JP2020093500A - Protective cover, and mold for foaming resin - Google Patents

Abstract

To provide a protective cover capable of easily protecting a contact surface with which a foaming resin is in contact in a mold for the foaming resin, and the mold for the foaming resin.SOLUTION: In a mold 30 for a foaming resin, a front side 32A of a support member 32 which the mold 30 has is a contact surface with which the foaming resin is in contact. A protective cover 10 is formed into a shape in correspondence with the front side 32A being the contact surface, contains a polyolefin as its forming material, and covers the front side 32A of the support member 32 to suppress the adhesion of the foaming resin, and protect the front side 32A.SELECTED DRAWING: Figure 2

Description

The present invention relates to a molding die for foamed resin and a protective cover capable of protecting a contact surface in the die which comes into contact with the foamed resin, and a molding die for foamed resin.

For example, foamed resin moldings used as interior parts for automobiles such as instrument panels, center consoles, door trims, seats, various home appliances, and various furniture are cavity formed in the mold. It is formed into a predetermined shape by injecting a foamed resin into it and solidifying it. In many cases, urethane resin, melamine resin, or the like is used as the foamed resin, and the foamed resin such as the urethane resin or melamine resin has adhesiveness. As a result, the molded product may adhere to the surface of the cavity or the like and cannot be released from the mold, and the injection port may be clogged with the cured foamed resin. Therefore, the molding die using a foamed resin such as a urethane resin or a melamine resin is devised so that the foamed resin is not adhered to the contact surface in the mold such as the surface of the cavity or the injection port which contacts the foamed resin.
As such a device, there is a method of applying a release agent containing a silicone resin or the like to the contact surface of the molding die. However, the release agent has problems such as soiling the surface of the molded product and making it difficult to coat the surface of the molded product. Therefore, for example, as described in Patent Documents 1 to 4, a method of protecting a contact surface by providing a coating film containing a fluororesin such as polytetrafluoroethylene on the contact surface with the foamed resin in the mold Is proposed.

JP, 2003-34049, A JP, 2011-240587, A JP, 2012-24955, A JP, 2013-95043, A JP, 2010-240973, A

It is difficult for a foamed resin such as a urethane resin or a melamine resin to adhere to the coating film containing the fluororesin described above, and such a coating film shows suitable performance for suppressing the adhesion of the foamed resin. However, since the coating containing fluororesin is soft and has microscopic pinholes formed, it may peel off after repeated use, or foam resin may enter the pinholes and accumulate, preventing adhesion. However, there is a drawback that the performance of is reduced. Then, when the performance of suppressing adhesion is deteriorated, it is necessary to remove the coating applied to the contact surface by blasting and then to apply the coating to the contact surface again, as described in Patent Document 5, for example. is there. Therefore, the protection of the contact surface of the mold with the coating containing the fluororesin has a problem that the work for maintaining the performance of the coating is complicated and the cost is increased.

The present invention has been made by paying attention to the problems existing in such conventional techniques. An object of the invention is to provide a mold for foamed resin and a mold for foamed resin, which can easily protect a contact surface with which the foamed resin comes into contact.

As a means for solving the above-mentioned conventional problems, the invention of a protective cover according to claim 1 is a protective cover for covering a contact surface with which a foaming resin contacts with a mold for foaming resin, wherein The gist is that it is formed in a corresponding shape and contains polyolefin as a forming material.
A second aspect of the present invention is based on the first aspect, wherein the content of the polyolefin is 80% by mass or more when the total amount of the forming material is 100% by mass.
A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the polyolefin is polypropylene or polyethylene.
The invention of a vehicle part according to claim 4 is the invention according to claim 3, wherein the content of the polypropylene is 50 to 80 mass% when the total amount of the forming material is 100 mass %. The gist is that the content of the polyethylene is 20 to 50% by mass.
According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the molding die is an insert-molded article formed by integrating an insert member and the foamed resin. Which has a mold body into which the insert member is loaded, and a support member which is detachably attached to the inside of the mold body. The gist is that it is formed in a shape that covers the contact surface of the member.
The invention according to claim 6 is the invention according to claim 5, wherein the support member is provided with an injection port for injecting the foamed resin into a mold, and the protective cover is provided with the injection port. A fitting portion having a shape corresponding to is provided, and the gist is that the protective cover is fixed to the support member by fitting the fitting portion into the injection port.
The invention of a molding die for foamed resin according to claim 7 is that the contact surface with which the foamed resin comes into contact is covered by the protective cover according to any one of claims 1 to 4. Use as a summary.

[Action]
The protective cover of the present invention is formed of a forming material containing a polyolefin into a shape corresponding to a contact surface of a molding die with which the foamed resin comes into contact. Therefore, the contact surface can be easily protected by the protective cover only by attaching the protective cover to the contact surface. This protective cover does not need to be replaced frequently because the foamed resin is less likely to be adhered and can be used repeatedly because the forming material contains polyolefin. Furthermore, the protective cover can be easily replaced if necessary. Therefore, by using the protective cover, it is possible to easily protect the contact surface of the molding die with which the foamed resin comes into contact.
Further, when the content of the polyolefin is 80% by mass or more, with the total amount of the forming material being 100% by mass, the adhesion of the foamed resin to the protective cover can be suitably suppressed.
Further, when the polyolefin of the forming material is polypropylene and polyethylene, the mechanical strength and heat resistance of polypropylene and the moldability of polyethylene can be suitably exhibited.
Further, when the content of polypropylene is 50 to 80 mass% and the content of polyethylene is 20 to 50 mass% with the total amount of the forming material being 100 mass %, mechanical strength and heat resistance of polypropylene and good polyethylene Moldability can be exhibited well.
Further, when the molding die is used for molding an insert-molded product and has a mold body and a support member detachably attached to the inside of the mold body, the protective cover is a support. It is useful for protecting the contact surface of the member.
Further, when the support member is provided with an injection port for injecting the foamed resin into the mold, a protective cover is provided with a fitting part having a shape corresponding to the injection port, and the fitting part is fitted into the injection port for protection. The cover can be suitably fixed to the support member, and the inner peripheral surface of the injection port can be protected.
The mold for the foamed resin of the present invention has the above-mentioned protective cover to cover the contact surface with which the foamed resin comes into contact, so that the protective cover suppresses adhesion of the foamed resin to the contact surface. It is possible to suppress the occurrence of problems such as being unable to be released from the mold by being adhered to the contact surface and clogging of the injection port of the foamed resin. Then, the protective cover can be attached to the molding die simply by attaching the protective cover to the contact surface, and if necessary, the protective cover can be easily replaced. Since the foamed resin is hard to adhere to the protective cover including the protective cover and the protective cover can be repeatedly used, the contact surface with which the foamed resin comes into contact can be easily protected in the mold for the foamed resin.

〔effect〕
ADVANTAGE OF THE INVENTION According to this invention, in the mold for foamed resin, the protective cover and the mold for foamed resin which can easily protect the contact surface which a foamed resin contacts can be provided.

The perspective view which shows the protective cover of an Example. FIG. 7 is an exploded perspective view showing a state in which the protective cover of the embodiment is attached to the support member. The perspective view which shows the back surface of the support member of an Example. The perspective view which shows the instrument panel which is the insert molding of an Example. FIG. 5 is a sectional view taken along line 5-5 of FIG. 4. Sectional drawing which expanded a part which shows the state which shape|molds an instrument panel. Sectional drawing which expanded a part which shows the state which forms an instrument panel.

An embodiment of the present invention will be described below.
The protective cover (10) of the present invention is used for a molding die (30) for foamed resin, and in this molding die (30), the contact surface with which the foamed resin comes into contact is covered and protected. is there.
Further, in the molding die (30) of the present invention, a protective cover (10) is attached to the contact surface with which the foamed resin comes into contact, so that the contact surface is protected from adhesion of the molded product or the cured foamed resin. You can
The protective cover (10) is formed of a forming material containing polyolefin so as to cover the contact surface of the molding die (30) and is formed in a shape corresponding to the contact surface.

The foamed resin is not particularly limited as to the type of resin such as a thermoplastic resin or a thermosetting resin, a liquid state, a solid state, etc., and any commonly used foamed resin may be used. can do.
The foamed resin is preferably one having adhesiveness, since the protection of the contact surface of the molding die (30) by the protective cover (10) is particularly useful. Examples of the foamed resin having the adhesive property include those having polarity in the molecule and using as a raw material a compound having a carbonyl group or a hydroxy group as a functional group.
Specifically, as the foamed resin having adhesiveness, a urethane resin using a compound having an isocyanate group and a compound having a hydroxy group as raw materials, and a phenol having a hydroxy group and formaldehyde having a carbonyl group as raw materials Phenol resin, melamine resin using methylol melamine having a hydroxy group generated from melamine and formaldehyde as a raw material, epoxy resin using a prepolymer having an epoxy group (carbonyl group) as a raw material, urea having a carbonyl group and formaldehyde Examples thereof include a urea resin using as a raw material, and an unsaturated polyester resin using a polyalcohol having a hydroxy group and a polycarboxylic acid having a carbonyl group as a raw material. The foamed resin is a urethane resin, a phenol resin, a melamine resin, an epoxy resin, a urea resin, and an unsaturated polyester from the viewpoint that protection of the contact surface of the molding die (30) by the protective cover (10) is particularly useful. More preferably, it is at least one selected from the resins.

The molding die (30) is not particularly limited as to the molding method in which the molding die (30) is used. As a molding method, a cast foam molding method of foaming a liquid resin in a state where gas is supersaturated in a mold etc., a melt foam molding method of foaming a resin in a fluid state by heating, a resin A solid phase foam molding method in which foaming is performed in a solid state can be used. Among these molding methods, in the cast foaming method, the liquid resin reacts and cures in the mold to form a foamed resin. Contact surface protection is useful.
In addition, in the insert molding method, which is one of the cast foam molding methods, an insert member (21, 23) formed in a predetermined shape is loaded into a mold, and the insert member (21, 23) and the foamed resin are formed in the mold. It is a molding method in which and are integrated to obtain an insert-molded product (20). In this insert molding method, in order to bond and integrate the insert members (21, 23) and the foamed resin, a foamed resin having high adhesiveness such as the above-mentioned urethane resin or melamine resin is used. Therefore, protection of the contact surface of the molding die (30) with the protective cover (10) is extremely useful. The insert-molded article obtained by the insert-molding method includes, for example, a base material (21) such as an instrument panel (20), a door trim, a center console panel, and a sheet, and a foam layer (a layer laminated on the surface of the base material (21) ( 22) and a skin material (23) laminated on the surface of the foam layer (22).
The contact surface is not particularly limited as long as it is the surface of the portion of the molding die (30) that contacts the foamed resin. Specifically, as the contact surface of the molding die, the inner surface of the injection port (33) for the foamed resin, the cavity surface (molding surface) in the mold, and the surface of the support member (32) for adjusting the flow of the foamed resin in the mold. Are exemplified.

The protective cover (10) is formed in a predetermined shape by a predetermined molding method, and this molding method is not particularly limited, and examples thereof include injection molding, vacuum molding, pressure molding, and vacuum pressure molding. Among these forming methods, the vacuum forming, the pressure forming, and the vacuum forming, in which the sheet-shaped forming material is used to deform it into a predetermined shape, have a simple mold configuration and form the protective cover (10) in a short time. Therefore, it is a preferable molding method.
The material for forming the protective cover (10) is not particularly limited as long as it contains polyolefin. Since polyolefin has no polarity in the molecule, it is particularly polar in the above-mentioned molecule, and the compound having a carbonyl group or a hydroxy group has a property that the foamed resin used as a raw material is not adhered. Have
The content of the polyolefin is preferably 80% by mass or more, more preferably 85% by mass or more, still more preferably 90% by mass or more, when the total amount of the forming material is 100% by mass. When the content of the polyolefin is too low, the performance of suppressing the adhesion of the foamed resin tends to be poor.

Examples of the above-mentioned polyolefin include polypropylene, polyethylene, polybutylene, polymethylpentene and the like.
Here, it is desirable that the protective cover (10) has heat resistance such that it can withstand heat generation during molding of the foamed resin. Further, it is desirable that the protective cover (10) has a shape-retaining property such that the protective cover (10) does not bend or distort while covering the contact surface of the mold. Further, it is desirable that the protective cover (10) has a formability capable of deep drawing, particularly when formed by vacuum forming or the like.
Among the above-mentioned polyolefins, polypropylene is preferable as a material for forming the protective cover (10) from the viewpoint of heat resistance and shape retention. Polyethylene is preferable as a material for forming the protective cover (10) from the viewpoint of moldability. A mixture of polypropylene and polyethylene is more preferable as a material for forming the protective cover (10) from the viewpoint of heat resistance, shape retention and moldability.

When the above-mentioned polyolefin is a mixture of polypropylene and polyethylene, the content of polypropylene may be 50 to 80% by mass from the viewpoint of heat resistance, shape retention and moldability, with the total amount of the forming material being 100% by mass. The content of polyethylene is preferably 20 to 50% by mass. The polypropylene content is more preferably 55 to 75% by mass, further preferably 60 to 70% by mass. The content of polyethylene is more preferably 25 to 45% by mass, further preferably 30 to 40% by mass.
When the polypropylene content is excessively high and the polyethylene content is excessively low, the protective cover (10) tends to have poor moldability. When the polypropylene content is too low and the polyethylene content is too high, the protective cover (10) tends to be inferior in heat resistance and shape retention.

The protective cover (10) has a heat resistant temperature of preferably 90° C. or higher, more preferably 110, from the viewpoint of satisfying the heat resistance required for the mold (30) for foamed resin. ℃ or more, more preferably 120 ℃ or more. The heat resistant temperature is the value of the continuous use temperature specified in UL746B.
The above-mentioned polypropylene has a heat resistant temperature of 120 to 130° C., and polyethylene has a heat resistant temperature of 90° C., and is useful as a forming material usable for the protective cover (10) of the mold (30) for the foamed resin. Is.

If the water absorption is high, the protective cover (10) swells by absorbing the water generated when the raw material of the foamed resin is reacted and solidified in the molding die (30) in the casting foam molding method, It becomes inferior in dimensional stability. Therefore, the protective cover (10) preferably has a water absorption rate of 0.1% or less, more preferably 0.06% or less, still more preferably 0.03%, from the viewpoint of maintaining dimensional stability. It is below.
The water absorption rate is a value measured by a test method specified in ASTM D570 under the conditions of 23° C. and immersion for 24 hours.
The above-mentioned polyethylene has a water absorption rate of less than 0.01%, and polypropylene has a water absorption rate of 0.01% to 0.03%, and is useful as a protective cover (10) for a molding die (30) for a foamed resin. Is.

The thickness of the protective cover (10) is preferably 0.1 mm to 2 mm, more preferably 0.2 mm to 1.5 mm, and further preferably 0.3 mm from the viewpoint of use in the molding die (30) for foamed resin. ~1 mm.
If the protective cover (10) is excessively thin, it tends to be inferior in shape retention, and also tends to be inferior in moldability in that it easily breaks when formed into a predetermined shape by vacuum molding or the like. If the protective cover (10) is too thick, it will be difficult to adhere to the contact surface of the mold (30).

As long as the material for forming the protective cover (10) contains polyolefin, a synthetic resin other than polyolefin can be blended within a range that does not affect the moldability, heat resistance and mechanical strength.
Other synthetic resins include polyethylene terephthalate, ester-based resins such as thermoplastic polyester, polyvinyl chloride, vinylidene chloride copolymer, vinyl-based resins such as ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, polystyrene. , Polyamide, polyacetal, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyphenylene ether, polyphenylene oxide, polysulfone, polyether sulfone, polyphenylene sulfide, polyarylate, polyether ether ketone, crystalline polyester, polyamideimide, polyimide, polyetherimide, Examples thereof include polyaminobismaleimide, methylpentene copolymer, cellulose acetate and the like.
When a synthetic resin other than polyolefin is mixed with the forming material, the mixing ratio is preferably less than 10% by mass, more preferably 8% by mass or less, further preferably 5% by mass or less, with the total amount of the forming material being 100% by mass. is there.

Further, an additive can be added to the material for forming the protective cover (10) within a range that does not affect the moldability, heat resistance and mechanical strength.
As additives, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, calcium sulfite, calcium phosphate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, magnesium oxide, titanium oxide, iron oxide, zinc oxide, alumina, silica , Colloidal silica, mica, diatomaceous earth, dolomite, gypsum, talc, clay, asbestos, mica, calcium silicate, bentonite, white carbon, carbon black, iron powder, aluminum powder, glass powder, stone powder, blast furnace slag, fly ash, cement , Inorganic fillers such as zirconia powder; natural rubber or its derivatives; styrene-butadiene rubber, acrylonitrile-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, isoprene rubber, isoprene-isobutylene rubber, and other synthetic rubbers; polyvinyl alcohol, sodium alginate , Starch, starch derivatives, glue, gelatin, blood powder, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, polyacrylate, polyacrylamide and other water-soluble polymers and natural gums; wood flour, walnut flour, coconut dust powder, wheat flour, rice flour Organic fillers such as; higher fatty acids such as stearic acid and palmitic acid; higher alcohols such as palmityl alcohol and stearyl alcohol; esters of fatty acids such as butyryl stearate and glycerin monostearate; fatty acid amides; carnauba wax, etc. Natural waxes, synthetic waxes; paraffins, paraffin oils, silicone oils, silicone resins, fluororesins, polyvinyl alcohol, release agents such as grease; azodicarbonamide, dinitrosopentamethylenetetramine, P,P'- Organic blowing agents such as oxybis(benzenesulfonyl hydrazide) and azobis-2,2'-(2-methylgropionitrile); inorganic blowing agents such as sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate; silas balloon, perlite, Hollow particles such as glass balloons, foam glass, hollow ceramics; plastic foams and foam particles such as expanded polyethylene, expanded polystyrene, expanded polypropylene; pigments, dyes, antioxidants, antistatic agents, crystallization accelerators, phosphorus-based Compounds, nitrogen compounds, sulfur compounds, boron compounds, bromine compounds, guanidine compounds, phosphate compounds, phosphoric acid ester compounds, flame retardants such as amino resins, flame retardants, insect repellents, preservatives, Waxes, surfactants, lubricants, aging Inhibitors, UV absorbers; phthalate plasticizers such as DBP, DOP and dicyclohexyl phthalate, and other plasticizers such as tricresyl phosphate.
When the above-mentioned additive is added to the forming material, the addition rate is preferably less than 10% by mass, more preferably 8% by mass or less, further preferably 5% by mass or less, with the total amount of the forming material being 100% by mass. ..

Hereinafter, an embodiment of the protective cover 10 will be described with reference to the drawings.
The protective cover 10 of the present embodiment is used in a molding die 30 for molding an instrument panel 20 which is a vehicle part as an insert molded product by an insert molding method which is one of the cast foam molding methods. Is.

As shown in FIGS. 4 and 5, the instrument panel 20 includes a base material 21, a foam layer 22 laminated on the surface of the base material 21, and a skin material 23 laminated on the surface of the foam layer 22. Have (see FIG. 5).
The material of the base material 21 is not particularly limited as long as the above-mentioned foamed resin can be adhered thereto, and synthetic resin such as polyester, ABS resin, AGS (acrylonitrile/styrene/glass fiber) resin and modified polyolefin, iron, Metals such as stainless steel and aluminum are used. This base material 21 has an outer shape that is substantially the same as the outer shape of the instrument panel 20 except that it has a portion for providing the foam layer 22 and the skin material 23 on the surface thereof. What is formed into a predetermined shape before molding 20 is used.
The foam layer 22 is formed in a shape along the surface of the base material 21 by using the above-mentioned foam resin and using the molding die 30. In this embodiment, a liquid polyurethane foam having high adhesiveness is used as the foam resin forming the foam layer 22.
The material of the skin material 23 is not particularly limited as long as the foamed resin described above can be adhered thereto, and synthetic resins such as vinyl chloride resin and urethane resin, or impregnated with cloth such as knitted fabric or nonwoven fabric with these synthetic resins. Synthetic leather or natural leather is used. The skin material 23 is formed into a predetermined shape before the instrument panel 20 is molded so that the outer shape thereof is substantially the same as the outer shape of the instrument panel 20.

In the instrument panel 20, the base material 21 and the skin material 23 are adhered to each other via the foam layer 22, and the base material 21, the skin material 23, and the foam layer 22 are integrated.
A hole 24 for mounting a meter panel (not shown) is provided in the upper part of the center of the instrument panel 20. The hole 24 is provided in the base material 21 in advance.
It should be noted that the skin material 23 is not provided with the holes 24 in advance when it is formed, and as shown in FIG. 7, after the foam layer 22 is insert-molded, the pores 24 of the foam layer 22 and the skin material 23 are not formed. The hole 24 is formed by cutting the corresponding portion with the cutter 36.

As shown in FIG. 6, the molding die 30 is detachably attached to the die body 31 in which the base material 21 and the skin material 23 of the instrument panel 20 are loaded as insert members, and the die body 31. And a support member 32.
The mold main body 31 has a lower mold 31A and an upper mold 31B, a skin member 23 is mounted on the lower mold 31A, and a base material 21 is mounted on the upper mold 31B. A cavity 31C for forming the foam layer 22 is formed between the base material 21 and the skin material 23.

As shown in FIGS. 2 and 3, the support member 32 is formed in a plate shape in which the outer shape in a front view is a horizontally long substantially pentagonal shape having a shape corresponding to the hole 24 provided in the base material 21. An injection port 33 for injecting the foamed resin into the mold is formed at the center of the support member 32 so as to be circular in a front view.
A plurality of convex portions 34 are formed on the front surface 32</b>A of the support member 32. These convex portions 34 are for forming a cavity 31C for forming the foam layer 22 by forming a predetermined gap between the skin material 23 and the support member 32 (see FIG. 2). Further, on the back surface of the support member 32, a plurality of attachment portions 35 for attaching the support member 32 to the mold body 31 are provided in a protruding manner.
As shown in FIG. 6, the support member 32 is attached to the upper mold 31B of the mold main body 31 at a position that closes the hole 24 provided in the base material 21. The support member 32 forms a cavity 31C for forming the foam layer 22 together with the base material 21 and the skin material 23. Then, as indicated by the arrow in FIG. 6, the support member 32 blocks the inflow of the foamed resin into the hole portion 24 while allowing the foamed resin injected from the injection port 33 to flow into the cavity 31C. The flow of the foamed resin is adjusted.

The support member 32 forms a cavity 31C together with the base material 21 and the skin material 23, and the front surface 32A and the inner peripheral surface of the injection port 33 for the foamed resin serve as a contact surface in contact with the foamed resin. The protective cover 10 of this embodiment is formed so as to protect these contact surfaces.
As shown in FIG. 1, the protection cover 10 is formed in a thin plate shape of a horizontally long substantially pentagonal shape in a front view, corresponding to the outer shape of the support member 32 in a front view.
A fitting portion (through hole) 11 is provided on the front surface of the protective cover 10 at a substantially central portion. The fitting portion 11 is formed in a cylindrical shape extending from the front surface to the back surface of the protective cover 10, one end portion is opened at the front surface of the protective cover 10, and the other end portion is opened at a position apart from the rear surface of the protective cover 10. Has been done. The fitting portion 11 is set such that the outer diameter thereof is substantially the same as the inner diameter of the injection port 33 of the support member 32.
Further, on the protective cover 10, a plurality of protrusions 12 are formed so as to protrude from the front surface so as to have positions and shapes corresponding to the plurality of protrusions 34 provided on the front surface 32A of the support member 32. These protrusions 12 are formed in a hollow shape, and are formed so that the protrusions 34 of the support member 32 can be housed inside the protrusions 12.

As shown in FIG. 2, in the protective cover 10, the fitting portion 11 is fitted into the injection port 33 of the support member 32, and the convex portion 34 of the support member 32 is housed in each protrusion 12 to support the support member. It is attached to the front surface 32A of 32.
As shown in FIG. 6, in the molding die 30, a die member 37 configured by covering the support member 32 with the protective cover 10 is attached inside the die body 31. Then, the foamed resin is injected into the cavity 31C of the mold body 31 from the injection port 33 of the support member 32 forming the mold member 37, and the insert molding of the instrument panel 20 is performed.
As shown in FIG. 7, in the instrument panel 20 released from the molding die 30, the hole 24 is closed by the foam layer 22 and the skin material 23. The instrument panel 20 is formed by cutting the portion corresponding to the hole 24 with the cutter 36 and opening the hole 24.

As described above, the protective cover 10 can be mounted on the support member 32 only by being attached to the front surface 32A of the support member 32 so that the fitting portion 11 is fitted into the injection port 33 of the support member 32. It can be performed easily (see FIG. 2).
Further, the protective cover 10 covers the front surface 32A of the support member 32 and the inner peripheral surface of the injection port 33, which are contact surfaces that come into contact with the foamed resin, so that the foamed resin is bonded to the contact surface during insert molding. Can be prevented (see FIG. 6).
Further, since the protective cover 10 contains polyolefin as a forming material, the foamed resin is unlikely to adhere to the protective cover 10 and can be repeatedly used.
The protective cover 10 can be mass-produced by a vacuum forming method or the like. When the protective cover 10 cannot be used due to deformation or breakage, the old protective cover 10 is removed from the support member 32 and the new protective cover 10 is attached. It can be easily replaced simply by mounting it on the support member 32.
From the above, the protective cover 10 described above can easily protect the contact surface that contacts the foamed resin.
Further, in the molding die 30 having the die member 36 and the die body 31, since the front surface 32A of the support member 32 of the die member 37 is covered with the protective cover 10, the foamed resin is bonded to the front surface 32A. Can be prevented. Furthermore, since the protective cover 10 is formed of polyolefin, the adhesion of the foamed resin to the mold member 37 (protective cover 10) can be suppressed.

INDUSTRIAL APPLICABILITY According to the protective cover of the present invention, in the mold for foamed resin, the contact surface with which the foamed resin comes into contact can be easily protected, so that it can be industrially used.

10 Protective Cover 11 Fitting Part 12 Projection 20 Instrument Panel 21 Insert Molded Product 21 Base Material 22 Foam Layer 23 Skin Material 24 Hole 30 Mold 31 Mold Main Body 31A Lower Mold 31B Upper Mold 31C Cavity 32 Support Member 32A Contact Surface Is the front face 33 Injection port 34 Convex portion 35 Mounting portion 36 Cutter 37 Mold member

Claims (7)

A protective cover for covering a contact surface of a foamed resin in contact with the foamed resin,
A protective cover formed in a shape corresponding to the contact surface and containing polyolefin as a forming material thereof. The protective cover according to claim 1, wherein the content of the polyolefin is 80% by mass or more when the total amount of the forming material is 100% by mass. The protective cover according to claim 1 or 2, wherein the polyolefin is polypropylene or polyethylene. The protective cover according to claim 3, wherein the content of the polypropylene is 50 to 80 mass% and the content of the polyethylene is 20 to 50 mass% when the total amount of the forming material is 100 mass %. The molding die is used for molding an insert-molded product obtained by integrating an insert member and the foamed resin, and a mold body into which the insert member is loaded, and the inside of the mold body. And a support member that is detachably attached,
The protective cover according to any one of claims 1 to 4, wherein the protective cover is formed in a shape that covers the contact surface of the support member. The support member is provided with an injection port for injecting the foamed resin into the mold,
The protective cover is provided with a fitting portion having a shape corresponding to the injection port,
The protection cover according to claim 5, wherein the protection cover is fixed to the support member by fitting the fitting portion into the injection port. A mold for foamed resin, wherein a contact surface with which the foamed resin comes into contact is covered with the protective cover according to any one of claims 1 to 4.

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