JPS6241470B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a panel made by bonding a shingle material and a face material together using an adhesive. Conventionally, various methods are known for manufacturing the above-mentioned panels. For example, resorcinol formaldehyde resin, urea formaldehyde resin, polyvinyl alcohol, casein, starch, synthetic resin aqueous emulsion, or synthetic rubber emulsion is applied to one or both of the heel material and the face material, and the materials are laminated and pressed together at room temperature or with a hot press. There are ways to manufacture panels. However, with such a method, pressing at room temperature takes tens of minutes to several hours, making it impossible to manufacture panels continuously with high productivity, and pressing at high temperature requires too much pressure. Although the tightening time has been shortened to several tens of seconds to several minutes, it is still not possible to manufacture panels continuously and efficiently, and the quality of heat-sensitive sheathing materials and facing materials is impaired by high-temperature pressing. There is. Another manufacturing method is to apply a contact cement-type organic solvent-based synthetic rubber adhesive or water-based synthetic rubber adhesive to both sides of the shingle material and facing material, and then dry them separately by air drying, infrared drying, or radiant heat drying. There is a method of manufacturing a panel by drying the adhesive layer, then bonding them together, instantaneously pressing them, and integrating them. However, in this method, adhesive must be applied to both the sill material and the facing material, which is time-consuming. Since the adhesive layer is applied to both sides, the wood must be suspended in the air in order to dry the adhesive layer applied to both sides, which increases the drying space and reduces drying efficiency. seriously harms sexuality. In addition, in the method of using this contact cement type adhesive, once the shingle material and the facing material are pasted together, they are bonded instantly, so if the pasting position is misaligned, it cannot be corrected, resulting in a defective product. . In addition, adhesives containing water or other polar solvents are applied to one or both of the shingles and facing materials, and after they are bonded together, high frequency waves are applied while pressing to scatter and solidify the solvent, and/or chemical There is also a method of manufacturing a panel by integrating the face material and the sill material through a reaction, but in this case, a product with a large area such as a panel must be kept in a stationary state for several tens of seconds to several minutes. Because of this, it is not possible to produce continuously and with good productivity. Furthermore, there is a method of applying α-cyanoacrylate monomer-based adhesives or other acrylic monomer-based adhesives to one or both of the shingles and facing materials, and manufacturing panels by instantaneous pressing, but these types of adhesives are expensive. This is not only uneconomical, but also difficult to correct if the bonding position shifts. Furthermore, there is a method in which hot-melt adhesive is applied to the shingle material and/or the facing material for instant bonding, but with this method, if the bonding is not done instantaneously, the adhesive will cool and the adhesive strength will decrease. Another disadvantage is that it is impossible to correct the displacement of the bonding position after bonding, and the heat resistance of the panel is low because the heat resistance of the adhesive is low. The present invention provides a novel method for manufacturing panels that overcomes the drawbacks of the various known methods mentioned above.In manufacturing the panels, a water-based contact type adhesive is applied to one of the heel material or the facing material. While the adhesive is not dry, the sill material and the facing material are brought into contact to transfer a portion of the adhesive from one side to the other, and while the contact is maintained, high frequency or microwave is applied without pressure. It consists of applying pressure, drying, and then pressing to integrate the undercover material and the facing material. According to the present invention, the adhesive need only be applied to either the lining material or the facing material, which greatly simplifies the application process and improves productivity. for that purpose,
Apply a sufficient amount of adhesive to one of the parts to be coated with adhesive, and while the adhesive is still wet or fluid, attach the uncoated parts and apply the adhesive from one side to the other. Transfer to. This allows the adhesive to be applied indirectly to both parts. Further, in this state, the adhesive is still in a fluid state, so even if the bonding position is deviated from the predetermined position, the bonding position can be easily corrected. As the member to which the adhesive is applied, it is possible to select either the flap material or the face material, but generally the flap material is selected because it has a smaller application area. After the shingle material and the face material are pasted together, high frequency or microwave waves are applied to them in that state to volatilize the moisture, and then they are instantly pressed together to integrate them. As a result, drying time, drying space, and energy required for drying can be extremely reduced, and since high-frequency drying is used, only the moisture-containing adhesive layer is selectively heated. Ledge material is not damaged. Furthermore, since high frequency drying is used, adhesives in a sealed state, such as bonded adhesive layers, can be efficiently dried. The pressing after drying may be instantaneous or may be carried out continuously using, for example, a roll press, thereby significantly improving productivity. As described above, the present invention has made it possible to continuously produce panels from small to large panels at a high production speed in a small space, with simple processes, and with low energy consumption. The term "panel" used in the present invention refers to a planar body (flat surface, uneven surface) formed by adhering a surface material such as a sheet plate to one or both surfaces of a shingle material. The shingle materials include, for example, wood frames, plastic frames, plastic foam, paper honeycomb, insulation boards, glass fiber mats, and other composite bodies, and the facing materials include, for example, plywood, plastic film overlay plywood, and decorative paper. There are overlay plywood, natural wood decorative veneer overlay plywood and its painted products, painted plywood, melamine decorative board, dap sheet and dap sheet overlay plywood, PVC sheet, paperboard, decorative paper, textile fabric, etc., and for the reasons mentioned above, they are relatively popular. It is unique in that it can also use materials that are sensitive to heat. The water-based contact adhesive referred to in the present invention is an adhesive in which an adhesive resin exists in a dissolved or dispersed state in a solvent consisting of water or a water-containing solvent, and the moisture is completely removed by drying. Refers to adhesives that strongly bond and do not separate (i.e. have self-adhesive properties) as soon as they come into contact with surfaces coated with the same type of adhesive, even after the adhesive has run out. Examples include chloroprene rubber, NBR-chloroprene rubber, and acrylic resin. Includes latex such as copolymers and aqueous solutions.
These may contain resins alone or commonly used additives such as epoxy compounds, isocyanate compounds, halogen compounds, metal oxides, phenolic compounds, and melamine compounds. In contrast, organic solvent-based contact adhesives
It has poor high-frequency heating characteristics, and there is a risk of ignition and explosion due to the arc that rarely occurs during high-frequency heating, which is unfavorable in terms of occupational health. The member to which the adhesive is applied is preferably applied to the limp material in order to reduce the amount of adhesive used and simplify the application process. Lamination is carried out after application of the adhesive before it dries, preferably immediately after application, while the applied adhesive has fluidity. It is preferable that about half of the adhesive of the members is transferred to the corresponding position of the unapplied member. The bonded panels are preferably dried by passing through a high frequency drying tunnel while riding on a belt conveyor, and then being pressed using an instantaneous pressing machine such as a roll press. Examples of the present invention are shown below. Example 1 Three pieces of sawn lauan wood of 25 mm x 35 mm x 380 mm were placed laterally between two parallel frames of sawn lauan wood of 25 mm x 35 mm x 500 mm at three locations: the top, middle, and bottom. 450mm x installed at right angle to parallel frame member
A 500 mm rectangular wooden frame was used as the shingle material. The front side of this shingle material was made of alkyd-painted teak veneer decorative plywood (thickness 3 mm), and the back surface was made of paulownia veneer decorative plywood, cut into rectangles of the same size as the shingle material and glued with different adhesives to form the panel. manufactured and its strength was measured. The equipment used is as shown in Figure 1.
Consists of stations A to F. At station A, adhesive is uniformly applied to both sides of the shingle material 1 using a roll coater 2 at a rate of 140 g/m ² . Next, at station B, the shingle material 1 coated with adhesive is sandwiched between face materials 3 and 4 made of veneered decorative plywood, and the shingle material is positioned so as to be covered by the face materials 3 and 4 in just the right amount. Next positioned panel 5
A portion of the adhesive applied to the heel material is transferred to corresponding positions on the facing materials 3 and 4 by wind pressure from the direction indicated by the arrow. The panel 5 then passes through a radio frequency tunnel 6 at station D, during which water is removed from the adhesive layer by radio frequency (13.6 MHz, 20 kV, anode current 4 A) and it is dried. The panels leaving station D are pressed and integrated by passing between a pair of pressing rolls 7 at station E. Next, the integrated panel is trimmed to a fixed length on a conveyor 8 at a station F using a double saw or the like. The line speed throughout the entire process was 20 m/min. The results are shown in Table-1.

[Table] As is clear from Table 1, the method of the present invention uses aqueous contact cement such as Panel Master 140-8003 (manufactured by Kanebo NSC) alone,
It can only be used with adhesives containing additives such as some resins that cause a crosslinking reaction with urea-formalin resin adhesives, which are generally used as high-frequency adhesives, and acetic acid vinyl emulsion adhesives. I couldn't glue it. This is because it dries at station D without clamping.
This is because the adhesive applied here hardens without contact, so even if it is pressed by station E, it will no longer adhere. However, in the case of water-based contact cement (140-8003), water is quickly scattered because it dries without being compressed at station D, and because it is a contact cement type, it is compressed at station E after drying. It is immediately and strongly bonded. The physical properties of the adhesive used are as follows. Panel Master 140-8002: Main component Chloroprene rubber Properties Aqueous latex viscosity 10000-15000cps PH 7-9 Yodozol 22A316: Main component Polyglycidyl ether compound Properties Uniform liquid viscosity 500-1000cps/30℃ Solid content 95% Elastron E -37: Main component polyurethane property Aqueous solution solid content 25% PH 4-6 BRL2260: Main component alkylphenol compound property Status Milky white emulsion solid content 50-60% PH 7-8 Example 2 The limp wood used in Example 1 and using surface material,
Identical panels were manufactured in the same manner using the apparatus shown in FIG. For comparison, we applied the adhesive to both the heel material and the facing material using a different method, manufactured panel materials using the same process, and compared the required equipment, personnel, desired amount of adhesive, application time, etc. . The results are shown below. (1) Example of the present invention Application method After applying only to the lumber with a roll spreader,
By pressing it with scissors on the facing material, a part of the adhesive on the heel material was transferred to the corresponding position on the facing material. Required equipment: 1 roll spreader Applicator: 1 person Amount of adhesive required: 21g per panel Application time: 1.5 seconds per panel (2) Comparative example 1 Application method Use a roll spreader to both cover and facing materials Applied separately. Required equipment: 1 roller spreader for lining material, 1 roll spreader for facing material Number of people applying: 2 people Required amount of adhesive: 42g per panel, adhesive can be applied to unnecessary parts of facing material Become. Application time 1.5 seconds per panel (3) Comparative example 2 Application method Spray coating was applied to the heel material and face material. Required equipment: 2 or more spray guns Applicator: 1 person Required amount of adhesive: 31.5g per panel, adhesive will scatter to unnecessary surfaces of the sheathing material and facing material. In order to apply it to both sides of the lumber, it is necessary to spray it while it is suspended in the air.
The space required increases. Coating time 15 seconds per panel (4) Comparative example 3 Coating method The lining material was applied using a roll spreader, and the facing material was applied separately using a screen coater. Required equipment: 1 roll spreader, 1 screen coating machine
Table: Number of people applying: 2 people Required amount of adhesive: 21g per panel Application time: 6 seconds per panel; line speed is slow. As described above, according to the present invention, panels can be manufactured with high productivity with minimum equipment costs, without waste of adhesive, and with minimum number of personnel. For the adhesive, Panel Master 140-8003 was used for the invention examples and Comparative Examples 1 and 3, and spray type Panel Master was used for Comparative Example 2.
140−8000 was used. The coating amount is 140 in the example of the present invention.
g/m ² , and in the case of double-sided coating, 70 g/m ² was applied on the flat surface. When applying adhesive to the heel material and facing material separately using a roll spreader as in Comparative Example 1,
Two roll spreaders are required because the thickness of the shingle material and the facing material are different. Since the facing material is thin, there was also the problem that the adhesive would get around to the decorative surface during application, causing stains. Also, by installing two spreaders, two coating workers were also required. Since the adhesive was applied to the entire surface of the panel, the amount of adhesive required per panel was twice that of the example of the present invention. Comparative Example 2 is a method commonly used for contact adhesives in which the adhesive is applied to both the heel material and the facing material using a spray gun. In addition to requiring at least two units, a large spray booth, duct equipment, and equipment for suspending the shingle materials were also required, making it approximately 10 times as long to coat each panel. Moreover, the adhesive was scattered by spraying, and the required amount reached about 1.5 times that of the example of the present invention. In Comparative Example 3, in order to minimize the amount of adhesive required, adhesive was applied to the hem material using a roll spreader, and to the face material using a screen printing machine that punched out only the portion that contacted the hem material. In this case, the required equipment and space became larger, the number of personnel increased, and the line speed was determined by the screen coating speed, so the total line speed was about four times as high as in the example of the present invention. Example 3 The panel manufacturing method of the present invention according to Example 1, the method of applying adhesive to both sides of the sill material and the facing material, and drying with high frequency under pressure (Comparative Example 1), Comparative Example 2) or a method of drying the adhesive layer with hot air (Comparative Example 3), bonding and pressing were compared. The results are shown below.

[Table] Comparative Example 1 not only requires personnel to perform the clamping process, but also requires a temporary stop of the panel, which significantly slows down the line speed. Furthermore, since the pressing jig must be made of wood or plastic with a low dielectric constant, it is expensive and easily damaged, and a separate recovery line for the jig after depressurization is required. Furthermore, if the material is dried while being compressed, the scattering of water will be poor and the drying time and energy consumption will be increased. In Comparative Example 2, the paint on the decorative surface was damaged because the entire surface was heated by infrared rays. Furthermore, once the shingle material and the face material are pasted together, the position of the pasting cannot be corrected due to the self-adhesive nature of the contact type adhesive, so mismatches are unavoidable. In contrast, in the example of the present invention, only the adhesive layer with high moisture content is selectively heated, so no damage to the paint on the decorative surface occurs, and since the adhesive is still in a fluid state, mismatching occurs. It could also be fixed easily. In Comparative Example 3, as in Comparative Example 2, in addition to the damage to the paint on the decorative surface and the occurrence of mismatches that cannot be corrected, hot air drying also resulted in the formation of a skin layer on the surface.
Since it prevents the subsequent scattering of moisture, there was a drawback that it took a long time to dry. Additionally, with both infrared rays and hot air, the surface materials must be hung in the air to dry, which requires additional equipment and time.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the apparatus and steps for carrying out the method of the invention. 1 is a shingle material, 2 is a roller coater, 3 and 4 are face materials, 5 is a panel, 6 is a high frequency drying tunnel, 7 is a pressure roller, and 8 is a conveyor.

Claims (1)

[Claims] 1. When manufacturing a panel, a water-based contact adhesive was applied to either the shingle material or the facing material, and the adhesive was applied by bringing the shingle material and the facing material into contact while the applied adhesive was not yet dry. A part of the adhesive is transferred from the other material to the unadhesive material, and high frequency or microwave is applied without pressure while maintaining the contact state, and after drying, pressure is applied. , a panel manufacturing method characterized by integrating a shingle material and a facing material.