JPH04128036A - Laminated molded object - Google Patents

Abstract

PURPOSE:To obtain the laminated molded object excellent in durability, while the covering layer with uniform, sufficient and optional thickness may be obtained on the whole range of the laminated formed object by polymerizing, with solidification, the synthetic resin which contains a polymer and pas fluidity onto the crystalline resin or synthetic resin-base mainly by heating them in a mold. CONSTITUTION:A synthetic resin covering layer is molded by polymerizing, with solidification, under heating the synthetic resin material which contains monomer and has fluidity in a mold. Synthetic resin base is mainly made of crystalline resin or the mixture of crystalline resin with amorphous resin, whereby said resin base becomes the material excellent in chemical resistance. Further, while a decorative member or a primer is caused to intervene between the synthetic resin covering layer and the synthetic resin base, their linear expansion factors are approximated, whereby the warpage of the laminated molded object due to surrounding temperature-change or the crack and peeling of the synthetic resin covering layer are avoided.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a laminated molded product used as a decorative board in automobile instrument panels, etc., and in particular,
The present invention relates to a laminate molded product having a synthetic resin base material and a synthetic resin coating layer.

[Conventional technology]

Decorative panels with wood grain patterns are often used in automobile instrument panels. Conventionally, such decorative boards are made by gluing a veneer with a thickness of about 0.1 to 0.5 mm onto a base material such as plywood or aluminum, and then coating it with a thick coat of clear paint. Those with layers are generally known.

[Problem to be solved by the invention]

However, such decorative boards have problems such as warping due to changes in ambient temperature, cracking or peeling of the coating layer due to the difference in linear expansion coefficient between the base material and the coating layer. There is. In addition, in such decorative laminates that use a paint film for the coating layer, as the shape of the base material becomes more complex, such as a three-dimensional shape, the thickness of the paint film coating layer must be kept uniform and sufficient over the entire decorative laminate. There is also the problem that it becomes difficult to do so. Furthermore, when using a paint film for the coating layer, it is necessary to apply several layers of paint to ensure the film thickness.
Furthermore, in order to improve the adhesion between each layer and the smoothness of the coating film, it may be necessary to sand the coating before applying the next layer. Additionally, the surface of the final finishing layer may be polished. Therefore, there is a problem that the number of man-hours becomes enormous and the cost rises. The present invention was made in view of these problems, and its purpose is to make the thickness of the coating layer uniform and sufficient over the entire molded product, regardless of the shape of the base material. It is an object of the present invention to provide a high-quality laminate molded product that can be manufactured at low cost and has high durability against changes in ambient temperature.

[Means to solve the problem]

In order to achieve this objective, in the present invention, a synthetic resin coating layer is formed by heating a synthetic resin material containing a monomer and having fluidity in a mold to polymerize and solidify the coating layer. are laminated onto a synthetic resin base material mainly made of a crystalline resin or a mixture of a crystalline resin and a non-crystalline resin, with a decorative member or primer sandwiched between them, thereby constructing a laminate molded product. ing. The synthetic resin base material is said to have a linear expansion coefficient close to that of the synthetic resin coating layer.

[Effect]

In this way, by forming a synthetic resin coating layer by heating and polymerizing and solidifying a synthetic resin material containing a monomer and having fluidity in a mold, the shape of the base material can be changed to, for example, 3. Even if the dimensional shape is complex, it is possible to make the thickness of the coating layer uniform and sufficiently arbitrary over the entire laminate molded product. Therefore, it is possible to achieve a high level of uniformity and arbitrariness in appearance quality. In addition, since the desired coating layer can be formed in one culm by molding, the number of man-hours does not become large unlike coating layers by painting, and quality control becomes easier.
Costs can also be kept low. In addition, by making the synthetic resin base material mainly composed of a crystalline resin or a mixture of a crystalline resin and a non-crystalline resin, excellent chemical resistance can be obtained. It will not be attacked by monomers, etc. contained in the material and will not cause dissolution or foaming. Therefore, the surface of the base material is prevented from becoming rough, and problems such as a decrease in adhesive strength when bonding a member such as a veneer to the surface of the base material are avoided. Furthermore, by interposing a decorative member or a primer between the synthetic resin coating layer and the synthetic resin base material, and by approximating their linear expansion coefficients, warping of the laminated molded product due to ambient temperature changes, and Problems such as cracks and peeling of the resin coating layer are also avoided. In the present invention, the synthetic resin material for forming the synthetic resin coating layer is not particularly limited as long as it contains monomers and has fluidity, but is preferably JP-A-61
-127726 publication or JP-A-60-20212
A partial polymer of thermosetting resin as disclosed in Japanese Patent No. 8 is used. The partial polymer is made by partially polymerizing a synthetic resin material containing monomers, and it contains monomers that remain unreacted, and is molded by pressurizing and heating in a mold.・It is then cured to become a complete polymer. Particularly preferred synthetic resin materials include (A) 1 to 60% by weight of a crosslinkable monomer, and (B) 99 to 40% by weight of an unsaturated monomer, which is mainly composed of alkyl methacrylate and may contain a dissolved polymer thereof. Partially crosslinked gel-like polymer in which the polymer content of the mixture with % by weight is increased by 4.62% by weight over the polymer content in the mixture within a range where the total polymer content does not exceed 80% by weight. can be mentioned. Here, the amount of crosslinkable monomer (A) used is 1 to 60
% by weight, preferably 2-50% by weight, more preferably 3
~30% by weight. If the amount used is less than 1% by weight,
The improvement in solvent resistance and heat resistance of the finally obtained synthetic resin coating layer will not be sufficiently improved. On the other hand, if it exceeds 60% by weight, not only the final coating layer obtained becomes brittle, but also the fluidity of the synthetic resin material used to form the coating layer tends to deteriorate, which is not preferable. Further, the polymer content of the partially crosslinked gel polymer is 4 to 62% higher than the polymer content in the mixture, so that the total polymer content does not exceed 80% by weight, preferably 62% by weight.
% by weight, preferably 10-62% by weight, most preferably 15-62% by weight. If the increase in the polymer content of the partially crosslinked gel-like polymer with respect to the polymer content in the mixture is less than 4% by weight, the product will exhibit a gel-like appearance and will be inconvenient to handle as a coating material. Become. On the other hand, if the value increases by 62% by weight or more, or if it exceeds the upper limit of 80% by weight, it tends to not exhibit good fluidity during molding, and is not preferred as a coating material. This partially crosslinked gel-like polymer is heated in a mold to polymerize and solidify the crosslinked methacrylic resin coating layer, which has light resistance,
Since it has excellent solvent resistance, heat resistance, and scratch resistance, it can improve the durability of laminated molded products. Further, the coating M can be colored and can have various thicknesses. Therefore, when providing a decorative member such as veneer, cloth, or leather between the covering layer and the base material, various types of decorative members such as veneer, cloth, and leather may be used depending on the combination of the type, color, pattern, etc. of the member and the color and thickness of the covering layer. Decorative expression is possible, which is advantageous in terms of design. When a decorative member is interposed, the monomers and polymers contained in the partially crosslinked gel polymer, which is the raw material for forming the coating layer, are filled into the minute gaps of the decorative member.
The covering layer is firmly attached to the decorative member. therefore,
It becomes possible to increase the thickness of the coating layer, and it becomes possible to improve the durability of the laminated molded product. The thickness of the coating layer is not particularly limited as long as it is thick enough to protect the surface of the decorative member and provide decorative expression, but is preferably 0.3 to 2 mm. If the thickness is less than 0.3 mm, it is not preferable because not only the protective effect of the decorative member is insufficient, but also the quality of the resulting laminate molded product is reduced. This crosslinked methacrylic resin may contain coloring agents such as dyes and pigments, ultraviolet absorbers, organic/inorganic fillers, etc., if necessary. The partially crosslinked gel polymer used to obtain such a crosslinked methacrylic resin coating layer is disclosed in Japanese Patent Application Laid-open No. 6
Publication No. 0-202128 or JP-A-62-1705
The crosslinked methacrylic molding material described in the above publication can be used, and (A) the crosslinkable monomer is 1 to 60% by weight.
and [B) 99 to 40% by weight of an unsaturated monomer which may be dissolved in the polymer, mainly consisting of alkyl methacrylate, is polymerized by heating in the presence of a polymerization initiator. It can be obtained by stopping the reaction at a stage where only a portion of the monomers present in the mixture has reacted without reacting. In this case, the content of the polymer present in the partially crosslinked gel polymer is, as described above, a mixture of the crosslinking agent and the unsaturated monomer that may be dissolved in the polymer, mainly consisting of the alkyl methacrylate. 4-62 than the polymer content in
% by weight, preferably 10-62% by weight, most preferably 15-62% by weight, and the total polymer content is desired to exceed 80% by weight, preferably 62% by weight. Forms of the partially crosslinked gel polymer include sheet,
Although it may be a rod or pellet, it is preferable to crush or knead it for the purpose of improving fluidity. In addition, 1 part by weight of the partially crosslinked gel polymer obtained as described above may contain 1 part by weight of a silica mainly composed of alkyl methacrylate and dissolved therein.
It is also possible to use a molding material in which fluidity, adhesion, etc. are improved by adding up to 100 parts by weight and kneading substantially uniformly. By using this, the following favorable effects can be imparted. (a) Fluidity is further improved and processing can be performed at low pressure. (b) Appropriate tackiness can be imparted. (C) Even when the total polymer content is relatively high, the adhesion of the coating layer can be improved. (d) When coloring the coating layer, uniform coloring can be achieved by mixing dyes and pigments into the coating, and generation of running patterns and uneven spot patterns can be prevented. Here, if the amount of the above-mentioned silica added exceeds 100 parts by weight, it is not preferable because the shape retention of the composition will not be maintained. In addition, the term "silicone which is mainly composed of alkyl methacrylate and may contain a dissolved polymer thereof" means a silica which contains a polymer of alkyl methacrylate or a monomer mixture containing alkyl methacrylate as the main component, and preferably 25 It has a viscosity of 4 to 50 voids, more preferably 6 to 20 voids, at °C, and may contain up to 50% by weight of a crosslinking agent if necessary. In that case, it is desirable to contain the same concentration of crosslinking agent as the partially crosslinked gel polymer. When the partially crosslinked gel polymer is not crushed, it can be carried out by using a mixer or a crusher. In some cases, it can be carried out using a mixing agitator such as a super mixer or a Henshil mixer. Here, ``substantially uniformly mixed wires J'' means that the sillage kneaded into the coating composition by the above-mentioned wire mixing method is kneaded to the extent that it does not separate and flow out when left at room temperature for a short time, This state can be achieved by stirring and mixing using a mixer for several minutes to about 15 minutes.
It is a monomer having an acryloyl group and the number of carbon atoms present between the (meth)acryloyl groups is 0 or less, preferably monomers represented by the following formulas (1) to (3), most preferably Preferably, 2,2-dimethylolpropane dimethacrylate is used in terms of transparency and fluidity. (1) -MA-0-(CHz) n O-MA[
Here, n is an integer of 3 to 6, and MA represents a methacryloyl group. ] [Here, R8 is H, CHs, C2R5. CH20H group, R2 is H, CH3, CH20H. CH20COC= CH2C However, R4 is H, CH3
represents the group of ), R5 represents H, CH, and R1, R
2 and R3 are not hydrogen at the same time, and (M)A represents a methacryloyl group or an acryloyl group. ] (3) -(M)A O(CH2CH20) n
(M)A [where n is 1 or 2, and (M)A represents a methacryloyl group or an acryloyl group. Similarly, the alkyl methacrylate may be methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, lauryl methacrylate, etc. alone or as a mixture, with methyl methacrylate being particularly preferred. The laminate molded product of the present invention is produced by disposing a decorative member or a primer on a base material, placing a methacrylic resin material thereon, and heating it under pressure, in which (A) is used as a molding material. 1 to 60% by weight of crosslinkable monomer, and (B)
A mixture consisting mainly of alkyl methacrylate and 99 to 40% by weight of an unsaturated monomer which may be dissolved in the polymer is partially polymerized in the presence of a polymerization initiator to reduce the total polymer content. It can be produced by using a partially crosslinked gel-like polymer with a polymer content increased by 4 to 62% by weight within a range not exceeding 80% by weight. For example, decorative members can be formed on a synthetic resin base material. A method of fixing the decorative member in advance with adhesive, etc., placing it in a mold, then placing a molding material made of a partially crosslinked gel polymer on top of the decorative member, closing the mold, and heating under pressure. , it can be molded using a simple method. The molding is carried out at 90-160°C, preferably 1
5-250 kg/cm at a temperature of 00-150°C
2. Preferably, it is carried out under pressure of 10 to 200 kg/Cm2. The molding material placed on the decorative member is subjected to the above pressure when it is in a flowing state following the closing of the mold, but since the shear rate during flow is slow, the decorative member may break. do not. Also, at this time, the monomer and/or polymer contained in the partially crosslinked gel polymer permeates into the minute gaps of the decorative member under heat and pressure.
Since the coating layer made of the partially crosslinked gel-like polymer and the decorative member adhere firmly, the coating thickness can be increased or controlled to any desired thickness, and durability can also be improved. becomes. In the laminate molded product of the present invention, a decorative member can be placed between the covering layer and the base material, as described above. There are no particular restrictions on the decorative components as long as they exhibit decorative properties, such as wood, veneer, cloth, paper, leather, stone, etc.
Printed films, pottery, shells, metals, paints, etc. When wood or veneer is used as a decorative component, the microscopic irregularities on the surface create the natural three-dimensional effect of natural wood. However, when directly coated with a cross-linked methacrylic resin molding material under pressure and heat, the microscopic irregularities are removed. In order to prevent this from happening, an acrylic paint film with good adhesion to crosslinked methacrylic resin can be provided as a protective layer on the surface of the wood or veneer. This provides the effect that the protective layer and the covering layer, which penetrate into minute gaps and firmly adhere to the decorative member, are firmly adhered to each other. In addition, if it is difficult for the monomers contained in the molding material to penetrate into the minute gaps of the decorative member, it is possible to form a protective layer with an acrylic paint that easily penetrates the decorative member. It is possible to improve the adhesion with. On the other hand, if monomers, etc. contained in the molding material permeate into the decorative component excessively, the decorative component becomes wet and the color of the underlying base material and adhesive of the decorative component becomes visible. However, if a protective layer of acrylic coating is provided, such a phenomenon can be prevented because the protective layer prevents excessive penetration of monomers, etc. Examples of such acrylic paints include cross-linked polymerizable coating compositions mainly containing polyfunctional (meth)acrylic compounds, such as cross-linked coating compositions containing at least two (meth)acryloyloxy groups per molecule. A coating composition consisting of a polymerizable compound, a mixture of the crosslinked polymerizable compound with other polymerizable monomers containing 30% by weight or more, or a partial polymer thereof is preferably used. A coloring agent and an organic/inorganic filler can be added to the acrylic paint as necessary. In addition, when a decorative member is not applied, or even if a decorative member is used, it is not large enough to cover the entire surface of the synthetic resin base material, the difference between the base material and the coating layer is A primer is interposed in the area where no decorative member is interposed. The primer is not particularly limited as long as it has adhesive properties to both the synthetic resin base material and the coating layer, and for example, an adhesive for bonding a decorative member to the base material may be used. Particularly preferred from the viewpoint of durability is a phenol urethane primer. The primer is applied to the substrate by means such as brushing or spraying. The synthetic resin coating layer is formed after the primer solvent has completely evaporated. Since the above-described molding method is used, the shape of the laminate molded product is not particularly limited as long as it can be set in a mold, and the degree of freedom in shape is large. The synthetic resin base material in the present invention has heat resistance that can withstand the molding temperature and pressure during the formation of the coating layer, is resistant to attack by monomers contained in the raw material for forming the coating layer, and has the ability to provide gloss for laminated molded products. Even if commercially available polishing agents, waxes, etc. used in . Examples of such resin materials include polyamide (PA), polybutylene terephthalate (PBT), and polyethylene terephthalate (
PET), or such crystalline resin and acrylonitrile-butadiene-styrene copolymer (A
BS), acrylonitrile/special acrylic rubber/styrene copolymer (AAS), acrylonitrile/ethylene-
Examples include materials whose main components are mixtures with amorphous resins such as propylene rubber-styrene copolymer (AES), acrylonitrile-styrene copolymer (AS), polyphenylene ether (PPE), and polycarbonate (PC). In particular, alloyed materials are preferred. Some of the more desirable materials are polyamide and polyphenylene ether alloys. These resin materials can also contain inorganic fillers such as talc, mica, wollastenite, calcium carbonate, and glass fiber. A synthetic resin base material that does not contain a crystalline resin is undesirable because it tends to be attacked by monomers during molding of the synthetic resin coating layer and cause foaming, flow, or deformation. The heat deformation temperature of the base resin necessary to withstand the molding temperature and pressure during coating layer formation is 90°C or higher, preferably 120°C.
℃ or higher. The heat deformation temperature can be adjusted by the inorganic filler and the like. Heat distortion temperature is ASTM D64
8 under a load of 18.6 kg/cm2. Furthermore, by approximating the coefficient of linear expansion of the synthetic resin base material to the coefficient of linear expansion of the coating layer, it is possible to prevent warpage of the laminated molded product and cracking and peeling of the coating layer. The coefficient of linear expansion can be adjusted by the inorganic filler and the like.

[Implementation-Example]

Next, test examples of the laminate molded product according to the present invention will be explained together with comparative examples. [Test Examples 1 to 9, Comparative Examples 1 and 2] ■ 95 parts by weight of methyl methacrylate monomer, 5 parts by weight of neopentyl glycol dimethacrylate, 1.4
(8) -P-Menthagene 0.01 part by weight, 2.2'-
001 parts by weight of azobis(4-methoxy-2,4-dimethylvaleronitrile), 0.3 parts by weight of 2,2-bis(t-butylperoxy)butane, 0.2 parts by weight of di-t-butyl peroxide, Mix and dissolve 0.1 part by weight of 2-(5-methyl-2-hydroxyphenyl)benzotriazole, inject into a cell assembled with two glass plates and a gasket at a spacing of 10 mm, and heat at 60°C. Polymerization was carried out for about 2 hours to obtain a partially crosslinked gel polymer. The polymer content of this partially crosslinked gel polymer was 38%. Furthermore, the coefficient of linear expansion of the polymer obtained by pressurizing and heating the partially crosslinked gel-like polymer is 6 to 9 x 10-'cm/c.
It was m/'C. ■Mold the synthetic resin and materials for the base material in Table 1 using a door wood grain panel base material mold, and make a piece with a length of 696 mm, width of 62 mm, and thickness of 3.
A base material of mm was obtained. Table 1 shows the coefficient of linear expansion of each base material. A decorative member was obtained by backing and reinforcing a camphor tree veneer with a thickness of 0.1 mm with a polyester nonwoven fabric with a thickness of 0.1 mm. Then, the decorative member was adhered to the synthetic resin substrate obtained in step (2) using a resol adhesive. ■ The synthetic resin base material with the decorative member adhered to the surface obtained in
60 g of the partially crosslinked gel-like polymer obtained in step (2) was crushed and placed in a sheet-like shape, the mold was closed, and the mold temperature was 130°C and the initial pressure was 40°C. ~50k
g/cm2 Medium pressure 100 kg/cm2, high pressure 20
Molding was carried out for a total of 3 minutes at 0 kg/cm2 to obtain a laminate molded product with a coating layer thickness of 1 mm. The laminated molded product obtained in step (3) was taken out from the mold, left to cool in air for 1 hour, and then the state of deformation was visually confirmed. The results are shown in Table 1. ■ ■ From Table 1, it can be seen that good laminated molded products without deformation etc. can be obtained by the present invention. [Test Example 10] A phenol urethane primer was coated on the surface of the same synthetic resin base material as in Test Example 6 without pasting a veneer, and it was set in the same strip-shaped mold as in Test Examples 1 to 9. Then, the same partially crosslinked gel polymer as in Test Examples 1 to 9 was placed thereon and molded under the same conditions. The obtained laminated molded product was taken out from the mold and subjected to a thermal cycle test. The test conditions were to hold the temperature at 80°C for 4 hours, then lower it to -40°C over 2 hours, hold it at that temperature for 4 hours, then heat it up to 80°C again over 2 hours, repeating the cycle 10 times. It is. The test results confirmed that no peeling occurred in this case. [Comparative Example 3 Test Example 10 except that the base material was set in the mold without being coated with the co-primer and the partial polymer was placed directly on it.]
A synthetic resin coating layer was molded using the same material and under the same conditions. When the obtained laminated molded product was subjected to a thermal cycle test under the same conditions as in Test Example 10, peeling was observed in this case. Effects of the Invention As is clear from the above description, according to the present invention, a monomer is contained in a synthetic resin base material mainly consisting of a crystalline resin or a mixture of a crystalline resin and a non-crystalline resin. Since the synthetic resin coating layer is formed by heating a fluid synthetic resin material in a mold to polymerize and solidify it, even if the shape of the synthetic resin base material is complex, A uniform and sufficient coating layer of any thickness can be obtained over the entire laminate molded product, and a highly durable laminate molded product can be obtained. Furthermore, since the coating layer is formed in the step -, not only quality control becomes easy, but also costs can be kept low. Furthermore, since the coating layer can be colored arbitrarily, a high degree of design can be imparted. In addition, since the synthetic resin base material has high chemical resistance and heat resistance, it will not be attacked by the monomer in the raw material for the coating layer or deformed by heat or pressure during the formation of the coating layer. Therefore, a laminate molded product with good appearance quality can be obtained. Furthermore, since a decorative member or a primer is interposed between the synthetic resin coating layer and the synthetic resin base material, the adhesion thereof is extremely good. Moreover, since the coefficients of linear expansion of these coating layers and the base material are made to be similar, changes in ambient temperature will not cause warping of the laminated molded product or cracking or peeling of the synthetic resin coating layer. disappears. Therefore, a laminate molded product having long-term durability can be obtained. Patent applicant Honda Motor Co., Ltd. Kuraray Co., Ltd. Moriroku Co., Ltd. Agent Patent attorney Yu Mori Shimohata

Claims (2)

[Claims] (1) A synthetic resin base material whose main component is a crystalline resin or a mixture of a crystalline resin and an amorphous resin and a synthetic resin material containing a monomer and having fluidity are heated in a mold. a synthetic resin coating layer formed by polymerization and solidification and laminated on the synthetic resin base material with a decorative member in between, the synthetic resin base material having a line similar to the synthetic resin coating layer. A laminate molded product characterized by having a high expansion rate. (2) A synthetic resin base material whose main component is a crystalline resin or a mixture of a crystalline resin and a non-crystalline resin and a synthetic resin material containing a monomer and having fluidity are heated in a mold. a synthetic resin coating layer formed by polymerization and solidification and laminated on the synthetic resin base material with a primer in between, the synthetic resin base material having a coefficient of linear expansion similar to that of the synthetic resin coating layer. A laminate molded product characterized by having.