JPH0291117A - Blocked polyisocyanate dispersion - Google Patents

Abstract

PURPOSE:To improve storage and to suppress foaming by dispersing specified reaction and compd. in water. CONSTITUTION:A reaction product is obtd. by reacting a compd. of the formula (wherein x is 10-60; y is 0-60; n is 1-3) with an isocyanate compd. having one or more active isocyanate groups in its molecule (e.g., hexamethylene diisocyanate). 0.2-10wt.% said product and 0.1-3wt.% at least one compd., selected from an alkali metal alkylnaphthalenesulfonate, an alkali metal dialkyl sulfosuccinate, an alkylphenol-ethylene oxide adduct, a higher alcohol-ethylene oxide adduct and a polyisocyanate compd. blocked with an active hydrogen compd. except those of the formula, are dispersed in a medium wherein water is a main component.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to blocked polyisocyanate dispersions useful as paints, adhesives, varnishes, and the like.

[Prior Art] Various blocked polyisocyanate dispersions have been used in the past. These blocked polyisocyanate dispersions are produced by processing blocked polyisocyanate compounds in which the incyanate groups of various polyisocyanate compounds are blocked with a compound having active hydrogen in the presence of a surfactant using a ball mill, various media dispersers, homogenizers, etc. For example, in Example 1 of JP-A-57-56584,
4. A method of dispersing a phenol block of 4-diphenylmethane diisocyanate in water using a ball mill in the presence of dioctyl sulfosuccinate Na salt as a surfactant, and Example 1 of JP-A-55-152815. discloses a method in which an ε-caprolactam block of polymethylene polyphenylisocyanate is dispersed in water with methyl cellulose, sodium alkyl sulfonate, and polyethylene glycol monolaurylate using a ball mill.

[Problems to be Solved by the Invention] When these blocked polyisocyanate dispersions are left for a long period of time, the blocked polyisocyanate compound separates from water and settles and sticks to the bottom of the container, making it difficult to use. There was a problem. In addition, when the blocked polyisocyanate dispersion is diluted with water or mixed with other aqueous liquids such as epoxy compound aqueous solution, polyester aqueous solution, rubber latex, resorcinol/formaldehyde resin aqueous solution, etc. during stirring, Since foaming occurs violently during the squeezing process after application to woven or knitted fabrics, there are problems with operability and the use of antifoaming agents.

(The following is a blank space) [Means for Solving the Problems] The object of the present invention described above is A. A compound represented by the following general formula (I) (however, the above (
I) an incyanate compound having one or more active isocyanate groups in one molecule; and at least one selected from the following (a) to (d):
Species compound (a) Alkali metal salt of alkylnaphthalene sulfonic acid (b) Alkali metal salt of dialkyl sulfosuccinic acid (C) Ethylene oxide adduct of alkylphenol (d) Ethylene oxide adduct of higher alcohol, and C8 [I] Number of holes above A polyisocyanate compound blocked with a compound having an active hydrogen (hereinafter referred to as a blocked polyisocyanate compound), and the main component of the medium is water.

The compound represented by the general formula [I] of the present invention includes:
For example, monostyrylphenol ethylene oxide (
(hereinafter referred to as EO) adduct (x in formula (I) = 10 to 6
0), EO adduct of distyrylphenol (x = 10 to 60 in formula (I)), EO adduct of tristyrylphenol (x = 10 to 6o in formula (I)), EO of monostyrylphenol・Oxypropylene (hereinafter referred to as PO) adduct (X in formula (I) = 10 to 60. y = o to 60
), EO-PO adduct of distyrylphenol (formula (I
, X in l=10-60. y=0-60), EO-PO adduct of tristyrylphenol (x=10-6 in the formula
0. Among these compounds, x=13-40 in formula [I] can be mentioned. Compounds where y=0 to 10 are preferred. These compounds can be used alone or in combination. The isocyanate compound having one or more active isocyanate groups in one molecule which is reacted with the compound represented by the above formula [I] is, for example, methyl isocyanate, ethyl isocyanate, propyl isocyanate, isocyanate, etc. Monoisocyanate compounds such as isobutyl acid, hexamethylene monoisocyanate, phenyl isocyanate, diisocyanate compounds such as hexamethylene diisocyanate, 2.4-tolylene diisocyanate, 4.4゛-diphenylmethane diisocyanate, triphenylmethane triisocyanate and triisocyanate compounds such as trimethylolpropane/hexamethylolpropane adducts. The reaction product of the above formula (I) compound and these isocyanate compounds is preferably a compound in which the isocyanate group of the isocyanate compound has almost completely reacted with the above formula (I) compound, and unreacted The above-mentioned compound of formula [I] may be included. A reaction product of the compound represented by the above formula [I] and the above isocyanate compound having one or more active isocyanate groups in one molecule (hereinafter referred to as the reaction product) in a medium containing water as the main component. The concentration is usually in the range of 0.2 to 10% by weight. To dissolve the reactant in water, the reactant may be added to water and stirred, but in some cases, the reactant may be dissolved in a small amount of a water-soluble organic solvent such as acetone, alcoholic acid, or dioxane. After that, it may be added to water and stirred and dissolved. In addition, when the reactant is dissolved in a small amount of water-soluble organic solvent as described above, the concentration of the reactant is 15
It may be dissolved in water to a concentration of 60% by weight.

The reactant may be added at any step of emulsification.

Examples of the compounds (a) to (d) of the present invention include sodium propylnaphthalene sulfonate, sodium ethylnaphthalene sulfonate, sodium dimethylsulfosuccinate, sodium diethylsulfosuccinate, and ethylene oxide of octylphenol (hereinafter referred to as EO).
Examples include adducts (EO = 3 to 30 moles added), EO adducts of lauryl alcohol (EO = 3 to 30 moles added), and the like. These compounds can be used alone or in combination. The concentration of these compounds in a medium mainly composed of water is usually adjusted to a range of 0.1 to 3 times the weight. These compounds are added to water, stirred and dissolved.

The blocked polyisocyanate compound of the present invention is 1
It is a reaction product of a polyisocyanate compound having two or more isocyanate groups in the molecule and a compound having an active hydrogen atom in the molecule, and specific examples include hexamethylene diisocyanate, 2,4-tolylene diisocyanate, 2. 4-Chlorphenylene diisocyanate, 4.4
゛-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, ω.

Diisocyanates such as ω-1 (ditrimethylene thioether) diisocyanate, S-triazine triisocyanate, thiophosphoric acid tris(p-isocyanate phenyl) ester, triphenylmethane triisocyanate, diphenylmethane triisocyanate, butane-
1°2.2-)-diisocyanate, trimethylolpropane tolylene diisocyanate teradduct, 2.4.
Triisocyanates such as 4-diphenyl ether triisocyanate, polyisocyanate compounds such as polymethylene polyphenylisocyanate (including the case of crude diphenylmethane diisocyanate), and phenol;
Examples include phenols such as resol and thiophenol, lactams such as ε-caprolactam and valerolactam, oximes such as acetoxime and methyl ethyl ketoxime, and products reacted with ethyleneimine. The concentration of the blocked polyisocyanate compound in the emulsion is usually 10 to 50% by weight. Powderize the blocked polyisocyanate compound as necessary,
A well-known fine dispersion method by adding it to a medium containing water as the main component,
For example, the blocked polyisocyanate dispersion of the present invention can be obtained by emulsification using a ball mill, homogenizer, various media dispersers, or the like. Most of the particle diameters of the fine particles made of the blocked polyisocyanate compound in the blocked polyisocyanate dispersion of the present invention are 10 μm or less, and the average particle diameter is preferably in the range of 0.1 to 5.0 μm. .

The blocked polyisocyanate dispersion of the present invention may contain partially hydrolyzed ammonium of polyacrylic acid alkyl ester, hydroxyalkyl cellulose, etc., if necessary.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

In addition, each evaluation in Examples was performed by the following method.

(1) Phase separation after standing The niblocked polyisocyanate dispersion was placed in a test tube with an inner diameter of 16 mm and a length of 15 cm so that the liquid depth was 10 cm, the liquid was sealed with a silicone rubber stopper, and after being left for 2 months, the liquid The liquid depth of the transparent separation layer formed above the phase is expressed in mm, and the smaller the value, the better the storage stability.

(2) Thickness of fixed sediment after standing: Gently remove the blocked polyisocyanate dispersion liquid from the test tube after evaluating the phase separation after standing in the previous section (1), and deposit/fixed sediment layer at the bottom of the test tube. This is the deposition thickness expressed in mm, and the smaller the value, the better the storage stability.

(3) Foaming amount Niblocked polyisocyanate dispersion 4
Put 5 ml into a 100 ml graduated cylinder, and introduce air from the bottom of the graduated cylinder through a bubble-generating glass tube (inner diameter 6 mm, outer diameter 8 mm, with a glass filter at the tip) at 40 ml/min for 3 minutes. Check the amount of bubbles. Volume (m
It is expressed as l>. The smaller the value, the less bubbles are generated and the better.

Example 1. Comparative Example 1.2 EO-PO adduct of tristyrylphenol (x in the formula
=18. y=3>1 mole and isopropyl isocyanate 1
17 parts by weight of the reaction product with mole, 3 parts by weight of sodium dimethylsulfosuccinate, 200 parts by weight of methyl ethyl ketoxime block of 4,4-diphenylmethane diisocyanate, and 780 parts by weight of water were placed in a ball mill, and treated at 12 Orpm for 36 hours. Table 1 shows the storage stability (phase separation after standing and thickness of fixed sediment after standing) and foam height of the unblocked polyisocyanate dispersion obtained. For comparison, tristyrylphenol EO-PO
Example 1 except that the reaction product of the adduct (x=18.y=3>1 mole in the formula and 1 mole of isopropyl isocyanate was not added and the amount of sodium dimethylsulfosuccinate added was changed to 20 parts by weight) A blocked polyisocyanate dispersion similar to Example 1 (Comparative Example 1) and a blocked polyisocyanate dispersion similar to Example 1 except that sodium dimethylsulfosuccinate was not added (Comparative Example 2)
) evaluation results are shown in Table 1.

Table 1 shows that the blocked polyisocyanate dispersion of the present invention has excellent storage stability and little foaming.

Example 2 EO/PO of tristyrylphenol in Example 1
Instead of the reaction product of 1 mole of adduct (x = 18.y = 3 in the formula) and 1 mole of isopropyl isocyanate, 1 mole of EO adduct of distyrylphenol (x = 20 in the formula) and isocyanic acid. Using a reaction product with 1 mole of isopropyl,
Table 1 shows the evaluation results of the same blocked polyisocyanate dispersion as in Example 1 except that sodium propylnaphthalene sulfonate was used instead of sodium dimethylsulfosuccinate. From Table 1, the blocked polyisocyanate dispersion of the present invention has excellent storage stability;
It can be seen that there is little foaming.

Example 3 EO/PO of tristyrylphenol in Example 1
EO-PO adduct of monostyrylphenol (x=18.y=3 in the formula) instead of the adduct (x=18.y=3 in the formula).
Table 1 shows the evaluation results of the same blocked polyisocyanate dispersion as in Example 1 except that y=3) was used.

Table 1 shows that the blocked polyisocyanate dispersion of the present invention has excellent storage stability and little foaming.

Example 4.5 The use of an EO adduct of octylphenol (EO = 15 mol addition) in place of sodium dimethylsulfosuccinate in Example 1 (Example 4), an EO adduct of octyl alcohol (EO = 15 mol addition) ) was used (
Table 1 shows the evaluation results of the same blocked polyisocyanate dispersion as in Example 1 except for Example 5).

Table 1 shows that the blocked polyisocyanate dispersion of the present invention has excellent storage stability and little foaming.

Example 6.7 The methyl ethyl ketoxime block of 4,4-diphenylmethane diisocyanate in Example 1 was converted into 4.
4.4 Replacement of 4'-diphenylmethane diisocyanate with ε-caprolactam block (Example 6)
--Example 1 except that diphenylmethane diisocyanate was replaced with ethyleneimine block (Example 7)
The evaluation results of the same blocked polyisocyanate dispersion are shown in Table 1. Table 1 shows that the blocked polyisocyanate dispersion of the present invention has excellent storage stability and little foaming.

Example 8 EO/PO of tristyrylphenol in Example 1
Adduct (in the formula, x = 18. y = 3> 1 mol was replaced with 2 mol, and 1 mol of isopropyl isocyanate was replaced with 1 mol of hexamethylene diisocyanate, but the same blocked polyisocyanate dispersion as in Example 1) Evaluation results first
Shown in the table. Table 1 shows that the blocked polyisocyanate dispersion of the present invention has excellent storage stability and little foaming.

Table 1 (blank below) [Effects of the invention] The blocked polyisocyanate dispersion of the present invention has excellent storage stability, such as less separation, less sticking to the bottom of the container, and less sedimentation even when stored for a long period of time, and has excellent storage stability. Foaming is suppressed when mixed with other aqueous liquids and stirred, or during the squeezing process after being applied to woven or knitted fabrics, eliminating the need for antifoaming agents.
It is excellent as a varnish, etc.

Claims (1)

[Claims] A. A compound represented by the following general formula [I]▲There are mathematical formulas, chemical formulas, tables, etc.▼...[I] (However, x in the above formula [I] is an integer from 10 to 60. ,y
is an integer from 0 to 60, n is an integer from 1 to 3), and 1
A reaction product with an isocyanate compound having one or more active isocyanate groups in the molecule, and B. at least one selected from the following (a) to (d).
Species compound (a) alkali metal salt of alkylnaphthalene sulfonic acid (b) alkali metal salt of dialkyl sulfosuccinic acid (c) ethylene oxide adduct of alkylphenol (d) ethylene oxide adduct of higher alcohol, and C, the above [I] formula A blocked polyisocyanate dispersion liquid comprising: a polyisocyanate compound blocked with a compound having an active hydrogen other than the above, and the main component of the medium is water.