JPS6172032A - Porous sheet material and its manufacturing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a porous polyurethane sheet material and a method for producing the same. The aim is to provide productivity.

(Prior Art) Many porous sheet materials made of polyurethane as natural leather substitutes and methods for producing them have been known, and can be roughly divided into wet methods and dry methods.

(Problem to be solved by the invention) Both methods have their advantages and disadvantages, and the dry method is superior in terms of productivity. As such a dry method, for example, the
There are methods described in Japanese Patent Laid-Open No. 18249 and Japanese Patent Application Laid-Open No. 51-41063, but these conventional methods use a relatively large amount of wood-loving polyurethane to form the polyurethane layer. The mechanical properties and physical/chemical properties are not sufficient, and the complicated and time-consuming drying process in the manufacturing method is a decisive drawback. In order to solve these drawbacks, it would be inevitable to reduce the amount of wood-philic polyurethane used, but it is clear that doing so would lead to other drawbacks (for example, instability of the treatment solution, etc.). It has become.

As a result of intensive research in order to solve the above-mentioned drawbacks of the prior art, the present inventor has made a hydrophobic polyurethane dispersion or solution based on a specific manufacturing method the main component of the coating forming material, and on the other hand,
The present invention was completed based on the finding that the above-mentioned drawbacks of the prior art can be solved by using a small amount of hydrophilic modified polyurethane obtained by graft polymerizing a specific proportion of an addition-polymerizable monomer containing hydroxyl groups as an emulsifier. .

(Means for Solving the Problems) That is, the present invention provides a porous sheet material in which a porous layer comprising a hydrophobic polyurethane (a) and a hydrophilic modified polyurethane (b) is provided on a base material; (a) is a hydrophobic polyurethane obtained by reacting a hydrophobic polyol, an organic diisocyanate, and a chain extender;
) is a polyurethane obtained by reacting a hydrophobic polyol and an organic diisocyanate in the presence of a chain extender having an unsaturated double bond, and then graft polymerizing an addition polymerizable monomer containing a hydroxyl group, The porous sheet material and its manufacturing method are characterized in that the hydrophilic modified polyurethane (b) contains 10 to 50% by weight of a hydrophilic addition-polymerizable monomer polymer.

To explain the present invention in more detail, the hydrophobic polyurethane (a) used in the method of the present invention itself is a conceptually known material, and is obtained by reacting a hydrophobic polyol, an organic diisocyanate, and a chain extender. Examples of hydrophobic polyols include polyethylene adipate, polyethylene propylene adipate, polyethylene butylene 7-dipate, polyethylene adipate, polybutylene adipate, and polyethylene succinate having a hydroxyl group at the end and a molecular weight of 300 to 4,000. , polybutylene succinate, polyethylene sepacate, polybutylene sebacate, polytetramethylene ether glycol, poly-ε-caprolactone diol, polyhexamethylene adipate, carbonate polyol, polypropylene glycol, etc. Organic diisocyanates include 4, 4'-diphenylmethane diisocyanate (MDI), water-added MDI, inphorone diisocyanate, 1,3-xylylene diisocyanate, 1,4-
xylylene diisocyanate, 2.4-)lylene diisocyanate, 2.6-lylene diisocyanate, 1,
There are 5-naphthalene diisocyanate, m-phenylene diisocyanate, P-phenylene diisocyanate, etc., and chain extenders include ethylene glycol, propylene glycol, diethylene glycol, -1,4-butanediol, 1,6-hexanediol, ethylenediamine, 1.2-propylene diamine, trimethylene diamine, tetramethylene diamine, hexamethylene diamine, decamethylene diamine, inphoron diamine, m-
Examples include xylylene diamine, hydrazine, and water.

The hydrophobic polyurethane dispersion or solution (e) contains polyurethane (a) in an organic solvent (a) which has limited mutual solubility with water and preferably has a boiling point of 120°C or less at normal pressure.
It can be obtained by reacting the above three components in e). The reaction conditions, such as temperature and time, may be conventionally known conditions.

Preferred organic solvents (c) include methyl ethyl ketone, methyl-n-propyl ketone, methyl isobutyl ketone, diethyl ketone, methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, butyl acetate, and acetone. , cyclohexane, tetrahydrofuran, dioxane, methanol, ethanol, isopropyl alcohol, butanol, toluene, xylene,
Dimethylformamide, dimethyl sulfoxide, perchlorethylene, trichlorethylene, methyl cellosolve, butyl cellosolve, cellosolve acetate, etc. can also be used. Among these organic solvents, those that have limited mutual solubility with water or those that do not dissolve at all are mixed with other solvents.

Of course, a solvent of 0 or more, which is used with a limit to its mutual solubility with water, can also be used as a mixed solvent. By preparing polyurethane (a) in such an organic solvent, a dispersion or solution (e) is obtained, the solids content of which can be reduced by addition or removal of the same or other solvents from about 5 to 50%.
A range of 60% by weight is convenient.

The modified polyurethane (b) used in the present invention is an addition-polymerizable monomer graft polymer containing hydroxyl groups.
Such a modified polyurethane (b), which may contain 0 to 50% by weight and be dissolved in an organic solvent (e), is capable of bonding the hydrophobic polyol and the organic diisocyanate to an unsaturated double bond. It is obtained by reacting in the same manner as polyurethane (a) in the presence of a chain extender, and then graft polymerizing a hydrophilic addition-polymerizable monomer. The above-mentioned chain extender to be used is such that part or all of the chain extender has an average molecular weight of about 1 obtained by dehydration condensation of an unsaturated dibasic acid and a bifunctional compound having active hydrogen.
It is preferable to use an unsaturated compound having active hydrogen at both ends of 40-1,000 (hereinafter referred to as a specific chain extender), and this specific chain extender includes itaconic acid, fumaric acid, maleic anhydride, citracon. Unsaturated dibasic acids such as acids or their functional derivatives, diamines such as hydrazine, ethylenediamine, piperazine, propylene diamine, xylylene diamine, inphorondiamine, ethylene glycol, 1,4-butanediol, 1.3 - Glycols such as butanediol, 2,3-butanediol, propylene glycol, diethylene glycol, 1,5-bentanediol, neopentyl glycol, dipropylene glycol, amine alcohols such as monoethanolamine, dimethylethanolamine, etc. It is obtained by polycondensation with a difunctional compound having active hydrogen at a ratio of about 1.2 to 2.0 moles per mole of unsaturated dibasic acid, and particularly preferred ones have an average molecular weight of about 140 to 1.000. This polycondensation reaction itself may be carried out by a conventionally known method, for example, in an inert gas atmosphere at a reaction temperature of 150 to 240°C in the presence of a catalyst such as a sulfonate compound or a titanate compound for about 3 to 15 hours. It's convenient. Such a specific chain extender is used in the method of the present invention in an amount of o per mole of hydrophobic polyol.
, ooi to 0.5 mole.

This particular chain extender is also compatible with other common chain extenders,
For example, it can be used in combination with water or a bifunctional compound containing active hydrogen as described above.

The addition-polymerizable monomer containing a hydroxyl group used in the present invention may be any known one, such as 2-hydroxy-ethyl, 2- Hydroxypropyl esters are preferred.

In addition, to adjust the balance between hydrophilicity and hydrophobicity, it may be used in combination with other addition-polymerizable seven polymers. For example, acrylic acid, α-chloroacrylic acid, methacrylic acid, methyl, ethyl, propyl, Butyl ester; styrene, methylstyrene, dimethylstyrene, ethylstyrene, methoxystyrene, divinylbenzene, α-methylstyrene, β-methylstyrene, chlorstyrene, 2.
5-dichlorostyrene, α-chlorostyrene or derivatives thereof are preferred.

In addition, in order to increase the stability of the polyurethane emulsion (d),
It is also possible to use the modified polyurethane (b) in combination with a general W2O type emulsifier.

The above-mentioned modified polyurethane (b) can be used as a solution in an organic solvent or alone, as a polyurethane dispersion or solution (b).
e).

In this mixed dispersion or solution, polyurethane (a) is in a dispersed state or solution, and modified polyurethane (b)
is in a dissolved state, and the total solid content is about 5 to 60% by weight.

The polyurethane emulsion (d) used in the present invention is prepared by stirring the above-mentioned mixed dispersion or solution and adding a saturated amount of water or less to the mixture, for example, 100% by weight of solids in the mixed dispersion or solution. It is obtained by adding about 50 to 500 parts by weight of water per part. The emulsion thus obtained is a milky white creamy fluid and remains stable even if left as is for several months. Such emulsions may contain various additives, such as colorants, as required.
Known additives such as crosslinking agents, stabilizers, fillers, etc. can be optionally added.

The base material used in the present invention may be any base material such as various woven fabrics, knitted fabrics, non-woven fabrics, release papers, plastic films, metal plates, glass plates, etc. The application method may be any known method such as a coating method, a dipping method, or a combination of these methods.
The amount of application and/or impregnation is approximately 5-2.000g
(compounded liquid)/rr+', it can be varied within a wide range depending on the purpose.

The drying step in the method of the present invention can be completed in a very short time and without the need for complicated processing, and this drying process is the rate-limiting step in productivity in the dry method as in the method of the present invention. Therefore, such a short drying time is extremely advantageous compared to conventional methods. That is, the coated and/or impregnated substrate is
There is no need for any coagulation process as described in Publication No. 3, and approximately 6
0-100℃ for about 1-3 minutes and about 100-150℃
The desired porous sheet material of the present invention can be obtained by only drying for about 1 to 3 minutes. The reason why such a short drying time is achieved is that the hydrophobic polyurethane (a) used as a film forming agent in the present invention accounts for the majority of the total polyurethane, and a small amount of the surfactant (polyurethane (b
)), it is stably dispersed and emulsified with water, and during drying, it quickly and easily comes into contact with water due to evaporation of the organic solvent, resulting in gelation.

(Function/Effect) The porous sheet material obtained by the present invention as described above has a very fine pore structure, has excellent physical properties, and has excellent water vapor permeability, and can be used for various synthetic leathers, etc. It is useful as a material for clothing, shoes, waterproof cloth, tents, wallpaper, flooring materials, filtration materials, filters for air conditioners, etc.

Next, the present invention will be specifically explained with reference to Examples. In addition,
All numbers in the middle of the text or percentages are based on weight.

Examples 1 to 7 (Production of hydrophobic and woody polyurethane) 1. Polytetramethylene glycol (average molecular weight about i
, ooo, hydroxyl value 112) 1,000 parts, ethylene glycol 93 parts, diphenylmethane diisocyanate 6
Add 25g to 1.500 parts of methyl ethyl ketone,
After reacting at 0°C for 8 hours, 2,500 parts of methyl ethyl ketone was added, and the mixture was cooled to room temperature with stirring to reduce the solid content to 3.
A 0% milky white polyurethane dispersion (1) was obtained.

2.1.4-Butaneethylene adipate (average molecular weight approximately 1,000, hydroxyl value 112) 1,000 parts, 1,4-
144 parts of butanediol, 1.14 parts of methyl ethyl ketone
After reacting 4 parts and 650 parts of diphenylmethane diisocyanate at 70°C for 8 hours, 3.042 parts of methyl ethyl ketone was added to homogenize the mixture, and the mixture was cooled to room temperature with stirring to form a milky white polyurethane dispersion with a solid content of 30% (2
) was obtained.

3.1.6-hexamethylene adipate (average molecular weight 2
．． 000, hydroxyl value 56) 1,000 parts, 125 parts of 1,4-butanediol, and 472 parts of diphenylmethane diisocyanate were added to 1,200 parts of methyl ethyl ketone, and after reacting at 70°C for 8 hours, an additional 2.526 parts of methyl ethyl ketone was added. Add it, homogenize it, cool it to room temperature while stirring, and prepare a milky white polyurethane dispersion (30% solids).
) was obtained.

4.1. After reacting 1,000 parts of 4-butane ethylene adipate (average molecular weight about 1,000, hydroxyl value 112) and 408 parts of isophorone diisocyanate at 100°C for 6 hours, 1.230 parts of methyl ethyl ketone, )le z71,23
Add 0 parts, 1.230 parts of n-butanol, and 148 parts of isophoronediamine, stir well to homogenize, and reduce the solid content to 3.
A 0% polyurethane solution (4) was obtained.

5. 100 parts of itaconic acid and 95 parts of ethylene glycol were placed in a reaction vessel equipped with a dehydrator, stirred while blowing nitrogen gas, and heated to 140°C. Thereafter, the temperature was raised to 200°C while increasing the temperature by 30°C every hour. The dehydration polycondensation reaction was continued at that temperature, and the reaction was terminated when the acid value became 1 or less. The resulting unsaturated compound having active hydrogen at both ends had an acid value of 0.5. The average molecular weight was 220.

Next, 100 parts of polytetramethylene glycol ether (average molecular weight approximately 2,000, hydroxyl value 56), 3 parts of the unsaturated compound having active hydrogen at both ends obtained by the above reaction, 16 parts of 4.4"-diphenylmethane diisocyanate 100 parts of methyl ethyl ketone was placed in a reaction vessel and reacted at 75 to 85°C under a nitrogen stream. As the viscosity increased, it was diluted with methyl ethyl ketone to finally form a polyurethane resin solution with a resin concentration of 30% and a viscosity of 12.000 cpS/20°C. Obtained.

Next, 100 parts of this polyurethane resin solution was added with 5 parts of n-butyl methacrylate, 10 parts of 2-hydroxyethyl methacrylate, 25 parts of methyl ethyl ketone, 40 parts of sec-butyl alcohol, and 0 parts of benzoyl peroxide.
．． 2 parts and reacted for 6 hours at 80-85°C in a nitrogen atmosphere, resulting in a viscosity of 2,000 cps/25°C and a solid content of 25
% modified polyurethane resin solution (5) was obtained.

6. 100 parts of polyethylene glycol adipate glycol (average molecular weight approximately 1,000, hydroxyl value 112), 4 parts of the unsaturated compound having active hydrogen at both ends obtained in Example 5, 30 parts of 4,4'-diphenylmethane diisocyanate and 100 parts of methyl ethyl ketone were placed in a reaction vessel and reacted at 75 to 85°C under a nitrogen stream, and diluted with methyl ethyl ketone as the viscosity increased to obtain a final polyurethane resin solution with a resin concentration of 30% and a viscosity of 8,0OOcps/20°C. Ta.

Next, 5 parts of methyl methacrylate, 15 parts of 2-hydroxypropyl methacrylate, 45 parts of methyl ethyl ketone, 50 parts of isopropyl alcohol, and 0.0 parts of benzoyl peroxide are added to 100 parts of this polyurethane resin solution.
2 parts were added and reacted for 6 hours at 80-85°C in a nitrogen atmosphere, resulting in a viscosity of 1.500 cps/25°C and a solid content of 25%.
A modified polyurethane resin solution (6) was obtained.

7. 100 parts of itaconic acid and 1,4-butanediol 13
8 parts were placed in a reaction vessel equipped with a dehydrator, stirred while blowing nitrogen gas, and heated to 140°C. Thereafter, the temperature was raised to 200°C while increasing the temperature by 30°C every hour. The dehydration polycondensation reaction was continued at that temperature, and the reaction was terminated when the acid value became 1 or less.

The resulting unsaturated compound having active hydrogen at both ends had an acid value of 0.4 and an average molecular weight of 280. First, polytetramethylene glycol 21ter (average molecular weight approximately 2.0
00, hydroxyl value 56), 4 parts of the unsaturated compound having active hydrogen at both ends obtained by the above reaction, 17 parts of hydrogenated 4°4'-diphenylmethane diisocyanate, and 100 parts of methyl ethyl ketone were placed in a reaction vessel.
While carrying out the reaction at 80 to 85°C in a nitrogen atmosphere, 0.1 part of dibutyltin dilaurate was added, and as the viscosity increased, it was diluted with MEK until the resin concentration was 30% and the viscosity was 2.
, OOOc ps/20°C polyurethane resin solution was obtained.

Next, 10 parts of ethyl methacrylate, 10 parts of 2-hydroxyethyl acrylate, 65 parts of methyl ethyl ketone, 15 parts of inpropyl alcohol, and 0.4 parts of azobisisobutyronitrile were added to 100 parts of this polyurethane resin solution. .

The reaction was carried out in a nitrogen atmosphere at 80 to 85°C for 7 hours to obtain a modified polyurethane resin solution (7) with a viscosity of 600 cps/25°C and a solid content of 25%.

Examples 8 to 13 (Production of polyurethane emulsion) Example 1
The following polyurethane V10 emulsion was prepared by stirring the products of ~7, organic solvent, and water in a homomixer.

8. Polyurethane, 8) Polyurethane dispersion (1) 100 parts Polyurethane solution (5) 10 parts Methyl ethyl ketone 20 parts Toluene
20 parts water
80 parts 9, polyurethane 9
) Polyurethane dispersion (2) 100 parts Polyurethane solution (5) 72 parts Dioxa 7
10 parts toluene
10 parts xylene 20
Department water
60 parts 10, polyurethane 10) Polyurethane dispersion (2) 100 parts polyurethane solution (6) 7 parts methyl ethyl ketone 20 parts Kijirol
20 parts water
75 parts 11, polyurethane 1
1) Polyurethane dispersion (3) 100 parts Polyurethane solution (6) 5 parts tetrahydrofuran 20 parts xylene
20 parts water
80 parts 12, polyurethane 12
) Polyurethane dispersion (-3) 100 parts Polyurethane solution (7) 12 parts Methyl ethyl ketone 150 parts Methyl isobutyl ketone
20 parts water
70 parts 13, polyurethane
13) Polyurethane solution (4) 100 parts Polyurethane solution (5) 10 parts calcium carbonate
10 parts toluene
30 parts methyl ethyl ketone 2
0 parts water
80 parts of the above polyurethane emulsion (8) to (13)
) are shown in Table 1 below.

1st L rinj milk 1 ΣΩ 1 凰 8 2
0.000(cps) 14.1(:)8
14.000 15.610
25.000 14.311 23
．． 000 13.912 12
OL4 13 31.000 1? , 0 equipment
Stability: No change after 1 month or more Examples 14 to 20 The polyurethane emulsions (8) to (13) shown in Table 1 above were applied (or impregnated) to various base materials, dried and A porous sheet material of the present invention was obtained.

, 2' Example 14 L-cross-8LJt Release paper '1 m'' 200 (coating) tJLJJ! 80℃ 2 minutes + 125℃ 2 minutes Example 15 L-cross-85-j Nylon tack, m'' 600 (coating) )10
180°C 2 minutes + 125°C 2 minutes Example 16 Milk” L solution - 9 □ Cotton cloth ° Cloth rr1'400 (coating) 1ro 4
80°C 2 minutes + 125°C 2 minutes Example 17 Breast L-10LJi T/R raised cloth °・cloth rr
r'' 800 (application) 1u'' 80℃ 3 minutes + 140℃
3 minutes Example 18 9" 1 scoop - Hydrophobic [] Cotton Cloth '-rn' 300 (coating) Illusion u" 80℃ 2 minutes + 125℃ 2 minutes Example 19 9'' 1 scoop - 12 tut Non-woven fabric'・Go 1000 (Impregnation) 10
” 90°C 3 minutes + 140” 03 minutes Example 20 15-13 tut Tetron Tack rrI 10
0 (Application) Side port u 80℃ 2 minutes + 125℃ 2 minutes 1, 3 1 sheet 1 and JI Dan concave N14 White 0.475 72 8230 Uniform dense 15
// 0.625 171 5950 /
118 // 0.527 110 8280
tt17 // 0.873 225
5140 tt18 // 0J
38 78 5140 //19”
-3980tt 20 tt O, 822585B20
tt Notes ■... Apparent specific gravity (g/c) ■... Thickness) III ・min degrees (g/rn' -24h) (J
IS ZO208B) ■... Internal pore structure As described above, according to the method of the present invention, a porous sheet material with excellent physical properties can be obtained in an extremely short drying process.

Patent applicant: Dainichiseika Industrial Co., Ltd. (1 other person)

Claims (3)

[Claims] (1) In a porous sheet material in which a porous layer consisting of a hydrophobic polyurethane (a) and a hydrophilic modified polyurethane (b) is provided on a base material; the above hydrophobic polyurethane (a)
is a hydrophobic polyurethane obtained by reacting a hydrophobic polyol, an organic diisocyanate, and a chain extender. This is a polyurethane obtained by reacting in the presence of a chain extender having a chain extender, and then graft polymerizing a hydroxyl group-containing addition polymerizable monomer, wherein the hydrophilic modified polyurethane (b) has a hydrophilic addition polymerizable monomer. A porous sheet material containing 10 to 50% by weight of a monomer polymer. (2) A water-in-oil polyurethane emulsion (d) consisting of a hydrophobic polyurethane (a), a hydrophilic modified polyurethane (b), an organic solvent (c) and water is impregnated and/or applied to a substrate. In a method for producing a porous sheet material, the hydrophobic polyurethane (a) comprises:
A hydrophobic polyurethane dispersion or solution (e) obtained by reacting a hydrophobic polyol, an organic diisocyanate, and a chain extender in an organic solvent (c) having limited mutual solubility with water; Modified polyurethane (
b) reacts a hydrophobic polyol and an organic diisocyanate in the presence of a chain extender having an unsaturated double bond;
Then, an addition polymerizable monomer containing a hydroxyl group is graft-polymerized, and the hydrophilic modified polyurethane (b) contains 10 to 50% by weight of the hydrophilic addition polymerizable monomer. A method for producing a porous sheet material. (3) A chain extender having an unsaturated double bond is attached to both ends with an average molecular weight of approximately 140 to 1,000 obtained by dehydration condensation of an unsaturated dibasic acid and a bifunctional compound having active hydrogen. The manufacturing method according to claim (2), which comprises an unsaturated compound having active hydrogen.