WO2014188589A1

WO2014188589A1 - Water-in-oil emulsion mold release agent for polyurethane foam molding

Info

Publication number: WO2014188589A1
Application number: PCT/JP2013/064493
Authority: WO
Inventors: 末信杉田; 邦博内村
Original assignee: 有限会社エスアコード
Priority date: 2013-05-24
Filing date: 2013-05-24
Publication date: 2014-11-27

Abstract

Provided is a water-in-oil (W/O) emulsion mold release agent which has excellent drying properties, low viscosity and excellent storage stability and is suitable for polyurethane foam molding. A water-in-oil emulsion mold release agent for polyurethane foam molding, which is obtained by emulsifying an aqueous phase and an oil phase using a nonionic surfactant, and wherein the aqueous phase contains sodium chloride and/or calcium chloride. It is preferable that this mold release agent contains air bubbles of a non-combustible gas having a size of 50 microns or less, said air bubbles serving to promote the drying properties and the like.

Description

Water-in-oil emulsion mold release agent for polyurethane foam molding

The present invention relates to a mold release agent used for molding a polyurethane foam. More specifically, the present invention relates to a water-in-oil (W / O) emulsion type release agent in which an aqueous phase is dispersed in an oil phase.

¡When a polyurethane foam is molded, a mold release agent is applied to the mold to prevent adhesion between the foam and the mold, improving workability and reducing the defective rate. In the molding of semi-rigid polyurethane foams such as armrests, headrests and crash pads, the mold temperature during curing is usually set to 20 to 60 ° C. As a mold release agent used for molding such a semi-rigid polyurethane foam, various waxes and a composition obtained by mixing or dispersing silicone or petrolatum or hydrocarbon oil alone or mixed in a low-boiling industrial gasoline or chlorinated solvent. Often used are solvent-based mold release agents. A highly elastic polyurethane foam (hereinafter abbreviated as HR foam) is usually produced by curing in a low temperature range to a medium temperature range (45 to 70 ° C.). As a mold release agent used for molding this HR foam, a solvent-type mold release agent in which various waxes are dispersed in an organic solvent is frequently used (see Patent Document 1).

In addition to solvent-based mold release agents other than those described above, water-in-oil (W / O) emulsions and oil-in-water (O / W) emulsion release agents are proposed as mold release agents for polyurethane foam molding. (See Patent Document 2). The water-in-oil emulsion release agent has less influence on the human body and the environment and is easier to maintain than the solvent-based release agent. In addition, water-in-oil emulsion release agents are superior in wettability compared to oil-in-water emulsion release agents, and are excellent in mold release properties and surface properties of molded products (low cell roughness). There is an advantage. However, conventional water-in-oil emulsion mold release agents are not sufficient in properties such as viscosity and drying properties when cured at mold temperatures ranging from room temperature to medium temperature, and mold release properties and molded products In view of the surface characteristics of the resin, it has not yet achieved the same performance as the solvent-based mold release agent.

JP 2004-34464 A JP 2010-58310 A

The present invention has been made in view of the current situation, and its purpose is a water-in-oil emulsion type water-in-oil emulsion mold release agent for polyurethane foam molding, which is superior to conventional configurations. It is to provide a product having the above characteristics.

As a result of diligent research under the above-mentioned objectives, the present inventors have used a nonionic surfactant as an emulsifier for a water-in-oil (W / O) emulsion mold release agent, and have a specific chlorination in the aqueous phase. It has been found that the properties as a release agent for molding polyurethane foam can be improved by dissolving the product, and the present invention has been completed.

That is, the present invention is a water-in-oil emulsion in which an aqueous phase and an oil phase are emulsified using a nonionic surfactant, wherein a chloride is dissolved in the aqueous phase, and the metal of the chloride is It is a water-in-oil emulsion release agent for polyurethane foam molding, which is at least one selected from sodium and calcium.

According to the present invention, it is possible to realize a water-in-oil emulsion mold release agent for molding polyurethane foam, which has a lower viscosity than conventional products and has excellent storage stability and drying properties.

Hereinafter, embodiments of the present invention will be described in detail.
The water-in-oil emulsion release agent for molding polyurethane foam of the present invention (hereinafter abbreviated as water-in-oil emulsion release agent) is an oil obtained by emulsifying a water phase and an oil phase using a nonionic surfactant. A water-in-water emulsion, wherein a chloride is dissolved in the aqueous phase, and the metal of the chloride is at least one selected from sodium and calcium.

The oil phase is mainly composed of a solvent, waxes, and the nonionic surfactant, but may contain other components as necessary.

As the solvent, both nonpolar solvents and polar solvents can be used. These may be used singly or in combination of two or more as long as they form a single phase. Since the polar solvent interacts with the nonionic surfactant by hydrogen bonding or the like, it has the effect of improving the storage stability of the emulsion. Therefore, in the present invention, it is preferable to use a nonpolar solvent mixed with a polar solvent as a solvent.

As the non-polar solvent, petroleum hydrocarbon solvents such as naphthenic, paraffinic, and isoparaffinic solvents can be used. Specifically, aliphatic saturated hydrocarbons such as dodecane, manufactured by ExxonMobil {Isopar, Exol} (All are registered trademarks) and other companies' products. These can be used alone or in combination of two or more.

Examples of the polar solvent include ester solvents, higher fatty acid solvents, ether solvents and the like. These can be used alone or in combination of two or more.

Examples of the ester solvent include methyl oleate, ethyl oleate, isopropyl oleate, butyl oleate, hexyl oleate, methyl linoleate, isobutyl linoleate, ethyl linoleate, butyl stearate, hexyl stearate, and isooctyl stearate. , Isobutyl isostearate, 2-octyldodecyl bivalate, soybean oil methyl, soybean oil isobutyl, tall oil methyl, tall oil isobutyl, diisopropyl adipate, diisopropyl sebacate, diethyl sebacate, propylene glycol monocaprate, tri-2-ethylhexane Examples include trimethylolpropane acid and glyceryl tri-2-ethylhexanoate.

Examples of the higher fatty acid solvents include isononanoic acid, isomyristic acid, hexadecanoic acid, isopalmitic acid, oleic acid, and isostearic acid.

Examples of the ether solvent include diethyl glycol monobutyl ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether, propylene glycol dibutyl ether and the like.

Examples of the waxes include non-polar waxes such as polyethylene wax or microcrystalline wax and paraffin wax having a melting point of 40 to 110 ° C. and 25 ° C. of 5 to 150, a weight average molecular weight of 500 to 1000, An ethylene / propylene copolymer wax having a melting point of 75 to 105 ° C. is preferred. If necessary, silicone oils may also be added and used. These can be used alone or in combination of two or more.

The waxes are preferably contained in a range of 0.01 to 20% by mass with respect to the total amount of the release agent.

The nonionic surfactant is not particularly limited, but for example, sorbitan higher fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate and the like. And fatty acid glycerides, polyglycerin fatty acid esters, fatty acid diglycerides, and ethylene oxide adducts such as higher alcohols, alkylphenols, and fatty acids.

Among the nonionic surfactants, sorbitan fatty acid esters that form a stable water-in-oil emulsion in a water-rich system are particularly preferred as the nonionic surfactant. The sorbitan fatty acid ester here means an esterified product of sorbitan and a fatty acid. The fatty acid is preferably a fatty acid having 8 to 24 carbon atoms, more preferably an oxy fatty acid.

The HLB of the nonionic surfactant is preferably 3 to 8 from the viewpoint of easily forming a water-in-oil emulsion, and more preferably 3 to 5 from the viewpoint of improving the dispersion stability.

In the present invention, the content of the nonionic surfactant is preferably 0.1 to 20% by mass in terms of the solid content weight ratio with respect to the total amount of the release agent. More preferably, it is 0.2 to 15% by mass, and still more preferably 0.3 to 12% by mass. When the content of the nonionic surfactant is less than 0.1% by mass, the water-in-oil emulsion may become unstable depending on the components. In addition, when the content of the nonionic surfactant exceeds 20% by mass, the viscosity increases depending on the type of the nonionic surfactant, which may not be suitable for polyurethane foam molding applications.

The oil phase can be prepared by, for example, supplying all components in a known disperser such as a ball mill in a batch or divided and dispersing the mixture, and passing it through a known filter such as a membrane filter, if desired. For example, by preparing a mixed solution in which a part of the solvent and the whole amount of the wax are uniformly mixed in advance and dispersing in a disperser, the remaining components are added to the dispersion and passed through a filter. Can be prepared.

The aqueous phase is constituted by dissolving chloride in water. In the present invention, as the chloride, at least one metal salt selected from sodium and calcium is used. By dissolving the chloride applied to the aqueous phase, the viscosity of the water-in-oil emulsion release agent can be reduced. If the viscosity of the release agent is lowered, the particles when sprayed onto the mold become smaller, and the release agent can be more uniformly applied to the surface of the mold, reducing the surface roughness of the molded product, and , Mold releasability can be improved.

Also, by drying the chloride in the aqueous phase, the drying property of the water-in-oil emulsion release agent can be improved. Since the mold release agent applied to the mold needs to be dried before molding, the release agent with higher drying property can shorten the working time. Surface roughness of the molded product due to moisture remaining is less likely to occur.

Also, the storage stability of the water-in-oil emulsion release agent can be improved by dissolving the chloride in the aqueous phase. Specifically, the water-in-oil emulsion is stable, and even when stored for a long time, the water phase and the oil phase do not separate. From the viewpoint of the effect of improving storage stability, the chloride is preferably a sodium salt, and particularly preferably sodium chloride. Sodium chloride is preferably dissolved in an aqueous phase in an amount of 0.01 to 5% by mass based on the total amount of the release agent.

The aqueous phase may further contain an electrolyte, a humectant, a fungicide, a preservative, a pH adjuster, a flame retardant, and the like as necessary.

It is preferable that the water-in-oil emulsion release agent of the present invention further contains bubbles having a non-combustible gas diameter of 50 microns or less (hereinafter referred to as microbubbles). In addition to the dissolution of the chloride in the aqueous phase, the viscosity of the release agent can be further reduced by incorporating microbubbles of non-combustible gas. In addition, it is possible to further improve the drying property and the storage stability. The microbubbles of incombustible gas can be mixed in the release agent by, for example, forcibly stirring while injecting the incombustible gas and shearing the bubbles to 50 microns or less during emulsification of the release agent.

The water-in-oil emulsion release agent of the present invention can be produced by mixing and emulsifying the above oil phase and water phase. The aqueous phase and the oil phase may be prepared separately in advance, and then the aqueous phase solution may be added to the oil phase solution to emulsify, or the components constituting the oil phase may be added to the aqueous phase collectively or individually. Thereafter, it may be emulsified. A known emulsifier such as a disper mixer or a homomixer can be used for the production. The particle size of the aqueous phase dispersed by emulsification preferably has a particle size distribution of 0.1 to 50 microns.

The polyurethane foam release agent of the present invention is preferably blended so that the oil phase is 33 to 50% by mass and the aqueous phase is 67 to 50% by mass. When the ratio of the water phase exceeds 67% by mass, it becomes difficult to form a water-in-oil emulsion. On the other hand, if the aqueous phase is 50% by mass or more, the release agent is difficult to burn and safety is increased. In general, when the ratio of the aqueous phase increases, the viscosity of the release agent tends to increase. Therefore, the blending ratio of both phases is 40 to 50% by mass of the oil phase and 60 to 50% by mass of the aqueous phase. It is particularly preferable to do this.

The viscosity at 25 ° C. of the water-in-oil emulsion release agent of the present invention is preferably set in the range of 3 to 300 mPa · s, more preferably set in the range of 50 to 250 mPa · s, and more preferably 100 to 200 mPa · s. A range of s is particularly preferable. If a viscosity is in the said range, a mold release agent can be appropriately apply | coated to a metal mold | die using the existing spray apparatus etc.

The viscosity of the water-in-oil emulsion release agent can be adjusted by changing the components of the oil phase and the ratio of the oil phase to the water phase. Here, in general, if the water phase ratio and the amount of the nonionic surfactant are reduced, the viscosity of the water-in-oil emulsion release agent can be reduced. The storage stability of the release agent tends to decrease due to a decrease in the amount of the ionic surfactant. On the other hand, in the present invention, by dissolving the specific chloride in the aqueous phase, the viscosity can be lowered and the storage stability can be improved, so that the storage stability of the release agent is impaired. The viscosity of the release agent can be adjusted appropriately.

The water-in-oil emulsion release agent of the present invention can be suitably used for molding a polyurethane foam in which the mold temperature during curing is from room temperature to medium temperature (20 to 70 ° C.). Examples of the polyurethane foam molded using the water-in-oil emulsion release agent of the present invention include rigid polyurethane foam, semi-rigid polyurethane foam, and highly elastic polyurethane foam.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to these examples.

<Examples 1 to 3>
The oil phase and the water phase are mixed in the oil phase having the composition shown in Table 1 while stirring the water phase component shown in Table 1 at 3,000 rpm for 5 minutes using a high-speed homogenizer (manufactured by Tokushu Kika Kogyo Co., Ltd.). Drip until the ratio shown in. Then, the stirring process which stirs for 5 minutes at 10,000 rpm is performed. The water-in-oil emulsion release agents of Examples 1 to 3, which are examples of the present invention, were prepared. In the stirring step, carbon dioxide microbubbles were mixed in the liquid by stirring while injecting carbon dioxide gas into the liquid to shear the bubbles.

<Example 4>
A water-in-oil emulsion release agent of Example 4, which is an example of the present invention, was prepared in the same manner as in Example 1 except that carbon dioxide microbubbles were not mixed in the stirring step. As shown in Table 1, Example 4 has the same composition as Example 1 except that the liquid does not contain carbon dioxide microbubbles.

<Comparative Examples 1 to 3>
The water-in-oil emulsion release agents of Comparative Examples 1 to 3 having the compositions shown in Table 1 were prepared in the same manner as in Examples 1 to 3, except that carbon dioxide microbubbles were not mixed in the stirring step. The compositions of Comparative Examples 1 to 3 are almost the same as the compositions of Examples 1 to 3 except that they do not contain chloride and carbon dioxide microbubbles.

In addition, the detail of each component of Table 1 is as follows.
Wax 1: Petrolite EP-700 Melting point 93 ° C .: Petrolite Co. Wax 2: Viver 260 Melting point 51 ° C .: Petrolite Co. Solvent: New Solvent A: JX Nippon Oil & Energy Corporation Nonionic surfactant: Monooleic acid Sorbitan (HLB4.3): Nikko Chemical Co., Ltd. Water-soluble solvent: Diethylene glycol monobutyl ether

<Evaluation Test 1>
For each of Examples 1 to 3 and Comparative Examples 1 to 3, viscosity, storage stability, and drying properties were evaluated by the following methods. The results are shown in Table 2.

(1) Evaluation of viscosity Each viscosity was measured using BII type rotational viscometer (made by Toki Sangyo Co., Ltd.).

(2) Evaluation of storage stability For each of Examples 1 to 3 and Comparative Examples 1 to 3, the sample was allowed to stand at room temperature after adjustment, and whether or not the aqueous phase had been separated was visually determined periodically. It evaluated according to.
×: Aqueous phase separated within several hours △: Aqueous phase separated within several hours to 1 day ○: Aqueous phase separated within 1 day to 3 months ◎: Stable for 3 months or more

(3) Evaluation of drying property Each of Examples 1 to 3 and Comparative Examples 1 to 3 was applied to a plate-like aluminum surface at 40 ° C. using a hand gun and completely dried visually. The number of seconds until determination was measured and evaluated according to the following criteria.
×: 60 seconds or more △: 30 seconds to less than 60 seconds ○: 10 seconds to less than 30 seconds ◎: Less than 10 seconds

As shown in Table 2, Comparative Examples 1 to 3 had a viscosity higher than that suitable for application to the mold, poor drying properties, and extremely poor storage stability. In contrast, Examples 1 to 3 have viscosities suitable for application to molds, are excellent in drying properties and storage stability, and have characteristics required for mold release agents for polyurethane foam molding. Was enough. As shown in Table 1, the difference between Example 1 and Comparative Example 1, Example 2 and Comparative Example 2, and Example 3 and Comparative Example 3 is whether or not they contain chloride and microbubbles. . Therefore, this result suggests that the chlorides and microbubbles contained in Examples 1 to 3 contribute to a decrease in the viscosity of the release agent and an improvement in storage stability and drying property.

Also, as shown in Table 2, Example 4 was lower in viscosity than Comparative Example 1 and was excellent in drying property and storage stability. On the other hand, compared with Example 1, Example 4 had a high viscosity and was inferior in terms of drying properties. As shown in Table 1, Example 4 is a composition in which sodium chloride is dissolved in the aqueous phase of Comparative Example 1, and Example 1 is a composition obtained by further adding carbon dioxide microbubbles to Example 4. . Therefore, this result shows that even in the absence of microbubbles, by dissolving sodium chloride in the aqueous phase, the viscosity of the water-in-oil emulsion release agent can be reduced, and storage stability and drying can be reduced. It suggests that it can improve the sex. In addition to the dissolution of sodium chloride in the aqueous phase, this result further reduced the viscosity of the water-in-oil emulsion release agent by adding microbubbles, and further improved the drying properties. Suggest to get.

<Examples 5 to 7>
In the same manner as in Example 1, water-in-oil emulsion release agents of Examples 5 to 7 which are examples of the present invention having the composition shown in Table 3 were prepared.

<Example 8>
A water-in-oil emulsion release agent of Example 8, which is an example of the present invention, was prepared in the same manner as in Example 1 except that carbon dioxide microbubbles were not mixed in the stirring step. As shown in Table 3, the composition of Example 8 is the same as that of Example 5 except that it does not contain carbon dioxide microbubbles.

<Comparative Examples 4 to 6>
According to a conventional method, release agents of Comparative Examples 4 to 6 having the compositions shown in Table 3 were prepared. These are conventionally used oil-in-water (O / W) emulsion release agents.

<Comparative Example 7>
According to a conventional method, a release agent of Comparative Example 7 having the composition shown in Table 3 was prepared. This is a solvent-based mold release agent in which wax is dispersed in a second petroleum solvent (boiling point 150 to 200 ° C.) and is currently used as a main product for molding HR foam.

In addition, the detail of each component of Table 3 is as follows.
Wax 1: Petrolite EP-700 Melting point 93 ° C .: Petrolite Corp. Wax 2: Viver 260 Melting point 51 ° C .: Petrolite Corp. Wax 3: Polywax 655, molecular weight 655, melting point 102 ° C. Petrolite Corp. Solvent: New Solvent A: JX Nikko Nisseki Energy Co., Ltd. Nonionic surfactant: Sorbitan monooleate (HLB4.3): Nikko Chemical Co., Ltd. Ionic surfactant: Stearic acid morpholine salt: Made by adding stearic acid and morpholine .
Water-soluble solvent: Diethylene glycol monobutyl ether

<Evaluation Test 2>
The following performance evaluation was performed on the compositions of Examples 5 to 8 and Comparative Examples 4 to 7. Test items and test methods are shown below, and the results are shown in Table 4.

(1) Application of release agent The temperature of an iron mold (180 mm x 250 mm x 30 mm) was adjusted to 55 ° C, and the solid content of the release agent was about 10 for each of Examples 5 to 8 and Comparative Examples 4 to 7. What was adjusted to be% was applied with about 20 g / m ² with an air gun and left to dry for about 60 seconds.

(2) Polyurethane foam molded urethane foam raw material Polyol component 100 parts by weight TDI-80 43 parts by weight The above urethane foam raw material is stirred at 1500 rpm for 10 seconds at room temperature, and then the release agent is applied as described above for 60 seconds. The reaction was completed by pouring into a dried mold (55 ° C.), closing the lid, and curing in an oven at 60 ° C. for 7 minutes.

(3) Evaluation of releasability The lid of the above mold was opened, the foam was manually pulled out from the mold, and the degree of resistance at the time of demolding was evaluated by the following evaluation method.
X: The foam is torn during demolding.
Δ: Heavy and partially sticking foam.
○: Although it is somewhat heavy, demolding is possible.
A: It can be removed smoothly without resistance.

(4) Evaluation of surface characteristics of molded product The surface roughness of the molded foam was visually observed and evaluated according to the following criteria.
X: A state in which many rough surfaces are generated or skin is generated.
Δ: Some parts are rough.
○: No cell roughness.

As shown in Table 4, in Examples 5 to 8, good results were obtained in both releasability and surface characteristics. This result shows that Examples 5 to 8 have sufficient characteristics as a release agent for molding polyurethane foam. In particular, Examples 5 to 7 containing microbubbles showed excellent results in both releasability and surface characteristics compared to Example 8 not containing microbubbles. This is considered to be due to the fact that the viscosity of the release agent is lowered and the drying property is improved by the action of the microbubbles.

On the other hand, as shown in Table 4, all of the oil-in-water emulsion release agents of Comparative Examples 4 to 6 had large resistance during demolding, and the surface roughness of the molded product was also severe. This is presumably because Comparative Examples 4 to 6 had poor drying properties, and a drying time of 60 seconds at a mold temperature of 55 ° C. was insufficient, and water droplets remained on the mold surface. In addition, the solvent-based mold release agent of Comparative Example 7 was heavy, and many surface roughness was confirmed in the molded product. This result is considered to be because, even in Comparative Example 7, the drying time of 60 seconds at the mold temperature of 55 ° C. is insufficient, and the solvent remains on the mold surface.

As is clear when Examples 5 to 8 and Comparative Examples 4 to 7 are compared, the results of Examples (Examples 5 to 8) of the present invention cannot be obtained with conventional products (Comparative Examples 4 to 7). Even under molding conditions, a good molded product can be obtained. This is considered to be because the drying properties of Examples 5 to 8 are remarkably good, and when applied to a 55 ° C. mold, they are dried in a short time. This suggests that the drying time of the release agent can be shortened by using the water-in-oil emulsion release agent of the present invention.

The water-in-oil emulsion mold release agent of the present invention has a low viscosity and excellent storage stability compared with existing water-in-oil emulsion mold release agents, and the drying property of the mold release agent is remarkably improved. Therefore, it is expected to be used for molding polyurethane foams such as semi-rigid polyurethane foams and HR foams, in which the mold temperature during curing is from room temperature to medium temperature. Since the water-in-oil emulsion release agent of the present invention has little influence on the human body and the environment and is easy to maintain, it can be used as a substitute for solvent-based release agents in the polyurethane foam molding field. It is expected to improve safety. In addition, in the HR foam molding field where a release agent having a second petroleum having poor drying property as a main solvent is used, the water-in-oil emulsion release agent of the present invention having excellent drying property is particularly useful. Is considered high.

Claims

A water-in-oil emulsion in which a water phase and an oil phase are emulsified using a nonionic surfactant,
Chloride is dissolved in the aqueous phase,
A water-in-oil emulsion mold release agent for molding polyurethane foam, wherein the chloride metal is at least one selected from sodium and calcium.
The water-in-oil emulsion mold release agent for molding polyurethane foam according to claim 1, wherein the chloride is a sodium salt.
The water-in-oil emulsion release agent for molding polyurethane foam according to claim 2, wherein the chloride is sodium chloride.
The water-in-oil emulsion mold release agent for polyurethane foam molding according to any one of claims 1 to 3, wherein the nonionic surfactant is a sorbitan fatty acid ester.
It consists of 33-50% by weight of oil phase and 67-50% by weight of water phase,
The water-in-oil emulsion release agent for molding polyurethane foam according to claim 4, wherein the sorbitan fatty acid ester is contained in the oil phase in an amount of 0.1 to 20% by mass based on the total amount of the release agent.
The water-in-oil emulsion mold release agent for molding polyurethane foam according to claim 4 or 5, wherein the sorbitan fatty acid ester is an esterified product of sorbitan and oxy fatty acid.
The water-in-oil emulsion release agent for molding polyurethane foam according to any one of claims 1 to 6, wherein the viscosity at 25 ° C is 3 to 300 mPa · s.
The water-in-oil emulsion mold release agent for molding polyurethane foam according to any one of claims 1 to 7, comprising bubbles of incombustible gas having a diameter of 50 microns or less.