JPH07100349B2 - Method for manufacturing laminate resin press-formed product - Google Patents

Description

TECHNICAL FIELD The present invention relates to the production of a press-molded product obtained by laminating a skin material on a resin substrate, for example, a resin press-molded product obtained by laminating a nonwoven fabric on the surface of a resin substrate such as a vehicle interior plate. Concerning the law. The present invention can be understood as an applied patent of Japanese Patent No. 1278242 (Japanese Patent Publication No. 59-23691) provided by the applicant.

2. Description of the Related Art For example, as a method of laminating a non-woven fabric on the surface of a resin substrate, Japanese Patent Publication No. 56-5729 is disclosed. This prior example shows a method in which a nonwoven fabric is pressure-bonded to a resin sheet extruded from a die and laminated. This prior example only presents that a flat plate on which a nonwoven fabric is crimped is provided as a core material, and not only teaches nothing about a series of techniques for laminating and press-molding, but crimping a laminated form of the nonwoven fabric, That is, it is only intended for the anchoring effect.

Generally, resin press-molded products are manufactured by reheating resin sheets stocked by the manufacturer to make them softened sheets, and then charge and mold them into a mold to perform press molding.However, when laminating a skin material such as the above non-woven fabric, A surface material is further charged on the surface of the softened resin sheet, and at the same time as press molding, the surface material is pressure-bonded to the softened resin sheet to achieve layering by the effect of adhesion or anchoring.

In addition, as another method, a method of adhering a skin material to a press-molded product by debonding the adhesive material, and the like are used.

Problems to be Solved by the Invention As described above, in the related art, it is not possible to recognize any disclosure regarding a specific method of forming a sheet of molten resin and laminating a skin material in a series of steps and press-molding.

In addition, when relying on the anchoring effect by pressure bonding or planar adhesion, it is not possible to manufacture a homogeneous, high-strength, highly reliable laminated resin press-formed product, which leads to the production of wrinkles and defective products such as adhesion defects. , Worsens the yield.

Further, in the method of press-bonding the skin material by press molding as in the latter example, deterioration of physical properties due to reheating of the base material, cracking and skin roughening due to this cannot be prevented, and heat energy for reheating a preformed sheet. However, the reheating causes an economic burden such as power consumption, and the productivity also deteriorates.

Further, in the former example, it is difficult to press-form a flat plate on which a nonwoven fabric is once laminated, and it is not technically possible to reheat and press-form the laminated plate.

In view of the above circumstances and problems, the present invention has been made in consideration of integrated production of resin sheet molding, skin material lamination, and press molding.

Means for Solving the Problems Thus, the present invention uses, as its means, a mixed resin of two or more kinds, and uses the heat retained when the resin sheet is melted at a melting point of the highest melting point resin or higher, While controlling the temperature of the resin sheet to a temperature equal to or higher than the melting point of the resin skin material such as non-woven fabric, the heat of the sheet promotes interfacial fusion of the skin material to obtain a strong laminate, and in the subsequent press molding, By grasping the temperature drop point in the range from the melting point of the lowest melting point resin, which is the maximum specific heat range, to the vicinity of the freezing point (crystallization peak temperature), it is preferable to perform mold injection while controlling the temperature (temperature control) so as to maintain this temperature range. By press-molding, the product is shaped and the planting of the skin material is stabilized.

In the present invention, the highest melting point resin component is used to set the proper temperature of the sheet for obtaining the interfacial fusion of the resin skin material so that it acts more effectively. Using the same type of resin as the skin material to make the mixed resin compatible, while making the mixed resin sheet and the interfacial fusion of the resin skin material sound based on the melting point of the highest melting point resin In addition, paying attention to the characteristic that the above-mentioned mixed resin starts solidification (crystallization) at a temperature slightly lower than the melting point of the lowest melting point resin component at the time of temperature drop after melting, and selecting the lowest melting point resin component within the maximum specific heat range. The temperature at a certain freezing point is selected, and the temperature at which the mold is charged is determined by this so that press molding can be properly performed.

As a suitable material for the resin having the highest melting point, polypropylene resin having the highest versatility as a resin skin material can be mentioned.

In view of this, the present invention uses a polypropylene resin as the highest melting point resin component and a resin containing a polyethylene resin as the lowest melting point resin component as a mixed resin, and further, uses the mixed resin to interfacially fuse a polypropylene resin skin material. Provide a way to do.

The present invention includes examples in which the mixed resin is compatible with the resin skin material but is not the same kind of resin.

In addition, as an invention related to the above, in order to maintain the set temperature (the temperature range from the melting point of the lowest melting point resin component to the vicinity of the freezing point) before the mold is inserted after the lamination, the resin sheet is used as an interface fusion surface of the resin skin material. The temperature was adjusted by radiant heat from the surface on the opposite side, so that the resin sheet, which is the molding base, was soaked to an appropriate temperature to remove the thermal adverse effect on the skin material, while properly performing the mold injection and press molding. A method for producing a laminate resin press-formed product is provided.

Effect According to the present invention, while processing the mixed resin into a resin sheet, the temperature can be adjusted to the melting temperature of the resin skin material, and this can be favorably interfacially fused by the heat retained by the sheet. In comparison with the case (1), a stable and strong laminate can be performed, and the heat can be effectively used.

Further, in the conventional press molding method, an expensive skin material is laid on the entire surface of the resin sheet due to the wrinkle extension, and it is necessary to consider the sheet pressing at the peripheral edge of the molding die by the holder of the pressing device, but this causes unnecessary loss of the trimming portion. Although it could not be avoided, since the skin material is firmly fused and held in advance to the resin sheet by the practice of the present invention, it can be carried out without planning to hold it by the blank holder, and the skin material is limited to around the necessary range of the product. Then you can stretch it. Therefore, the loss due to trimming can be minimized.

Further, in the present invention, by selecting a resin having compatibility between the mixed resin and the resin skin, or by using the same kind of the resin skin material as the highest melting point resin component and having compatibility, By performing the above-mentioned lamination with matching, the interface fusion between the resin skin material and the resin sheet can be made more sound and stronger. Moreover, the difficulty of temperature control for melting the mixed resin into a sheet and controlling the temperature of the resin sheet above the melting point of the resin skin material is eliminated, and the management work is made extremely easy.

Further, in the present invention, the mixed resin is formed into a sheet as described above, and while properly laminating the resin skin material (interfacial fusion), this is subjected to press molding at a predetermined temperature lowering point. That is, in the present invention, attention is paid to the fact that when the temperature of the mixed resin falls, solidification (crystallization) starts at a temperature lowering point lower than the melting point of the resin having the lowest melting point, and natural cooling or the like is performed without solidifying the laminated resin sheet as it is. A temperature lowering range is selected in which the resin sheet base material temperature is near the freezing point from the melting point of the lowest melting point resin component in the mixed resin while accelerating the temperature lowering, and the resin sheet is charged into the molding die and press-molded.

According to the present invention, press molding can be performed at a temperature sufficiently lower than the melting point of a skin material such as a non-woven fabric, and a laminated resin press-formed product in a very beautiful raised state without causing fatigue of the non-woven fabric or adhesion of the raised portion. In addition, it is possible to perform press molding at an appropriate molding temperature,
Sound shaping can be performed without impairing the physical properties of the laminated resin sheet. As a result, the press molding stabilizes the skin material implantation, strengthens the interfacial fusion, and makes it more stable.

Further, the mixed resin having a difference in melting point shows maximum specific heat near the freezing point lower than the melting point of the resin having the lowest melting point at the time of temperature decrease, and is most stable in terms of temperature, and it is difficult to cool. Therefore, by capturing this range and putting it into the mold and performing press molding, it is possible to shape the resin sheet soundly without a rapid temperature drop due to the cooling of the mold, and especially when the sheet surface is overheated. It effectively prevents the generation of cracks and rough skin upon cooling, and thus effectively prevents problems such as skin separation of the skin material and does not impair the napped state.

Further, as shown in the second invention, when the press molding die is charged, the temperature of the resin sheet is controlled by radiant heat from the surface opposite to the fusion surface of the resin skin material to maintain the above temperature range. In addition to preventing variations in input temperature, it effectively prevents thermal deterioration of the skin material and defective raising of hair, and at the same time uniformizes the resin sheet, which is the molding base, on its surface and core to cause molding defects due to temperature unevenness. Effectively prevent.

Embodiments Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

In the present invention, two or more kinds of mixed resins having sufficiently different melting points are used as the base material of the resin sheet. In view of the case where the mixed resin is three or more types, the resin component having the highest melting point by contrast is also called the highest melting point resin component even when it is two types, and the resin component having the lowest melting point by contrast is the lowest melting point resin component. Call.

The above-mentioned mixed resin is heated and melted at a temperature equal to or higher than the melting point of the highest melting point resin, extruded from the die 1 as shown in FIG. 1, and the extruded molten resin is passed between the sheet forming rolls 2 and 3 for surface forming and thickening. Make a sheet while doing. The resin sheet PS is further wound around the temperature control rolls 4 and 5, and the temperature is controlled so that the resin sheet PS is maintained at the melting point or higher of the resin skin material RS for lamination in a predetermined temperature control step TC ₁ .

Thus, as shown by the phantom line in the resin skin material RS, the temperature adjustment process is performed.
High temperature resin sheet PS between the sheet forming rolls 2 and 3 immediately before TC ₁
It is either sandwiched with or is guided to the temperature control roll 4 immediately after the sheet forming roll and stretched over the resin sheet PS, and while passing through the temperature control process TC ₁ , the resin cover material RS is retained by the heat retained by the resin sheet PS. Are melted and fused at their contact interfaces. The resin skin material RS is a non-woven fabric or other cloth, and is supplied in the form of a strip or a sheet cut into a certain size as shown in FIG.

The resin skin material RS is laid on the temperature control roll 4 so as to be on the inside of the resin sheet PS, and surface pressure is applied by the resin sheet PS from the outside in the mating surface area to carry out crimping while advancing the above-mentioned interfacial fusion. . Alternatively, the resin skin material RS is laid on the roll 4 so as to overlap the outer surface of the resin sheet PS, and pressure bonding and fusion bonding are performed. In the same crimping process, the skin material RS is fused to the anchor portion.

As an example of the composition of the mixed resin, an example of mixing a polypropylene resin component and a polyethylene resin component will be given. Polypropylene resin has a melting point of around 170 ° C, and polyethylene resin has a melting point of around 130 ° C, with the former being the highest melting point resin and the latter being the lowest melting point resin. Both resins are highly compatible and have a sufficient melting point difference.

It is preferable to use the same kind of polypropylene resin as the highest melting point resin as the resin skin material RS. As a result, the mixed resin PS and the resin skin material RS have compatibility with each other, and the melting points of the both are matched. As a result, the resin skin material RS has a high affinity with the resin sheet PS and is interface-fused to form a robust laminate. Further, the matching of the melting points makes it extremely easy to control the temperature for forming a sheet and the above-mentioned interfacial fusion, and helps optimize the temperature control.

In the present invention, as described above, it is proposed that the mixed resin contains a resin component of the same kind as the resin skin material as the highest melting point resin component, and as a suitable example, the highest melting point resin component and the resin skin material are polypropylene resin. Indicate the case.

In the case of the mixed resin of the polypropylene resin and the polyethylene resin, for example, in the range of 170 ° to 200 ° C., for example, 200 ° C. is melted to form a resin sheet, and a temperature control roll (pressure bonding roll) is 170 ° C. or higher, for example, a resin skin material. Laminates by promoting effective interfacial fusion at a temperature drop around 190 ° C, which is higher than the melting point.

In addition to the above as composition examples of two kinds of mixed resins, polyamide
An example is a mixed resin having compatibility with 66 (melting point 250 ° C.) and polyamide 6 (melting point 215 ° C.). Also when using this mixed resin, it is preferable to use polyamide 66 as the resin skin material RS.
The compatibility and the melting point are matched with each other, and the interfacial fusion is attempted at the melting point of the resin having the highest melting point or higher.

In each of the above composition examples, each resin component of the mixed resin has compatibility,
And the case where it has compatibility with the resin skin material RS is shown,
A resin having compatibility with the resin skin material RS is used for one of the mixed resins to provide compatibility between the mixed resin and the skin material RS, and as a suitable example, the mixed resin is composed of the highest melting point resin components of the same kind. .

When carrying out the present invention in each of the two types of composition examples, it does not prevent using a resin having a higher melting point than the highest melting point resin as the resin skin material RS, and according to the above, it is heated and melted at a temperature of the skin material or higher to form a sheet. The interface fusion is promoted at a temperature lower than the melting temperature and higher than the melting point of the skin material.

Further, as composition examples of three or more kinds of mixed resins, polypropylene resin, polyethylene resin and ethylene vinyl acetate resin (melting point 70 ° C to 97 ° C) mixing example, or polyamide 66, polyamide 6 and polyamide 12 (melting point 178 ° C) mixing example Indicates. Both composition examples show the case where three kinds of resins have compatibility, and according to the above, the above three kinds of mixed resins are melted at a melting point of polypropylene resin or polyamide 66 or more to interfacially melt the resin skin material RS with the heat retained by the resin sheet PS. To wear. In this case, by utilizing the fact that there are three or more kinds of mixed resins, the resin skin material RS has a melting point equal to or higher than the melting point of polypropylene resin or polyethylene resin which is a resin other than the lowest melting point resin (ethylene vinyl acetate resin) in the former composition example. Select those that have. Considering compatibility, a skin material made of polypropylene resin or a skin material made of polyethylene resin is preferably used. Similarly, in the latter composition example, polyamide 66 or polyamide 6 other than the lowest melting point resin (polyamide 12) is used.
It is recommended to use the same type of skin material as.

In the above example, when polyethylene resin or polyamide 6 is used as the skin material, the temperature control rolls 4 and 5 control the temperature of the resin sheet PS to be equal to or higher than the melting point of the polyethylene resin or polyamide 6, and retain the same resin sheet. Interface fusion is achieved by heat.

A resin sheet for interfacially bonding the resin skin material RS as described above
The PS is provided to the cutting unit 7 via the pinch roll 6 and cut into a unit length.

Next, convey each unit laminate resin sheet PS ′ to the conveyor 8
It is conveyed to the press device 10 by a and 8b, the temperature is promoted during this period, the temperature is lowered, the mold is put into the lower mold 11, and the upper mold 12 is immediately lowered to perform press molding. Lower mold
A suitable sheet feeder, for example, a vacuum feeder 14 is used for feeding into 11.

Then, the temperature near the freezing point is selected from the melting point of the resin having the lowest melting point in the mixed resin as the temperature lowering range, and the mold is charged.

That is, in the above composition example, in the mixed resin of polypropylene resin and polyethylene resin, the above-mentioned mold is charged in a temperature lowering range from a melting point of polyethylene resin having a low melting point of 130 ° C. to a freezing point of 125 ° C.,
Perform press molding. By the press molding, the resin skin material RS is fixed at the same time as shaping as a product to strengthen the bond.

Generally, two or more kinds of mixed resins having different melting points have a characteristic of starting solidification (crystallization) at a temperature lower than the melting point of the lowest melting point resin when the temperature is lowered, and exhibit maximum specific heat in the vicinity of the solidifying point from the melting point. In other words, having the maximum amount of heat and being in the coldest and most hateful state,
It also exhibits appropriate surface rigidity and stable heat retention, satisfying the optimum conditions for press molding.

The same applies to other composition examples, for example, even in the case of the mixed resin of the polypropylene resin, the polyethylene resin, and the ethylene vinyl acetate resin, the melting point of the ethylene vinyl acetate resin, which is the lowest melting point resin, starts to solidify at a temperature lower than 70 ° C. The solidification point is captured, the mold is put into the mold, and press molding is performed to shape and fix the skin material.

In press molding, it is indispensable to put a resin sheet in a mold and clamp the mold, and natural cooling during this period, in particular, supercooling at a contact surface with a lower mold remarkably impairs moldability. The present invention solves this problem as much as possible by setting the above conditions.

In order to secure the above temperature condition, as shown in FIGS. 1 and 2, the temperature control furnace 9 on the loading side to the press device 10 is arranged, and the unit laminate resin sheet PS ′ cut in the cutting section 7 is conveyed by the conveyor. At 8a, the temperature is adjusted such that the temperature of the resin sheet PS falls within the above-mentioned set temperature range in the temperature adjustment process TC ₂ during the introduction into the temperature adjustment furnace 9 and the conveyance in the furnace.

As the most preferable temperature control method, resin sheet as shown
The infrared heating device 15 is installed in a non-contact state so as to face the surface of the PS opposite to the surface laminated with the resin skin material RS, and only the resin sheet PS is heated by the radiant heat. On the other hand, the skin material
RS is heated at a lower ambient temperature in the furnace.

For example, in the case of the mixed resin of the polypropylene resin and the polyethylene resin, the resin sheet PS is heated to 125 ° C. by the radiant heat.
The skin material made of polypropylene resin is heated and kept warm so as to be close to it, and is kept warm by heating at an atmosphere temperature lower than this, for example, near 100 ° C. In this case, at least the introduction conveyor 8a uses a perforated belt having a large number of ventilation holes. Further, the outlet conveyor 8b has one end inside the furnace and the other end extended to the side of the press machine arranged at the furnace outlet, and temperature-controlled unit laminated resin sheet P by speed switching.
The S'is fed to the press machine at a faster rate.

As shown in FIG. 4, the unit laminate resin sheet PS '
As described above, the resin skin material RS is firmly held on the surface of the resin sheet PS by the interfacial fusion layer RS ', which is advantageous in adsorbing by the vacuum feeder 14 or the like and putting in the mold.

Further, paying attention to the above-mentioned interface fusion effect, the resin skin material RS is not stretched over the ear portion (trimmed portion) which is the unnecessary portion of the resin sheet PS, and is kept within a range that covers a necessary portion that becomes a product as much as possible. E indicates a non-tensioned cloth portion of the resin skin material RS. Resin skin material
When RS is made into a unit sheet and stretched on the surface of the resin sheet PS for interfacial fusion, the non-stretched fabric portion E can be formed around the necessary portion.

As shown in FIG. 3, the non-tensioned cloth portion E is placed on the upper surface of the blank holder 13 when it is put into the press machine, and the upper mold is held during mold clamping.
Consider only wrinkle suppression of the pressing resin sheet PS between 12 and. This makes it possible to minimize the loss of expensive resin skin material.

As described above, extrusion of molten resin, formation of a belt-like sheet, lamination by interfacial fusion of resin skin material, and press molding are all performed consistently, and a laminated resin press-formed product with beautiful raised hair is continuously produced. is there.

EFFECTS OF THE INVENTION As described above, according to the present invention, the heat of the resin sheet of the mixed resin can be used to firmly bond the laminate skin material, and the heat retention state of the resin sheet at the time of temperature decrease and the laminate fusion can be achieved. Appropriate press molding can be performed by utilizing the attached state, and mixed resin can be made into a resin sheet, resin skin material can be pressure-bonded and interface-fused, and the laminated resin sheet can be press-formed reasonably in integrated production. .

That is, according to the present invention, while processing the mixed resin into a resin sheet, the temperature can be adjusted to the melting temperature of the resin skin material and the interface heat can be satisfactorily fused by the heat retained by the sheet. Compared with the case of (effect), stable and strong lamination can be performed, and thus effective use of heat can be achieved.

Further, in the conventional press molding method, an expensive skin material is laid over the entire surface of the resin sheet due to the wrinkle extension, and it is necessary to consider the pressing of the sheet on the peripheral edge of the molding side by the holder of the pressing device, but this causes unnecessary loss of the trimming portion. Although it could not be avoided, since the skin material can be subjected to press molding in a state where it is firmly fused and held to the resin sheet beforehand by the implementation of the present invention, it can be carried out without planning the holding by the blank holder, and the skin material Can be stretched only around the required range of the product. Therefore, the loss due to trimming can be minimized.

Further, in the present invention, by selecting a resin having compatibility between the mixed resin and the resin skin material, or by using the same kind of the resin skin material as the highest melting point resin, the compatibility and the melting point are matched, By performing the above lamination,
The interface fusion between the resin skin material and the resin sheet can be made more sound and stronger. Moreover, the difficulty of temperature control for melting the mixed resin into a sheet and controlling the temperature of the resin sheet above the melting point of the resin skin material is eliminated,
The management work will be extremely easy.

Further, in the present invention, when the temperature of the mixed resin drops, attention is paid to the fact that solidification (crystallization) starts at a temperature lowering point lower than the melting point of the resin having the lowest melting point, and the resin sheet matrix is promoted while promoting the temperature lowering accompanied by natural cooling and the like. The temperature is selected from the melting point of the lowest melting point resin in the mixed resin to the vicinity of the freezing point, and the temperature is appropriately charged into the mold and press-molded.

According to the present invention, press molding can be performed at a temperature sufficiently lower than the melting point of a skin material such as a non-woven fabric, and a laminated resin press-formed product in a very beautiful raised state without causing fatigue of the non-woven fabric or adhesion of the raised portion. In addition, it is possible to perform press molding at an appropriate molding temperature,
Sound shaping can be performed without impairing the physical properties of the resin sheet in a laminated state. In addition, the press molding makes the planting of the skin material more stable.

Further, the mixed resin having a difference in melting point exhibits maximum specific heat near the freezing point lower than the melting point of the lowest melting point resin at the time of temperature decrease, and is most stable in temperature and cooled. Therefore, by capturing this range and putting it into the mold and performing press molding, it is possible to shape the resin sheet soundly without a rapid temperature drop due to the cooling of the mold, and especially when the sheet surface is overheated. It effectively prevents the generation of cracks and rough skin upon cooling, and thus effectively prevents problems such as skin separation of the skin material and does not impair the napped state.

Further, as shown in the second invention, when the press molding die is charged, the temperature of the resin sheet is controlled by radiant heat from the surface opposite to the fusion surface of the resin skin material to maintain the above temperature range. In addition to preventing variations in input temperature, it effectively prevents thermal deterioration of the skin material and defective raising of hair, and at the same time uniformizes the resin sheet, which is the molding base, on its surface and core to cause molding defects due to temperature unevenness. Can be effectively prevented. By the above, it is possible to perform the production process from molding of molten resin sheet to laminating of resin skin material and press molding in a consistent continuous line, improving productivity, reducing costs and improving the quality of laminated resin products. It can achieve the purpose.

[Brief description of drawings]

FIG. 1 is a side view schematically showing a laminated resin press-molded product manufacturing apparatus for explaining an embodiment of the present invention, FIG. 2 is a plan view of the same, and FIG. 3 shows a state in which a unit laminate resin sheet is put into a molding die. FIG. 4 is a cross-sectional view of the pressing device, and FIG. 4 is an enlarged cross-sectional view illustrating a state in which the resin skin material is interface-fused to the resin sheet. 1 ...... die, 2,3 ...... sheeting rolls, 4,5 ...... temperature regulation rolls, 9 ...... furnace, TC _1, TC ₂ ...... temperature control stroke, 10 ...... press apparatus, 11 ...... under Mold, 12 …… upper mold, PS …… resin sheet, RS …… resin skin material, PS ′ …… unit laminated resin sheet.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B29L 9:00

Claims (6)

[Claims] 1. A resin sheet melted at a temperature equal to or higher than a melting point of a resin having a highest melting point in a mixed resin of two or more kinds and formed into a sheet, and the temperature is adjusted to a temperature equal to or higher than a melting point of a resin skin material, and a resin skin material is provided on a surface of the resin sheet. Is applied to promote the interfacial fusion of the resin skin material to the same sheet by the heat retained by the sheet, and the resin sheet for interfacial fusion of the resin skin material is formed from the melting point of the lowest melting point resin component in the mixed resin A method for producing a laminated resin press-formed product, which comprises performing press-forming by introducing the material into a molding die in a temperature-falling range in the vicinity. 2. The method for producing a laminated resin press-formed product according to claim 1, wherein the mixed resin contains a resin component of the same type as the resin skin material as a resin component having the highest melting point. 3. The method for producing a laminated resin press-formed product according to claim 1, wherein the resin skin material and the mixed resin are compatible with each other. 4. A laminate resin press-formed product according to claim 1, wherein the mixed resin contains a polypropylene resin as the highest melting point resin component and a polyethylene resin as the lowest melting point resin component. Law. 5. The method for producing a laminate resin press-formed product according to claim 4, wherein the skin material is a polypropylene resin of the same type as that of the resin having the highest melting point. 6. A resin sheet melted at a temperature equal to or higher than a melting point of a resin having a highest melting point in a mixed resin of two or more kinds and formed into a sheet, and the temperature is adjusted to a temperature equal to or higher than a melting point of the resin skin material, and a resin skin material is provided on a surface of the resin sheet. From the surface opposite to the interfacial-fusing surface, by promoting the interfacial fusion of the resin skin material to the same resin sheet by the heat retained by the resin sheet, Laminated resin characterized in that the temperature of the resin sheet is controlled by radiant heat so as to be maintained in a temperature lowering range near the freezing point from the melting point of the lowest melting point resin, and after the temperature is controlled, the resin sheet is charged into a molding die for press molding. Manufacturing method of press-molded products.