JP2012056318A - Hard polyurethane foam producing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hard polyurethane foam producing apparatus for producing hard polyurethane foam having high dispersivity in which glass fibers are uniformly dispersed in a polyurethane molding.SOLUTION: In the hard polyurethane foam producing apparatus including: a driven roll around which a strand mat comprising a continuous strand is wound; a driving device for feeding the strand mat wound around the driven roll to the downstream side; a fibrillation device for passing the strand mat fed from the driven roll therethrough while compressing it; and an application device applying an undiluted solution of the hard polyurethane foam to the strand mat fed from the fibrillation device, the hard polyurethane foam producing apparatus includes a tension application device for applying tension of 0.15 to 0.95 times the maximum allowable tension of the strand mat to the strand mat passing through the fibrillation device by braking the rotation of the driven roll. The hard polyurethane foam producing apparatus produces the hard polyurethane foam in which the dispersivity of the glass fibers constituting the strand mat is ≥85%.

Description

  The present invention relates to an apparatus for producing rigid polyurethane foam.

  Rigid polyurethane foam is mainly used as a heat insulating material, and there is a marine cold insulation material mainly used for transporting liquefied gas such as LNG. Because this marine cold insulation material is exposed to a wide temperature range from room temperature to an ultra-low temperature of about -160 ° C, even if such a temperature change occurs, cracking due to material distortion does not occur, and tensile strength even at an ultra-low temperature A high one is required. As an example, a rigid polyurethane foam is known in which glass fibers are dispersed in a rigid polyurethane foam to improve the strength at low temperatures.

  Conventionally, as a method for producing such a rigid polyurethane foam, from the viewpoint of efficient continuous operation, a relatively thin 3 to 10 continuous strand mat (CSM) is continuously supplied, The foamable resin undiluted solution is applied to the strand mat laminate while being transported, and the foamable resin undiluted solution is impregnated with the strand mat. After a certain period of time, the foamable resin undiluted solution is foamed and molded. The method is taken.

The strand mat is formed by matting glass fibers having a diameter of several μm to several tens of μm with an adhesive and having a thickness of about 1 to 5 mm. Since the strand mat is impregnated with the foamable resin stock solution, and then the foamed product has a stronger bonding force between the glass fibers than the strength that expands the glass fibers constituting the strand mat, the polyurethane foam only Will swell to the outside of the mat. That is, as shown in FIG. 8, the foam molded article is a structure in which polyurethane foam layers v _{0 to} v ₇ without glass fibers and polyurethane foam layers m _{1 to} m ₇ with glass fibers alternately laminated. In general, the total height of the polyurethane foam layers m _{1 to} m _{7 in which} the glass fibers are present is about 50% of the height h of the foamed molded product (hereinafter, this ratio is also referred to as “dispersion degree”). As a matter of fact, the mechanical strength is partially inferior, and thus when this is used as a marine cold insulation material, problems such as shrinkage and cracking in an ultra-low temperature state occur.

As a solution to this problem, Japanese Patent Application Laid-Open No. 2003-80536 discloses that a plurality of strand mats are supplied from the first roll before each strand mat is formed by continuously supplying the strand mats. A method for increasing the bulk that is allowed to pass while being compressed by a single pressure roll is disclosed. According to this method, since the adhesive is broken by the crimping roll, the bonding strength between the glass fibers is weakened, the bulk of the strand mat is increased, and the glass fibers are easily expanded when the polyurethane stock solution is foamed. The degree of dispersion of the glass fiber is increased and the mechanical strength is improved.
JP 2003-80536 A (Claims 1, 2 and 4)

  However, even when the strand mat bulk increasing device disclosed in Japanese Patent Application Laid-Open No. 2003-80536 is used, the degree of dispersion is about 50 to 70% without sufficiently weakening the bonding force between the glass fibers. When this was used as a marine cold insulation material, the problem of cracks associated with expansion and contraction was not solved and was not satisfactory. Accordingly, there has been a demand for development of a rigid polyurethane foam having almost no polyurethane foam layer free from glass fibers in the entire foamed laminate, that is, having a high degree of dispersion.

  Accordingly, an object of the present invention is to provide an apparatus for producing a rigid polyurethane foam for producing a rigid polyurethane foam having a high degree of dispersion of glass fibers, which has almost no polyurethane foam layer free of glass fibers.

  In this situation, as a result of intensive studies, the present inventors have (1) sent out the strand mat wound around the driven roll, and defibrated while compressing the fed-out strand mat by the defibrating means. In the method, conventionally, the defibration has been performed in a state in which the mat is not substantially tensioned or controlled, and (2) the strand that brakes the rotation of the driven roll and passes through the defibrating means. When a predetermined tension is applied to the mat, it has been found that the defibrating effect becomes remarkable and the dispersity of the glass fibers in the hard polyurethane foam molded body after foaming is 85% or more, and the present invention has been completed. .

  That is, the present invention is a driven roll around which a strand mat made of continuous strand is wound, a driving means for feeding the strand mat wound around the driven roll downstream, and the driven roll fed from the driven roll An apparatus for producing a rigid polyurethane foam, comprising: a defibrating means for allowing the strand mat to pass while being compressed; and a coating device for applying a stock solution of the rigid polyurethane foam to the strand mat fed from the defibrating means. Dispersion of the glass fibers constituting the strand mat, comprising tension applying means for applying a tension of 0.15 to 0.95 times the maximum allowable tension of the strand mat to the strand mat passing through the defibrating means by braking the rotation A device that produces rigid polyurethane foam with a degree of 85% or more. There is provided an apparatus for producing rigid polyurethane foams, characterized in.

  According to the apparatus for producing a rigid polyurethane foam of the present invention, the defibrating efficiency is improved only by installing a tension applying means in an existing apparatus. Further, if the tension applying means is a method of applying a brake to the roll shaft of the driven roll or the side plate integrated with the roll shaft, it is only necessary to install a simple brake means, and an increase in cost can be suppressed. Also, a method of braking the rotation of the driven roll by a frictional resistance between the roll surface and the braking material by bringing a braking material into contact with the roll surface of the strand mat wound around the driven roll, or of the strand mat drawn from the driven roll With the method of sandwiching both surfaces with a braking material, a constant tension such as ± 20% of the target tension can be applied to the roll between the driven roll and the drive roll during continuous operation. The obtained strand mat can be obtained continuously and stably. Moreover, if the polyurethane foam production apparatus of the present invention is used, a rigid polyurethane foam having a dispersity of 85% or more can be obtained, and there is no change in tensile strength at room temperature and low temperature. For example, it can be used as a cold insulation material for ships. The problem of cracks associated with expansion and contraction does not occur.

BRIEF DESCRIPTION OF THE DRAWINGS The simplification figure of the polyurethane foam manufacturing apparatus which shows the embodiment. The simplified view which looked at the defibrating means used with the polyurethane foam manufacturing apparatus of this example from the top. The side view of the defibrating means of FIG. The simplified view which looked at the drive means used with the polyurethane foam manufacturing apparatus of this example from the top. The side view of the drive means of FIG. The simplified view which looked at the tension | tensile_strength provision means used with the polyurethane foam manufacturing apparatus of this example from the front. The simplification figure of the cross-section of the mat laminated body conveyed to a polyurethane stock solution immersion process. FIG. 8 is a simplified diagram of a cross-sectional structure after foaming the mat laminate of FIG. 7 with a urethane stock solution. The simplification figure of the apparatus which measures the tension | tensile_strength of the mat | matte in the manufacturing apparatus of this example. The simplified diagram explaining the other tension | tensile_strength provision means which looked at the driven roll from the front. The simplified view explaining the other tension | tensile_strength provision means which looked at the driven roll from the side. The simplified view explaining the other tension | tensile_strength provision means which looked at the driven roll from the side. The simplified view explaining the other tension | tensile_strength provision means which looked at the driven roll from the side. The simplified view which looked at the other defibrating means used with the polyurethane foam manufacturing apparatus of this example from the top. The figure which showed the result of the confirmation experiment of fixed tension maintenance in a reference example.

Next, an apparatus for producing a rigid polyurethane foam (hereinafter also simply referred to as “polyurethane foam”) in an embodiment of the present invention, a method for producing a rigid polyurethane foam using the apparatus, and a rigid polyurethane obtained by the production apparatus The form will be described with reference to FIGS.
An apparatus for producing a rigid polyurethane foam according to the present invention includes a driven roll around which a strand mat is wound, drive means for feeding the strand mat wound around the driven roll downstream, and a strand fed from the driven roll. An apparatus for producing a rigid polyurethane foam, comprising: a defibrating means for allowing the mat to pass while being compressed; and a coating apparatus for applying a stock solution of the rigid polyurethane foam to the strand mat sent from the defibrating means, the driven roll Is provided with tension applying means for applying a predetermined tension to the strand mat passing through the defibrating means by braking the rotation of the fiber.
FIG. 1 is a simplified view of a polyurethane foam manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is a top view of defibrating means used in the polyurethane foam manufacturing apparatus of FIG. 1, and FIG. 3 is a right side view of FIG. 4 is a top view of the defibrating means used in the polyurethane foam manufacturing apparatus of FIG. 1, FIG. 5 is a right side view of FIG. 4, and FIG. 6 is a tension applying means used in the polyurethane foam manufacturing apparatus of FIG. FIG. 7 is a simplified diagram of the cross-sectional structure of a strand mat (hereinafter also simply referred to as “mat”) laminate conveyed from the defibrating means to the polyurethane foam stock solution dipping process of the next process, and FIG. FIG. 9 is a simplified view of the cross-sectional structure of the mat laminate after foaming the polyurethane foam stock solution, and FIG. 9 is a simplified view of an apparatus for measuring the tension of the mat. The mat is made of glass fiber.

  The polyurethane foam manufacturing apparatus 20 includes, for example, an apparatus group in which a plurality of mat feeding apparatuses 10a and 10b including a driven roll 1, a driving means 3, a defibrating means 4 and a tension applying means 5 as shown in FIG. A conveying means 40 for laminating and conveying the defibrated mats 9a and 9b sent out from the group, and a coating device 70 for applying a foamed resin stock solution to the mat laminate 30 on the conveying means 40 are provided. The mat feeding devices 10a and 10b include a driven roll 1 around which the mat 2 is wound up, a driving means 3 for feeding the mat 2 wound up around the driven roll 1 downstream (downward in FIG. 1), and a driven A defibrating roll 4 that is positioned between the roll 1 and the driving means 3 and passes through the mat 2 fed from the driven roll 1 while being compressed, and a mat 2 that passes through the defibrating roll 4 by braking the rotation of the driven roll 1. And a tension applying means 5 for applying a predetermined tension. In FIG. 1, the roll between the driving means 3 and the defibrating roll 4 may be either the driving means 3 or the defibrating roll 4. Further, the defibrating roll 4 may function as the driving means 3 by giving a driving force.

  In the mat feeding devices 10a and 10b, the driven roll 1 is obtained by winding a mat 2 for polyurethane foam around a driven roll shaft 11, and rotates in a clockwise direction when viewed from the right side in FIG. 2 is sent out downward. Since the driven roll shaft 11 is rotatably supported, when the mat 2 is unwound by the driving means 3, there is no great frictional resistance and the driven roll 1 rotates very smoothly.

  The mat 2 for producing the polyurethane foam is not particularly limited, and is a glass fiber having a diameter of several μm to several tens of μm bonded by an adhesive such as polyester, and has a thickness of about 1 to 5 mm and a length. Is in the form of a sheet of several tens to several hundreds of meters. Specific examples of the glass fiber include fibers such as chop strands and continuous strands. Among these, glass fiber mats produced using continuous strands are preferred in that they are excellent in impregnation properties of foamable resin stock solutions and foam reinforcement properties. Although the usage-amount of an adhesive agent is not restrict | limited in particular, For example with respect to the mat | matte 2, it is 1.0 to 5.0 weight% by an externally divided weight. If the amount of the adhesive used is too small, the bonding between the glass fibers becomes insufficient and the mat shape cannot be maintained. If too much, the bonding force between the glass fibers increases and the polyurethane stock solution foams. However, the degree of dispersion of the glass fibers in the polyurethane molded product is lowered.

  The drive means 3 sends out the mat 2 wound up by the driven roll 1 to the downstream side. The driving means 3 is not particularly limited, and includes a pair of rolls having a driving force, a pair of belt conveyors having a driving force, and the like. The pair of belt conveyors having a driving force sandwich the mat between the belts and send the mat to the downstream side. As shown in FIGS. 4 and 5, the driving means 3 of this example is a pair of gear-shaped cross-section rolls facing each other, and is rotated by driving means such as a motor attached to one or both roll shafts. The mat 2 is sandwiched between the pair of rolls from both sides and pulled out from the driven roll 1 by screwing the teeth of one roll and the other roll. The drive means 3 is not limited to a roll having a gear-like cross section as shown in FIGS. 4 and 5, and may be a pair of rolls in which an elastic body such as rubber is provided on the outer layer portion.

  In the state where the tension applying means 5 described later is not acting, the mat 2 is sent out in a state where there is substantially no tension in the mat 2 between the driving means 3 and the driven roll 1 during the continuous operation. Moreover, the description of the mat 2 is omitted in FIG.

  The defibrating roll 4 is located between the driven roll 1 and the driving means 3. The defibrating roll 4 is not particularly limited as long as it allows the mat 2 sent from the driven roll 1 to pass through it while compressing it from both sides, but as shown in FIGS. A plurality of disk-like protrusions 43 having a trapezoidal tooth profile are arranged at a predetermined pitch in the axial direction of the shaft 44, and the disk-like protrusions 43 of the rolls 4 a and 4 b arranged on the respective shafts 44 are not opposed to each other in the axial direction. Arranged at a shifted position. At the time of defibration, the pair of defibrating rolls 4 are brought close to each other until the disc-shaped protrusion 43 and the peripheral surface 42 of the shaft are in contact with each other or almost in contact with each other. The defibrating roll 4 may be a rotating roll that is rotatably supported, or a driving roll that interlocks the roll shaft and the motor. Moreover, the rotation direction of a pair of defibration roll 4 which opposes is a mutually reverse direction normally. Moreover, in FIG. 1, the defibrating roll 4 has two upper and lower stages, but is not limited to this, and may have one, three, or more stages. According to such a defibrating roll 4, the mat 2 passed between them receives a strong pressure from both sides and deforms into a corrugated shape, and a predetermined tension is applied in the longitudinal direction of the mat 2. A shearing force works in the length direction, fiber bonding by the adhesive added to the mat 2 can be effectively broken, and a high defibrating effect can be obtained.

  The defibration roll is not limited to the shape provided with the disk-shaped protrusion 43 as shown in FIGS. 2 and 3, and is a disk-shaped protrusion 43a having a rounded peripheral surface as shown in FIG. Also good. Further, the defibrating roll 4 may function as the driving means 3 by giving a driving force.

  In this invention, a tension | tensile_strength provision means will not be restrict | limited especially if a predetermined | prescribed tension | tensile_strength is provided to the mat | matte which suppresses rotation of a driven roll and passes a defibration roll. The tension applying means 5 shown in FIGS. 1 and 6 is a means for holding the roll shaft 11 of the driven roll 1 with a brake pad 67 to brake the rotation of the driven roll 1 (hereinafter also referred to as tension pad means). That is, the tension pad means has a clamping force adjusting means that adjusts the clamping force according to a change in the rotational speed by a clamping force applying device (not shown). As a form of the brake pad 67, a pressing method can be adopted in addition to a clamping method.

  The predetermined tension is preferably 0.15 to 0.95 times, preferably 0.3 to 0.85 times the maximum allowable tension of the mat 2, in view of increasing the defibrating effect by the defibrating roll 4. When the tension is less than 0.15 times the maximum allowable tension of the mat 2, the defibrating effect by the defibrating roll 4 is low, and the degree of dispersion of the glass fibers in the polyurethane molded body is only about 50 to 70%. In addition, when the tension exceeds 0.95 times the maximum allowable tension of the mat 2, there is a problem that the mat 2 is excessively stretched or torn. Further, the predetermined tension is within the above range, and the tension is maintained at ± 20% of the target tension value, so that a constant tension can be applied to the mat 2 during the operation of the apparatus. It is preferable at the point from which a polyurethane molded object is obtained.

  A method of measuring the maximum allowable tension of the mat 2 will be described with reference to FIG. FIG. 9 uses the polyurethane foam manufacturing apparatus 10 of FIG. 1 and bypasses it without using the associated roll member. The leading end of the mat 2 drawn out from the driven roll 1 is wound around and fixed to the paper tube 56, the spring 57 is attached to the paper tube 56, and the string portion 58 of the spring 57 is connected to the belt via the guide roll 59. It is attached to the conveyor 40. In this state, the belt conveyor 40 is operated at the conveyance speed at the time of actual manufacture, the tension is adjusted by the tension applying means, the tensile load immediately before the mat 2 is torn is measured, and this value is determined as the maximum allowable value of the mat 2. It is to be tension.

  The maximum allowable tension of the mat 2 is preferably performed every time the mat 2 to be used is changed from the viewpoint of obtaining a stable and high defibrating effect. For example, a mat having the same production batch or an approximate mat characteristic is used. In the case where the accumulated data for each mat has a certain tendency or the like, it can be determined in consideration of the result and the accumulated data which have been carried out previously. As described above, the maximum allowable tension of the mat refers to a maximum tension that does not cause problems such as tearing of the mat when tension is applied to the mat. The maximum allowable tension of the mat is approximately 50 to 200 N / m, although it cannot be generally determined depending on the purpose and characteristics of the mat.

  When a plurality of mat feeding devices used in the polyurethane foam manufacturing apparatus 20 of the present invention are arranged, it is preferable to provide tension applying means in each mat feeding device. In addition, a coating apparatus for applying a polyurethane foam stock solution to the strand mat sent from the defibrating means used in the polyurethane foam production apparatus 20 of the present invention is not particularly limited, and known apparatuses can be used.

  The polyurethane foam manufacturing method carried out by using the polyurethane foam manufacturing apparatus according to the present invention is to send the strand mat wound around the driven roll 1 to the downstream side by the driving means 3, and the fed strand mat. In a method for producing a polyurethane foam, which is defibrated while being compressed by a defibrating means, and a polyurethane foam undiluted solution is applied to the defibrated strand mat, the rotation of the driven roll is braked and the defibrated means passes. A predetermined tension is applied to the strand mat.

  In the polyurethane foam manufacturing apparatus 20 of FIG. 1, the defibrating roll 4 has a gap formed by separating a pair of rolls. One end of the mat 2 wound around the driven roll 1 is passed between the pair of defibrating rolls 4 and the driving means 3, and the tip thereof is disposed on the belt conveyor 40. Thereafter, the distance between the shafts of the pair of defibrating rolls 4 and the driving means 3 is adjusted so that the mat 2 is sandwiched. On the other hand, the brake pad 67 is pressed against the roll shaft 11 with a predetermined force so that a predetermined tension is applied to the mat 2 passing through the defibrating roll 4.

  Next, the drive means 3 is driven, and the mat 2 wound around the driven roll 1 is pulled out downstream. At this time, the tension pad means 5 causes the driven roll 1 to be braked against forward rotation. At this time, the mat 2 passed through the defibrating roll 4 between the driven roll 1 and the driving means 3 receives a predetermined tension (stretching force) in the feeding direction of the mat 2 and receives pressure from both sides of the mat 2. Deforms into a corrugated shape. Thereby, the mat | matte 2 can acquire the high fibrillation effect because the fiber bond by an adhesive agent is destroyed effectively.

  The defibrated mat 9a continuously fed from the mat feeding device 10a is placed on the belt conveyor 40 (conveying means) and moved. Next, the defibrated mat 9b continuously fed from the mat sending device 10b on the downstream side adjacent to the mat sending device 10a is placed on the deflated mat 9a and moved in two layers. The same thing is sequentially performed, the number of defibrated mats corresponding to the number of mat delivery devices installed is stacked, and the mat laminate 30 moves on the belt conveyor 40. In FIG. 1, reference numeral 73 denotes a pressing plate. FIG. 7 shows the structure of a seven-layer mat laminate 30. The number of laminated mat bodies 30 is not particularly limited, and is usually about 3 to 10 sheets. When the number of laminated sheets is increased, the thickness of the mat per sheet can be reduced, the number of winding layers around the driven roll 1 is increased, and a longer continuous operation is possible.

  While the defibrated mats 9a and 9b are transferred, a release sheet is supplied from a release sheet supply device (not shown), and the release sheet is positioned below the mat 9a forming the lowermost layer. . The foamed resin stock solution is supplied from the top of the mat laminate 30 placed on the belt conveyor 40 by the coating device 70. As a result, the foamed resin stock solution penetrates into the inside of the mat laminate 30, and the entire mat laminate 30 is immersed in the foamed resin stock solution. The release sheet located below the mat 9a prevents the foamed resin stock solution from coming into contact with the belt conveyor 40 or the upper surface of the substrate. When the foamed resin stock solution is foam-molded into a polyurethane foam, it is integrated with the polyurethane foam. This constitutes one surface of the polyurethane foam. The foamed resin stock solution applied to the mat laminate 30 undergoes a chemical reaction within a few tens of seconds to a few minutes and is foam-molded. Since the obtained polyurethane foam is foam-molded in a state where the foamed resin stock solution has sufficiently permeated into the defibrated mat, a high-quality product with a glass fiber, that is, a dispersity of the mat 2 of 85% or more can be obtained. It will be. The foamed resin stock solution applied from the coating device is not particularly limited, and a known polyurethane foam stock solution can be used. In addition, a foaming molding is cut | disconnected to a suitable dimension at a suitable time if desired.

The “dispersion degree” in the present invention will be described with reference to FIG. 8 shows a structure in which polyurethane foam layers v _{0 to} v ₇ without glass fibers and polyurethane foam layers m _{1 to} m ₇ with glass fibers are alternately laminated. but "polydispersity" refers to the height h of the foam molded article, it refers to the proportion of the total height of the polyurethane foam layer m ₁ ~m ₇ there are glass fibers. The degree of dispersion of the polyurethane foam obtained by the apparatus for producing polyurethane foam of the present invention is 80% or more, particularly 85% or more, and good and 98%. That is, since the glass fiber of the mat 2 is sufficiently loosened, the glass fiber expands following the foaming force of the foamed resin stock solution. For this reason, it becomes the polyurethane foam in which glass fiber exists in the whole in a foaming molding. The dispersity may be measured with a ruler after the foamed molded body is cut and cooled while it is hot. Cut surface of the foamed molded layer that contains no glass fibers are present, visual polyurethane foam layer v ₀ to v ₇ in the absence of glass fibers, and a polyurethane foam layer m ₁ ~m ₇ there are glass fibers Can be confirmed more clearly.

  In the polyurethane foam manufacturing apparatus of the present invention, the tension applying means is not limited to those shown in FIGS. 1 and 6, and the tension applying means shown in FIGS. 10 to 13 can be used. FIG. 10 is a view of the driven roll 1 as viewed from the front, and FIGS. 11 to 13 are views of the driven roll 1 as viewed from the side. 10-13, the same code | symbol is attached | subjected to the component same as FIG.1 and FIG.6, the description is abbreviate | omitted, and a different point is demonstrated. That is, FIG. 10 differs from FIGS. 1 and 6 in that the tension applying means presses the brake pad 68 against the outer surface of the side plate 111 integral with the roll shaft 11 of the driven roll 1 to brake the rotation of the driven roll 1. Is. Even such a tension applying means has the same effect as the tension applying means of FIG.

  11 differs from FIG. 1 and FIG. 6 in that the tension applying means sandwiches both surfaces of the mat 2 pulled out from the driven roll 1 by the braking material 69 positioned between the driven roll 1 and the defibrating roll 4, and brakes. A tension is applied to the mat 2 positioned between the material 69 and the driving means 3. Even such a tension applying means has the same effect as the tension applying means of FIG. The force for sandwiching the mat 2 by the braking material 69 is appropriately determined by the frictional force between the mat 2 and the braking material 69, the feed speed of the mat 2, and the like.

  12 differs from FIG. 1 and FIG. 6 in that the tension applying means brings the braking material 74 into contact with the roll surface 12 of the mat 2 wound around the driven roll 1, and the friction between the roll surface 12 and the braking material 74. The rotation of the driven roll 1 is braked by the resistance. The braking material 74 is a plate-like body, and one side of the plate-like body is rotatably fixed to the fulcrum 73, and a pressing force is applied to the roll surface 12 by the weight 75 suspended at the tip, thereby rotating the driven roll 1. Braking.

  13 differs from FIG. 1 and FIG. 6 in that the tension applying means presses the sheet-like braking material 74a against the roll surface 12 of the mat 2 wound around the driven roll 1 against the roll surface. The rotation of the driven roll 1 is braked by the frictional resistance with the material 74a. The sheet-like braking material 74 a has one side of the sheet-like object fixed to the fulcrum 73 and applies a pressing force to the roll surface 12 by the weight 75 suspended from the tip, thereby braking the rotation of the driven roll 1.

  EXAMPLES Next, although an Example is given and this invention is demonstrated more concretely, this is only an illustration and does not restrict | limit this invention.

(Reference example) (Confirmation experiment of holding constant tension in mat feeder)
Using the tension measuring device shown in FIG. 9, the change in tension applied to the mat during continuous operation was measured using the braking material 74. The measurement was performed at four points of the maximum roll diameter 510 mm, 290 mm, and 150 mm of the driven roll immediately after the start of operation and the roll diameter 110 mm immediately before the end of the operation. The result is shown in FIG. The strand mat used was U801 manufactured by Vetrotex. The maximum allowable tension of this strand mat is 100 N / m. From the results of FIG. 15, it can be seen that a substantially constant tension can be applied between the driven roll and the drive roll during continuous operation.

Example 1
Using the polyurethane foam production apparatus shown in FIG. 1, a polyurethane foam was produced under the following operating conditions. The belt conveyor 40 and the coating device 70 which are conveying devices are existing and widely known devices. The dispersion degree of the glass fiber in the obtained polyurethane foam molded product, the presence or absence of tearing of the mat 2, the tensile strength of the polyurethane foam molded product at 25 ° C, and the tensile strength of the polyurethane foam molded product at -196 ° C were measured. The results of the dispersity and the presence or absence of tearing of the mat 2 are shown in Table 1, and the results of the tensile strength of the polyurethane foam molded body at 25 ° C. and the tensile strength of the polyurethane foam molded body at −196 ° C. are shown in Table 2. The strand mat was the same as that used in the reference example, and an aramid fiber brake pad was used as the tension applying means.

(Foamed resin stock solution)
A solution R is prepared by stirring and mixing 20% by weight of polyol A, 20% by weight of polyol B, 60% by weight of polyol C, 1.3% by weight of water, 2% by weight of foam stabilizer, 0.3% by weight of catalyst and 14% by weight of flame retardant. Then, the R solution and the I solution were mixed at a NCO / OH equivalent ratio of 1.15 with a high-speed stirrer at room temperature and liquid temperature of 25 ° C. to prepare a foamed resin stock solution of rigid polyurethane foam. did. In addition, the weight percent is the inner percentage of the polyol component as a whole and the other percentage is the outer percentage of the polyol component.

  Polyol A is sorbitol polyether polyol (viscosity at 25 ° C .: 2000 mPa · s, hydroxyl value: 370 mgKOH / g), and polyol B is aromatic amine polyether polyol (viscosity at 25 ° C .: 12500 mPa · s, hydroxyl value: 465 mgKOH / g), polyol C is glycerin polyether polyol (viscosity at 25 ° C .: 410 mPa · s, hydroxyl value: 415 mg KOH / g), polyisocyanate is polymeric MDI isocyanate (polymethylene polyphenyl polyisocyanate) (NCO content: 31) 0.0%, viscosity at 25 ° C .: 180 mPa · s), the foam stabilizer is a silicone surfactant, the flame retardant is trischloropropyl phosphate, and the catalyst is an imidazole amine catalyst.

(Tensile strength)
Five samples were collected from the central part in the thickness direction of the rigid polyurethane foam. The tensile strength of the foamed molded product at 23 ° C. and −196 ° C. (in liquid nitrogen) was measured by a measurement method based on ISO 1926. The tensile direction of the tensile test was the vertical direction of the foam molded body in the height direction (foaming direction), that is, the width direction of the mat.

(Examples 2 to 4 and Comparative Example 1)
The conditions shown in Table 1, ie, 50 N / m (Example 2), 80 N / m (Example 3), 95 N / m (Example 4) instead of the tension of 20 N / m applied to the mat by the tension applying means, and The same method as in Example 1 was performed except that 0 N / m (Comparative Example 1) was used. The results are shown in Tables 1 and 2. Note that 0 N / m in Comparative Example 1 is obtained by omitting the installation of the tension applying means.

(Example 5)
A strand mat having a maximum allowable tension of 60 N / m was used in place of the strand mat having a maximum allowable tension of 100 N / m, and that a tension of 20 N / m applied to the mat by the tension applying means was changed to 12 N / m. The same method as in Example 1 was performed. The results of the dispersity and the presence or absence of tearing of the mat are shown in Table 3, and the results of the tensile strength at 25 ° C. and the tensile strength at −196 ° C. are shown in Table 4.

(Examples 6 to 8 and Comparative Example 2)
The conditions shown in Table 3, that is, instead of the tension of 12 N / m applied to the mat by the tension applying means, 30 N / m (Example 6), 48 N / m (Example 7), 57 N / m (Example 8) and The same method as in Example 5 was performed except that 0 N / m (Comparative Example 2) was used. The results are shown in Tables 3 and 4. Note that 0 N / m in Comparative Example 2 is obtained by omitting the installation of the tension applying means.

  From the results of Tables 1 to 4, all of the polyurethane foams of the examples have high dispersibility, and the dispersibility of the mat in the foamed molded product is extremely high. For this reason, even if this is used for a marine cooler, the tensile strength is large and the variation is small at both normal temperature and extremely low temperature as compared with the comparative example.

1 Follower roll 2 Glass fiber mat (mat)
DESCRIPTION OF SYMBOLS 3 Drive means 4 Disentanglement roll 5, 5a, 5b Tension providing means 9a, 9b Disentangled mat 10a, 10b Mat delivery apparatus 11 Roll shaft 20 Polyurethane foam manufacturing apparatus 30 Mat laminated body 40 Belt conveyor 50 Foam molding (polyurethane) Form)
67 Brake pads

Claims (5)

A driven roll on which a strand mat made of continuous strand is wound, driving means for feeding the strand mat wound on the driven roll to the downstream side, while compressing the strand mat fed from the driven roll In an apparatus for producing a rigid polyurethane foam, comprising: a defibrating means to be passed; and a coating apparatus for applying a stock solution of the rigid polyurethane foam to a strand mat sent from the defibrating means.
Comprising tension applying means for braking the rotation of the driven roll and applying a tension of 0.15 to 0.95 times the maximum allowable tension of the strand mat to the strand mat passing through the defibrating means;
An apparatus for producing a rigid polyurethane foam, which is an apparatus for producing a rigid polyurethane foam having a dispersion degree of glass fibers constituting the strand mat of 85% or more.   The apparatus for producing a rigid polyurethane foam according to claim 1, wherein the tension applying means presses a brake pad against a roll shaft of the driven roll to brake the rotation of the driven roll.   The tension applying means abuts a braking material on a roll surface of a strand mat wound around a driven roll, and brakes rotation of the driven roll by frictional resistance between the roll surface and the braking material. The manufacturing apparatus of the rigid polyurethane foam of Claim 1.   The apparatus for producing a rigid polyurethane foam according to claim 1, wherein the tension applying means presses a braking material against a side plate surface integrated with a roll shaft of the driven roll to brake the rotation of the driven roll.   The apparatus for producing a rigid polyurethane foam according to claim 1, wherein the tension applying means sandwiches both sides of the strand mat drawn from the driven roll with a braking material to brake the rotation of the driven roll.

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