JPH09193239A - Preheating method in sheet molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the strain in the patterns of molded object by locally preheating the molding corresponding part of a molding sheet having a preparatory pattern layer outside and/or inside the side surface thereof in a molded object having an opening part and molding the preheated part to form a pattern layer. SOLUTION: A molding sheet 50 is composed of a single layer or multilayered structure containing at least a thermoplastic resin layer and a molded object 20 has an opening part 35 and a preparatory pattern layer 60 specified so as to estimate a stretched state is provided to at least one of the outside 31 and/or inside 31 of a molded side surface. A heat barrier plate having a heating hole for locally preheating the molding corresponding part 10 of the molding sheet 50 is provided. By this constitution, the molding corresponding part of the molding sheet 50 is uniformly preheated to obtain the molded object 20 having a desired pattern layer 61 formed thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a molded article having a pattern layer, and more specifically, it is formed by a method such as drawing or drawing from a sheet such as pressure forming or vacuum forming. Nevertheless, it belongs to a manufacturing method in which a desired pattern layer having no distortion can be accurately provided on the side surface portion.

[0002]

Conventionally, when a molded body is manufactured from a synthetic resin sheet (hereinafter referred to as sheet molding in this specification), the periphery of the molded product is fixed,
If necessary, plug assist is used to perform stretching or drawing by pressure forming or vacuum forming. However, when a pattern layer is provided on the surface of the molded product, curved surface printing is performed on the molded product. When a sheet having good productivity is provided with a preliminary pattern layer and subjected to molding, there is a problem that the desired pattern layer cannot be obtained accurately because the sheet in the molding part is not uniformly deformed.

The present invention provides a molded product having an accurate pattern layer without distortion on the side surface of a molded product produced by the sheet molding method, and can be applied to the sheet molding method to display parts, molded products. It is an object of the present invention to provide a molded product having a pattern layer by mass production without being limited to the shape or size of the above.

In order to achieve the above-mentioned object, the present invention is a molded product which is molded using a plug and / or a pressure fluid in a state where the periphery of the molding sheet is fixed, and the molding sheet is at least The molded body has a single-layer or multi-layer structure including a thermoplastic resin layer, the molded body has an opening, and the molded body is expected to have a stretched state on at least one of the outside of the molding side surface and / or the inside of the molding side surface. In the forming sheet having the preliminary pattern layer provided as described above, a preheating method in sheet molding is performed in which a desired pattern layer is formed by locally preheating and molding a portion corresponding to molding. Then, on the surface of the preliminary pattern layer, a thermoplastic resin layer, and / or
Alternatively, a preheating method in sheet molding in which a molded body is obtained by using a molding sheet provided with a protective layer of a reactive resin layer. Further, it is a preheating method in the sheet forming in which a portion corresponding to the forming can be uniformly heated by providing a heat shield plate having a heating hole for heating the portion corresponding to the forming of the forming sheet.

[0005]

2. Description of the Related Art In the production of a synthetic resin molded product belonging to the sheet molding method, a sheet-shaped molded substrate is softened by heating or fixed around its periphery without being heated, and if necessary, plug assist is performed. The sheet was formed by vacuum or pressure forming. Such sheet molding has been widely used as a method suitable for mass production because not only the cost of equipment such as a molding machine is low, but also the molding speed is high as compared with other methods such as injection molding.

Sheet forming is usually known as a curved surface printing method when a pattern layer such as characters, figures or images is desired to be formed on the surface of a molded body, and the molded sheet is molded into a desired shape. It was provided by dry offset printing, gravure offset printing, pad printing, silk screen printing, etc. In addition, an image is printed on a roll or a sheet, and a pattern layer is displayed by a label or transfer printing. However, except for special cases, these methods can be applied to the surface to be printed of the molded product on the curved surface that is the secondary surface, but it is especially suitable for those with a three-dimensional shape with uneven patterns and those with a small shape. I needed a jig and a dedicated machine.

If it is difficult to print the molded product,
A method of performing molding and printing at the same time, for example, inserting a label into a mold to perform injection molding (in-mold label method), inserting a transfer film into the mold and performing injection molding, and applying heat and pressure of resin. There is a method of transferring the pattern layer or a method of injection molding using a plurality of resins having different types or colors. However, these methods are injection molding methods, and there are problems that not only the mold cost increases but also the molding speed is slow and the productivity is low. In particular, in the method of inserting a label or a transfer film into a mold, there is a problem that an automatic inserting machine is required depending on the type and size, and equipment cost is required.

The above-mentioned in-mold label method is also applied to sheet molding, but not only the cost of installing an automatic label inserting machine, but also wrinkles and label positions when the label is inserted. There was a problem that production loss was large due to deviation.

On the other hand, in the field of metal plastic working, it is also practiced to form a preliminary pattern layer on the surface of a metal plate and then deep draw the metal plate. In this method, a distorted preliminary pattern layer determined in consideration of the stretching ratio of the metal is printed on the surface of the metal plate, and the distorted preliminary pattern layer follows the stretching of the metal plate to be formed. When it is deformed and the molding is completed, a desired pattern layer can be obtained. Further, according to this method, the surface layer of the molded product having a large number of irregularities and a pattern layer can be formed even if the molded product is small.

However, when molding a thermoplastic resin layer sheet provided with a preliminary pattern layer, unlike the case of a metal plate, it may be caused by unevenness of the thickness of the sheet itself. It is difficult, and unevenness in meat pressure and stretching is likely to occur. Therefore, simply printing the preliminary pattern layer in consideration of the stretching ratio of the molding sheet does not transform the pattern layer into the pattern layer as expected, and the distortion-free pattern layer cannot be completed as a molded body. However, exceptionally, since the molding sheet in the portion corresponding to the bottom surface of the molded body is unlikely to cause stretching unevenness, it is relatively effective to provide the preliminary pattern layer in the molding sheet only in this portion. is there.

There is not yet a printing method which is not limited to the display portion, the shape or size of the molded body by the sheet molding, and is suitable for mass production, particularly a molding method in which a distortion-free pattern layer is provided on the side surface of the molding. That is the reality.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A molded body 20 provided with a pattern layer of the present invention.
In order to form the molded body 20 having the pattern layer 61 shown in FIG. 1, the laminated sheet 50 provided with the reference lines 3 and the reference points 4 as shown in FIG. With the periphery thereof fixed by the fixing jig 90, the plug 93 and / or the pressure fluid is used to form the molded body 20, and the reference point 4 of the molded body is used.
Is measured to predict the stretched state of the molding sheet to define the preliminary pattern layer 60. The molding sheet 50 has a single-layer or multi-layer structure including at least a thermoplastic resin layer, the molding has an opening 35, and the molding side surface outside 31a and / or the molding side surface inside 31b of FIG. As shown in FIG. 21, in order to locally preheat the portion corresponding to the molding of the molding sheet 50 in which the preliminary pattern layer 60 that predicts and defines the stretched state is provided on at least one side, FIG. By providing a heat shield plate 80 having a heating hole 81 shown in FIG. 3, uniform preheating of the molding-equivalent portion of the molding sheet 50 is performed, heating unevenness is prevented, and the desired pattern layer is formed by molding at a uniform draw ratio. This is a preheating method in the sheet forming to obtain the formed body 20 forming 61.

The molded article of the present invention is one in which a pattern layer having no distortion or misalignment when the molding is completed is formed on the surface of a molding sheet having a thermoplastic resin layer as a main constituent element. That is, a molded product having a normal pattern layer is manufactured by molding a sheet provided with a preliminary pattern layer that is initially distorted, but not only the stretching ratio of the molding sheet but also stretching unevenness is considered. The stretched state is predicted, and based on the result, the deformation and the display position when the preliminary pattern layer is formed are determined. The preliminary pattern layer is deformed as predicted following the stretching of the molding sheet.

According to the present invention, if the stretching state of the molding sheet is first predicted and the degree of distortion of the preliminary pattern layer and the display position are set, regardless of whether or not stretching unevenness occurs,
The preliminary pattern layer provided on the molding sheet can be provided with a normal pattern layer on the surface of the molded product. Therefore, it is possible to efficiently mass-produce a molded product having an accurate pattern layer without distortion or displacement by the sheet molding method. The sheet forming machine does not require any special equipment such as an automatic label automatic label inserting machine.

The molded article having the pattern layer of the present invention obtained by the above method is irrespective of what is produced by sheet molding, a place where stretching unevenness is likely to occur, for example, a molding side surface portion or a complicated surface shape. This is a method that has never existed before and can display the predicted pattern layer at a place or the like.

Hereinafter, further details will be described based on embodiments. FIG. 1 is a perspective view of a molded body 20 having a pattern layer 61 of the molded body of the present invention, and FIG. 2 is a diagram schematically showing a cross section of the same molded body. FIG. 4A is a plan view of the molding sheet 50 in which the preliminary pattern layer 60 is provided on the molding sheet 1 before molding the molded body 20, and FIG. It is a perspective view of the obtained molded body 20.
In addition, FIGS. 5A, 5B, 5C, 5D, and 5E
Are formed bodies 51, 5 of other shapes having the pattern layer of the present invention.
It is a perspective view which shows 2, 53, 54, and 55.

The molded body 20 having the pattern layer 61 of the present invention is
As shown in FIG. 1 and FIG. 2, the opening 35 whose inside is a cavity
And the molding bottom surface 33, and the pattern layer 61 is provided on at least one of the molding side surface portion 31 including the molding side surface outside 31a and the molding side surface inside 31b. The illustrated pattern layer is a bar code and is provided only on the outer side 31a of the molding side. The molded body 20 has a thickness of 500 μm, for example.
A-PET (amorphous polyethylene terephthalate sheet) disc-shaped single-layer substrate 1 is provided with concentric circular and radial reference lines 3 at the center 2 of the molding sheet shown in FIG. 4 (A). A molding sheet 50 provided with a preliminary pattern layer defining the reference point 4 which is the intersection is prepared. Then, with a sheet forming machine, as shown in FIGS.
Then, the molding sheet 50 provided with the preliminary pattern layer is fixed, heated to a temperature at which the molding sheet 50 can be molded, and the plug-driving mold is moved to move the plug 50 to the center line of the molding sheet 50 and the upper and lower sides. Center line 94 of molds 91, 92 and plug 93
To match. Further, the plug 93 and the compressed air (96) were activated, and the vacuum (95) was utilized to complete the plug assist molding. The obtained molded body 20 has a flat-bottomed cylindrical shape having a collar-shaped molded portion periphery 36 on the opening 35 side shown in FIG. 4 (B).

The reference point 4 of each part of the obtained molded body 20 is measured to predict the stretched state of the molding sheet, and conversely, the preliminary pattern layer to be stretched and deformed into a desired pattern layer is defined. is there. Hereinafter, the preliminary pattern layer in the present specification is formed by using the one obtained by the above method.

The preheating method for the forming sheet, which is carried out by sheet forming, includes a contact heating method in which the forming sheet is sandwiched between upper and lower heaters and the heater is directly contacted with the portion corresponding to the forming to heat and soften it, and a heater. There is a non-contact heating method in which a space is provided between the sheet for molding and heating and softening by radiant heat. The contact heating method has a problem that, when heating the forming sheet, there is a problem that the feed temporarily stays and it is difficult to take out a large number of formed bodies, but only a portion corresponding to the forming of the forming sheet is formed. There is a feature that heating is easy. On the other hand, the non-contact heating method is a continuous sheet,
A wide sheet can be used, and the forming sheet can be sent without staying depending on the heating device and the forming device.

The present invention relates to a heat shield plate for effectively heating a heating heater to a portion corresponding to molding. The heat source of the preheating heater is not particularly limited as long as it can control heating to a temperature at which the molding sheet can be molded, and the output wavelength band is either far infrared or near infrared. It may be one with a ceramic heater, rod heater, quartz heater, halogen lamp heater, etc. These heaters are used on one side and / or both sides, and a required number of heaters of an appropriate size can be provided depending on the length and width of the heating device. The preheating temperature and time are appropriately determined depending on the type and thickness of the forming sheet, the shape of the formed body, and the like.

The material of the heat shield plate is not particularly limited as long as it is resistant to deformation and deterioration when exposed to the temperature in the heating device for a long time, and iron, aluminum, stainless steel,
In addition to brass or heat resistant alloys made of carbon steel and nickel, chromium, molybdenum, etc., heat resistant polyimide laminated with metal foil using a high heat resistant adhesive,
It is sometimes used because of its light weight and ease of processing. Also,
In order to prevent overheating of the heat shield plate itself, it is desirable to provide the heat shield plate with a cooling mechanism. As a cooling mechanism,
Cooling water may be caused to flow in the heat shield plate, or the heat shield plate may be once taken out of the heating device and cooled by outside air or a cooling medium.

The shape of the heating hole of the heat shield plate can be appropriately determined so that it can be formed and installed so that only the portion corresponding to the forming of the forming sheet is heated uniformly.

FIGS. 6A, 6B, 6C and 6D show structural examples of the heating device and the heat shield plate. In the conventional heating device shown in FIG. 6A, the molding sheet 1 is heated during heating.
However, in order to prevent overheating in the heating device after completion of heating, it is necessary to provide a mechanism for quickly taking out.
The heat shield plate 80 shown in FIG. 6B is one in which the heating holes 81 are provided in the heat shield plate 80 only in the portion corresponding to molding. It is preferable to flow the cooling water 71 around the heating holes. FIG. 6 (C)
The heating device shown in FIG. 2 has a rotary belt type heat shield plate 80,
The amount of heat supplied can be adjusted by changing the feeding speed according to the line speed of the molding sheet 1. Further, the heat shield plate 80 can be cooled to a proper temperature by using air or a refrigerant outside the heating unit. The heat shield plate 80 shown in FIG. 6 (D) is of a belt type that rotates in accordance with the line speed of the forming sheet 1, and the heat shield plate 8 corresponding to the forming portion.
0 is provided with a heat insulating plate 86 and a heating hole 81 to continuously heat the molding corresponding portion 10. FIG. 6 (A),
In both heating devices of (B), the installation location of the heater 7 is
It may be provided on either or both of the upper and lower sides of the heat shield plate 80. Further, there is no limitation in providing a temperature gradient in the heating device.

The shape of the molded product having an opening is shown in FIG.
5 is not limited to the flat bottom cylindrical shape shown in FIG.
As shown in (A), (B), (C), (D), or (E), a round-bottomed cylindrical molded body 51, a hemispherical molded body 52, a shallow convex molded body 53, and a rectangular parallelepiped molded body 54. Alternatively, all shapes that can be formed by sheet molding such as the polygonal columnar molded body 55 can be manufactured. When the molded body has a round bottom shape, a hemispherical shape, a shallow convex surface, or the like, the boundary between the molding bottom surface and the molding side surface is not clear, but the molding side surface portion of the molding body in the present invention is a molded body. In the case of forming the body part of, and printing the preliminary pattern layer only by calculating the stretching ratio of the forming sheet, the preliminary pattern layer does not deform, and if the stretching unevenness is not considered, It means a region where a pattern layer without distortion or misalignment cannot be completed, and includes those that are not apparent in appearance. The periphery 36 of the molded portion has an appropriate size depending on the intended use of the molded body, but it is necessary to secure a space that can be fixed during molding.

The pattern layer 61 having no distortion or displacement is shown in FIG.
1 shows a forming sheet 50 in which a preprinted distorted preliminary pattern layer 60 is provided on a forming sheet 1 having a disc-shaped forming portion 10 shown in FIG. The preliminary pattern layer is completed as a pattern layer as a result of being deformed following the stretching of the sheet at the time of forming the sheet. The degree of distortion of the preliminary picture layer and the position of the display are determined in consideration of not only the stretching ratio of the molding sheet but also the stretching unevenness.

The molded product of the present invention may have either a single-layer structure or a laminated structure, but in the case of a multilayer structure, it is necessary to include a thermoplastic resin layer as a main layer. For example, the molded body 20 shown in FIG. 2 has an outer surface thermoplastic resin layer 21.
Is provided with a pattern layer 61, and the other inner surface resin layers 22 and 23 and the innermost surface layer 25 are laminated by layers selected in consideration of the use of the molded body. The laminated sheet of the molded body may have two or more thermoplastic resin layers, for example, the inner surface layers 22 and 23 may be thermoplastic resin layers, and the innermost surface layer 25 is In addition to the thermoplastic resin layer, a flexible reactive resin layer or a metal foil layer may be used. The pattern layer 61 can be protected by providing a pattern protection layer 62 made of a thermoplastic resin layer or a flexible reaction type resin layer.

The molding sheet may be a single layer of a thermoplastic resin layer, but when it has a laminated structure, it contains at least a main layer of a thermoplastic resin layer, and the layer provided with the preliminary pattern layer is thermoplastic. It must be formed of a resin layer.

The thickness of the molding sheet is 50 to 2000 μm.
It is. Then, the sheet can be manufactured by forming a film using a known T-die or circular die, or combining an existing sheet or film with dry lamination provided with an adhesive layer or melt extrusion coating as necessary. . Thermoplastic resin layer, polyolefin resin, polystyrene resin, polyester resin, vinyl chloride resin, polyamide resin, polyimide resin,
Examples include polyurethane resins, acrylic resins, ABS, acrylonitrile resins, and cellulose derivatives. In addition to these, as a functional resin, ethylene
Vinyl alcohol copolymer, hygroscopic resin, adhesive resin,
Elastomer, release resin (fluororesin, silicone)
and so on.

The thermoplastic resin layer may be blended with other components with an upper limit of 40% by weight to add a special function. For example, calcium carbonate, magnesium carbonate, aluminum hydroxide, magnesium hydroxide, zinc oxide, magnesium oxide, aluminum silicate, calcium silicate, zeolite and the like can be used as a bulking material, reducing calories burned, and flame retardant material. it can. In addition, a pigment, metal powder, carbon black, or the like that gives a light-shielding property, an ultraviolet blocking property, a color, or the like can be added.

An antistatic agent is preferably added to the thermoplastic resin layer in order to prevent printing stains. Examples of the antistatic agent include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and a tetrafunctional silicon partial hydrolyzate. In addition, metal powder, metal oxide powder, metal sulfide, etc., which have been subjected to conductive treatment to prevent dust adhesion and sheet electrification, conductive carbon, bisammonium organic sulfur semiconductor and so on. The antistatic agent may be added to an adhesive layer, a protective layer, or the like, may be added to a material between layers of the molding sheet, or may be applied to the surface.

Adhesives or anchor coating agents used when laminating the layers of the molding sheet include polyolefin-based, polyethyleneimine-based, polybutadiene-based, organic titanium compounds, polyester-based, polyurethane-based and isocyanate-based adhesives. . Examples of the adhesive resin include a thermoplastic resin layer having at least one carbonyl group such as a carboxylic acid, a carboxylate, a carboxylic anhydride, a carboxylic amide, and a carboxylic ester in a main chain or a side chain. For example, ethylene-acrylic acid copolymer, ionomer, maleic anhydride-grafted polyethylene, maleic anhydride-grafted polypropylene, acrylic acid-grafted polyolefin, ethylene-vinyl acetate copolymer,
Examples include polyester-based resins and polyamide-based resins. Then, these, the adhesive, anchor coating agent, a multilayer sheet laminated via an adhesive resin, a known bonding method,
It can be formed by coextrusion.

Low-density polyethylene, low-medium density linear polyethylene, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / acrylic acid ester copolymer, ionomer, polypropylene are provided between the layers of the molding sheet. And the like can be used as the rigidity adjusting layer of the molding sheet. In this case, the adhesion can be strengthened by using the above-mentioned adhesive or anchor coating agent. In addition, the thickness of the adhesive layer is preferably 1 μm to 10 μm, and the thickness of the adhesive resin layer and the rigidity adjusting layer is preferably 5 to 200 μm.

It is preferable to provide a protective layer on the preliminary pattern layer in order to prevent the pattern layer from falling off or being contaminated due to friction with a mold during sheet molding or physical or chemical damage when the molded product is distributed. . The protective layer is formed by laminating the above thermoplastic resin layer film, polyester resin, polyolefin resin, acrylic resin, urethane resin, vinyl chloride / vinyl acetate copolymer, polyamide resin, cellulose derivative. A plasticizer is added to a varnish or a water-soluble dispersion obtained by dissolving one or two or more mixed resins in a solvent.
A dispersion of a lubricant, an antistatic agent and other auxiliaries can be applied and used. Further, an acrylic ionizing radiation curable resin or a highly flexible reaction curable resin such as vinylated alkyd can be applied and formed as a protective layer for the pattern layer. The thickness of the protective layer is 5 to 8 for the film.
0 μm, and 1 to 50 μm when applied.

10 to 21 show examples of the molding sheet having the multilayer structure of the present invention. (1) A molding sheet 50 shown in FIG. 10 having a layer structure of a preliminary pattern layer 60 / an outer surface thermoplastic resin layer 21, an adhesive layer 41, and an inner surface thermoplastic resin layer 22. (2) As shown in FIG. 11, preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / adhesive layer 41 / inner surface thermoplastic resin layer 22
/ A forming sheet 50 having a layer structure in which a pattern layer is provided on both surfaces of the preliminary pattern layer 60. (3) Preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / adhesive resin layer 42 / oxygen-blocking thermoplastic resin layer 1 shown in FIG.
1 / Adhesive resin layer 42 / Inner thermoplastic resin layer 22 forming sheet 50 (4) Preliminary pattern layer 60 / outer thermoplastic resin layer 21 / oxygen absorbing thermoplastic resin layer 12 shown in FIG. Molding sheet 5 having a layer structure of / oxygen blocking thermoplastic resin layer 11 / oxygen absorbing thermoplastic resin layer 12 / inner surface thermoplastic resin layer 22
0. (5) Preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / water-absorbing thermoplastic resin layer 13 / oxygen-blocking thermoplastic resin layer 11 / water-absorbing thermoplastic resin layer 13 / inner surface thermoplastic resin shown in FIG. Molding sheet 5 having a layer structure of the resin layer 22
0. (6) Preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / adhesive resin layer 42 / metal foil 17 / adhesive resin layer 42 shown in FIG.
/ A molding sheet 50 having a layer structure of the inner surface thermoplastic resin layer 22. (7) A molding sheet 50 shown in FIG. 16 having a layered structure of preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / paper 18 (or nonwoven fabric 19) / inner surface thermoplastic resin layer 22. (8) A molding sheet 50 shown in FIG. 17, which has a layered structure of preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / adhesive layer 41 / non-adhesive resin layer 14. (9) A molding sheet 50 shown in FIG. 18, which is composed of a preliminary pattern layer 60 / a layer structure of an antibacterial, antifungal material or a biodegradable inner thermoplastic resin layer 15. (10) A molding sheet 50 shown in FIG. 19 having a layer structure of a preliminary pattern layer 60 / an outer surface thermoplastic resin layer 21, an adhesive layer 41, and a foamed resin layer 16. (11) Molding sheet 5 shown in FIG. 20 having a layer structure of protective layer 66 / preliminary pattern layer 60 / inner surface thermoplastic resin layer 22.
0. (12) As shown in FIG. 21, protective layer 66 / adhesive layer 41 / preliminary pattern layer 60 / outer surface thermoplastic resin layer 21 / adhesive layer 41 /
A molding sheet 50 having a layer structure of an oxygen-blocking thermoplastic resin layer 11 / adhesive layer 41 / inner surface thermoplastic resin layer 22.

[0035]

EXAMPLE As shown in FIG. 7, as a molding sheet 1, a 500 μm thick DENKA A-PET “trade name of Denki Kagaku Kogyo Co., Ltd.” was used, and a urethane resin / vinyl chloride / vinyl acetate copolymer ( (Weight ratio: 35/65), screen printing using an ink prepared by adjusting 50% by weight of a binder made of a lubricant and 50% by weight of carbon black with a solvent,
A forming sheet 50 in which a preliminary pattern layer 60 in which the draw ratio is predicted and converted in advance is provided on the forming side surface portion 31 of the forming equivalent portion 10
It was created. Then, as shown in FIG. 8 (A), a sheet forming machine having a stainless steel heat shield plate 80 having the same heat shield plate heating hole 81 as that of the molding corresponding portion 10 and a ceramic heater is used, as shown in FIGS. As shown in D), the fixing jig 90
Then, the molding sheet 50 provided with the preliminary pattern layer is fixed, heated to a temperature at which the molding sheet 50 can be molded, and a center line of the molding sheet 50 and upper and lower molds 91 are formed by a plug-driving mold. , 92 and the center line 94 of the plug 93 are aligned. Then, the plug 93, the compressed air (96), and the vacuum (9
5) was used to perform plug assist molding. As shown in FIG. 9 (A), the obtained molded body 20 has a periphery 36 of a brim-shaped molded portion on the side of the opening 35, and the pattern layer 61 has a predetermined dimension in both vertical and horizontal dimensions t and y after molding. It was a good product with no distortion.

[0036]

[Comparative Example] Using the forming sheet 50 having the preliminary pattern layer 60 prepared in Example 1 in which the stretch ratio was predicted and converted in advance and provided in the forming-corresponding portion 10, the forming-corresponding portion was formed as shown in FIG. 8B. The heat shield plate 80 of Comparative Example 1 having the heating holes 82 smaller than 10, the heat shield plate 80 of Comparative Example 2 having the heating holes 83 larger than the molding corresponding portion 10 as shown in FIG. 8C, and FIG. As shown in D), molding was carried out in the same manner as in Example 1 using the heat shield plate 80 of Comparative Example 3 having the same size as the molding corresponding portion 10 but having the heating holes 84 displaced in position. The molded body obtained by using the heat shield plate of Comparative Example 1 is
As shown in FIG. 9 (B), heat is not sufficiently transmitted to the molded part shielded by the heat shield plate, and the part is insufficiently stretched. It had a pattern layer 61 in which the desired stretching was insufficient. Further, the periphery 36 of the molding portion could not be sufficiently heated and the moldability was poor. The molded body obtained using the heat shield plate of Comparative Example 2 was
As shown in FIG. 9C, the pattern layer 61 was excessively stretched to cause distortion, and the periphery 36 of the molded portion was overheated, so that the pattern layer 61 was curved and a satisfactory molded body could not be obtained.
Also in the molding using the heat shield plate of Comparative Example 3, the pattern layer 61 is stretched non-uniformly to cause distortion, and the shape of the periphery 36 of the molded body is also non-uniform as shown in FIG. 9 (D). Body deformation and curvature were also large and moldability was poor.

Table 1 shows the dimension lateral y after molding, the dimension vertical t after molding, and the moldability of the pattern layers obtained in Examples and Comparative Examples.
Shown in However, the target finish value of the pattern layer is y: 20 m
m, t: 20 mm. In addition, the evaluation criteria for moldability are
Do it visually. ◯: The pattern layer can be normally formed as expected. X: Both the pattern layer and the molded product are unsatisfactory. -: The pattern layer is distorted and the t and y dimensions cannot be measured. (Below margin)

[0038]

[Table 1]

[0039]

As described above in detail, the molded product formed into a sheet by the preheating method of the present invention can uniformly heat only the molding-corresponding portion of the molding sheet, and the pattern of the molded product can be obtained. It has an effect of obtaining a good molded product without distortion.

[Brief description of the drawings]

FIG. 1 is a perspective view of a molded body of the present invention.

FIG. 2 is a schematic view showing an example of a cross section of a molded body.

FIG. 3 (A) is a schematic sectional view of a molding machine for explaining an outline of a sheet molding mechanism and a fixing state of a molding sheet. FIG. 3B is a schematic cross-sectional view showing a state where the molding sheet is heated and the mold is moved. (C) It is the cross-sectional schematic which shows the state which the plug and the compressed air were operated, and the sheet | seat for shaping | stretching was extended. (D) is a schematic sectional view showing a state in which molding has been completed using vacuum.

FIG. 4 (A) is a plan view for explaining a molding sheet provided with a preliminary pattern layer. FIG. 3B is a perspective view showing a molded body of the molding sheet.

FIG. 5 (A) is a perspective view of a round-bottomed cylindrical molded body. (B) It is a perspective view showing a hemispherical molded body. FIG. 3C is a perspective view of a shallow convex molded body. (D) is a perspective view showing a rectangular parallelepiped shaped body. (E) is a perspective view showing a polygonal columnar molded body.

FIG. 6 (A) is a schematic cross-sectional view showing an example of a conventional method for heating a molding sheet. (B) is a schematic plan view showing a heat shield plate provided with heating holes. (C) It is the schematic of the cross section which shows an example of the heating method by a belt type heat shield plate. (D) It is the schematic figure of the cross section which shows an example of the heating method by the belt type heat shield plate which provided the heating hole.

FIG. 7 is a plan view of a molding sheet provided with a preliminary pattern layer.

FIG. 8 (A) is a schematic plan view of a heat shield plate showing the same heating holes as those in the portion corresponding to molding. (B) is a schematic plan view of a heat shield plate showing a heating hole smaller than a portion corresponding to molding. (C) is a schematic plan view of a heat shield plate showing a heating hole larger than a portion corresponding to molding. (D) It is a schematic plan view of a heat shield plate having a heating hole at a position, which is deviated from a portion corresponding to molding.

9 (A) is a schematic cross-sectional view showing the molded body and the pattern layer of Example 1. FIG. (B) is a schematic cross-sectional view showing the molded body of Comparative Example 1 and the pattern layer. (C) is a schematic cross-sectional view showing a molded body and a pattern layer of Comparative Example 2. (D) is a schematic cross-sectional view showing a molded body and a pattern layer of Comparative Example 3.

FIG. 10 is a schematic sectional view showing an example of the multilayer molding sheet of the present invention.

FIG. 11 is a schematic sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 12 is a schematic sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 13 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 14 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 15 is a schematic sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 16 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 17 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 18 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 19 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 20 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

FIG. 21 is a schematic cross-sectional view showing another example of the multilayer molding sheet of the present invention.

[Explanation of symbols]

 1 Molding sheet 2 Center of molding sheet 3 Reference line 4 Reference point 10 Molding equivalent part 11 to 15 Functional resin layer 11 Oxygen-blocking thermoplastic resin layer 12 Oxygen-absorbing thermoplastic resin layer 13 Moisture-absorbing thermoplastic resin Layer 14 Non-adhesive resin layer 15 Antibacterial, antifungal or biodegradable thermoplastic resin layer 16 Foamed resin layer 17 Metal foil 18 Paper 19 Nonwoven fabric 20 Molded body 21 External thermoplastic resin layer 22 Internal thermoplastic resin layer 25 Innermost layer 31 Molding side surface 31a Molding side surface 31b Molding surface inside 33 Molding bottom surface 33a Molding bottom surface 33b Molding bottom inside 35 Opening 36 Surrounding the molding area 41 Adhesive layer 42 Adhesive resin layer 50 Molding sheet with a preliminary pattern layer 51 52, 53, 54, 55, molded body with pattern layer 60 Preliminary pattern layer 61 Pattern layer after molding 66 Protective layer 7 Heater 71 Cooling water 80 Heat shield plate 81, 82, 83, 84 Heating of heat shield plate Hole 86 Insulation plate 90 Fixing jig 91, 92 Mold 93 Plug 94 plug Center line of the lug t Vertical dimension of the pattern after molding y Horizontal dimension of the pattern after molding

Claims (3)

[Claims] 1. With the periphery of the molding sheet fixed,
A molded body molded using a plug and / or a pressure fluid, wherein the molding sheet further comprises a single layer or a multilayer structure containing at least a thermoplastic resin layer, and the molded body is
It has an opening, and the molded body has a molding side surface and / or
Or, in a molding sheet having a preliminary pattern layer provided by predicting the stretched state on at least one side surface of the molding side surface, a desired pattern layer is formed by locally preheating the molding-corresponding portion. A preheating method in sheet forming, which comprises: 2. A molded product is obtained from a molding sheet having a protective layer formed of a thermoplastic resin layer and / or a reactive resin layer on the surface of the preliminary pattern layer.
Preheating method in the sheet molding described. 3. The molding-corresponding portion can be uniformly heated by providing a heat shield plate having a heating hole for heating the molding-corresponding portion of the molding sheet.
Preheating method in the sheet molding described.