JP3495961B2 - Molding method of laminated resin molding - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a laminated resin molded body in which a skin material made of a thermoplastic resin and a foam layer made of a urethane resin are integrally molded.

[0002]

2. Description of the Related Art As a method for molding a molded article of this type, as described in 1, Japanese Patent Publication No. 5-1123, Japanese Patent Application Laid-Open No. 8-48201, etc., a thermoplastic resin such as vinyl chloride or polyolefin is used. It is known that a powder slush molded two-layer skin material and a foam layer made of a polyurethane resin are integrally molded.

In addition, 2, JP-A-6-106682,
As described in JP-A-7-214672, etc., in order to enhance the adhesive force between the skin material and the adherend,
It is known that an adhesive made of a terpene resin is interposed between the two.

Further, as described in JP-A-2-199164, a resin in which a terpene phenol resin is contained in a resin for molding a base material is known.

[0005]

However, in the case of the above-mentioned conventional example 1, the adhesive strength between the skin material and the foam layer was not sufficient, and there was a fear that they would be separated from each other.

Further, in the conventional example 2, the adhesive is applied to at least one of the skin material and the adherend, so that the applying step is required, and the applying step requires a large number of man-hours and facilities. However, it is not preferable in terms of mass productivity and manufacturing cost. In addition, in order to apply, it is necessary to mix the adhesive with an organic solvent that is unfavorable to the human body, and there has been a demand for improvement in terms of working environment.

Further, in the conventional example 3, the base material contains the terpene phenol resin, so that a mold release agent is required for molding the base material, resulting in an increase in the number of steps and cost.

The present invention was devised in view of the above problems, and its purpose is not to require a great number of man-hours and facilities and to have no adverse effect on the working environment. Another object of the present invention is to obtain an inexpensive laminated resin molding having an improved adhesive strength between the skin material and the foam layer.

[0009]

According to the present invention, a terpene resin is added only to a back surface layer of a skin material integrally molded with a foam layer.

[0010] Specifically, first solving means taken by the invention, using a forming shape type, and a foamed layer made of a urethane resin skin material and said surface skin material having a plurality of layers of a thermoplastic resin It is premised on a method for molding a laminated resin molded body that integrally molds. Then, a terpene resin having an OH group is added.
A thermoplastic resin is used to form a skin back surface layer of a skin material that adheres to the foam layer, and a foam layer is integrally formed on the skin back surface layer of the skin material.
Molding the laminated resin molding and shape, after demolding the laminated resin molding, it may improve adhesion by the terpene resin
The laminated resin molded body is heat-treated at a temperature .

The second solution provided by the present invention is as follows.
A molding die comprising a first molding die and a second molding die is prepared, and a skin surface layer formed by powder slush molding a thermoplastic resin,
A thermoplastic resin to which a terpene-based resin having an OH group is added is molded on the back surface of the above-mentioned skin surface layer by powder slush molding to form a skin material, and then, the skin material is the first skin surface layer. The urethane type foamed resin raw material, which is set so as to be in contact with the molding die and is injected between the skin material and the second molding die in the cavity formed by the first molding die and the second molding die, is foamed. Hardened and above the epidermis
Laminated resin molding by integrally forming a foam layer on the back surface layer of the material
Molding the, after demolding the laminated resin molding, the terpene
At a temperature capable of improving the adhesion with the resin is obtained by so applying pressurized heat treatment to the laminated resin molding.

Further, the third means for solving the problems of the present invention is the thermoplastic resin for molding the back surface layer of the skin according to the first or the second means, wherein the amount is 3 to 20 per 100 parts of the resin. The terpene-based resin is added in some parts.

According to the second means for solving the problems of the present invention, "the resin is injected between the skin material and the second molding die in the cavities formed by the first molding die and the second molding die. "Urethane-based foamed resin raw material" means a so-called closed injection method in which the urethane-based resin material is injected after closing both molds, or a so-called open injection method in which the urethane resin material is injected into the first mold and then the second mold is closed. It covers both cases.

The skin back surface layer of the skin material in the present invention means a layer forming the skin material excluding the skin surface layer forming the surface of the skin material, that is, a layer laminated on the back surface of the skin surface layer. To tell.

[0015]

The first resolution hand stage according to the present invention, since only the skin back layer for bonding the foam layer is molded by resin added terpene resin, eliminating the need for release agent in the molding process of the skin material In addition, the terpene-based resin added to the back surface layer of the skin and the urethane-based resin of the foam layer chemically react with each other in the heat treatment step of the molded body after demolding, and the adhesive force between the two is significantly improved.

When the terpene-based resin is added to the thermoplastic resin for forming the back surface layer of the skin, there is no need for a solvent such as an organic solvent, so there is no adverse effect on the working environment, and further, the molded product after demolding. Since the adhesive force can be strengthened simply by heat-treating, it is possible to further reduce the cost of manufacturing equipment and improve mass productivity.

Further, the second resolution hand stage is for forming a skin material by powder slush molding method, a resin for slush molding the skin back surface layer is a powdery thermoplastic resin, powdery terpene Since it is a resin with a resin added, it is not necessary to use a solvent such as an organic solvent, and since the terpene resin is not added to the resin forming the surface layer of the skin, it is possible to use a powder slush mold with a terpene resin. The skin material can be formed extremely easily without adhesion of the skin material.

Further, according to the third means for solving the problems, since 3 to 20 parts of the terpene resin is added to 100 parts of the thermoplastic resin for molding the back surface layer of the skin, the moldability of the back surface layer of the skin is improved. The adhesive strength with the foam layer can be improved without deteriorating the appearance and appearance of the surface layer due to deterioration.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

(Embodiment 1) FIG. 1 shows an automobile instrument panel 1 as a laminated resin molding to which the present invention is applied, 2 is a base material of the instrument panel 1, and 3 is an instrument panel 1.
Pad of.

As shown in FIG. 2, the cross-sectional shape of the pad 3 is such that in the concave accommodating portion 6 formed of the bottom wall 4 and the side wall 5 formed in the base material 2, the skin material 7 is on the surface and the side surface. A hard foam layer 8 is integrally laminated on the bottom wall 4 as a foam layer.

The skin material 7 is slush molded from a powder material of TPO (thermoplastic olefin) resin which is an olefin resin which is a thermoplastic resin, and is integrally formed on the skin surface layer 7a and the back side of the skin surface layer 7a. 2 has a back surface layer 7b formed by slush molding, and has a skin bending portion 7c formed by bending an edge of the back surface layer 7b.

The back surface layer 7b of the skin is formed of the TP.
Soft foam layer (foam layer) formed by powder slush molding with a resin material in which a foaming agent and a terpene-based resin, a terpene-based resin, are added to a powder material of O resin
The terpene phenol resin is added in an amount of 5 parts per 100 parts of the powder material of the TPO resin.

The expansion ratio of the back surface layer 7b of the skin is 4 times. In addition, the terpene phenol resin is not added to the TPO resin that forms the surface layer of the skin.

The hard foam layer 8 is formed from a resin material obtained by adding a foaming agent to a polyurethane resin, which is a urethane resin, and has a foaming ratio of 3 times.

The base material 2 is injection-molded using an olefin resin polypropylene (PP) resin raw material, and the bottom wall 4 of the accommodating portion 6 has an injection port 6a into which the polyurethane resin raw material is injected. It is open.

Reference numeral 9 is a sealing material for preventing the above-mentioned polyurethane resin raw material from flowing out to the surface side of the pad 3 in the step of molding the pad 3.

Next, a method of molding the pad 3 will be described with reference to FIGS.

Reference numeral 10 denotes a first molding die 10a and a second molding die 1
0b, and both molds 10a and 10b are openably and closably coupled by a hinge member 10c. And the injection nozzle 11 which injects a polyurethane resin raw material is attached to the 2nd shaping | molding die 10b.

The first molding die 10a has a two-layer skin material 7 preformed by the powder slush molding method.
Is set by a vacuum suction means (not shown) provided in the first molding die 10a so that the skin surface layer 7a contacts the molding surface of the first molding die 10a, and at the same time, the second molding die 10b. On the molding surface of the
The injection nozzle 11 is fitted into the injection port 6a, and the back surface of the base material 2 is abutted and set. The sealing material 9
Is adhered to the side wall 5 of the housing portion 6 of the base material 2.
(Figure 3)

After that, the first molding die 10a and the second molding die 10b are closed so that the surface of the skin bending portion 7c of the skin material 7 contacts the side wall 5 of the accommodating portion 6 via the sealing material 9, and thereafter, A polyurethane containing a foaming agent added to the cavity formed by the first molding die 10a and the second molding die 10b from the injection nozzle 11, that is, the housing portion 6 formed by the bottom wall 4 of the base material 2 and the skin material 7. The resin raw material 8a is injected (injection step). (Figure 4)

Thereafter, the polyurethane resin raw material 8a injected into the accommodating portion 6 is foamed and cured, the first molding die 10a and the second molding die 10b are opened, and the instrument panel 1 having the pad 3 is taken out (demolding step). ).

Then, the instrument panel 1 is mounted on the trolley A, and heat treatment is carried out in the warm air type heating device B. This heating temperature is a temperature at which the adhesive force of the skin back surface layer 7b to the hard foam layer 8 by the terpene phenol resin can be improved. In the case of the present embodiment, the heating temperature is about 115 ° C.
The heating time is about 10 minutes. (Heat treatment step) (Fig. 5)

Thereafter, the instrument panel 1 is taken out of the heating device B and naturally cooled to complete the molding of the instrument panel 1 as a molded body.

By the heat treatment step, the NCO group of the polyurethane resin of the hard foam layer 8 and the TP of the skin back surface layer 7b are formed.
By chemically reacting with the OH group of the terpene phenol resin added to the O resin and bonding, the skin back surface layer 7b and the hard foam layer 8, that is, the skin material 7 and the hard foam layer 8 are firmly bonded. .

Effect of Embodiment 1 Even with the above-mentioned skin material 7 made of TPO resin which is not compatible with the urethane type resin, the terpene phenol resin and the hard foam layer 8 added to the skin back surface layer 7b can be used. The polyurethane resin chemically reacts in the heat treatment step to firmly bond the skin back surface layer 7b and the hard foam layer 8 to each other.

Further, the addition of the terpene phenol resin to the TPO resin for molding the surface back surface layer 7b is in the form of solid (powder) without using a solvent such as an organic solvent, so that it has a bad influence on the working environment. Absent.

Further, in the molding step of molding the skin material 7 by the powder slush molding method, the terpene phenol resin is not added to the TPO resin for molding the skin surface layer, but only for the TPO resin for molding the skin back surface layer. Since it is added, it is not necessary to apply a mold release agent to the mold,
An inexpensive skin material can be easily obtained.

Further, since the adhesive strength can be strengthened simply by heat-treating the molded body (instrument panel 1) released from the molding die 10, spray coating or calendar coating using a conventional adhesive is carried out. Compared with the above, the manufacturing equipment becomes cheaper, the conventional masking work and the drying work after coating are eliminated, and the manufacturing process can be simplified, and as a result, mass productivity is improved.

Further, since the addition of the terpene phenol resin is set to 5 parts with respect to the thermoplastic resin for molding the skin back surface layer 7b, the appearance of the skin surface surface layer is not deteriorated due to deterioration of the moldability of the skin back surface layer 7b. The adhesive strength with the hard foam layer 8 can be improved.

Furthermore, since the skin material 7 is made of TPO resin, it can be recycled.

Modification of First Embodiment In the first embodiment, the skin material 7 is a powder slush molded skin material having two layers, but it may have three or more layers. For example, a skin material is a skin surface layer of the first layer, a back surface layer of the second layer laminated on the back surface of the skin surface layer, and a third layer laminated on the back surface of the second layer. In the case of a skin material having a three-layer structure including the back surface layer of No. 3, the terpene phenol resin may or may not be added to the second back surface layer.

The skin back surface layer 7b of the skin material 7 is not limited to the foam layer and may be a solid layer.

The hard foam layer 8 may be a semi-rigid foam layer or a soft foam layer.

Further, the skin material 7 is not limited to the TPO resin, but may be a thermoplastic resin such as polyolefin, polyester, polyethylene or the like, which has a relatively unfavorable compatibility with the urethane resin.

The terpene phenol resin to be added to the thermoplastic resin for molding the skin back surface layer 7b may be a terpene resin or a so-called terpene-based resin in addition to the terpene phenol resin. It may be within the range of 3 to 20 parts as shown in FIG.

[0047]

[Table 1] Table 1 shows the peel strength of the skin material with respect to the foam layer at each added part number of the terpene phenol resin, and the appearance appearance (unevenness) of the skin surface layer of the skin material. It is obtained by the same molding method as the form 1.

In Table 1, the peel strength of the skin material with respect to the foam layer is the N value obtained by pulling a laminate resin molding cut into a width of 25 mm in the direction perpendicular to the molding from the skin material side ( Newton value) is measured.
In addition, "material break" in Table 1 means that the polyurethane resin foam layer (hard) is broken.

As is clear from Table 1, when the amount of the terpene phenol resin added is 3 parts or less, the skin back surface layer 7b
The adhesive strength between the hard foam layer 8 and the hard foam layer 8 is reduced and it cannot be used for practical use. This deterioration of appearance is caused by deterioration of fluidity (moldability) of the powder resin in the powder slush molding process when the number of added parts of the terpene resin added to the powdery resin for molding the skin back surface layer is 20 parts or more. This is because the back surface layer of the skin is integrally formed in a granular form on the surface layer of the skin, and as a result, irregularities appear on the surface of the surface layer of the skin.

Further, the heating temperature and heating time of the molded body after demolding are not limited to those in the above-mentioned examples, and can be arbitrarily selected depending on the size of the molded body, the type of the molded body, and the like.

In addition to the instrument panel 1, the molded product can be easily applied to a laminated resin molded product such as a door trim, a glove lid, a console lid of an automobile.

Furthermore, the structure of the molded body may be a base material in which the concave accommodating portion 6 is not formed in the base material 2,
Further, it may be a laminated resin molding of the skin material 7 having no base material 2 and the hard foam layer 8.

(Embodiment 2) FIG. 6 shows a method for molding a laminated resin molding according to Embodiment 2 of the present invention. The same parts as those in Embodiment 1 are designated by the same reference numerals. And its description is omitted.

In the second embodiment, a polyurethane resin raw material added with a foaming agent for molding the hard foam layer 8 is injected into the molding die 10 by the open pouring method. With the molding die 10 opened, the skin material 7 is used. Is the same as that of the above-described first embodiment until the first mold is set to the first mold 10a and the base material 2 is set to the second mold 10b.

After the skin material 7 and the base material 2 are set on the molding die 10, the first molding die 10a is opened with the molding die 10 opened.
The polyurethane resin raw material 8a is injected from the injection nozzle 11 onto the back surface of the skin material 7 set to.

Thereafter, the molding die 10 is closed and the molding die 1
0 cavity, that is, the polyurethane resin raw material injected between the base material 2 and the skin material 7 is foamed and cured, and then demolded, and a molded body (instrument panel 1) is manufactured by the same method as in the first embodiment. To complete the molding operation.

Effect of Embodiment 2 In Embodiment 2, when molding a large-sized laminated resin molding, the polyurethane resin raw material 8a can be evenly injected into the back surface of the skin material 7, so that there is no lack of wall. The hard foam layer 8 can be molded.

Further, since it is not necessary to form an opening for injecting the resin raw material 8a in the base material 2, the rigidity of the base material 2 is not lowered.

[Brief description of drawings]

FIG. 1 is a perspective view of a laminated resin molded body according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a cross-sectional view showing a state in which the molding die for laminated resin molding of FIG. 1 is opened.

FIG. 4 is a cross-sectional view showing a step of injecting a resin raw material after closing the molding die of FIG.

FIG. 5 is a drawing showing a heating step of the laminated resin molding according to FIG.

FIG. 6 is a sectional view showing a step of injecting a resin material according to the second embodiment of the present invention.

[Explanation of symbols]

1 Instrument panel (laminated resin molding) 3 pads (laminated resin molding) 7 skin material 7a Skin surface layer 7b Skin back surface layer 8 Hard foam layer (foam layer) 8a Polyurethane (urethane type) resin raw material 10 Mold 10a First molding die 10b Second molding die

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI // B29K 75:00 B29K 75:00 105: 04 105: 04 B29L 31:58 B29L 31:58 (56) References 11-192678 (JP, A) JP 2-199164 (JP, A) JP 8-269252 (JP, A) JP 2000-344962 (JP, A) (58) Fields investigated (Int.Cl . ⁷ , DB name) B32B 1/00-35/00 B29C 39/00-39/44

Claims (3)

(57) [Claims] [Claim 1] with a mold, in the molding method of the laminated resin molding integrally forming a foamed layer made of urethane resin skin material and said surface skin material having a plurality of layers made of a thermoplastic resin, OH group Resin containing terpene-based resin
Mold the back surface layer of the skin material that adheres to the foam layer with grease.
Then, a foam layer is integrally formed and laminated on the back surface layer of the skin material.
Molding a resin molded body, the the laminated resin molding after demolding at temperatures capable of improving the adhesive force by the terpene resin
A method for molding a laminated resin molded body, characterized in that the laminated resin molded body is subjected to heat treatment. 2. A molding die comprising a first molding die and a second molding die is prepared, and a skin surface layer formed by powder slush molding a thermoplastic resin, and a thermoplastic resin to which a terpene-based resin having an OH group is added. A skin material comprising a skin back surface layer formed by powder slush molding on the back surface of the skin surface layer is formed,
Thereafter, the skin material is set so that the skin surface layer contacts the first mold, and the skin material and the second mold in the cavity formed by the first mold and the second mold. The urethane-based foamed resin raw material injected between the two is foam-cured to integrally form a foamed layer on the back surface layer of the above-mentioned skin material.
Molding the laminated resin molding, after demolding the laminated resin molding,
At a temperature that can improve the adhesive strength of the terpene-based resin
Method of molding a product layer resin molding characterized in that as subjected to pressurized heat treatment to the laminated resin molding. To 3. A thermoplastic resin for molding the skin back layer according to claim 1 or 2, characterized in that 3 to 20 parts terpene resin is added to the resin 100 parts
A method for molding the laminated resin molded article described.