
) 10g was added and stirred for 10 minutes, which is called Solution A.

A separate 100cc beaker with water 39. Take NMM [
Nippon Nyukasou, N-methylmorpholine) 5. Og and triethylenediamine [manufactured by 7-Dolly, Dabco] 0
．． 5g was added and stirred, and this was designated as Solution B.

Place 202.26 g of liquid A in a 500 cc beaker, then add 8.9 g of liquid B, and adjust the temperature to 25°C while stirring.

On the other hand, take 106 g of TDI in another beaker and adjust the temperature to 22°C. Pass the mixture of A and B through the rotor') 1500 rpm
After stirring for 10 seconds at m, the above TDT was added thereto, and after stirring for 6 seconds, the mixture was placed in a 240 x 240 x 200+*m open mold, and placed in a dryer at 100°C for 10 minutes to foam.

The resulting 7 ohm condition is defective and JIS K
- The number of cells measured by the method of 6402 is approximately 45/
It was 2.54c111, fine cell 7 ohm.

The blending ratio is shown in table fjS1.

Examples 1 to 3 Soft urethane foams were prepared in the same manner as in Reference Example 1, except that the blending ratios and conditions shown in Table 1 were used. The results are also shown in Table 1.

Table 1 Reference Example 2 PPG 3000 (950g) was placed in a 2 liter beaker, T-9 (1.3g) and SI (190
(Loll> is added and stirred, and this is called liquid C. In another beaker, add 20 g of BISQL-2P [manufactured by Toho Chiba Chemical, PO adduct of bisphenol A, OH value 320], G
R-30 (manufactured by Ota Pharmaceutical, aromatic amine-based polyol,
08 value: 400) and 60 g of 1/':/:t-ru (manufactured by Asahi Denka, OH value: 56) were taken and stirred, and this was used as liquid D.

Solution B of Reference Example 1, the above C, D! A soft urethane foam was prepared in the same manner as in Reference Example 1, using TDI and each component in the proportions shown in Table 2. The results are also shown in Table PIIJ2.

Examples 4 to 6 Soft urethane foams were prepared in the same manner as in Reference Example 2, except that the blending ratios and conditions shown in Table 2 were used. The results are also shown in Table 2.

Table 2 (that's all)

Claims (2)

[Claims] (1) In a method for producing a flexible polyurethane foam in which a polyol component having at least a difunctional hydroxyl group and an at least difunctional polyisocyanate component are reacted, the rotation speed of the rotating blade of the mixing head is set to about 400.
2000 rpm, and the amount of the urethanization catalyst used is increased to about 1.2 to 3 times the usual amount. (2) As a polyol component, the molecular weight is 300 to 10.
The manufacturing method according to claim 1, in which a di- to tetrafunctional polyol of 0.00 is used in combination.