JPH1045700A - Diisocyanate compound and its oligomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a diisocyanate compound capable of inducing an oligomer free from coloring and turbidity and having low viscosity by keeping total halogen content and a hydrolyzable halogen content in the compound in specific amounts or below respectively. SOLUTION: This compound has <=2000ppm total halogen content and <=20ppm hydrolyzable halogen content. The compound is obtained by a method, etc., adding, e.g. an alkaline substance (e.g. tetramethylammonium 2- ethylhexanoate) to a diisocyanate compound obtained by a phosgene method to lower the hydrolyzable halogen. A polyisocyanate oligomer having 400-20000 number-average molecular weight can be obtained by using the compound and an urethane product (coating material, etc.) excellent in weather resistance, etc., can be obtained from the oligomer. Thereby, a hydrolyzable halogen having adverse influence on quality, etc., is lowered to provide a raw material for urethane product having good quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a diisocyanate compound used for paints, adhesives, printing inks, elastomers and the like, and a polyisocyanate oligomer thereof.

[0002]

2. Description of the Related Art Isocyanate compounds such as diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 1,3-xylylene diisocyanate, and 1,3- (diisocyanato) cyclohexane are known as monomers or polyisocyanate oligomers. Combined with various polyols, and chain extenders such as short-chain diols and diamines, as urethane products such as polyurethane paints, adhesives, printing inks, elastomers, sealing materials, etc., for automobiles, construction, civil engineering, electric and electronics It is used in a wide range of fields such as equipment and sports equipment.

[0003] Known polyisocyanate oligomers include buret-type polyisocyanate oligomers derived from isocyanate compounds, isocyanurate-type polyisocyanate oligomers, and urethane-modified polyisocyanate oligomers.

However, when a conventional isocyanate compound is reacted with an active hydrogen compound such as a polyol or a polyamine to form a polyisocyanate oligomer, coloring or turbidity is caused, thereby impairing the appearance as a urethane product or deteriorating its performance. The related industries are keen to improve.

Further, conventional urethane products using isocyanate compounds or polyisocyanate oligomers have insufficient weather resistance, heat resistance, water resistance and the like when used for a long period of time. The appearance of compounds and polyisocyanates is expected, and several proposals have been made.

[0006] For example, Japanese Patent Application Laid-Open No. 4-246411 discloses a number average molecular weight derivative derived from an aliphatic, alicyclic, araliphatic diisocyanate having 6 to 20 carbon atoms and an aromatic polyisocyanate monomer having 8 to 40 carbon atoms. Molecular weight 400
It has been proposed that a urethane product having excellent weather resistance can be obtained by using a polyisocyanate oligomer containing substantially no halogen in the range of 20,000 to 20,000.

Japanese Patent Application Laid-Open No. 2-311452 discloses that
It is described that the use of a diisocyanate compound having a chlorine content of only 10 ppm or less improves the corrosion resistance and weather resistance of a polyurethane product.

[0008]

At present, diisocyanate compounds are industrially produced by a direct reaction between a polyamine and phosgene. Therefore, in the diisocyanate compound, at a concentration of several thousand ppm, unreacted phosgene, a halogen compound which is easily hydrolyzed such as a by-product of the reaction, chloroformate or a reaction intermediate such as mono- and dicarbonyl chloride compounds, Further, non-hydrolyzable halogen compounds such as alkyl chloride and alkyl bromide are contained as impurities.

The above-mentioned JP-A-4-246411 and JP-A-2-31452 are limited only to diisocyanate compounds produced without using phosgene, and are currently commercially available diisocyanate compounds. There is a demand from related industries for polyisocyanate oligomers obtained from the above, which are less colored and less turbid, and urethane products excellent in weather resistance and heat resistance.

[0010]

Means for Solving the Problems The present inventor has conducted intensive studies in view of the above situation, and as a result, it has been found that not all of the halogen compounds contained in the diisocyanate compound, but the hydrolyzable halogen is the coloring of the polyisocyanate oligomer. Causes turbidity, weather resistance of urethane products,
The inventors have found that the heat resistance is adversely affected, and that if the amount of halogen that does not hydrolyze is in an appropriate amount, the quality of the polyisocyanate oligomer and the quality of the urethane product obtained therefrom are not adversely affected.

That is, according to the present invention, the total halogen content is 200
0 ppm or less, and a diisocyanate compound having a hydrolyzable halogen content of 20 ppm or less, and a diisocyanate compound having a total halogen content of 2000 ppm or less and a hydrolyzable halogen content of 20 ppm or less, Number average molecular weight is 40
It is a polyisocyanate oligomer of 0 to 20,000.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The total halogen content in the present invention is the sum of the non-hydrolyzable halogen content and the hydrolyzable halogen content, and the total halogen content is ASTM D
It is measured by the method of -1638, and the content of the hydrolyzable halogen is measured according to JISK-1556. The total bromine content is measured using fluorescent X-rays.

The hydrolyzable halogen compound includes a halogen compound hydrolyzed like an inorganic acid such as hydrogen chloride, unreacted phosgene, chloroformate which is a by-product of the reaction, and a mono-product which is a reaction intermediate. And dicarbonyl chloride compounds, such as acetyl bromide,
Halogen compounds that hydrolyze with water, alcohols, and the like at temperatures from normal temperature to 150 ° C. are included.

The non-hydrolyzable halogen compound is not an inorganic acid such as hydrogen chloride, and is a halogen compound which does not hydrolyze with water or alcohol at a temperature of from room temperature to 150 ° C. For example, there are alkyl halide compounds such as butyl bromide and butyl chloride.

The total halogen content of the diisocyanate compound of the present invention is 2,000 ppm or less. If the total halogen content exceeds 2000 ppm, the purity of the diisocyanate compound will decrease, and the performance of the urethane product obtained therefrom will decrease. Since a small amount of the halogenated alkyl compound becomes a heat-resistant substance when an oligomer is obtained, a preferable range of the total halogen content of the diisocyanate compound of the present invention is 30 to 1500 ppm.

The diisocyanate compound of the present invention has a hydrolyzable halogen content of 20 ppm or less. When the content of the hydrolyzable halogen is more than 20 ppm, the resulting polyisocyanate oligomer causes undesired coloring and turbidity, and also lowers heat resistance and weather resistance.

The method for producing the diisocyanate compound of the present invention is not particularly limited. Conventionally, industrially produced diisocyanate compounds contain halogen because phosgene is used as a raw material, but diisocyanate compounds produced by these phosgene are distilled,
20 pp hydrolyzable halogen by purification means such as adsorption
m or less. For example, a non-hydrolyzable halogen compound as a heat resistance improver may be added to a diisocyanate compound produced without using phosgene at 20 pp.
m or more may be added, and such a polyisocyanate oligomer does not cause coloring and turbidity.
It does not adversely affect the weather resistance and heat resistance of urethane products.

Further, as a method for producing the diisocyanate compound of the present invention, a diisocyanate compound produced by a phosgene method to which an alkaline substance is added to reduce the hydrolyzable halogen can be used. As the alkaline substance to be added to the diisocyanate compound, sodium, potassium and quaternary ammonium salts of a carboxylic acid are preferably used, and examples thereof include tetramethylammonium-2-ethylhexanoic acid. Such a method of adding an alkaline substance is an advantageous method because the hydrolyzable halogen of the diisocyanate compound produced by phosgene can be reduced very easily.

As the diisocyanate compound used in the present invention, any of aromatic, alicyclic and aliphatic compounds can be used. For example, diphenylmethane diisocyanate,
2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,4-naphthalene diisocyanate, 1,5-naphthalene diisocyanate, 1,6-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, isophorone diisocyanate, norbornane diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,3-
(Diisocyanate) cyclohexane, tetramethylene diisocyanate, pentamethylene diisocyanate,
Hexamethylene diisocyanate, cyclopentylene-
There are 1,3-diisocyanate, 1,2-bis (isocyanatomethyl) cyclohexane, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane and the like. One or two selected from
More than one species is used.

The polyisocyanate oligomer of the present invention can be produced by a known method using these diisocyanate compounds. The molecular weight of the polyisocyanate oligomer of the present invention is 400 as a number average molecular weight.
~ 20,000. When the number average molecular weight exceeds 20,000, the fluidity is remarkably deteriorated, and handling becomes difficult.

The polyisocyanate oligomer includes a polyisocyanate oligomer having a bond such as buret, urethane, isocyanurate, and allophanate. Polyisocyanate oligomers containing urethane groups are produced by reacting a diisocyanate compound with a polyfunctional alcohol compound (Japanese Patent Publication No. 45-11146).
JP, JP-A-56-159212, JP-A-57-159212
Publication No. 2004016).

The burette group-containing polyisocyanate oligomer is obtained by reacting an excess of a diisocyanate compound with a burette agent. As the burette agent, a compound capable of forming a burette bond by reacting with an isocyanate group, for example, water , Aliphatic tertiary alcohols,
Examples thereof include aliphatic primary amines and N, N'-disubstituted ureas (JP-A-49-134629).

The polyisocyanate oligomer containing an isocyanurate group is produced by reacting a diisocyanate compound in the presence of a suitable catalyst (JP-A-55-38380, JP-A-57-83560).
JP, JP-A-59-22916, etc.).

Also, two or more kinds of bonds can be introduced by combining the above methods. Further, one type of diisocyanate compound as a raw material may be used, or two or more types may be used in combination. The ratio of the diisocyanate compound when using a plurality of diisocyanate compounds,
It depends on the purpose of use. The polyisocyanate oligomer of the present invention may be a mixture of different types of polyisocyanate oligomer.

[0025]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

The degree of coloring was measured by the Hazen color number method described in JIS K 6901. Alternatively, the sample was placed in a 10 mm cell, and the YI value and ΔE value were measured with a color difference meter (COH-300A manufactured by Nippon Denshoku Industries Co., Ltd.).
In both cases, the greater the value, the greater the degree of coloring.

Production Example 1 1,3-Bis (isocyanatomethyl) cyclohexane (hereinafter abbreviated as 1,3-BIC) obtained by the phosgene method is referred to as isocyanate A. Isocyanate A has a total halogen content of 1480 ppm, a hydrolyzable halogen content of 40 ppm and a total bromine content of 210 ppm. The isocyanate A does not fall under the diisocyanate compound of the present invention because it contains a large amount of hydrolyzable halogens.
The number of colors was 10.

Production Example 2 0.5 kg was added to 1 kg of 1,3-BIC by the phosgene method.
Is added at room temperature, and the precipitated salt is filtered to obtain 1,3-BIC as isocyanate B. Isocyanate B has a total halogen content of 14
00 ppm, hydrolysable halogen content is 10 ppm,
The total bromine content is 200 ppm, and the isocyanate B corresponds to the diisocyanate compound of the present invention. The number of colors was 10.

Production Example 3 Isocyanate C is prepared by adding butyl bromide to 1,3-BIC without using phosgene so that the bromine content becomes 200 ppm. Isocyanate C has a total halogen content of 200 ppm, hydrolyzable halogen content of 0.1 ppm, and total bromine content of 200 ppm. Isocyanate C corresponds to the diisocyanate compound of the present invention. The number of colors was 10.

Production Example 4 Isocyanate D is prepared by adding acetyl bromide to 1,3-BIC without phosgene so that the bromine content becomes 200 ppm. Isocyanate D has a total halogen content of 200 ppm, a hydrolyzable halogen content of 200 ppm, and a total bromine content of 200 ppm, and the isocyanate D does not fall under the diisocyanate compound of the present invention. The number of colors was 10.

Example 1 235 g of polypropylene glycol having an average molecular weight of 2,000 (Adeka Polyether P-2000 manufactured by Asahi Denka) and 45 g of isocyanate B ([NCO] / [OH] = 2) were mixed at room temperature, and the mixture was taken for about one hour. And warm to 130 ° C,
The reaction was performed at this temperature for 8 hours. The number average molecular weight of the obtained oligomer was 5,800, and the viscosity at 25 ° C. was 5,700 c.
ps. The number of colors was 10.

Example 2 The procedure of Example 1 was repeated, except that Isocyanate C was used instead of Isocyanate B. The number average molecular weight of the obtained oligomer was 5,900 and the viscosity at 25 ° C. was 6200.
cps. The number of colors was 10.

Comparative Example 1 The same operation as in Example 1 was carried out except that isocyanate A was used instead of isocyanate B. The number average molecular weight of the obtained oligomer is 6050 and the viscosity at 25 ° C. is 6700.
cps. The number of colors was 30.

Comparative Example 2 The same procedure as in Example 1 was carried out except that isocyanate D was used instead of isocyanate B. The number average molecular weight of the obtained oligomer is 10,000, and the viscosity at 25 ° C. is 193.
00 cps, and the number of colors was 110.

From the above Examples and Comparative Examples, even if the total halogen content is 200 ppm or more, if the hydrolyzable halogen content is 20 ppm or less, no coloring occurs, the viscosity is low, and the value of the number average molecular weight is small. It can be seen that an oligomer is obtained.

Example 3 A 1942 g isocyanate C was placed in a flask, and 100
C. and stirred. 134 g of trimethylolpropane melted at 80 ° C. was added dropwise over 2 hours to react with isocyanate. After the completion of the dropwise addition, the mixture was further heated for 2 hours to carry out the reaction. Then, 0.2 mmH
1,3-BIC from the reaction product at 200 ° C. under reduced pressure
The monomer was removed to obtain a urethane-modified polyisocyanate oligomer. This oligomer was dissolved in ethyl acetate to give a 75% solution. The oligomer solution has a YI value of 0.1.
At 45, the viscosity at 25 ° C. was 1625 cps.

Comparative Example 3 The same procedure as in Example 3 was carried out except that isocyanate A was used instead of isocyanate C. YI of oligomer solution
The value was 1.34 and the viscosity at 25 ° C. was 2050 cps.

From Example 3 and Comparative Example 3, even if the total halogen content is 200 ppm or more, if the hydrolyzable halogen content is 20 ppm or less, the oligomer obtained therefrom is not colored and has low viscosity. You can see that.

Application Example 1 A 75% solution of the urethane-modified polyisocyanate oligomer obtained in Example 3 in ethyl acetate and an acrylic polyol (Acrydic A801 manufactured by Dainippon Ink) were added to [N
CO] / [OH] = 1, titanium oxide (Taipe CR90 manufactured by Ishihara Sangyo Co., Ltd.) was blended so as to be 40% based on the weight of the resin, and painted so that the dry film thickness became 30 μm.
C. and dried at 50 RH% for 7 days. This coating film was subjected to an accelerated weather resistance test using an eye super UV tester under the following exposure conditions. UV irradiation time was 500 min.
00 min was performed at a cycle interval of no irradiation, water injection time of 10 min, and for the next 100 min, a cycle interval of no injection was performed at a black panel temperature of 63C. 20
The gloss retention after 0 hour was 87%, and the color difference ΔE 0.53
Met.

Comparative Application Example 1 The same operation as in Application Example 1 was carried out except that a 75% ethyl acetate solution of the urethane-modified polyisocyanate oligomer obtained in Comparative Example 3 was used. The test result after 200 hours of accelerated weather resistance was a gloss retention of 75% and a color difference ΔE of 1.72.

From the above application examples and application comparison examples, it can be seen that the weather resistance of a coating film of an oligomer obtained from an isocyanate having a total halogen content of 200 ppm or more and a hydrolyzable halogen content of 20 ppm or less is observed. I understand.

[0042]

According to the present invention, the total halogen content is 2000 p.
pm or less and a hydrolyzable halogen content of 20
The polyisocyanate oligomer obtained from a diisocyanate compound of not more than ppm has no coloring or turbidity,
Low viscosity. In addition, urethane products (such as paints) having excellent weather resistance and the like can be obtained from the oligomer. Therefore, the diisocyanate compound and its oligomer of the present invention are extremely excellent industrial materials.

Claims (3)

[Claims] 1. A diisocyanate compound having a total halogen content of 2000 ppm or less and a hydrolyzable halogen content of 20 ppm or less. 2. A polyisocyanate oligomer having a number average molecular weight of 400 to 20,000, derived from a diisocyanate compound having a total halogen content of 2000 ppm or less and a hydrolyzable halogen content of 20 ppm or less. 3. The method for producing a diisocyanate compound according to claim 1, wherein an alkaline substance is added to the diisocyanate compound produced by the phosgene method.