JP6779095B2 - Manufacturing method of shaping decorative sheet - Google Patents

Description

The present invention relates to a method for producing a shaped decorative sheet, a method for producing a shaped decorative sheet, a molded product, and a molded product.

The insert molding method and the in-mold molding method are used as a technique for decorating a molded body such as a vehicle interior material or a home appliance housing. In these methods, a decorative molded body having a decoration can be manufactured by integrally molding a decorative sheet for decoration including a printing layer and a housing (injection resin).
Patent Document 1 discloses a mold for in-mold molding provided with a specific heating device, a method for manufacturing a molded product using the mold, and the like.

Japanese Unexamined Patent Publication No. 2008-94038

In order to prevent the design surface of the decorative sheet from being scratched or peeled off, the design surface of the decorative sheet is generally arranged not on the outermost surface of the molded body but on the side in contact with the housing (molding resin). However, when the molded product is manufactured, the design surface of the decorative sheet is arranged on the side where the molding resin is injected, so that the molten molding resin and the printing layer of the decorative sheet come into contact with each other and the design property is impaired. There was a problem that a phenomenon (hereinafter referred to as "ink flow phenomenon") occurred.
An object of the present invention is to provide a method for producing a shaped decorative sheet, a method for producing a shaped decorative sheet and a molded product, which can prevent or reduce the ink flow phenomenon.

As a result of investigating the cause of the ink flow phenomenon, the present inventors have found that the cause is that the decorative sheet itself is melted by the heat of the molten molding resin.
As a result of diligent studies based on the above findings, the present inventors have prevented the decorative sheet from melting by improving the heat resistance of the decorative sheet, particularly the heat resistance of the surface of the base material layer on the print layer side. , The present invention has been completed by finding that the ink flow phenomenon can be suppressed.
According to the present invention, the following methods for manufacturing a shaping decorative sheet and the like are provided.
1. 1. A step of heating a decorative sheet including a base material layer and a printing layer, a step of heating the decorative sheet by a heating means installed so as to face the surface of the decorative sheet on the print layer side, and a step of heating the decorative sheet. A method for producing a shaped decorative sheet, which comprises a step of shaping the decorative sheet after heating.
2. The method for producing a shaped decorative sheet according to 1, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the base material layer on the print layer side of the decorative sheet is 130 ° C. to 170 ° C.
3. 3. 1. Describe 1 or 2 in which, in the step of heating the decorative sheet, the decorative sheet is heated by the heating means installed so as to face the surface of the decorative sheet on the base material layer side in addition to the heating means. How to manufacture a shaped decorative sheet.
4. 3. The method for producing a shaped decorative sheet according to 3, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the decorative sheet opposite to the printing layer of the base material layer is 130 ° C to 170 ° C. ..
5. The method for producing a shaped decorative sheet according to any one of 1 to 4, wherein the shaping is performed by one or more methods selected from vacuum forming, compressed air forming, vacuum forming, press molding and plug assist molding.
6. The method for producing a shaped decorative sheet according to any one of 1 to 5, wherein the base material layer contains polypropylene.
7. The method for producing a shaped decorative sheet according to 6, wherein the crystallization rate of polypropylene of the base material layer at 130 ° C. before heating is 2.5 min ^-1 or less.
8. The method for producing an excipient decorative sheet according to 6 or 7, wherein the polypropylene isotactic pentat fraction of the base material layer before heating is 85 mol% to 99 mol%.
9. The method for producing a shaped decorative sheet according to any one of 6 to 8, wherein the polypropylene of the base material layer before heating contains smetica crystals.
10. The shaping addition according to any one of 6 to 9, wherein the polypropylene of the base material layer before heating has an exothermic peak of 1 J / g or more on the low temperature side of the maximum endothermic peak in the curve obtained by differential scanning calorimetry. How to make a decorative sheet.
11. A shaping decorative sheet containing a base material layer and a printing layer.
A shaping decorative sheet having a crystallinity of 55% or more on the surface of the base material layer on the printing layer side.
12. A shaping decorative sheet containing a base material layer and a printing layer.
A shaping decorative sheet in which the difference between the crystallinity of the surface of the base material layer on the printing layer side and the crystallinity of the surface of the base material layer opposite to the printing layer is within 10%.
13. 11. The shaping decorative sheet according to 11 or 12, wherein the haze value of the base material layer is 15% or less.
14. The shaping decorative sheet according to any one of 11 to 13, which does not contain a nucleating agent.
15. The shaping decorative sheet according to any one of 11 to 14, wherein the base material layer contains polypropylene.
16. The shaping decorative sheet according to 15, wherein the crystallization rate of polypropylene in the base material layer at 130 ° C. is 2.5 min ^-1 or less.
A step of manufacturing a shaped decorative sheet by the method for manufacturing a shaped decorative sheet according to any one of 17.1 to 9.
The step of mounting the shaping decorative sheet in the first mold,
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. A method for manufacturing a molded product, which comprises a step of integrating the shaped decorative sheet and the molding resin.
18. The step of mounting the shaping decorative sheet according to any one of 1 to 16 into the first mold.
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. A method for manufacturing a molded product, which comprises a step of integrating the shaped decorative sheet and the molding resin.
19. A step of heating a decorative sheet including a base material layer and a printing layer, wherein the decorative sheet is heated by a heating means installed so as to face the surface of the decorative sheet on the printing layer side.
The step of cooling the heated decorative sheet to room temperature and arranging it on the first mold.
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. The process of integrating the decorative sheet and the molding resin,
A method for producing a molded product including.
20. 19. The method for producing a molded product according to 19, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the base material layer on the print layer side of the decorative sheet is 130 ° C. to 170 ° C.
21. 19 or 20, wherein in the step of heating the decorative sheet, the decorative sheet is heated by the heating means installed so as to face the surface of the decorative sheet on the base material layer side in addition to the heating means. Method of manufacturing a molded product.
22. 21. The method for producing a molded product according to 21, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the decorative sheet opposite to the printing layer of the base material layer is 130 ° C. to 170 ° C.
A molded product produced by using the shaping decorative sheet according to any one of 23.11 to 16.

According to the present invention, it is possible to provide a method for producing a shaped decorative sheet, a method for manufacturing a shaped decorative sheet and a molded product, which can prevent or reduce the ink flow phenomenon.

It is the schematic of the decorative sheet used in the manufacturing method of the shaped decorative sheet of this invention. It is a figure which shows one Embodiment of the manufacturing method of the shaping decorative sheet of this invention. It is a figure which shows one Embodiment of the manufacturing method of the shaping decorative sheet of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is a figure which shows one Embodiment of the manufacturing method of the molded article of this invention. It is the schematic of the apparatus used for manufacturing the polypropylene sheet (base material layer) in Example 1. FIG.

[Manufacturing method of shaping decorative sheet]
The method for producing a shaped decorative sheet of the present invention is a step of heating a decorative sheet including a base material layer and a printing layer, and is heated so as to face the surface of the decorative sheet on the printing layer side. It includes a step of heating the decorative sheet by means and a step of shaping the decorative sheet after heating.
In the specification of the present application, the "face on the printing layer side of the decorative sheet (or the shaping decorative sheet)" is the surface formed by the printing layer on the upper and lower surfaces of the decorative sheet (or the shaping decorative sheet). Or, the surface closer to the printing layer than the base material layer, and the "surface on the base material layer side of the decorative sheet (or the shaped decorative sheet)" is the decorative sheet (or the shaped decorative sheet). Of the upper and lower surfaces, the surface formed by the base material layer or the surface closer to the base material layer than the printed layer.
In addition, the drawings are schematic, and the ratio of each dimension is different from the actual one.
Hereinafter, each member and each process used in the present invention will be described.

(Decorative sheet)
The decorative sheet is a sheet for decorating a molded body used as an interior material of a vehicle or a housing of a home appliance to give it a design.
The decorative sheet usually includes a base material layer and a printing layer, and the printing layer is provided with a desired pattern, characters, colors, and the like. By integrating the decorative sheet and the molding resin, it is possible to manufacture a molded product having the design of the printing layer.
An embodiment of the decorative sheet is shown in FIG. The decorative sheet 1 has a laminated structure of a base material layer 10 and a printing layer 20.

The material used for the base material layer is not particularly limited, but is usually a crystalline resin, and for example, polyolefin can be used.
Examples of the polyolefin include polyethylene, polypropylene, and cyclic polyolefin resin, and polypropylene is particularly preferable from the viewpoint of heat resistance and hardness.

Polypropylene is a polymer containing at least structural units derived from propylene. Specific examples thereof include homopolypropylene and propylene and copolymers of other olefins (ethylene and the like). It may be a mixture in which a polyolefin such as polyethylene or a copolymer is mixed with polypropylene.
The polypropylene copolymer may be random polypropylene or block polypropylene, or a mixture thereof.
These may be used individually by 1 type or in combination of 2 or more type.

If necessary, polypropylene may contain additives such as pigments, antioxidants, stabilizers, and UV absorbers.
Further, a polyolefin such as polypropylene or polyethylene is modified with a modification compound such as maleic anhydride, dimethyl maleate, diethyl maleate, acrylic acid, methacrylic acid, tetrahydrophthalic acid, glycidyl methacrylate, hydroxyethyl methacrylate, or methyl methacrylate. The modified polyolefin resin thus obtained may be blended.

When polypropylene is used as the base material layer, it is preferable that polypropylene contains smethica crystals before the heat treatment described later.
Polypropylene is a crystalline resin and can take a crystalline form such as α crystal, β crystal, γ crystal, and smetica crystal. Of these crystal forms, smetica crystals can be produced as intermediates between amorphous and crystalline by cooling polypropylene from a molten state at a rate of 80 ° C. or higher per second. Smetica crystals are not a stable structure with a regular structure like crystals, but a metastable structure with fine structures gathered together. Therefore, the interaction between the molecular chains is weak, and it has a property of being easily softened when heated as compared with α crystals having a stable structure.
The crystal structure of polypropylene is measured by the method described in Examples.

Further, it is preferable that the base material layer does not contain a nucleating agent. Even when it is contained, the content of the nucleating agent in the base material layer is 1.0% by mass or less, preferably 0.5% by mass or less.
Examples of the nucleating agent include a sorbitol-based crystal nucleating agent and the like, and examples of commercially available products include Gelol MD (Shin Nihon Rikagaku Co., Ltd.) and Riquemaster FC-1 (RIKEN Vitamin Co., Ltd.).

To make polypropylene, which is a crystalline resin transparent, for example, a method of forming a smetica crystal by cooling at 80 ° C./sec or higher during the production of a base material layer and a method of forcibly forming fine crystals by adding a nucleating agent. There is a way to make it. The nucleating agent increases the crystallization rate of polypropylene to more than 2.5 min ^-1, and by generating and filling a large number of crystals, it eliminates the space for physical growth and reduces the size of the crystals. There is. However, since the nucleating agent has a core substance, it is slightly whitish even if it becomes transparent, so that the design property may be deteriorated.

Therefore, by setting the crystallization rate of polypropylene to 2.5 min ^-1 or less without adding a nucleating agent and cooling at 80 ° C./sec or more to form smetica crystals, a laminate with excellent design can be obtained. Can be done. Further, when shaped after heating, which will be described later, the base material layer is transferred to α crystals while maintaining the microstructure derived from Smetica crystals. By this transition, the surface hardness and transparency can be further improved.

The polypropylene of the base material layer is preferably polypropylene having an isotactic pendat fraction of 85 mol% to 99 mol% from the viewpoint of scratch resistance.
The isotactic pentad fraction is an isotactic fraction in a pentad unit (five consecutive isotactic bonds of five propylene monomers) in a molecular chain.
The isotactic pentat fraction of polypropylene is preferably 85 mol% to 99 mol%, more preferably 90 mol% or more. If the isotactic pentat fraction is less than 85 mol%, the surface hardness is inferior, and the surface of the laminate may be scratched to spoil the appearance.
On the other hand, polypropylene having a high isopentat fraction has a high crystallinity, so a method such as adding a nucleating agent or cooling at a rate of 80 ° C./sec or higher must be used when manufacturing the sheet described later. , May result in an opaque sheet.
The isotactic pendat fraction is measured by the method described in Examples.

Preferably the crystallization rate of the polypropylene used in the base layer (130 ° C.) is at 2.5 min ^-1 or less, more preferably 2.0Min ^-1 or less. The crystallization rate is measured by the method described in Examples.
The crystallization rate of polypropylene does not change before and after the heat treatment described later.

Further, before the heat treatment described later, the polypropylene of the base material layer has an exothermic peak of 1.0 J / g or more, preferably 1.5 J / g or more on the low temperature side of the maximum endothermic peak in the differential scanning calorimetry curve. ..

The thickness of the base material layer is usually 50 to 500 μm.
The base material layer can be produced by the method described in Examples.

The printing layer is a layer for expressing a pattern, characters, colors, and the like, and may be formed on a part of the base material layer or may be formed on the entire surface. The form of the pattern or the like is not particularly limited, and various forms such as solid, carbon-like, and wood-grain-like can be used.

The printing layer can be formed by printing a desired pattern or the like on the base material layer.
As a printing method, general printing methods such as a screen printing method, an offset printing method, a gravure printing method, a roll coating method, a spray coating method, and an inkjet method can be used. In particular, the screen printing method is preferable because the ink film thickness can be increased and ink cracking is unlikely to occur when the ink is formed into a complicated shape.
For example, in the case of screen printing, an ink having excellent elongation during molding is preferable, and examples thereof include "FM3107 high density white" and "SIM3207 high density white" manufactured by Jujo Chemical Co., Ltd., but this is not the case.

The thickness of the print layer is usually 1 to 50 μm.

A binder layer may be included on the surface of the printing layer opposite to the base material layer. The binder layer can improve the adhesiveness between the decorative sheet and the molding resin described later.
The material used for the binder layer is not particularly limited, but for example, polyolefin can be used. The polyolefin is as described above.
The thickness of the binder layer is usually 5 to 50 μm.
The binder layer can be laminated by printing on the surface of the printing layer opposite to the base material layer.

(Other layers)
In addition to the above layers, the decorative sheet may include a hard coat layer to increase hardness. The hard coat layer is usually formed by applying it to the surface of the base material layer opposite to the printed layer.

(Heating process)
In manufacturing the shaping decorative sheet, first, the above-mentioned decorative sheet is heat-treated. The heat treatment is performed by using at least a heating means installed so as to face the surface of the decorative sheet on the print layer side (hereinafter, may be referred to as a "first heating means").
An embodiment of this step is shown in FIG. The first heating means 100 is installed at a position facing the surface of the decorative sheet 1 on the print layer 20 side (upper in FIG. 2), and the decorative sheet 1 is heated by the first heating means 100.

By intensively heating from the surface of the decorative sheet on the print layer side by the above heat treatment, the crystallinity of the surface of the base material layer on the print layer side can be increased and the heat resistance can be improved. As a result, the ink flow phenomenon can be suppressed at the time of integration with the molding resin described later.

The heating method by the first heating means may be direct heating or indirect heating. In the case of direct heating, for example, hot plate heating can be performed, and in the case of indirect heating, an infrared heater or the like can be used.
The heating by the first heating means is preferably carried out under the condition that the surface temperature of the surface of the base material layer on the print layer side is 130 ° C. to 170 ° C., preferably 150 to 170 ° C.

In addition to the first heating means, the decorative sheet is provided by using a heating means (hereinafter, may be referred to as a "second heating means") installed so as to face the surface of the decorative sheet on the base material layer side. May be heated.
The embodiment is shown in FIG. A second heating means 110 is installed at a position (lower in FIG. 3) facing the surface of the decorative sheet 1 on the base material layer 10 side, and the decorative sheet 1 is heated by the second heating means 110.

By using the second heating means in addition to the first heating means, it is possible to obtain a shaped decorative sheet having excellent surface hardness and chemical resistance in addition to heat resistance.
The specific example of the second heating means and the heating time are the same as those of the first heating means. The heating by the second heating means is preferably carried out under the condition that the sheet surface temperature of the surface of the base material layer opposite to the printing layer is 130 ° C. to 170 ° C., preferably 150 to 170 ° C.

The heating method of the decorative sheet is not particularly limited as long as the above conditions are satisfied. For example, heating may be performed once for each decorative sheet to be shaped, a continuous vertically elongated decorative sheet may be moved so as to pass in the vicinity of the first heating means, or the first heating may be performed. It may be continuously heated by moving it so as to pass between the means and the second heating means.

(Shaping process)
After performing the above heat treatment, the decorative sheet is shaped. The shaping means processing the decorative sheet into a desired shape, and for example, it can be shaped into a shape that matches the uneven shape in the first mold described later.
The shaping method is not particularly limited, but one or more methods selected from vacuum forming, compressed air forming, vacuum pressurized air forming, press forming and plug assist forming can be performed.

[Excipient decoration sheet]
The first shaping decorative sheet of the present invention includes a base material layer and a printing layer, and the crystallinity of the surface of the base material layer on the printing layer side is 55% or more. The crystallinity of the surface of the base material layer on the print layer side is preferably 60% or more. The crystallinity is measured by the method described in Examples.

In the first shaping decorative sheet, the crystallinity of the surface of the base material layer opposite to the printed layer is not particularly limited, but is usually 30% or more, preferably 40% or more, more preferably. It is 50% or more.
A high degree of crystallinity on the surface of the base material layer opposite to the printed layer side is preferable from the viewpoint of surface hardness and chemical resistance.

In the second shaping decorative sheet of the present invention, the difference between the crystallinity of the surface of the base material layer on the print layer side and the crystallinity of the surface of the base material layer opposite to the print layer is 10% or less. is there. The difference in crystallinity is preferably 5% or less.

In the second shaping decorative sheet of the present invention, the crystallinity of the surface of the base material layer on the print layer side is preferably 40% or more, more preferably 50% or more, still more preferably 60% or more. Is. The crystallinity of the surface of the base material layer opposite to the printed layer is preferably 40% or more, more preferably 50% or more, and further preferably 60% or more.

In the first and second shaped decorative sheets of the present invention, the haze value of the base material layer is preferably 15% or less, more preferably 10% or less. The haze value is measured by the method described in Examples.

The first and second excipient decorative sheets of the present invention preferably do not contain a nucleating agent. Even when it is contained, the content of the nucleating agent in the base material layer is 1.0% by mass or less, preferably 0.5% by mass or less.
The nucleating agent is as described above.

When polypropylene is used as the base material layer, the first and second shaping decorative sheets of the present invention preferably have a crystallization rate (130 ° C.) of 2.5 min ^-1 or less, and 2.0 min ^-1 or less. Is more preferable. The crystallization rate is measured by the method described in Examples.

Further, by calculating the scattering intensity distribution and the long period by the small-angle X-ray scattering analysis method, it is possible to determine whether the base material layer is obtained by cooling at 80 ° C./sec or more, or not. That is, it is possible to determine whether or not the base material layer has a fine structure derived from Smetica crystals by the above analysis. The measurement is performed under the following conditions.
-The X-ray generator uses ultraX 18HF (manufactured by Rigaku Co., Ltd.), and an imaging plate is used to detect scattering.
-Light source wavelength: 0.154 nm
・ Voltage / current: 50kV / 250mA
・ Irradiation time: 60min
・ Camera length: 1.085mm
-Stack the sheets so that the sample thickness is 1.5 to 2.0 mm. Stack the sheets so that the film formation (MD) directions are aligned.

The shaped decorative sheet of the present invention can be manufactured by the above-mentioned manufacturing method of the shaped decorative sheet. The configuration of each layer of the shaped decorative sheet is the same as that described in the above-described method for manufacturing the shaped decorative sheet.

[Method for manufacturing the first molded product]
The first method for manufacturing a molded product of the present invention is a step of manufacturing a shaped decorative sheet by the above-mentioned manufacturing method of a shaped decorative sheet, and a step of mounting the shaped decorative sheet in the first mold. , The process of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold to perform shaping. Includes a step of integrating the decorative sheet and the molding resin.
The above-mentioned shaping decoration sheet of the present invention may be used instead of the shaping decoration sheet obtained by the above-mentioned manufacturing method of the shaping decoration sheet.
Hereinafter, one embodiment of each step will be described with reference to the drawings.

(Manufacturing process of shaping decorative sheet)
In this step, the shaped decorative sheet is manufactured by the method for manufacturing the shaped decorative sheet of the present invention described above. As shown in FIG. 4, it is preferable to shape the shaping decorative sheet 201 so as to match the concave shape of the first mold 210.

(Molding process)
In this step, the shaping decorative sheet 201 is mounted in the first mold 210, and the second mold 220 facing the first mold 210 is combined with the first mold 210 for mold clamping. Do (Fig. 5).

(Supply process of molding resin)
In this step, the molding resin 222 is supplied from the injection port provided in the second mold 220 to the hollow portion formed inside the first mold 210 and the second mold 220, and shaped. The decorative sheet 201 and the molding resin 222 are integrated.
The molding resin is not particularly limited, but for example, polyolefin can be used. The polyolefin is as described above.

After supplying the molding resin 222 and cooling it for a certain period of time, the molded body 230 is obtained by opening the first mold 210 and the second mold 220.

[Method for manufacturing the second molded product]
The second method for producing a molded product of the present invention is a step of heating a decorative sheet including a base material layer and a printing layer, and the heating is installed so as to face the surface of the decorative sheet on the printing layer side. A step of heating the decorative sheet by means, a step of arranging the heated decorative sheet on the first mold, and fastening the first mold and the second mold facing the first mold. The process includes a step of supplying a molding resin from an injection port provided in the second mold, and a step of integrating the decorative sheet and the molding resin.
Hereinafter, one embodiment of each step will be described with reference to the drawings.

(Heating process of decorative sheet)
In manufacturing the molded product, first, the decorative sheet 1 is heat-treated (FIG. 8). The decorative sheet 1 is as described above.
The heat treatment of the decorative sheet 1 is performed by using at least a heating means 310 (hereinafter, may be referred to as a “first heating means”) 310 installed so as to face the surface of the decorative sheet 1 on the print layer side. .. The first heating means 310 and the heating conditions are the same as those of the first heating means in the above-described method for producing a shaping decorative sheet of the present invention.

By intensively heating from the surface of the decorative sheet on the print layer side by the above heat treatment, the crystallinity of the surface of the base material layer on the print layer side can be increased and the heat resistance can be improved. As a result, the ink flow phenomenon can be suppressed at the time of integration with the molding resin described later.

In addition to the first heating means 310, a heating means 312 (hereinafter, may be referred to as a "second heating means") installed so as to face the surface of the decorative sheet 1 on the base material layer side is used. The decorative sheet 1 may be heated (FIG. 9).

By using the second heating means 312 in addition to the first heating means 310, it is possible to obtain a decorative sheet having excellent surface hardness and chemical resistance in addition to heat resistance.
The second heating means 312 and the heating conditions are the same as those of the second heating means in the above-described method for producing the shaping decorative sheet of the present invention.

(Process of arranging the decorative sheet on the first mold, mold clamping process)
Next, the heat-treated decorative sheet 1 is cooled to room temperature and placed on the first mold 320. The method of arrangement is not particularly limited, but usually, the decorative sheet 1 is arranged so as to cover a part or all of the cavity of the first mold 320 (FIG. 10).
After arranging the decorative sheet 1, the second mold 330 facing the first mold 320 is combined with the first mold 320 to perform mold clamping.

(Supply process of molding resin)
In this step, the molding resin 332 is supplied from the injection port provided in the second mold 330, and the decorative sheet 1 and the molding resin 332 are integrated (FIG. 11).
After the molding resin 332 is supplied and cooled for a certain period of time, the molded body 340 is obtained by opening the first mold 320 and the second mold 330 (FIG. 12).

[Molded product]
The molded product of the present invention can be produced by using the above-mentioned shaping decorative sheet of the present invention. In addition, the molded product of the present invention can be produced by the above-mentioned method for producing the first and second molded products of the present invention.
The molded body of the present invention can be used for vehicle interior materials, exterior materials, housings for home appliances, decorative steel plates, decorative plates, housing equipment, housings for information and communication equipment, and the like.

Example 1
[Manufacturing of shaped decorative sheets]
A polypropylene sheet (base material layer) 51 was manufactured using the manufacturing apparatus shown in FIG.
The operation of the device will be described. The molten resin (polypropylene) extruded from the T-die 52 of the extruder is sandwiched between the metal endless belt 57 and the fourth cooling roll 56 on the first cooling roll 53. In this state, the molten resin is pressure-welded with the first and fourth cooling rolls 53 and 56 and rapidly cooled. The polypropylene sheet is subsequently sandwiched between the metal endless belt 57 and the fourth cooling roll 56 at an arc portion corresponding to substantially the lower half circumference of the fourth cooling roll 56 and surface-pressed. After surface pressure welding and cooling with the fourth cooling roll 56, the polypropylene sheet in close contact with the metal endless belt 57 is moved onto the second cooling roll 54 with the rotation of the metal endless belt 57. Similar to the above, the polypropylene sheet is planarly pressure-welded by a metal endless belt 57 at an arc portion corresponding to substantially the upper half circumference of the second cooling roll 54, and is cooled again. The polypropylene sheet cooled on the second cooling roll 54 is then peeled off from the metal endless belt 57. The surfaces of the first and second cooling rolls 53 and 54 are coated with an elastic material 62 made of nitrile-butadiene rubber (NBR).

The manufacturing conditions of the polypropylene sheet (base material layer) 51 are as follows.
・ Extruder diameter: 90 mm
-Width of T-die 52: 800 mm
-Polypropylene (PP): Product name "Prime Polypro F-133A" (manufactured by Prime Polymer Co., Ltd. (melt flow index 2.8 g / 10 min, homopolypropylene))
-Pick-up speed of polypropylene sheet 51: 6 m / min
-Surface temperature of the fourth cooling roll 56 and the metal endless belt 57: 14 ° C.
-Sheet thickness: 220 μm
・ Sheet haze value: 9.7%

The obtained polypropylene sheet was evaluated as follows.

[Measurement of isotactic pendat fraction]
The isotactic pendat fraction was measured by evaluating the ¹³ C-NMR spectrum of the obtained polypropylene. Specifically, the measurement of the isotactic pendat fraction is carried out according to the following devices and conditions according to the peak attribution proposed in "Macromomolecules, 8, 687 (1975)" by A. Zambali et al. And the calculation formula was used.
[Device / Conditions]
Equipment: JNM-EX400 type ¹³ C-NMR equipment manufactured by JEOL Ltd. Method: Proton complete decoupling method Concentration: 220 mg / ml
Solvent: 90:10 (volume ratio) mixed solvent of 1,2,4-trichlorobenzene and heavy benzene Temperature: 130 ° C
Pulse width: 45 °
Pulse repetition time: 4 seconds Integration: 10000 times [Calculation formula]
Isotactic pendat fraction [mmmm] = m / S x 100
S: Signal intensity of side chain methyl carbon atom of all propylene units m: Mesopentad chain: 21.7 to 22.5 ppm
The isotactic pendat fraction of the obtained polypropylene sheet was 98%.

[Measurement of crystallization rate]
The crystallization rate was measured using a differential scanning calorimetry device (DSC) (product name "Diamond DSC", manufactured by PerkinElmer). Specifically, polypropylene is heated at 10 ° C./min from 50 ° C. to 230 ° C., held at 230 ° C. for 5 minutes, cooled at 80 ° C./min from 230 ° C. to 130 ° C., and then to 130 ° C. It was retained and crystallized. Measurement of the change in calorific value was started from the time when the temperature reached 130 ° C., and a DSC curve was obtained. From the obtained DSC curve, the crystallization rate was determined by the following procedures (i) to (iv).
(I) The baseline was the linear approximation of the change in calorific value from the time point 10 times the time from the start of measurement to the peak top to the time point 20 times.
(Ii) The intersection of the tangent line with the slope at the inflection point of the peak and the baseline was obtained, and the crystallization start and end times were obtained.
(Iii) The time from the obtained crystallization start time to the peak top was measured as the crystallization time.
(Iv) The crystallization rate was determined from the reciprocal of the obtained crystallization time.
The crystallization rate of the obtained polypropylene sheet was 0.1 min ^-1 .

[Confirmation of crystal structure]
The crystal structure of polypropylene was described in T.I. It was confirmed by wide-angle X-ray diffraction (WAXD: Wide-Angle X-ray Diffraction) with reference to the method used by Konishi et al. (Macromopolymers, 38,8749,2005).
In the analysis, the peaks of the amorphous phase, the intermediate phase, and the crystalline phase were separated from each other for the X-ray diffraction profile, and the abundance ratio was determined from the peak area assigned to each phase.
It was confirmed that the obtained polypropylene sheet had Smetica crystals.

[Differential scanning calorimetry]
The differential scanning calorimetry was performed on the obtained polypropylene sheet. As the differential scanning calorimetry device, the same device as in [Measurement of crystallization rate] was used. Specifically, polypropylene was heated at 10 ° C./min from 50 ° C. to 230 ° C., and endothermic and exothermic peaks were observed. By observing the obtained endothermic exothermic peak, it was confirmed that the exothermic peak was 1.8 J / g on the low temperature side of the maximum endothermic peak.

The polypropylene sheet (base material layer) was printed to provide a printing layer. The outline of printing is as follows.
-Printing method: Screen printing method-Printing layer: 6 layers (6 color printing)
-Ink: General-purpose ink (non-polypropylene ink: manufactured by Teikoku Inks Manufacturing Co., Ltd.)
Further, a binder layer was provided on the printing layer using a two-component curable polypropylene binder (manufactured by Teikoku Inks Manufacturing Co., Ltd.) to obtain a decorative sheet.

As shown in FIG. 3, the obtained decorative sheet was indirectly heated by using the first heating means and the second heating means (both are infrared heaters). The heating conditions were set so that the temperatures of both surfaces of the decorative sheet were 160 ° C. The binder layer is not shown in FIG.
Next, the decorative sheet after heating was molded by the vacuum compressed air molding method to manufacture a shaped decorative sheet. The pressure of the vacuum compressed air molding method was 0.3 MPa.

[Measurement of crystallinity]
Since the density calculation is affected when the crystallinity of the base material layer of the shaping decorative sheet is measured, a base material layer without a printing layer and a binder layer was used for the evaluation of the crystallinity. The crystallinity of the base material layer is the same when the heat treatment is performed under the same conditions when the print layer and the binder layer are included and when the binder layer is not included.
Specifically, it is as follows.
The polypropylene sheet (base material layer) is subjected to the same heat treatment and molding as above without providing the printing layer and the binder layer, and crystallinity of the surface on the first heating means side and the surface on the second heating means side. The degree was measured respectively. The surface on the first heating means side corresponds to the surface on the printing layer side of the base material layer in the decorative sheet, and the surface on the second heating means side corresponds to the surface on the decorative sheet opposite to the printing layer of the base material layer. Corresponds to.
The surface of the polypropylene sheet (base material layer) that has been heat-treated and molded on the side of the first heating means and the surface on the side of the second heating means are each cut by 25 μm by the SAICAS (Dipla Wintes) method. The density of the cutting piece was measured by the gradient tube method (manufactured by Shibayama Kagaku Kikai Seisakusho: A type), and the crystallinity was calculated from the density of the cutting piece. The results are shown in Table 1.

[Measurement of haze value]
The haze value of the polypropylene sheet (base material layer) obtained in the same manner as in [Measurement of crystallinity] was measured. The results are shown in Table 1. All haze values were measured with a haze meter (NDH2000) manufactured by Nippon Denshoku Industries Co., Ltd.

Example 2
At the time of manufacturing the polypropylene sheet used for the base material layer, 1.5% by mass of the sorbitol-based nucleating agent "Rikemaster FC-1" (manufactured by RIKEN Vitamin Co., Ltd.) was added as a nucleating agent, and the fourth cooling of the film forming apparatus was performed. The surface cooling temperature of the roll and the endless belt was set to 120 ° C. Further, a polypropylene sheet was produced in the same manner as in Example 1 except that the take-up speed of the polypropylene sheet was set to 10 m / min.
The crystallization rate of the obtained polypropylene sheet was 3.7 min ^-1 , it had α crystals without smetica crystals, and it was 1.0 J / g or more on the low temperature side of the maximum endothermic peak by differential scanning calorimetry. It was confirmed that there was no exothermic peak. The isotactic pendat fraction was 98%.

In addition, a shaped decorative sheet was produced and evaluated in the same manner as in Example 1 using the above polypropylene sheet. The results are shown in Table 1.

Comparative Example 1
A shaped decorative sheet was produced and evaluated in the same manner as in Example 1 except that the first heating means was not used. The results are shown in Table 1.

Example 3
[Manufacturing of molded products]
The shaped decorative sheet obtained in Example 1 is mounted in a mold (flat mold: width 65 mm × length 150 mm × thickness 2 mm (one side gate: center of long side)), mold-fastened, and injected. Molding resin "Prime Polypro J705UG" (manufactured by Prime Polymer: Meltflow Index 9.0g / 10min, block polypropylene) is supplied into the mold by the molding machine "IS80EPN" (manufactured by Toshiba Machine Co., Ltd.) for shaping and decoration. A molded product was manufactured by integrating the sheet and the molding resin. The mold temperature was 45 ° C., the molding resin temperature was 240 ° C., and the injection speed of the molding resin was 18 mm / sec.

[Evaluation of ink flow]
The surface of the obtained molded product on the print layer side was visually observed near the mold gate and the cross-section was enlarged, and the ink flow phenomenon was evaluated based on the following criteria. The cross-section magnified observation was carried out with a microscope (VHX-600 (manufactured by KEYENCE), magnification 100 times) after the cross-section was adjusted with HM340E (manufactured by Microhm). The results are shown in Table 2.
〇: There was no change in the design of the print layer.
Δ: The design of the print layer was deteriorated.
X: Part or all of the print layer was lost.

Example 4
A molded product was prepared and evaluated in the same manner as in Example 3 except that the decorative sheet obtained in Example 2 was used instead of the decorative sheet obtained in Example 1. The results are shown in Table 2.

Comparative Example 2
A molded product was prepared and evaluated in the same manner as in Example 3 except that the decorative sheet obtained in Comparative Example 1 was used instead of the decorative sheet obtained in Example 1. The results are shown in Table 2.

Example 5
A molded product was produced and evaluated in the same manner as in Example 3 except that the mold temperature and the injection speed of the molding resin were changed as shown in Table 3. The results are shown in Table 3.

Example 6
A molded product was prepared and evaluated in the same manner as in Example 5 except that the decorative sheet obtained in Example 2 was used instead of the decorative sheet obtained in Example 1. The results are shown in Table 3.

Comparative Example 3
A molded product was prepared and evaluated in the same manner as in Example 5 except that the decorative sheet obtained in Comparative Example 1 was used instead of the decorative sheet obtained in Example 1. The results are shown in Table 3.

1 Decorative sheet 10 Base material layer 20 Printing layer 51 Polypropylene sheet (base material layer)
52 T-die 53 1st cooling roll 54 2nd cooling roll 55 3rd cooling roll 56 4th cooling roll 57 Metal endless belt 62 Elastic agent 100,310 1st heating means 110, 312 2nd heating means 201 Molding Decorative sheet 210, 320 First mold 220, 330 First mold 222,332 Molding resin 230, 340 Mold 320 First mold 330 Second mold

Claims (22)

A step of heating a decorative sheet including a base material layer and a printing layer, a step of heating the decorative sheet by a heating means installed so as to face the surface of the decorative sheet on the print layer side, and a step of heating the decorative sheet. A method for manufacturing a shaped decorative sheet, which comprises a step of shaping the decorative sheet after heating .
The substrate layer contains polypropylene
The crystallinity of the surface of the base material layer on the printing layer side of the shaping decorative sheet is 55% or more.
Manufacturing method of shaping decorative sheet . The method for producing a shaped decorative sheet according to claim 1, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the base material layer on the print layer side of the decorative sheet is 130 ° C. to 170 ° C. .. Claim 1 or 2 in which in the step of heating the decorative sheet, in addition to the heating means, the decorative sheet is heated by the heating means installed so as to face the surface of the decorative sheet on the base material layer side. The method for manufacturing a shaping decorative sheet described in 1. The shaped decorative sheet according to claim 3, wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the decorative sheet opposite to the printing layer of the base material layer is 130 ° C. to 170 ° C. Production method. The method for producing a shaped decorative sheet according to any one of claims 1 to 4, wherein the shaping is performed by one or more methods selected from vacuum forming, compressed air forming, vacuum forming, press molding and plug assist molding. .. The method for producing a shaped decorative sheet according to any one of claims 1 to 5 , wherein the crystallization rate of polypropylene of the base material layer at 130 ° C. before heating is 2.5 min ^-1 or less. The method for producing an excipient decorative sheet according to any one of claims 1 to 6, wherein the polypropylene isotactic pentat fraction of the base material layer before heating is 85 mol% to 99 mol%. The method for producing an excipient decorative sheet according to any one of claims 1 to 7, wherein the polypropylene of the base material layer before heating contains smetica crystals. The addition according to any one of claims 1 to 8, wherein the polypropylene of the base material layer before heating has an exothermic peak of 1 J / g or more on the low temperature side of the maximum endothermic peak in the curve obtained by differential scanning calorimetry. How to manufacture a shape decorative sheet. A shaping decorative sheet containing a base material layer and a printing layer.
Crystallinity of the surface of the print layer side of the substrate layer Ri der least 55%,
A shaping decorative sheet in which the base material layer contains polypropylene . Vehicle of claim 10 before and crystallinity of the surface of the print layer side of Kimoto material layer, the difference in the crystallinity of the surface opposite to the printed layer of the base layer is within 10% Shape decoration sheet. The shaping decorative sheet according to claim 10 or 11 , wherein the haze value of the base material layer is 15% or less. The excipient decorative sheet according to any one of claims 10 to 12, which does not contain a nucleating agent. The shaping decorative sheet according to any one of claims 10 to 13, wherein the crystallization rate of polypropylene in the base material layer at 130 ° C. is 2.5 min- ¹ or less. A step of manufacturing a shaped decorative sheet by the method for manufacturing a shaped decorative sheet according to any one of claims 1 to 9 .
The step of mounting the shaping decorative sheet in the first mold,
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. A method for manufacturing a molded product, which comprises a step of integrating the shaped decorative sheet and the molding resin. The step of mounting the shaping decorative sheet according to any one of claims 10 to 14 into the first mold.
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. A method for manufacturing a molded product, which comprises a step of integrating the shaped decorative sheet and the molding resin. A step of heating a decorative sheet including a base material layer and a printing layer, wherein the decorative sheet is heated by a heating means installed so as to face the surface of the decorative sheet on the printing layer side.
The step of cooling the heated decorative sheet to room temperature and arranging it on the first mold.
The step of molding the first mold and the second mold facing the first mold, and the molding resin is supplied from the injection port provided in the second mold. The process of integrating the decorative sheet and the molding resin,
It is a manufacturing method of a molded product containing
The substrate layer contains polypropylene
A method for producing a molded product in which the crystallinity of the surface of the base material layer on the printing layer side after cooling is 55% or more . The method for producing a molded product according to claim 17 , wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the base material layer on the print layer side of the decorative sheet is 130 ° C to 170 ° C. Claim 17 or 18 in the step of heating the decorative sheet, in addition to the heating means, the decorative sheet is heated by the heating means installed so as to face the surface of the decorative sheet on the base material layer side. The method for producing a molded product according to. The method for producing a molded product according to claim 19 , wherein the decorative sheet is heated under the condition that the surface temperature of the surface of the decorative sheet opposite to the printed layer of the base material layer is 130 ° C to 170 ° C. Claim that the difference between the crystallinity of the surface of the base material layer on the print layer side and the crystallinity of the surface of the base material layer opposite to the print layer before cooling is within 10%. The method for producing a molded product according to any one of 17 to 20. A molded product produced by using the shaping decorative sheet according to any one of claims 10 to 14 .

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