JP6085548B2 - Glulam production method - Google Patents

Description

  The present invention relates to a method for manufacturing a laminated material that can avoid an adhesion failure phenomenon due to drying of an adhesive, particularly in a high temperature working environment such as in summer, in the manufacturing process of the laminated material.

  Conventionally, the length, width, and thickness of lamina (grind board, strip board) or small timber made from red pine, larch, fir, spruce, and other logs are arranged in parallel in the fiber direction. A laminated material with increased strength is produced by assembling and adhering in the vertical direction to form a square or thick plate material (see, for example, Patent Document 1 or Patent Document 2). As the adhesive used in the production of these laminated materials, a resorcinol-based resin adhesive, an aqueous polymer isocyanate-based adhesive capable of obtaining high strength without releasing formaldehyde, and the like are mainly used ( For example, see Patent Document 3 or Patent Document 4).

Japanese Patent Laid-Open No. 2001-150412 (paragraphs [0002] and [0003]) JP 2007-268731 (paragraphs [0001], [0002]) Japanese Patent Laid-Open No. 11-199848 (paragraph [0002]) JP 2001-253926 A (paragraphs [0020], [0021], [0041])

  In the manufacturing process of such a laminated material, in the working environment at a high temperature especially in summer, there is a problem that an adhesion failure occurs due to drying of the adhesive applied to the lamina surface. Conventionally, as a solution to the problem of poor adhesion due to drying of the adhesive in the summer, at the production site of laminated wood, the amount of adhesive applied is increased, or an adhesive with a low non-volatile component concentration is used only in the summer However, there is a problem that the manufacturing process is complicated and expensive because it is necessary to manage the switching of the brand of the adhesive depending on the season. On the other hand, the above-mentioned conventional Patent Documents 1 to 3 did not mention the influence on the adhesive performance of the adhesive due to the change of the surrounding environment to be manufactured and the method of manufacturing the laminated material including the method of using the adhesive. Moreover, according to the method described in the above-mentioned conventional patent document 4, the adhesive has excellent adhesive strength and water resistance, and has a good handling property with less risk of causing the adhesive skin when used in summer when the temperature is high. However, there was no mention about the influence on the adhesive performance of the adhesive by the change of the surrounding environment manufactured like patent documents 1-3, and the manufacturing method of a laminated material including the usage method of an adhesive.

  It is an object of the present invention to provide a method for manufacturing a laminated material that can avoid an adhesion failure phenomenon due to drying of an adhesive in a manufacturing process of the laminated material, particularly in a high temperature working environment such as in summer.

  As a result of intensive studies to achieve the above object, the present inventor sprayed an appropriate amount of water mist immediately after applying an aqueous adhesive with a high concentration of non-volatile components, even in summer when the ambient temperature is high. As a result, the present invention was completed.

According to a first aspect of the present invention, there is provided a method for producing a laminated material obtained by laminating and laminating a plurality of laminaes, and an aqueous adhesive having a non-volatile component concentration of 50 to 80% by mass on each adhesion surface of the laminas. After applying water and forming a water-based adhesive application surface, immediately after spraying water mist onto the water-based adhesive application surface at a rate of ² to 20 g / m ² and depositing it open, further laminating adhesive surfaces In addition, there is a method for producing a laminated material that is subjected to closed deposition and then pressed at room temperature.

  It is an invention based on the second aspect of the present invention, and is in a method for producing a laminated material having a Sauter average particle diameter d32 of water mist of 5 to 100 μm.

In the first aspect of the present invention, the ratio of ² to 20 g / m ² of water mist is applied to the surface of the water-based adhesive immediately after the water-based adhesive is applied to the adhesive surface of the lamina even in a high temperature atmosphere such as summer. By spraying with water, the adhesive surface is moistened, and at the same time, the environment around the lamina after application of the adhesive and the environment temperature and relative humidity in the lamination process are appropriately controlled. Even if an aqueous adhesive having a non-volatile component concentration of 50 to 80% by mass used at the temperature of the winter atmosphere is used as it is without preparing a new adhesive, it is satisfactory without causing poor adhesion due to the dry-out phenomenon. A laminated material having adhesive strength can be obtained. Here, the dry-out phenomenon refers to the case where moisture in the adhesive layer is directly absorbed into the wood after application of the adhesive, and further into the air from the adhesive layer surface or the end face of the adhesive layer after laminating. Since it evaporates and dries, it means that a problem of starting early curing occurs. In addition, the high temperature working atmosphere as in summer is about 30 to 40 ° C. and the relative humidity is about 40 to 80%, and the production process of laminated wood under such a working atmosphere is as high as in winter. Since the water-based adhesive composition having a non-volatile component concentration can be used positively, the manufacturing process is simplified, it is possible to secure a low-cost manufacturing cost without taking time, and the productivity of the laminated wood is also large. improves.

  In the second aspect of the present invention, since the Sauter average particle diameter d32 of the water mist is 5 to 100 μm, a uniform and dense water layer can be efficiently formed on the application surface of the aqueous adhesive. The problem of poor adhesion due to the dry-out phenomenon can be solved.

It is the figure which represented typically the manufacturing method of embodiment of this invention.

  Next, the form for implementing this invention is demonstrated.

  The present invention provides a method for manufacturing a laminated material that can avoid an adhesion failure phenomenon due to drying of an adhesive in a manufacturing process of the laminated material, particularly in a high-temperature working environment such as in summer.

  The characteristic configuration of the present invention is to spray water mist onto the lamina aqueous adhesive application surface immediately after the aqueous adhesive is applied to the lamina adhesive surface.

  Next, the manufacturing process of the laminated material will be described in detail based on the drawings.

  1A to 1D show the manufacturing process of the present invention. 1A shows an aqueous adhesive application process, FIG. 1B shows a water mist spraying process, FIG. 1C shows a laminating process, and FIG. 1D shows a pressing process.

  First, the water-based adhesive application process will be described with reference to FIG. Laminated wood is a laminate of laminated lamina, which is a single plate made of timber, and is laminated in the fiber direction. A laminated wood having a thickness of 1 cm or more is called laminated wood. Glued lumber is used as a pillar of building materials. The lamina described in the embodiment is a laminated material using a lamina having a thickness of 1 cm or more, a width of about 11 cm, and a length of several meters.

  For the coating method, a roll coater 100 suitable for application to a flat material, a spray suitable for application to a curved surface or a complicated shape, and an adhesive is extruded and applied from a slit-shaped die called a T-die. Various application methods such as an apparatus suitable for a relatively thin material can be applied. Here, a method of applying the water-based adhesive 102 to the lamina 101 by the roll coater 100 will be described.

The roll coater 100 is an apparatus that applies a water-based adhesive 102 to a material using a roll 103. Laminas are installed on the upper and lower four rolls 103 (two upper parts and two lower parts), and an aqueous adhesive 102 having a nonvolatile component concentration of 50 to 80% by mass is set between the two upper rolls 103. By rotating the upper and lower rollers 103, the long lamina 101 is moved at 50 to 100 m / min, and a uniform coating film of the water-based adhesive 102 is applied on the upper surface of the lamina 102 at a coating amount of 180 to 250 g / m ^2. Is formed.

  As the aqueous adhesive 102 used in the present invention, various known ones can be used without particular limitation. For example, a vinyl acetate resin emulsion, an acrylic resin emulsion, an acrylic / styrene resin emulsion, and a styrene / butadiene system are used. From an emulsion-type adhesive in which a synthetic resin polymer is dispersed in water, such as a resin latex, or a main agent composed of one or more of a water-soluble polymer and an aqueous emulsion, and an isocyanate compound such as 4,4′-diphenylmethane diisocyanate An aqueous polymer isocyanate-based adhesive containing a curing agent is preferable.

  Next, the water mist spraying process will be described with reference to FIG. After the aqueous adhesive 102 is applied, water mist is sprayed before the aqueous adhesive 102 does not dry. This is because when the water-based adhesive 102 is dried, the non-volatile component concentration set for bonding the lamina 101 changes. The spray of the water mist is desirably immediately after the application of the water-based adhesive 102.

Water mist is sprayed from the spray nozzle 201 at a rate of ² to 20 g / m ² while moving the lamina 101 after the application of the water-based adhesive 102.

  When water mist having a Sauter average particle diameter d32 of less than 5 μm is sprayed, the amount of water sprayed per unit area is reduced, and at the same time, the water mist itself is easily scattered over a wide area, and the applied water-based adhesive. It becomes impossible to supply dense and uniform moisture to the agent 102. In order to avoid this, if a large number of spray nozzles 201 are installed closer to the lamina surface, the operability deteriorates, and the distance between the spray nozzle 201 and the lamina surface is close, so that precise and uniform moisture can be supplied. Disappear. On the other hand, when water mist having a Sauter average particle diameter d32 of more than 100 μm is sprayed, only an effect that is not significantly different from that of normal showering is obtained, and it is difficult to uniformly wet the adhesive layer on the lamina surface. Therefore, the Sauter average particle diameter d32 of the water mist was set to 5 to 100 μm. The Sauter average particle diameter d32 can be easily measured by, for example, a particle size distribution measuring apparatus using a laser diffraction principle.

  The structure of the spraying device used in the present invention is not necessarily a special structure, but the Sauter average particle diameter d32 of the water mist to be sprayed can be adjusted in the range of at least 5 to 100 μm, and the spray amount of the water mist can be adjusted. It must be adjustable over a wide range. Further, it is preferable that both the air supply pipe and the water supply pipe are provided with a flow rate adjusting valve and / or a pressure reducing valve so that the spraying rate can be adjusted, and the spray pattern can be adjusted.

  Furthermore, it is preferable to manufacture a laminated material made of lamina having different dimensions by adopting an attachment structure in which the spray position, spray direction, and spray angle can be freely adjusted.

  As the spraying device and its mounting position, the distance from the nozzle tip to the adhesive layer surface on the lamina is 30 to 100 cm, the air pressure of the spraying device is 0.6 MPa, and 0.05 to 0.5 MPa by the pressure reducing valve The water pressure can be adjusted within a range of 0.1 to 0.5 MPa. It is preferable that at least one nozzle is attached so that the nozzle can be sprayed on the lamina surface.

  Next, the lamination process will be described with reference to FIG. The water-based adhesive is applied, and the surface where the water-based adhesive 102 is applied and the surface where the water-based adhesive 102 is not applied are stacked on each of the laminas sprayed with water mist. Lamina which does not apply the water-based adhesive 102 is used for the uppermost surface. The number of deposits can be from 2 to around 100 depending on the thickness of the lamina to be pressed and the capability of the pressing machine 401. After the adhesive application and water mist spraying steps, the above lamination step is performed, and then the pressing step is entered.

  After the water-based adhesive application and water mist spraying processes, the deposition is started until the water-based adhesive application surface and the non-coated surface are overlapped, and the deposition starts from the stacking process to the pressing process. . Here, under normal conditions, the open deposition time is 10 to 60 seconds and the closed deposition time is 5 to 10 minutes.

  The working environment of the open deposition and laminating process is 3 to 5 ° C. lower than the normal working environment, and the relative humidity is increased by 10 to 20% by water mist spraying. Thereafter, the process from the stacking process to the pressing process is under a normal atmosphere.

  When water mist is sprayed, the surface of the water-based adhesive 102 is wetted, and the ambient temperature and the relative humidity in the laminating and laminating processes after the application of the adhesive are appropriately controlled. It is considered that an open deposition time and a closed deposition time that are the same as in winter can be obtained.

  Next, the pressing process will be described with reference to FIG. A plurality of laminated laminae after the laminating process are installed in a pressing machine 401 and pressed in a range of 0.8 to 1.2 MPa and 20 to 40 minutes to form a laminated material 402. After pressing, it is left for 3 to 6 days in an atmosphere of 30 to 40 ° C. and cured.

  Next, examples of the present invention will be described in detail together with comparative examples and reference examples. In the embodiment, the atmospheric temperature in summer is 30 to 40 ° C., and a water-based adhesive having a non-volatile component concentration of 50 to 80% used in winter is applied to lamina and sprayed with water mist to perform open deposition and closed deposition for a predetermined time. Further, a pressing process was performed. The obtained laminated lumber specimen was subjected to a boiling peeling test. Specifically, based on the above embodiment, the non-volatile component concentration of the water-based adhesive, the Sauter average particle size and spray amount of the water mist, and the closed deposition time are set, and the JAS laminated material is boiled off at the set parameters. According to the test, the peel rate at the both ends of the test piece is 5% or less, and the total peel length of the same adhesive layer is less than one quarter of each length (in the table) Other than that, it was judged as “failed” (represented by “x” in the table).

<Example 1>
The test environment before spraying with water mist was a temperature of 35 ° C., a relative humidity of 60% RH, five white woods of 300 cm × 11.0 cm × 2.2 cm as lamina, and an aqueous polymer isocyanate adhesive ( Koyo Sangyo Co., Ltd., KR-134, nonvolatile component concentration 60%) 100 parts by mass of polymeric MDI (manufactured by Koyo Sangyo Co., Ltd., AX-200) 15 parts by weight, Sauter average particle size of water mist 30 μm, A laminated material was produced under the conditions of spraying amount 10 g / m ² , closed atmosphere temperature 35 ° C., pressing pressure 1.0 MPa, 30 minutes, and curing in an atmosphere of 30 ° C. for 3 days. went. At the time of preparing the laminated wood, two water mist spraying devices, the distance from the nozzle tip to the surface of the adhesive layer on the lamina is 50 cm, the air pressure of the spraying device is 0.2 MPa, the water pressure is 0.2 MPa, and the long lamina moves The time was 60 m / min. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 75% RH.

<Example 2>
A laminated material was produced in the same manner as in Example 1 except that the non-volatile component concentration of the aqueous adhesive was 80% by mass. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 75% RH.

<Example 3>
A laminated material was produced in the same manner as in Example 1 except that the non-volatile component concentration of the aqueous adhesive was 50% by mass. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 75% RH.

<Example 4>
A laminated material was produced in the same manner as in Example 1 except that the spray amount of water mist was 20 g / m ² . The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 78% RH.

<Example 5>
A laminated material was produced in the same manner as in Example 1 except that the amount of water mist sprayed was 2 g / m ² . The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 72% RH.

<Example 6>
A laminated material was produced in the same manner as in Example 1 except that the Sauter average particle size of the water mist was 100 μm. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 72% RH.

<Example 7>
A laminated material was prepared in the same manner as in Example 1 except that the Sauter average particle size of the water mist was changed to 5 μm. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 78% RH.

<Comparative Example 1>
A laminated material was produced in the same manner as in Example 1 except that the non-volatile component concentration of the water-based adhesive was 85% by mass. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 75% RH.

<Comparative example 2>
A laminated material was produced in the same manner as in Example 1 except that the amount of water mist sprayed was 30 g / m ² . The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 82% RH.

<Comparative Example 3>
A laminated material was produced in the same manner as in Example 1 except that the spray amount of water mist was changed to 0 g / m ² . The temperature of the atmosphere during open deposition was 35 ° C. and the relative humidity was 60% RH.

<Comparative example 4>
A laminated material was produced in the same manner as in Example 1 except that the Sauter average particle size of the water mist was 120 μm. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 75% RH.

<Comparative Example 5>
A laminated material was produced in the same manner as in Example 1 except that the Sauter average particle size of the water mist was 2 μm. The temperature of the atmosphere during open deposition was 31 ° C. and the relative humidity was 78% RH.

<Reference Example 1>
The laminated material was prepared in the same manner as in Example 1 except that the temperature of the atmosphere before spraying the water mist and the temperature of the atmosphere of the closed deposition was 15 ° C., the relative humidity was 45% RH, and the spray amount of the water mist was 0 g / m ^2. Produced.

<Reference Example 2>
A laminated material was produced in the same manner as in Example 1 except that the non-volatile component concentration of the water-based adhesive was 40% by mass and the spray amount of water mist was 0 g / m ² .

<Test results>
Table 1 shows the results of the boiling peeling test of the laminated wood produced under the above conditions.

  In Examples 1 to 7 and Comparative Examples 1, 2, 4, and 5, spraying water mist decreased the temperature and increased the relative humidity. However, in Comparative Example 1, the concentration of the non-volatile component of the water-based adhesive was too high, so that the case where the closed deposition time was 10 minutes or more was rejected even though the water mist was sprayed. In Comparative Example 2, since the amount of water mist sprayed was too large, the moisture content of the adhesive increased, resulting in poor adhesion. In Comparative Example 3, water mist was not sprayed, so the adhesive was dried and the deposition time was 10 minutes or more. In Comparative Example 4, since the Sauter average particle size of the water mist is too large, the adhesive layer cannot be uniformly wetted. In Comparative Example 5, the Sauter average particle size of the water mist is too small, so the water mist itself Was scattered over a wide area, the amount of water sprayed on the adhesive layer was reduced, and the adhesive layer was not sufficiently wetted.

  On the other hand, in Examples 1-7, the test environment was set to the working environment other than the summer, the reference example 1 and the test environment were set to the summer working environment, the non-volatile component concentration of 40% by mass was applied, and the water mist was applied. The same performance as in Reference Example 2 in the case of no spraying could be obtained. This is because the surface of the applied water-based adhesive is moistened by water mist, and the environmental temperature and relative humidity around the lamina after the adhesive is applied are controlled appropriately. It is considered that the open deposition time and the closed deposition time which are not changed can be obtained.

  According to the method for producing a laminated lumber of the present invention, even in a high-temperature work environment such as summer, the adhesive surface is wetted by spraying water mist immediately after application of the aqueous adhesive, and at the same time after application of the adhesive. Since the ambient temperature and the relative humidity in the lamina and in the laminating process are appropriately controlled, the adhesion failure phenomenon due to the drying of the adhesive can be avoided.

DESCRIPTION OF SYMBOLS 100 Roll coater 101 Lamina 102 Water-based adhesive 103 Roll 201 Injection nozzle 401 Pressing machine 402 Glue

Claims (2)

In the manufacturing method of the laminated material formed by laminating and laminating a plurality of laminas,
After applying a water-based adhesive having a non-volatile component concentration of 50 to 80% by mass to each laminating surface of the lamina to form a water-based adhesive coating surface, water mist is immediately added at a rate of ² to 20 g / m ^2. A method for producing a laminated material, wherein the laminar adhesive surfaces are put together, closed and deposited, and then pressed at room temperature after spraying on the application surface of the water-based adhesive and depositing it open.   The method for producing a laminated material according to claim 1, wherein the water mist has a Sauter average particle diameter d32 of 5 to 100 µm.

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