JP2019014222A - Mold release agent composition, method for forming mold release film, and coating device - Google Patents

Abstract

To provide a mold release agent composition capable of providing satisfactory releasability to an object even by spray coating with use of carbon dioxide.SOLUTION: Provided is a mold release agent composition containing a release agent, containing a wax and a solvent, and liquid carbon dioxide. The solvent is liquid at 20°C and 1 atm. The solvent contains a solvent with a solubility parameter of 17.5 MPaor less. The liquid carbon dioxide has a density of 700 kg/mor more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a release agent composition containing carbon dioxide.

  As a method for imparting releasability to an object, a release component such as wax is mixed with liquid carbon dioxide, and the obtained release agent composition is sprayed onto the object to release the release component on the surface of the object. A method of coating a layer is known (for example, Patent Document 1). In this method, liquid carbon dioxide functions as a diluent, and the viscosity of the release agent composition is lowered to a level at which spraying can be performed, so that spraying can be suitably performed.

Special table 2008-540078

  However, even when a conventional release agent composition containing liquid carbon dioxide is sprayed on an object, the release property by the release agent may not be sufficiently exhibited.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a release agent composition or the like that can impart sufficient releasability to an object even by spraying with carbon dioxide. To do.

  As a result of intensive studies by the present inventors, if the release agent composition contains a release agent containing a wax and a specific solvent and liquid carbon dioxide in a specific density range, spray coating using carbon dioxide is performed. As a result, it has been found that sufficient releasability can be imparted to the object, and the present invention has been completed.

A release agent composition according to an embodiment of the present invention includes a release agent containing a wax and a solvent, and liquid carbon dioxide. The solvent is a liquid at 20 ° C. and 1 atm, and the solvent has a solubility. The parameter contains 17.5 (MPa) ^0.5 or less solvent, and the liquid carbon dioxide has a density of 700 kg / m ³ or more.

Solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less is selected from the group consisting of aliphatic hydrocarbons, gasoline, kerosene, coal tar naphtha, petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, and mineral spirits. May be a weak solvent.

  The melting point of the wax may be 30-140 ° C.

  The wax may be a polyethylene wax or a synthetic hydrocarbon wax.

  The compounding quantity of a wax may be 0.1-40 mass% with respect to the mold release agent whole quantity.

  A method for forming a release film according to an aspect of the present invention includes a step of spraying the release agent composition from a nozzle to form a release agent liquid film on an object, and drying the release agent liquid film. And forming a release film.

A coating apparatus for a release agent composition according to an aspect of the present invention includes a release agent composition preparation unit that prepares a release agent composition, and a spray nozzle that sprays the prepared release agent composition. The release agent composition includes a release agent containing a wax and a solvent and liquid carbon dioxide, the solvent is liquid at 20 ° C. and 1 atm, and the solvent has a solubility parameter of 17.5. (MPa) The liquid carbon dioxide contains a solvent of ^0.5 or less, and has a density of 700 kg / m ³ or more.

  According to the present invention, sufficient releasability can be imparted to an object even by spray coating using carbon dioxide.

It is a block diagram which shows the structure of a continuous mixing type carbon dioxide coating apparatus.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

  A release agent composition according to an embodiment of the present invention includes a release agent containing a wax and a solvent, and liquid carbon dioxide.

<Release agent>
The release agent contains a wax and a solvent. The wax is usually not completely dissolved in the solvent and is dispersed in the solvent.

<Wax>
Wax is a mold release component which usually has a melting point of 30 to 140 ° C. and has an effect of imparting mold release properties to an object. As waxes, natural waxes such as paraffin wax, microcrystalline wax, montan wax, carnauba wax, semi-synthetic waxes such as amide wax, polyethylene wax, polypropylene wax, polyethylene polypropylene copolymer wax, Fischer-Tropsch wax, and other hydrocarbons Synthetic waxes such as synthetic waxes may be mentioned. One type of wax may be used alone, or two or more types may be used in combination.

  The wax may have a melting point of 30 ° C or higher, 60 ° C or higher, or 70 ° C or higher, and may be 140 ° C or lower, 120 ° C or lower, or 100 ° C or lower. The weight average molecular weight of the wax may be 300 or more, 600 or more, or 700 or more, and may be 3000 or less, 900 or less, or 800 or less. The weight average molecular weight of the wax is measured by the GPC method.

  The blending amount of the wax is 0.1% by mass or more, 3% by mass or more, 5% by mass or more, 8% by mass or more, 10% by mass or more, or 15% by mass or more with respect to the total amount of the release agent. It may be 40% by mass or less, 30% by mass or less, or 20% by mass or less.

<Solvent>
The solvent is liquid at 20 ° C. and 1 atmosphere. The solvent may be a single solvent or a mixed solvent, but the solvent contains at least one solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less. From the viewpoint of compatibility with liquid carbon dioxide, the solvent preferably has a solubility parameter of 12 to 17 (MPa) ^0.5 , 13 to 16.5 (MPa) ^0.5 , or 14 to 16 (MPa). ^At least one solvent of ^0.5 is included. In the present specification, the solubility parameter is a solubility parameter of Hildebrand. The solubility parameter (hereinafter referred to as SP value) is a thermodynamic parameter representing a measure of affinity between substances, and it is known that substances having similar SP values tend to be easily dissolved. ing. In this specification, unless otherwise specified, the SP value is the SP value at 20 ° C. and 1 atmosphere.

Examples of solvents having an SP value of 17.5 (MPa) ^0.5 or less include aliphatic hydrocarbons, gasoline (about 16), kerosene (about 16), coal tar naphtha (about 16), petroleum ether (about 16). Petroleum naphtha (about 16), petroleum benzine (about 16), turpentine oil (about 16), and mineral spirits (16.0). The numbers in parentheses are typical SP values for each solvent, and the unit is (MPa) ^0.5 . These solvents have low solvency and are sometimes referred to as “weak solvents”. Here, the petroleum naphtha and the coal tar naphtha each include an aromatic solvent naphtha in addition to the aliphatic one. The mineral spirit includes mineral thinner, petroleum spirit, white spirit, and mineral terpenes.

Aliphatic hydrocarbons are alkanes that can be represented by the general formula C _n H _{2n + 2} , such as pentane or hexane, alkenes having a double bond, alkynes having a triple bond, or cycloalkanes having a ring structure, cycloalkenes or cyclohexanes. Any of alkynes may be used. The aliphatic hydrocarbon has an SP value of 17.5 (MPa) ^0.5 or less. Specific examples of the aliphatic hydrocarbon include n-pentane (14.3), n-hexane (14.9), n-octane (15.5), cyclohexane (16.8), n-pentene (14.5). ), N-hexene (15.0), n-octene (15.5), cyclopentene (17.2), or cyclohexene (17.3).

  The weak solvents listed above are preferred as solvents because they have little influence on workers and the environment. Among these weak solvents, gasoline, kerosene, coal tar naphtha, petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, and mineral spirits are classified as “type 3 Classified as “solvent”. The third type organic solvent is preferable as a solvent because it has a particularly small influence on workers.

  Commercially available weak solvents include, for example, “Swazol 1000 (Petroleum Naphtha (Solvent Naphtha))” and “Swazol 1500 (Petroleum Naphtha (Solvent Naphtha))” (both manufactured by Maruzen Petroleum Corporation), “Solvesso 150 (Oil) Naphtha (solvent naphtha) "," solvesso 200 (petroleum naphtha (solvent naphtha)) "," HAWS (mineral spirit / petroleum ether) "and" LAWS (mineral spirit / petroleum ether) "(all manufactured by Shell Japan) , “Essonaphtha No. 6 (petroleum naphtha)”, “Exol D30, D40, D60, D80, D110 (petroleum naphtha)” and “Pegasol 3040 (kerosene)” (all manufactured by ExxonMobil Chemical Co., Ltd.), “A Solvent ( Mineral Spirit), Clensol (mineral "Pilit)" and "Ipsol 100 (Petroleum Naphtha)" (all made by Idemitsu Kosan Co., Ltd.), "Mineral Spirit A (Mineral Spirit)" and "Hyallom 2S (Petroleum Naphtha)" (both made by Nippon Petrochemical Co., Ltd.) ), “Linearene 10 (Petroleum naphtha)” and “Linearene 12 (Petroleum naphtha)” (both made by Idemitsu Petrochemical Co., Ltd.), “Ricasolve 900 (hydrogenated petroleum naphtha)”, “Ricasolve 910B (hydrogenated petroleum) Naphtha) ”and“ Ricasolve 1000 (hydrogenated petroleum naphtha) ”(both manufactured by Shin Nippon Chemical Co., Ltd.).

Other examples of solvents having an SP value of 17.5 (MPa) ^0.5 or less include ethyl ether (14.9), isobutyl acetate (17), isopropyl acetate (17.2), isopentyl acetate (isoamyl acetate, 16 0.0), acetic acid-n-butyl (17.4), acetic acid-n-pentyl (17.4), 1,1,1-trichloroethane (17.5), methyl isobutyl ketone (17.2), and Methyl-n-butyl ketone (17.0). The numbers in parentheses are typical SP values for each solvent, and the unit is (MPa) ^0.5 .

The lower limit amount of the solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less in all the solvents is not particularly limited, and is 1% by mass, 2% by mass, 3% by mass, 4% by mass, 5% by mass, Or it may be 6 mass%. In addition, the upper limit amount of the solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less in the total solvent is not particularly limited, and may be 100% by mass, or 90% by mass or 80% by mass.

From the viewpoint of environmental consideration, it is preferable that the amount of the weak solvent to be a total solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less is larger, 50 mass% or more, 60 mass% or more, 70 mass% or more, It can be 80 mass% or more, or 90 mass% or more. When the ratio of the weak solvent in the total solvent is high, the influence on the worker and the environment can be further reduced.

<Solvent with SP value exceeding 17.5 (MPa) ^0.5 >
The solvent may further contain one or more solvents having an SP value greater than 17.5 (MPa) ^0.5 . Examples of solvents having an SP value exceeding 17.5 (MPa) ^0.5 are acetone (20.3), isobutyl alcohol (22.7), isopentyl alcohol (isoamyl alcohol, 21.3), ethylene glycol monoethyl Ether (cellosolve, 21.5), ethylene glycol monoethyl ether acetate (cellosolve acetate, 19.3), ethylene glycol mono-n-butyl ether (butyl cellosolve, 19.4), ethylene glycol monomethyl ether (methyl cellosolve, 23.3) ), Ortho-dichlorobenzene (20.5), cresol (20.9), chlorobenzene (19.6), ethyl acetate (18.6), methyl acetate (19.6), cyclohexanol (23.3) ), Cyclohexanone (20.3), 1,4-dioxy Sun (20.5), dichloromethane (19.8), N, N-dimethylformamide (24.8), styrene (19.0), tetrachloroethylene (19.0), tetrahydrofuran (18.6), 1 -Butanol (23.3), 2-butanol (22,1), methanol (29.7), methyl ethyl ketone (19.0), methylcyclohexanol (21.3), methylcyclohexanone (19.0), chloroform ( 19.0), 1,2-dichloroethane (20.1), 1,2-dichloroethylene (18.4 to 18.6), 1,1,2,2-tetrachloroethane (19.8), Trichloroethylene (18.8), carbon disulfide (20.5), diethylene glycol monomethyl ether (ethyl cellosolve, 23.5), propylene glycol Nobutyl ether (18.4), isopropyl alcohol (18.0), xylene (18.0), acetic acid-n-propyl (18.0), toluene (18.2), carbon tetrachloride (17.6), Ethylbenzene (18.0) and trimethylbenzene (18.0). The numbers in parentheses are typical SP values for each solvent, and the unit is (MPa) ^0.5 . The solvent may contain water (47.9).

  The total amount of all solvents is 99.9% by mass or less, 99% by mass or less, 97% by mass or less, 95% by mass or less, 92% by mass or less, 90% by mass or less, or the total amount of the release agent. It may be 85 mass% or less, and may be 60 mass% or more, 70 mass% or more, 80 mass% or more, or 85 mass% or more. The total amount of all the solvents may be 92% by mass or less, 90% by mass or less, or 85% by mass or less, and more than 30% by mass and more than 50% by mass with respect to the total amount of the release agent composition. , More than 60%, more than 65%, more than 70%, or more than 75% by weight.

From the viewpoint of imparting sufficient releasability to the object sprayed with the release agent composition, at least one of 17.5 (MPa) ^0.5 or less of the solvent is contained in the release agent. Of these, a solvent having the highest boiling point is preferable.

<Additives>
The mold release agent may contain an additive as required in addition to the wax and the solvent. For example, a diluent, pigment, dispersant, silicone, modified silicone, amine catalyst, metal catalyst, ultraviolet absorber, light stabilizer, leveling agent, adhesion promoter, rheology control agent, polymerization initiator, etc., release agent It may contain an additive usually added to. In particular, the wax can be more stably dispersed in the solvent by adding a dispersant to the release agent.

<Liquid carbon dioxide>
Carbon dioxide in the release agent composition is in a liquid state. When the release agent composition is sprayed from the spray nozzle and released from the pressurized state, the carbon dioxide that has been compressed into the liquid state is instantly vaporized and the volume thereof is greatly expanded. Due to the force at that time, the release agent composition becomes a fine mist.

The density of the liquid carbon dioxide in the release agent composition is 700 kg / m ³ or more. The density of liquid carbon dioxide may be at 730 kg / ^{m 3} or more, may be at 750 kg / ^{m 3} or more, may be at 800 kg / ^{m 3} or more. The density of liquid carbon dioxide may be at 1100 kg / ^{m 3} or less, may be at 1000 kg / ^{m 3} or less, may be at 905 kg / ^{m 3} or less.

The density of liquid carbon dioxide is determined by the temperature and pressure of the release agent composition, that is, the temperature and pressure of carbon dioxide. The temperature and pressure of the release agent composition and liquid carbon dioxide may be in a range where carbon dioxide is liquid and the density is 700 kg / m ³ or more.

  For example, from the viewpoint that the critical temperature of carbon dioxide is 31.1 ° C., the temperature of the release agent composition (temperature of liquid carbon dioxide) is preferably 31 ° C. or lower. The temperature of the release agent composition (temperature of liquid carbon dioxide) may be 30.5 ° C. or lower, 30 ° C. or lower, and 29 ° C. or lower. The temperature of the release agent composition (temperature of liquid carbon dioxide) may be −50 ° C. or higher, may be −20 ° C. or higher, and may be 0 ° C. or higher.

  The pressure of the release agent composition (pressure of liquid carbon dioxide) can be 0.5 MPa or more, 2 MPa or more, 5 MPa or more, 7 MPa or more, 8 MPa or more, 9 MPa or more, or 10 MPa or more. Although there is no upper limit in particular, it can be 30 MPa or less, 20 MPa or less, 10 MPa or less. The pressure in this specification is an absolute pressure (MPa).

In addition, under the temperature and pressure conditions close to the critical temperature (31.1 ° C.) and the critical pressure (7.38 MPa), liquid carbon dioxide having a density of less than 700 kg / m ³ may be present. (Sometimes called subcritical carbon dioxide) is excluded from the liquid carbon dioxide of the present invention.

  The compounding amount of the liquid carbon dioxide can be 2 parts by mass or more, 5 parts by mass or more, 10 parts by mass or more, or 20 parts by mass or more with respect to 100 parts by mass of the release agent. When the blending amount of liquid carbon dioxide is 2 parts by mass or more, the sprayed release agent composition becomes a finer mist, so that the liquid film of the release agent with higher leveling property and it was dried. A release film can be formed.

  According to such a release agent composition, sufficient releasability can be imparted to an object even by spray coating using carbon dioxide.

Then, the preparation method of such a mold release agent composition is demonstrated. The release agent composition is prepared by mixing the release agent and carbon dioxide, and setting the temperature and pressure of the mixture so that the carbon dioxide becomes a liquid and has a density of 700 kg / m ³ or more. can do. For example, the release agent composition can be prepared by mixing carbon dioxide having a liquid density of 700 kg / m ³ or more and the release agent. First, carbon dioxide in a state other than liquid (such as supercritical carbon dioxide) or carbon dioxide having a density of less than 700 kg / m ³ and liquid is mixed with the above release agent, and then necessary. The above release agent composition can also be obtained by adjusting the temperature and pressure of the mixture so that the carbon dioxide in the mixture becomes liquid and the density thereof is 700 kg / m ³ or more while mixing accordingly. Can be prepared. Mixing of the release agent and carbon dioxide can be performed, for example, by a line blend method using an in-line mixer.

  In one embodiment, the release agent composition can be prepared and sprayed using a two-component continuous mixing carbon dioxide coating apparatus as shown in FIG. In FIG. 1, a release agent containing wax and a solvent stored in a release agent tank 1 is pressurized to a predetermined pressure by a release agent high-pressure pump 2, and a predetermined temperature by a release agent heater 3. Until it is heated to the mixer 8. On the other hand, the liquid carbon dioxide stored in the carbon dioxide cylinder 4 is cooled and liquefied by the carbon dioxide cooler 5, and is added to a predetermined pressure by the carbon dioxide high pressure pump 6 (for example, a constant volume pump such as a plunger pump). After being pressurized and heated to a predetermined temperature by the carbon dioxide heater 7, it is supplied to the mixer 8. As the mixer 8, for example, an in-line mixer can be used. The release agent and liquid carbon dioxide are mixed in the mixer 8 to form a release agent composition.

The pressure of the release agent composition supplied from the mixer 8 to the spray nozzle 9 is adjusted by the carbon dioxide high pressure pump 6 and the release agent high pressure pump 2, and the release agent heater 3 and the carbon dioxide heater 7. Thus, the temperature of the release agent composition supplied from the mixer 8 to the spray nozzle 9 (for example, a spray gun) is adjusted. In this way, the carbon dioxide in the release agent composition supplied from the mixer 8 to the spray nozzle 9 can be adjusted to be liquid and have a density of 700 kg / m ³ or more. That is, in the coating apparatus of FIG. 1, the carbon dioxide high-pressure pump 6, the release agent high-pressure pump 2, the release agent heater 3, the carbon dioxide heater 7, and the mixer 8 are liquid and 700 kg / m. ^The mold release agent composition preparation part A which prepares the mold release agent composition containing the carbon dioxide which has a density of ³ or more is comprised.

  In the coating apparatus shown in FIG. 1, the wax and the solvent are preliminarily mixed and stored in a state where the wax is uniformly dispersed in the solvent. Good. Moreover, after mixing a mold release agent and liquid carbon dioxide, you may further mix a part of solvent.

The aspect of the release agent composition preparation part is not limited to the above, and the carbon dioxide in the release agent composition prepared by the release agent composition preparation part is a liquid and is 700 kg / m ³ or more. As long as it has the density of, other aspects may be sufficient. For example, instead of the release agent heater 3 and the carbon dioxide heater 7, a temperature adjustment mechanism such as a heat exchanger is provided in the mixer 8, thereby adjusting the temperature of the release agent composition supplied to the spray nozzle 9. Alternatively, a temperature adjusting mechanism such as a heat exchanger is provided on the line connecting the mixer 8 and the spray nozzle 9, thereby adjusting the temperature of the release agent composition supplied to the spray nozzle 9. Also good. Further, instead of the carbon dioxide high-pressure pump 6 and the release agent high-pressure pump 2, a pressure adjusting mechanism such as a pump or a pressure reducing valve is provided on a line connecting the mixer 8 and the spray nozzle 9 to supply the spray nozzle 9. The pressure of the release agent composition may be adjusted. The release agent composition preparation unit accommodates the release agent composition, and the cylinder and the temperature and pressure are set so that the density of the liquid carbon dioxide in the interior is 700 kg / m ³ or more. It may be. Further, the carbon dioxide cooler 5 in the above embodiment may not be provided. Further, the release agent heater 3 and the carbon dioxide heater 7 may be omitted.

  Subsequently, a method of spraying the release agent composition prepared in this way onto the object from the spray nozzle to impart release properties to the object will be described. A method for imparting releasability to an object includes a step of spraying a release agent composition from a spray nozzle to form a liquid film of the release agent on the object, and drying and releasing the liquid film of the release agent. Forming a mold film.

  For example, in FIG. 1, the release agent composition obtained by the mixer 8 is in a pressurized state and can be sprayed into the atmosphere through the spray nozzle 9. When the release agent composition is sprayed, the compressed carbon dioxide instantly vaporizes and its volume expands significantly. Due to the force at that time, the release agent composition becomes a fine mist (mist). By bringing this mist into contact with the object, a liquid film of a release agent is formed on the surface of the object. Thereafter, by drying the liquid film, a release film that imparts releasability to the object is formed.

According to the release agent composition or method of the present invention, the release agent composition supplied to the spray nozzle includes a release agent containing a solvent having an SP value of 17.5 (MPa) ^0.5 or less, and 700 kg / Since it contains liquid carbon dioxide having a density of m ³ or more, sufficient releasability can be imparted to the object. The reason why the releasability is high is not clear, but the present inventors infer the reason as follows.
Since a solvent containing a solvent having an SP value of 17.5 (MPa) of ^0.5 or less is compatible with the wax, the waxes are less likely to aggregate when or after the release agent composition is sprayed to vaporize carbon dioxide. . Therefore, the state in which the wax is dispersed in the solvent can be satisfactorily maintained, whereby a more uniform release film can be formed. In general, the lower the SP value, the lower the surface tension of the solvent and the better the leveling property. Furthermore, at least one of the solvents having an SP value of 17.5 (MPa) ^0.5 or less is preferably a solvent having the highest boiling point among all the solvents contained in the release agent. This is because the solvent that evaporates last among all the solvents is considered to act on the drying of the liquid film while maintaining the leveling property. This is because it is considered preferable that the solvent of ^0.5 or less evaporates at the end.
Furthermore, when the density of the liquid carbon dioxide in the release agent composition supplied to the spray nozzle 9 is 700 kg / m ³ or more, the density of the liquid carbon dioxide is close to the density of the solvent and / or the liquid. It is conceivable that the compatibility between the liquid carbon dioxide and the solvent is improved when the SP value of carbon dioxide is close to the SP value of the solvent. Accordingly, the mist diameter and composition uniformity of the release agent composition are improved, which may be one factor for improving the leveling property of the release film.
In addition, when the density of liquid carbon dioxide is 700 kg / m ³ or more, there is an effect that it is easy to perform quantitative supply by a constant volume pump such as a plunger pump.
As described above, according to the release agent composition or method of the present invention, it is possible to form a uniform release film with good leveling properties on the object, and therefore sufficient release properties for the object. It is guessed that can be granted.

  EXAMPLES Hereinafter, although an invention is concretely demonstrated based on an Example, this invention is not limited to a following example.

(Test Example 1)
The mold release agent composition is sprayed onto the surface of a mold for molding polyurethane foam, and the moldability of the polyurethane foam (molded foam) molded using this is determined from the mold and the appearance of the molded mold that has been released. evaluated. Specific test contents are shown below.

  In the two-component continuous mixing type carbon dioxide coating apparatus as shown in FIG. 1, the release agent was charged into the release agent tank 1. Table 1 shows the release agents used in the test examples. These release agents are all manufactured by Chukyo Yushi Co., Ltd. In Table 1, “NV” means the mass ratio of the non-volatile component (the main component is wax) in the release agent. The “minimum SP value in the solvent” means the SP value of the solvent having the lowest SP value among the solvents contained in the solvent. Furthermore, “petroleum hydrocarbons” are included in the solvent naphtha.

The flow rates of the release agent high-pressure pump 2 and the carbon dioxide high-pressure pump 6 were set so that the mixing ratio (mass ratio) of the release agent and carbon dioxide was the value shown in Table 2. In the mixer 8, a release agent and carbon dioxide were mixed under the conditions of a temperature of 20 ° C. and a pressure of 10 MPa to obtain a release agent composition. Carbon dioxide in the release agent composition is a liquid and has a density of 858 kg / m ³ . This mold release agent composition is uniformly sprayed (solid per 1 m ² ) onto an iron box-shaped mold (inner dimensions: 15 cm long, 20 cm wide, 5 cm deep, with lid with handle) heated to 60 ° C. About 5 g in terms of minutes) and dried for 1 minute. 40 parts by mass of polyol (MS-300 manufactured by Mitsui Toatsu) and 20 parts by mass of TDI / MDI = 1/1 as a polyurethane foam molding raw material were stirred and mixed at room temperature at 2000 rpm for 5 seconds, and this was immediately put into a mold. Poured, capped, and foam cured at 60 ° C. for 10 minutes. Thereafter, the mold release properties from the mold and the finished appearance of the molded foam surface were evaluated. The results are shown in Table 2.

  Evaluation of the finished appearance of the surface of the molded foam was performed by visually observing the roughness of the surface of the molded foam. Evaluation criteria: ◯ indicates no cell roughness; △ indicates cell roughness; × indicates severe cell roughness. Here, a cell refers to the bubble which forms a polyurethane foam, and a cell roughness refers to the state where the magnitude | size of a cell is non-uniform | heterogenous. Cell roughness means that the portion where the cell size is non-uniform is less than 50% of the entire observed surface, and that cell roughness is excessive, the portion where the cell size is non-uniform , Refers to a state that is 50% or more of the entire observed surface.

  Evaluation of releasability was performed by setting a spring balance on the handle of the mold lid, opening the lid, and measuring the load applied at that time. Evaluation criteria: ○ is less than 10 kg; x is 10 kg or more.

(Test Example 2)
The test was performed in the same manner as in Test Example 1 except that the mixing ratio (mass ratio) of the release agent and carbon dioxide was changed to the values shown in Table 3. The results are shown in Table 3.

  From the results shown in Tables 2 and 3, in the examples, the finished appearance and releasability of the molded foam were better than those in the comparative example. This indicates that the mold release agent composition in the examples was able to impart good release properties to the mold. That is, according to the release agent composition in the examples, good release properties can be imparted to the object (mold).

(Test Example 3)
The mixing ratio was set so that 10 parts by mass of liquid carbon dioxide was mixed with 100 parts by mass of the release agent, and the test was performed in the same manner as in 1. As a mold release agent, “resilient U-488” was used. Table 4 shows the temperature and pressure of the obtained release agent composition. The density (kg / m ³ ) of liquid carbon dioxide shown in Table 4 represents the density of liquid carbon dioxide in the obtained release agent composition. The test results are shown in Table 4. In addition, although the temperature and pressure of the mold release agent composition of Example 14 are near the critical point, since the temperature is lower than the critical temperature, carbon dioxide exists in a liquid state.

As shown in Table 4, when the density of liquid carbon dioxide is 700 kg / m ³ or more, the density of the liquid carbon dioxide is lower than that of Examples 13, 14 and 18 where the density of liquid carbon dioxide is less than 700 kg / m ³ . The finished appearance and releasability were good.

DESCRIPTION OF SYMBOLS 1 ... Release agent tank, 2 ... Release agent high pressure pump, 3 ... Release agent heater, 4 ... Carbon dioxide cylinder, 5 ... Carbon dioxide cooler, 6 ... Carbon dioxide high pressure pump, 7 ... Carbon dioxide heater, 8 ... Mixer, 9 ... Spray nozzle, A ... Release agent composition preparation section.

Claims (7)

A mold release agent containing a wax and a solvent, and liquid carbon dioxide,
The solvent is liquid at 20 ° C. and 1 atm,
The solvent includes a solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less,
The liquid carbon dioxide is a release agent composition having a density of 700 kg / m ³ or more. The solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less is selected from the group consisting of aliphatic hydrocarbons, gasoline, kerosene, coal tar naphtha, petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, and mineral spirits. The release agent composition according to claim 1, which is a weak solvent to be selected.   The mold release agent composition of Claim 1 or 2 whose melting | fusing point of the said wax is 30-140 degreeC.   The mold release agent composition according to any one of claims 1 to 3, wherein the wax is a polyethylene wax or a synthetic hydrocarbon wax.   The mold release agent composition as described in any one of Claims 1-4 whose compounding quantity of the said wax is 0.1-40 mass% with respect to the mold release agent whole quantity. Spraying the release agent composition according to any one of claims 1 to 5 from a nozzle to form a liquid film of the release agent on an object;
Forming a mold release film by drying a liquid film of the mold release agent. A coating apparatus comprising a release agent composition preparation unit for preparing a release agent composition, and a spray nozzle for spraying the prepared release agent composition,
The release agent composition includes a release agent containing a wax and a solvent, and liquid carbon dioxide,
The solvent is liquid at 20 ° C. and 1 atm,
The solvent includes a solvent having a solubility parameter of 17.5 (MPa) ^0.5 or less,
The coating apparatus, wherein the liquid carbon dioxide has a density of 700 kg / m ³ or more.

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