JP2006218640A - Manufacturing method of decorative fixture member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a decorative fixture member capable of continuously producing the decorative fixture member excellent in appearance and capable of suppressing the peeling of veneer at the time of processing or the peeling of veneer caused by the effect of heat or water and capable of more enhancing the productivity of the decorative fixture member than before. <P>SOLUTION: The decorative fixture member is manufactured by clamping a laminate, which is obtained by coating a base material with a reactive hot melt adhesive melted under heating, placing the veneer on the coated surface of the base material and subsequently placing a flat plate on the veneer under pressure using at least a pair of press rolls or press belts and laminating the base material and the veneer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a decorative member in which a substrate and a veneer are bonded using a reactive hot melt adhesive.

  In recent years, in the field of architecture, cosmetics made by attaching decorative materials such as decorative paper, vinyl chloride sheets, and veneer to base materials such as wood, plywood, particle board, and MDF for the purpose of protecting the base material and improving aesthetics. The member is often used as a flooring material, a wall material, a ceiling material or the like. In particular, the demand for a decorative member having a veneer bonded to a base material is increasing because it has a high-grade appearance.

  However, since the veneer is a thin slice of natural wood, there is a problem that wrinkles are easily generated or cracked when force is applied depending on the temperature and humidity conditions in the atmosphere. Therefore, the protruding plate is usually stuck to the base material in the same manner as the method adopted as a step of sticking the decorative paper to the base material, that is, the method of continuously sticking the decorative paper coated with an adhesive to the base material. If it tries to match, the crack of a veneer etc. will arise, and it may cause the appearance defect of the resulting cosmetic work member.

  Methods for pasting a veneer and a substrate without causing poor appearance have been studied conventionally. For example, an ethylene-vinyl acetate copolymer emulsion having a carboxyl group on the substrate, an organic extender, and an oxazoline ring. There is known a method for producing a natural wood-decorated wood board in which a natural wood thin veneer and a wood board are heat-pressure bonded using a water-based adhesive containing a polymer having the polymer (see, for example, Patent Document 1).

  However, amid the increasing demand for decorative products made by laminating the veneer and the base material, the method described in Patent Document 1, that is, a water-based adhesive is applied in the form of a plywood, and the veneer is superposed on the surface of the hot plate. In the method of hot pressing while applying pressure with a press, it is difficult to continuously mass-produce cosmetic products. In addition, the surface of the decorative member after bonding is often subjected to processing such as painting or cutting, but the water-based adhesive does not have sufficient initial adhesiveness, and further to some extent until final curing. Since time is required, if the processing is performed before the protrusion plate and the base material are sufficiently bonded, the protrusion plate may be peeled off due to stress or heat during the processing. In order to prevent exfoliation of the veneer at the time of processing, it is necessary to cure the decorative structure member after the hot-pressure bonding for about 1-2 days as a guideline in a state of being pressed by a deposition press or the like. In this method, there is a problem that it is impossible to improve the productivity of the decorative member, that is, to increase the efficiency of the production process.

  On the other hand, according to the method for manufacturing a flooring material in which a veneer that has been alternately and repeatedly subjected to a heat treatment and a cooling treatment in advance is bonded to a plywood with a hot-melt adhesive, a flooring material having a crack-resistant painted surface is provided. It has been reported that it can be produced (see, for example, Patent Document 2).

  However, in the method described in Patent Document 2, since a complicated work process in which a heat treatment and a cooling treatment are performed on the veneer in advance is required to prevent cracks and the like on the floor material surface. It is difficult to improve the performance. Further, the method described in Patent Document 2 is considered to be based on a bonding method using a hot press, that is, a batch type flat hot press method, and is not a method capable of continuously producing a decorative product. In such a method, it is difficult to improve the productivity of the decorative member.

JP 2003-147309 A Japanese Patent Laid-Open No. 2004-216811

  The problem to be solved by the present invention is that it is possible to continuously produce a decorative member that has excellent appearance and can suppress the peeling of the veneer during processing and the peeling of the veneer due to the influence of heat and water. It is an object of the present invention to provide a method for producing a decorative member that can be improved.

  The present inventors have made various studies to improve the productivity of decorative products, applied a reactive hot melt adhesive heated and melted as an adhesive on the surface of the base material, and mounted a veneer on the application surface. When the above-mentioned base material and the veneer were pasted together by pressing the placed one by a roll press method or a belt press method, it was found that the decorative member can be continuously produced.

  However, there is a problem that wrinkles and cracks derived from the veneer are partially generated on the surface of the decorative member obtained by the above method, and the appearance of the resulting decorative member is impaired.

  Therefore, the inventors, when pressing the base material and the projecting plate by a roll press method or the like, a pressure load other than the direction perpendicular to the base material or the projecting plate is a major factor of wrinkles and cracks generated on the projecting plate. It was found that it is possible to continuously produce a decorative product having excellent appearance by solving the above problems by pressing the projecting plate and the base material through a flat plate.

  That is, the present invention is a laminate obtained by applying a reactive hot melt adhesive heated and melted on a substrate, placing a veneer on the coated surface, and then placing a flat plate on the veneer. Is pressed using at least one pair of press rolls or press belts, and the present invention relates to a method for manufacturing a decorative member that bonds the base material and the protruding plate.

  ADVANTAGE OF THE INVENTION According to this invention, the cosmetics production member which is excellent in the external appearance and can suppress peeling of a veneer can be produced continuously, and it became possible to improve productivity rather than before.

  In the present invention, an adhesive layer is formed on the surface of the substrate by applying a reactive hot-melt adhesive that is heated and melted to the substrate, and then a veneer is placed on the adhesive layer, that is, on the adhesive-coated surface. Further, the present invention is a method for producing a decorative member in which the base material and the projecting plate are bonded together by pressing a flat plate on the projecting plate using at least a pair of press rolls or a press belt. .

  In the present invention, a veneer is placed on a flat plate, and an adhesive layer is formed by applying a reactive hot melt adhesive heated and melted on the surface of the veneer, that is, a surface to which the base material is bonded. A cosmetic structure in which the base material and the veneer are bonded to each other by pressing the base material on the adhesive layer, that is, the base material on the adhesive application surface, using at least one pair of press rolls or press belts. It is a manufacturing method of a member.

The present invention is characterized in that a flat plate is used when the substrate and the projecting plate are bonded together using a press roll or the like.
When a flat plate is not used, that is, when the reactive hot melt adhesive heated and melted is applied to the surface of the base material, and a protruding plate is stacked on the coated surface and pressed with a press roll or the like, the resulting decorative product In some cases, cracks and wrinkles derived from the veneer may occur on the surface of the plate.
Therefore, by using the flat plate at the time of pressing, it is possible to relieve the force acting in the direction causing the deviation between the protruding plate and the base material, and it is possible to suppress the occurrence of cracks and wrinkles derived from the protruding plate on the surface of the decorative member. .

  Various methods can be used as a method of applying the reactive hot melt adhesive to the substrate, and a method of applying with a roll coater is preferable. According to the roll coater, the reactive hot melt adhesive is applied onto the substrate only when the substrate comes into contact with the roll coater, and the application is stopped when the roll coater leaves the substrate. Can do. Therefore, the method of applying the reactive hot melt adhesive by the roll coater is not a continuous substrate like a sheet-like roll, but a plate-like one that is intermittently charged at a certain interval. It is a coating method suitable for the case. The application method using the roll coater is different from the application method using a spray or die coater, and can be applied without changing the setting of the apparatus when the size in the width direction of the substrate is changed.

The roll of the roll coater needs to be adjusted to be higher than the temperature at which the reactive hot melt adhesive melts, and the temperature is approximately 100 to 130 ° C., although it varies depending on the reactive hot melt adhesive used. It is preferable. The application amount of the reactive hot melt adhesive is preferably in the range of 50 to 200 g / m ^{2 in} consideration of adhesiveness and cost. If the temperature of the roll coater and the amount of the reactive hot melt adhesive applied to the substrate are within such ranges, the reactive hot melt adhesive applied to the substrate exhibits appropriate tackiness. Good initial bond strength and final bond strength can be expressed.

  Next, a projecting plate is placed on the adhesive-coated surface of the base material, and a flat plate having a size that completely covers the portion where the base material and the projecting plate are bonded together is stacked to form a four-layered multi-layered product. . The multilayer can be obtained by sequentially stacking a base material, a reactive hot melt adhesive, a veneer, and a flat plate. In the previous stage of the pressing step, the protruding plate and the base material constituting the multilayer are not completely fixed by the reactive hot melt adhesive. The multilayer is conveyed between rolls of a press having at least one pair of press rolls composed of two rolls, for example, and pressure is applied when passing between the rolls. As a result, the projecting plate and the base material are sufficiently fixed, and after the pressing, the flat plate is removed to obtain a decorative product having excellent appearance and the like.

  The pressing step may be performed in a state in which the base material constituting the multilayer object is in the lower side, and may be performed in a state in which the flat plate is in the lower side. That is, a reactive hot melt heated and melted is applied to the surface of a veneer placed on a flat plate, and a multilayer obtained by stacking a base material on the application surface is pressed by the same method as described above, and pressed. A decorative member can also be obtained by removing the flat plate after tightening.

  In the pressing step, a press machine having a pair of press belts including two press belts may be used instead of the pair of press rolls, and pressing may be performed by a belt press method. The press belt is composed of, for example, a belt made of resin such as rubber, metal, leather, and a plurality of rolls that rotate the belt.

  The pressing machine that can be used in the pressing step needs to have at least one pair of the press rolls or press belts for pressing the multilayered product. In order to prevent the peeling, it is preferable to use one having two or more pairs.

  The pressing step is a step necessary for completely bonding the base material and the protruding plate with the reactive hot melt adhesive. At this time, the pressure applied to the multilayer by the press roll or the like is preferably in the range of 1 to 30 MPa, and more preferably 10 to 20 MPa.

  As said press roll, what consists of resin, such as metals, such as iron, rubber | gum, and nylon, for example can be used.

  The diameter of the press roll and the roll constituting the press belt is preferably in the range of 50 mm to 1000 mm. By using a roll having a diameter within the above range, peeling of the veneer on the surface of the resulting decorative product member can be suppressed.

  The decorative product obtained by the production method of the present invention can be subjected to processing such as painting and cutting on the surface derived from the veneer. The decorative product obtained in the present invention does not need to be cured for 1 to 2 days before the processing such as cutting, and after the veneer and the base material are bonded together by the method of the present invention, the room temperature and the normal humidity Even if the surface of the decorative structure member is subjected to processing such as painting or cutting only by curing for 1 to 2 hours below, peeling of the veneer from the base material can be suppressed.

  According to the production method of the present invention, it becomes possible to continuously bond the base material and the veneer, and the productivity of the resulting cosmetic product is significantly improved compared to the conventional batch type flat hot press method. Can be made. Moreover, the decorative structure member obtained by the production method of the present invention has a good appearance without cracks and wrinkles of the veneer, and suppresses the veneer peeling during processing and the peeling of the veneer due to the influence of heat, water, etc. It can be done.

  Since the decorative structure member obtained by the production method of the present invention has no appearance of cracks or wrinkles on the veneer and has an excellent appearance, it can be used as a decorative structure member such as a floor, a ceiling, or a wall.

Next, the flat plate used in the present invention will be described.
The use of a flat plate in the present invention is important for suppressing the occurrence of wrinkles and cracks derived from the veneer plate when the base material and the veneer plate are bonded together by the press roll or the like. When a flat plate is used in the pressing step, it is possible to suppress the pressure acting in a direction other than the direction perpendicular to the base material or the veneer by the press roll or the like, and wrinkles derived from the veneer that can occur on the surface of the resulting decorative product member. Cracks can be sufficiently suppressed.

The flat plate used in the present invention is a plate having a smooth surface, and preferably does not deform even when a stress of 0.5 N / mm ² or less is applied to the surface. Here, deformation means that when a force of 0.5 N / mm ² is applied in a direction perpendicular to the surface of the flat plate, the surface of the flat plate is partially deformed and the smoothness of the flat plate is impaired.
As the flat plate, it is preferable to use, for example, a plate-like molded product made of metal, resin, wood, cement, or the like or a composite material thereof.
Examples of the metal that can be used for the flat plate include iron, aluminum, stainless steel, and steel plate.
Examples of the resin include thermosetting resins such as melamine resin, phenol resin, and fiber reinforced plastic (FRP), and thermoplastic resins such as acrylic resin, vinyl chloride resin (PVC), and polyethylene terephthalate resin (PET). Can be used.

  As the flat plate, those having a thickness of 1 mm to 100 mm are preferably used, and those having a thickness of 1.5 mm to 50 mm are preferably used. By using a flat plate having a thickness in the above range, wrinkles and cracks derived from the veneer plate that can occur on the surface of the resulting decorative product member can be suppressed, and good handleability of the flat plate can be maintained.

  The flat plate preferably has a surface area that completely covers a range in which the base material and the protruding plate are bonded together.

  Next, the base material and the veneer used in the present invention will be described.

  Examples of the base material used in the present invention include wood base materials such as wood, plywood, particle board, MDF (medium density fiber board), bakelite, acrylic, polyethylene terephthalate (PET), acrylic-butadiene-styrene copolymer (ABS). ), FRP, base materials made of resin such as vinyl chloride, metal base materials such as stainless steel and steel plates, ceramic base materials such as calcium silicate plates, slate plates and gypsum boards, and composite base materials thereof. it can. The shape of the base material is a plane in which the surface on which the projecting plate is bonded and the surface on the opposite side thereof are parallel, and may be, for example, a quadrangular prism or a cylinder.

  As the veneer that can be used in the present invention, for example, a natural wood such as firewood, firewood, oak, plug, etc., which has been thinly cut to a thickness of about 0.15 mm to 1.2 mm can be used. In addition, a non-woven fabric, a film made of polyethylene terephthalate, or the like may be used on the back surface of the protruding plate, that is, the surface to be bonded to the base material. In addition, as the protruding plate, a wood substrate obtained by laminating a plurality of types of wood is used by thinly cutting out a thickness of about 0.15 mm to 1.2 mm in a 90 ° direction from the lamination surface. You can also

  Next, the reactive hot melt adhesive used in the present invention will be described.

  The reactive hot melt adhesive used in the present invention is solid at room temperature, but melts by heating and can be applied, and is applied in a melted state and solidifies when cooled and exhibits adhesiveness.

  The reactive hot melt adhesive can exhibit excellent initial adhesive strength due to the cohesive strength of the resin when the molten resin cools. In addition, the reactive hot melt adhesive undergoes a cross-linking reaction when it is cured, so that it has excellent final adhesive strength and is less susceptible to lowering of adhesive strength due to the influence of heat and water, so-called excellent heat resistance and water resistance. An adhesive layer can be formed.

  The reactive hot melt adhesive enters a molten state at a relatively low temperature of about 100 to 130 ° C. Therefore, adverse effects on the base material due to heat, for example, deformation or discoloration of the base material, when the base material and the projecting plate are bonded with the reactive hot melt adhesive can be suppressed to a minimum.

  Examples of the reactive hot melt adhesive that can be used in the present invention include a moisture curable reactive hot melt adhesive comprising an isocyanate group-containing urethane prepolymer as a reactive functional group, and an alkoxysilyl group as a reactive functional group. Silane cross-linkable reactive hot melt adhesive containing urethane prepolymer, UV curable reactive hot melt adhesive and electron beam curable reactive containing compound having functional group that reacts with UV or electron beam A hot melt adhesive etc. are mentioned, These can be used individually or can be used in combination of 2 or more types.

  Among the reactive hot melt adhesives, use of a moisture curable reactive hot melt adhesive comprising an isocyanate group-containing urethane prepolymer has excellent initial adhesive strength, final adhesive strength, and curing. It is preferable because later heat resistance and the like can be expressed.

  As the moisture curable reactive hot melt adhesive, for example, a urethane prepolymer having an isocyanate group at the molecular end, or a urethane prepolymer having an alkoxysilyl group at the molecular end, if necessary, is used. Can do. In general, many urethane prepolymers have a relatively low molecular weight, but those skilled in the art also refer to those having a number average molecular weight of several tens of thousands as urethane prepolymers. It includes a urethane prepolymer having a number average molecular weight of tens of thousands.

  Among the urethane prepolymers described above, the moisture-curable reactive hot melt adhesive containing a urethane prepolymer having an isocyanate group at the molecular end reacts with moisture (humidity) contained in the veneer. The final adhesive strength and the heat resistance after curing can be expressed.

  The isocyanate group-containing urethane prepolymer that can be used in the present invention reacts various polyols and polyisocyanates described below under the condition that the isocyanate group of the polyisocyanate is excessive with respect to the hydroxyl group of the polyol. Can be manufactured.

  Examples of the polyol include polyester polyols, polyether polyols, acrylic polyols, polycarbonate polyols, polyolefin polyols, castor oil polyols, polyhydric alcohols and copolymers thereof, and these are used alone or in combination of two or more. be able to.

  As the polyol, polyester polyol is preferably used. As the polyester polyol, for example, a polyester polyol obtained by reacting a linear aliphatic diol and a linear aliphatic dicarboxylic acid can be used.

  As the linear aliphatic diol, for example, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 10-decanediol and the like can be used. 6-hexanediol, 1,8-octanediol, 1,10-decanediol can be used.

  As the linear aliphatic dicarboxylic acid, for example, succinic acid, adipic acid, sebacic acid, dodecamethylene dicarboxylic acid and the like can be used, and preferably sebacic acid and dodecamethylene dicarboxylic acid can be used.

  The combination of the linear aliphatic diol and the linear aliphatic dicarboxylic acid can be selected as appropriate. For example, 1,6-hexanediol is used as the linear aliphatic diol, and the linear aliphatic dicarboxylic acid is used. It is preferable to use a crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. such as a long-chain aliphatic polyester polyol obtained by reacting adipic acid, 1,12-dodecanedicarboxylic acid or sebacic acid as the acid.

  The crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. is preferably used in an amount of 10 to 60% by mass based on the total amount of polyol and polyisocyanate used when the urethane prepolymer is produced. It is more preferable to use mass%. By using the crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. only within the above range, the initial adhesiveness, adhesive strength, and durability (heat resistance, etc.) of the adhesive layer constituting the resulting decorative product member Can be improved.

  As the polyester polyol that can be used in producing the urethane prepolymer, the crystalline polyester polyol having a melting point of 40 ° C to 130 ° C and an amorphous property having a glass transition temperature in the range of -70 ° C to -10 ° C. It is preferable to use a polyester polyol in combination. The polyester polyol having a glass transition temperature in the range of −70 ° C. to −10 ° C. is used in a range of 10 to 60% by mass with respect to the total amount of polyol and polyisocyanate used in producing the urethane prepolymer. It is preferable. The reactive hot melt urethane adhesive obtained by using an amorphous polyester polyol having a glass transition temperature in the range of −70 ° C. to −10 ° C. within the above range has a suitable length of open time. It is preferable because wrinkles and cracks originating from the veneer on the surface of the decorative member that can occur in the pressing step can be suppressed and the heat resistance of the adhesive layer can be improved.

  Examples of the amorphous polyester polyol having a glass transition temperature in the range of −70 ° C. to −10 ° C. include, for example, o-phthalic acid, terephthalic acid, and adipic acid as a dicarboxylic acid component, and ethylene glycol, propylene glycol as a diol component, What is obtained by combining hexanediol, neopentyl glycol, etc. in a timely manner and subjecting them to a condensation reaction can be used.

  Polyether polyols can also be used as polyols that can be used when producing the urethane prepolymer. As the polyether polyol, for example, various kinds of known polyols such as a low molecular weight alcohol and the polyester polyol are used as an initiator, and one or more selected from ethylene oxide, propylene oxide, butylene oxide, styrene oxide, and the like, Examples thereof include ring-opening polymers obtained by ring-opening polymerization. Moreover, the ring-opening addition polymer obtained by adding (gamma) -butyrolactone, (epsilon) -caprolactone, etc. to the polyether-type diol of the obtained ring-opening polymer can also be used.

  The polyether polyol is preferably used in combination with the polyester polyol having a melting point of 40 ° C. to 130 ° C. The polyether polyol that can be used at this time is a glass transition in the range of −10 ° C. to −70 ° C. It is preferable to use one having a temperature. The polyether polyol having a glass transition temperature in the range of −10 ° C. to −70 ° C. is used in the range of 10 to 60% by mass with respect to the total amount of polyol and polyisocyanate used in producing the urethane prepolymer. It is preferable that use in the range of 20 to 45% by mass can suppress the wrinkles and cracks derived from the veneer that can occur on the surface of the resulting decorative member, and can improve the heat resistance of the adhesive layer. Is more preferable.

  Moreover, as a polyol which can be used when manufacturing the said urethane prepolymer, the polyester polyol which has an aromatic cyclic structure can also be used. As the polyester polyol having the aromatic cyclic structure, for example, a polyester polyol obtained by a condensation reaction of an aromatic polycarboxylic acid and a low molecular weight aliphatic polyol can be used.

  Examples of the aromatic polycarboxylic acid that can be used in producing the polyester polyol having the aromatic cyclic structure include phthalic acid, isophthalic acid, terephthalic acid, hexahydroisophthalic acid, and the like. Alternatively, two or more types can be used in combination.

  Examples of the low molecular weight aliphatic polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,2-dimethyl-1, 3-propanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane-1,4- Diol, cyclohexane-1,4-dimethanol and the like can be used.

  The polyester polyol having an aromatic cyclic structure is obtained by combining ethylene glycol and neopentyl glycol as the low molecular weight aliphatic polyol and isophthalic acid or terephthalic acid as the aromatic polycarboxylic acid in a timely manner and subjecting it to a condensation reaction. It is preferred to use the polyester polyols obtained.

  The polyester polyol having the aromatic cyclic structure is a crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. and the −10 ° C. to −70 ° C. as a polyol used when the urethane prepolymer is produced. It is preferable to use in combination with an amorphous polyester polyol having a glass transition temperature in the range of −10 ° C. to −70 ° C. or an amorphous polyether polyol having a glass transition temperature in the range of −10 ° C. to −70 ° C. At this time, the polyester polyol having an aromatic cyclic structure is preferably used in a range of 10 to 40% by mass with respect to the total amount of polyol and polyisocyanate used in producing the urethane prepolymer. Use in the range of 15% by mass is more preferable in terms of expressing suitable initial adhesive strength and open time.

  Examples of the polyisocyanate that can be used in producing the urethane prepolymer include phenylene diisocyanate, tolylene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (4,4′-MDI), and 2,4-diphenylmethane diisocyanate. (2,4-MDI), aliphatic diisocyanates such as aromatic diisocyanates such as naphthalene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate Diisocyanates and their modified carbodiimides may be used. These may be used alone or in combination of two or more. It can be. Among these, it is preferable to use the 4,4'-MDI or 2,4-MDI having a low vapor pressure during heating and melting.

  The ratio of the polyol and polyisocyanate used in producing the urethane prepolymer is the equivalent ratio of the isocyanate group of the polyisocyanate to the hydroxyl group of the polyol (hereinafter referred to as the equivalent ratio of [isocyanate group / hydroxyl group]. Is preferably in the range of 1.1 to 5.0, and more preferably in the range of 1.5 to 3.0.

  The mass ratio of the isocyanate group-containing urethane prepolymer in the moisture-curable reactive hot melt adhesive and the urethane prepolymer having an alkoxysilyl group at the molecular end is excellent initial adhesive strength, final adhesive strength, And when expressing the outstanding heat resistance after hardening, it is preferable to exist in the range of 30-100 mass%.

  It is preferable that the mass ratio of the isocyanate group in the urethane prepolymer is in the range of 1.5 to 3.5% by mass. When the mass ratio of the isocyanate group is within the above range, the melt viscosity of the moisture curable reactive hot melt adhesive is in a suitable range, and good coating suitability is obtained, and initial cohesion and initial adhesive strength are obtained. A moisture-curable reactive hot melt adhesive excellent in the above can be obtained.

  The reactive hot melt adhesive used in the present invention is 6000 to 40,000 mPa · s at 125 ° C. in order to improve the coating property when applied to the substrate surface and the adhesion between the substrate and the veneer. It preferably has a melt viscosity in the range of s.

  The reactive hot melt adhesive preferably has a melting temperature of, for example, 100 to 130 ° C. in order to improve the coating property when applied to the substrate surface.

  As described above, if the reactive hot melt adhesive is used in the present invention, the curing reaction can be advanced quickly, and the cosmetic product after pressing is heat and water resistant without curing for a long time. It is possible to form an excellent adhesive layer.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawings described below are one embodiment of the present invention, and the position of each part is not limited as long as the object is achieved.

  Examples of the present invention are shown below.

<Appearance>
The surface of the cosmetic product immediately after pressing was visually observed to evaluate its appearance.

Judgment criteria for appearance ○: There is no peeling, cracking and wrinkling of the veneer throughout.
(Triangle | delta): Peeling of a veneer, a crack, and a wrinkle are seen in part.
X: Peeling, cracking and wrinkling of the veneer are observed throughout.

<Mechanical post-workability>
A groove having a depth from the veneer surface side of the decorative member immediately after the base material and the veneer plate were pressed to the base material was cut using a panel saw. The groove after cutting was observed from the protruding plate side, and the presence or absence of peeling, cracking and wrinkling of the protruding plate around the groove was observed.

Judgment criteria for mechanical post-workability ○: There is no peeling, cracking and wrinkling of the veneer throughout.
(Triangle | delta): Peeling of a veneer, a crack, and a wrinkle are seen in part.
X: Peeling, cracking and wrinkling of the veneer are observed throughout.

<Thermal post-workability>
After pressing the base material and the veneer, the cosmetic product cured at 20 ° C. in an atmosphere of 60% relative humidity for 1 hour was left in an atmosphere at 80 ° C. for 2 hours. After leaving, the groove of the depth from the veneer surface side of the decorative member to the base material was cut using a panel saw. The groove after cutting was observed from the protruding plate side, and the presence or absence of peeling, cracking and wrinkling of the protruding plate around the groove was observed.

Judgment criteria for thermal post-workability ○: There is no peeling, cracking and wrinkling of the veneer throughout.
(Triangle | delta): Peeling of a veneer, a crack, and a wrinkle are seen in part.
X: Peeling, cracking and wrinkling of the veneer are observed throughout.

<Heat resistance>
The cosmetic product having the adhesive layer completely cured by standing at 20 ° C. in an atmosphere with a relative humidity of 60% for 72 hours was left in an atmosphere at 80 ° C. for 192 hours. It was visually determined whether or not the veneer peeled or cracked in the decorative product after being left.

Criteria for heat resistance ○: There is no peeling, cracking and wrinkling of the veneer throughout.
(Triangle | delta): Peeling of a veneer, a crack, and a wrinkle are seen in part.
X: Peeling, cracking and wrinkling of the veneer are observed throughout.

<Water resistance>
A cosmetic product in which the adhesive layer was completely cured by standing for 72 hours in an atmosphere of 60% relative humidity at 20 ° C was immersed in warm water at 70 ° C for 2 hours. Next, it was visually determined whether or not peeling or cracking of the veneer had occurred in the cosmetic product after drying for 3 hours with a drier adjusted to 60 ° C. after the immersion.

Criteria for water resistance ○: There is no peeling, cracking and wrinkling of the veneer throughout.
(Triangle | delta): Peeling of a veneer, a crack, and a wrinkle are seen in part.
X: Peeling, cracking and wrinkling of the veneer are observed throughout.

(Production Example 1) Reactive Hot Melt Adhesive Preparation Example A 2-liter four-necked flask was derived from 190 parts by mass of polypropylene glycol having a number average molecular weight of 2000 and 1,12-dodecanedioic acid / 1,6-hexanediol. 380 parts by weight of an aliphatic polyester polyol having a hydroxyl equivalent weight of 1750, 200 parts by weight of an aliphatic polyester polyol having a hydroxyl equivalent weight of 2000 derived from adipic acid / 1,6-hexanediol, and ethylene glycol / neopentyl glycol / isophthalic acid / terephthalate 380 parts by mass of an aromatic polyester polyol having an acid-derived hydroxyl equivalent weight of 1500 is mixed and heated at 100 ° C. under reduced pressure until the water content in the 2-liter 4-necked flask reaches 0.05% by mass. Dehydrated.

  Next, after cooling them to 70 ° C., 226 parts by mass of 4,4′-diphenylmethane diisocyanate is added, the temperature is raised to 120 ° C., and the reaction is continued for 3 hours until the mass ratio of the isocyanate groups of the urethane prepolymer to be formed becomes constant. Thus, a urethane prepolymer (number average molecular weight 1622) having an isocyanate group at the molecular end was obtained.

  To the obtained urethane prepolymer having an isocyanate group at the molecular end, 1 part by mass of 2,2′-dimorpholinodiethyl ether (trade name: U-CAT 660M, manufactured by San Apro) as an additive is added and stirred uniformly. Thus, a reaction in which the mass ratio of isocyanate groups in the urethane prepolymer is 2.3 mass% and the melt viscosity at 125 ° C. measured using a cone plate viscometer (ICI type, 20P cone) is 11000 mPa · s. Hot melt adhesive was obtained. The isocyanate group content is determined by adding an excess of amine to the urethane prepolymer having an isocyanate group at the molecular end, causing the isocyanate group to react, and then titrating the remaining amine with hydrochloric acid. The mass ratio of the isocyanate group in the inside was determined.

Example 1
Drawing 3 is a mimetic diagram showing the manufacturing method of the decorative work member concerning one embodiment of the present invention. In this production method, the reactive hot-melt adhesive obtained in Production Example 1 was used as a roll coater 5 (Made under Matsushita, DTW-420) consisting of a pair of rolls capable of adjusting the temperature in FIG. The reactive hot melt adhesive flows down on the surface of the substrate 1 (plywood: 12 mm thick, 300 mm wide, 1800 mm long) at a surface temperature of 120 ° C. and a roll rotating speed of 20 m / min. / M ^{2 was} applied.

  Next, the veneer 3 (ply material: thickness 0.3 mm, width 310 mm, length 1820 mm) is immediately placed on the surface to which the reactive hot melt adhesive is applied, and the flat plate 4 (plywood) is further placed on the veneer. : 12 mm in thickness, 320 mm in width, 1820 mm in length) were stacked to form a multilayer 7 (FIGS. 1 and 2). This was pressed with a pair of iron press rolls 6 at a pressure of 12 MPa, and the base material and the protruding plate were bonded together, and then the flat plate 4 was removed to obtain a decorative member (FIG. 4).

(Example 2)
The reactive hot melt adhesive obtained in Production Example 1 was applied to the roll coater 5 (Matsushita Kogyo Co., Ltd., DTW-420, press roll surface) composed of a pair of rolls capable of adjusting the temperature shown in FIG. It flowed down at a temperature of 120 ° C. and a rotational speed of the roll of 20 m / min, and was applied onto the base material 1 (plywood: thickness 12 mm, width 300 mm, length 1800 mm) at 120 g / m ² .
Next, on the application surface of the reactive hot-melt adhesive, the protruding plate 3 (Nara material: thickness 0.3 mm, width 310 mm, length 1820 mm) is immediately placed, and the flat plate 4 (plywood: thickness 12 mm, Multilayer 7 was obtained by stacking 320 mm in width and 1820 mm in length). It was pressed using a press belt at a pressure of 10 MPa, and the base material 4 and the projecting plate were bonded together, and then the flat plate 4 was removed to produce a decorative member.

(Example 3)
A cosmetic product is manufactured in the same manner as in Example 1 except that the flat plate used when pressing the base material and the protruding plate is changed to (acrylic plate: thickness 6 mm, width 320 mm, length 1820 mm). did.

Example 4
A decorative member is prepared in the same manner as in Example 1 except that the flat plate used for pressing the base material and the protruding plate is changed to (steel plate: thickness 1.5 mm, width 320 mm, length 1820 mm). Manufactured.

(Comparative Example 1)
A cosmetic work member was produced in the same manner as in Example 1 except that a flat plate was not used when pressing the base material and the protruding plate. The surface of the obtained decorative structure member had a remarkable crack of the veneer, and peeling of the veneer was observed in part. Therefore, evaluation of mechanical workability etc. is not performed.

(Comparative Example 2)
The reactive hot melt adhesive obtained in Production Example 1 is applied onto the substrate 1, and the protruding plate 3 is overlaid on the coated surface, and flat pressing is performed at a pressure of 10 kg per square centimeter at a temperature of 70 ° C. for 1 minute. Then, a decorative product was manufactured.

  According to the flat press method described in Comparative Example 3, one decorative member can be manufactured per minute, whereas according to the method described in Example 1, five decorative members are manufactured per minute. The cosmetic product member that can be obtained is excellent in various evaluations, and various evaluation results are shown in Table 1 below.

* Slight wrinkles that do not cause a problem in practice enter part of the periphery of the substrate.

The schematic diagram of the multilayer object 7 which consists of the base material 1, the adhesive bond layer 2, the protrusion board 3, and the flat plate 4 is shown. A cross-sectional view of a multilayer object 7 composed of a base material 1, an adhesive layer 2, a veneer plate 3 and a flat plate 4 is shown. The schematic of the process of manufacturing a makeup | decoration structure member by the roll press method is shown. A cross-sectional view of the resulting cosmetic production member 8 is shown.

Explanation of symbols

1 Base material 1
2 Adhesive layer 2 made of reactive hot melt adhesive
3 Veneer 3
4 Flat plate 4
5 Roll coater 5
6 Press roll 6
7 Multi-layered product 7 composed of a base material 1, an adhesive layer 2, a protruding plate 3 and a flat plate 4
8 Make-up product 8

Claims (9)

At least one pair of press rolls or presses that apply a reactive hot-melt adhesive heated and melted on a substrate, place a veneer on the coated surface, and then place a flat plate on the veneer A method for producing a decorative member in which the base material and the protruding plate are bonded together by pressing with a belt. At least one pair of press rolls or presses, in which a projecting plate is placed on a flat plate, and then a reactive hot melt adhesive heated and melted is applied onto the projecting plate and a substrate is placed on the coated surface. A method for producing a decorative member in which the base material and the protruding plate are bonded together by pressing with a belt. The manufacturing method according to claim 1 or 2, wherein the flat plate is not deformed when a force of 0.5 N / mm ² is applied in a direction perpendicular to the surface of the flat plate. The manufacturing method according to claim 1, wherein the press roll has a diameter in a range of 50 mm to 1000 mm. The manufacturing method according to claim 1 or 2, wherein a pressure applied by the press roll or press belt in the pressing step is in a range of 1 to 30 MPa. The production method according to claim 1 or 2, wherein the reactive hot melt adhesive contains an isocyanate group-containing urethane prepolymer obtained by reacting a polyisocyanate and a polyol. The manufacturing method according to claim 6, wherein the isocyanate group-containing urethane prepolymer is obtained by reacting a crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. with polyisocyanate. The isocyanate group-containing urethane prepolymer comprises a crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C., an amorphous polyester polyol or polyether polyol having a glass transition temperature of −70 ° C. to −10 ° C., and poly The production method according to claim 6, which is obtained by reacting isocyanate. 10 to 60% by mass of a crystalline polyester polyol having a melting point of 40 ° C. to 130 ° C. with respect to the total amount of the polyol and the polyisocyanate, and a glass transition of −70 ° C. to −10 ° C. The manufacturing method of Claim 6 which is a thing obtained by using 10-60 mass% of amorphous polyester polyol or polyether polyol which has temperature.

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