Abstract:
In order to obtain a glove, a hand mold is first dipped into a transparent rubber latex composition to form a coat layer. Next, the hand mold is dipped into a fluid including an ink floated and nonuniformly dispersed on the surface of the fluid. Upon dipping, the ink is transferred to the surface of the coat layer, whereby forming a decorative layer. Next, this hand mold is dipped into another rubber latex composition to form a base layer. Next, the coat layer and the base layer are heated. Heating causes a crosslinking reaction of the rubber to yield a glove. The glove is removed from the hand mold. Upon mold removal, the glove  2  is turned inside out, thereby allowing the coat layer to appear on the obverse face. Because the coat layer is transparent, the decorative layer can be observed from outside. The decorative layer provides the glove with a marble pattern.

Description:
[0001]     The present application is a 37 C.F.R. §1.53(b) divisional of U.S. application Ser. No. 11/110,762 filed Apr. 21, 2005, which in turn claims priority on Japanese Application No. 2004-289908 filed Oct. 1, 2004. The entire contents of each of these applications are hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a method of manufacturing gloves. More particularly, the present invention relates to a process for forming a pattern of gloves.  
         [0004]     2. Description of the Related Art  
         [0005]     At general home and restaurants, rubber gloves have been utilized. General rubber gloves have been manufactured by a coagulant method. In the coagulant method, a hand mold, which is called “former”, is first dipped into a coagulant, and then picked up. This dipping results in adherence of the coagulant to the surface of the hand mold. Next, the hand mold is dipped into a rubber latex composition, and is then picked up. This dipping results in adherence of the rubber latex composition to the surface of the hand mold. By drying this rubber latex composition, a coated film is formed on the surface of the hand mold. Upon heating of this coated film and the hand mold, a crosslinking agent included in the coated film causes a chemical reaction to allow the rubber to be crosslinked. According to this crosslinkage, gloves are obtained. Naps may be planted prior to the crosslinking as needed.  
         [0006]     A colorant is blended in the rubber latex composition. The colorant is uniformly dispersed in the composition. The main body is colorized by this colorant. Depending on the type and amount of the colorant, gloves exhibiting a variety of colors are obtained. Such a coagulant method is disclosed in JP-A No. 2002-327324.  
         [0007]     There are many applications of rubber gloves. For example, at general home, rubber gloves have been used for cooking foods and drinks, washing dishes, disposing raw garbage, laundry operations, cleaning and the like. From a hygienic point of view, it is not preferred to use rubber gloves upon cooking which had been used upon cleaning. It is necessary to provide and use multiple rubber gloves separately, depending on the application. When a lot of rubber gloves are provided, application of each rubber gloves must be discriminated. This discrimination is carried out based on the color. For example, pink rubber gloves are used in cooking, while blue rubber gloves are used in cleaning.  
         [0008]     As described above, colorization of a rubber glove is executed by a colorant uniformly dispersed in a rubber latex composition, therefore, the rubber glove exhibits single color. Because variations of appearance of rubber gloves are not so wide, discrimination of applications based on the color can not be sufficiently performed. Rubber gloves exhibiting single color are not preferred in respect of their design.  
         [0009]     An object of the present invention is to provide a manufacturing method which enables to yield gloves exhibiting a variety of appearances. Another object of the present invention is to provide gloves which are excellent in their design.  
       SUMMARY OF THE INVENTION  
       [0010]     The method of manufacturing a grove according to the present invention comprises:  
         [0011]     (1) a first step of dipping a hand mold into a transparent latex composition to form a coat layer,  
         [0012]     (2) a second step of forming a decorative layer on the surface of this coat layer, and  
         [0013]     (3) a third step of forming a base layer through dipping this hand mold into another latex composition.  
         [0014]     Preferably, in the second step, the hand mold is dipped into a fluid including an ink floated and nonuniformly dispersed on the surface thereof, and the decorative layer is formed by transfer of this ink to the surface of the coat layer.  
         [0015]     The glove according to the present invention has a base layer which comprises a polymer as a base material, a coat layer which comprises a polymer as a base material and which is transparent, and a decorative layer positioned between the base layer and the coat layer. Preferably, a marble pattern is formed with the decorative layer. Preferably, the base material of the base layer and coat layer is a rubber, and a rubber ink is used in the decorative layer. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is a front view illustrating a glove according to one embodiment of the present invention;  
         [0017]      FIG. 2  is an enlarged cross sectional view illustrating a part of the glove shown in  FIG. 1 ;  
         [0018]      FIG. 3  is a plane view illustrating an apparatus for manufacturing the glove shown in  FIG. 1 ;  
         [0019]      FIG. 4  is a longitudinal sectional view illustrating the apparatus shown in  FIG. 3 ; and  
         [0020]      FIG. 5  is a flow chart illustrating one example of a method of manufacturing the glove shown in  FIG. 1 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     Hereinafter, the present invention is explained in detail on the basis of preferred embodiments with an appropriate reference to the drawing.  
         [0022]     The glove  2  shown in  FIG. 1  has a marble pattern. The marble pattern means a pattern generated by ununiform dispersion of a colorant. The marble pattern is also referred to as a multicolor pattern. Preferably, the marble pattern is obtained by marbling. In the marble pattern obtained by marbling, curved lines are principally found. The marble pattern attracts the preference of the people who has a look at the glove. This glove  2  has an excellent appearance.  
         [0023]     Although  FIG. 1  shows the side of the palm of the glove  2 , similar marble pattern is also formed on the back side. According to the example shown in  FIG. 1 , the marble pattern is formed on the entire face of the glove  2 , however, the marble pattern may be formed in part.  
         [0024]      FIG. 2  is an enlarged cross sectional view illustrating a part of the glove  2  shown in  FIG. 1 . In  FIG. 2 , the upper side is the obverse side of the glove  2 , while the bottom side is the reverse side of the glove  2 . This glove  2  has a base layer  4 , a decorative layer  6  and a coat layer  8 . The decorative layer  6  is laminated on the base layer  4 . The coat layer  8  is laminated on the decorative layer  6 . When the glove  2  is worn, the base layer  4  is brought into contact with the hand of the human. The glove  2  may have a naps-planted layer on the bottom side of the base layer  4 .  
         [0025]     The base layer  4  is formed by crosslinking of a rubber composition. Illustrative examples of the base rubber of the base layer  4  include natural rubbers, acrylonitrile-butadiene copolymers, styrene-butadiene copolymers, polychloroprene and acrylic rubbers. A deproteinized natural rubber may be also used. In light of strength, a natural rubber is preferred. In light of the oil resistance, an acrylonitrile-butadiene copolymer is preferred. In place of a rubber, a synthetic resin may be also used. Illustrative examples of preferred synthetic resin include acrylic resins, polyurethane and polyvinyl chloride. Two or more polymers may be used in combination.  
         [0026]     In the rubber composition for the base layer  4  is blended a crosslinking agent. Specific examples of the crosslinking agent include sulfur and organic sulfur compounds. Amount of the crosslinking agent to be blended is preferably 0.5 part by weight or greater, and more preferably 1.0 part by weight or greater per 100 parts by weight of the base rubber. The amount is preferably 5.0 parts by weight or less, and more preferably 3.5 parts by weight or less.  
         [0027]     Usually, a vulcanization accelerator is blended in the rubber composition. Illustrative examples of preferred vulcanization accelerator include zinc N-ethyl-N-phenyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, 2-mercaptobenzothiazole zinc salts and tetramethylthiram disulfide. Amount of the vulcanization accelerator to be blended is preferably 0.5 part by weight or greater and 3.0 parts by weight or less per 100 parts by weight of the base rubber.  
         [0028]     In the rubber composition may be blended a colorant (typically a pigment). Due to the colorant, the base layer  4  is colorized. Because the colorant is uniformly dispersed in the rubber composition, the base layer  4  exhibits single color.  
         [0029]     To the rubber composition may be added additives such as zinc oxide, stearic acid, an antiaging agent, a filler and the like in an appropriate amount as needed.  
         [0030]     In light of strength of the glove  2 , the base layer  4  has a thickness of 0.15 mm or greater, and particularly 0.20 mm or greater. In light of softness of the glove  2 , the base layer  4  has a thickness of 0.50 mm or less, and particularly 0.40 mm or less.  
         [0031]     The decorative layer  6  comprises a colorant. The decorative layer  6  has a ununiform thickness. By use of two or more kinds of colorants in combination in the decorative layer  6 , a marble pattern is formed. The entire face of the base layer  4  may be covered by the decorative layer  6 , alternatively, a part of the base layer  4  may be covered by the decorative layer  6 .  
         [0032]     The coat layer  8  is present on the entire face of the glove  2 . The coat layer  8  protects the decorative layer  6 . The coat layer  8  is colorless and transparent. Because the coat layer  8  is transparent, the marble pattern formed with the decorative layer  6  is recognized as an appearance of the glove  2 . The coat layer  8  may be colored and transparent.  
         [0033]     The coat layer  8  is formed by crosslinking of a rubber composition similarly to the base layer  4 . Illustrative examples of the base rubber of the coat layer  8  include natural rubbers, acrylonitrile-butadiene copolymers, styrene-butadiene copolymers, polychloroprene and acrylic rubbers. A deprotenized natural rubber may be also used. In light of the strength, a natural rubber is preferred. In light of the oil resistance, an acrylonitrile-butadiene copolymer is preferred. In place of a rubber, a synthetic resin may be also used. Illustrative examples of preferred synthetic resin include acrylic resins, polyurethane and polyvinyl chloride. Two or more polymers may be used in combination.  
         [0034]     In the rubber composition of for the coat layer  8  may be blended a crosslinking agent. Specific examples of the crosslinking agent include sulfur and organic sulfur compounds. Amount of the crosslinking agent to be blended is preferably 0.5 part by weight or greater, and more preferably 1.0 part by weight or greater per 100 parts by weight of the base rubber. The amount is preferably 5.0 parts by weight or less, and more preferably 3.5 parts by weight or less.  
         [0035]     Usually, a vulcanization accelerator is blended in the rubber composition. Illustrative examples of preferred vulcanization accelerator include zinc N-ethyl-N-phenyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, 2-mercaptobenzothiazole zinc salts and tetramethylthiram disulfide. Amount of the vulcanization accelerator to be blended is preferably 0.5 part by weight or greater and 3.0 parts by weight or less per 100 parts by weight of the base rubber.  
         [0036]     To the rubber composition may be added additives such as zinc oxide, stearic acid, an antiaging agent, a filler and the like in an appropriate amount as needed.  
         [0037]     In light of the protection of the decorative layer  6 , the coat layer  8  has a thickness of 0.10 mm or greater, and particularly 0.15 mm or greater. In light of softness of the glove  2 , the coat layer  8  has a thickness of 0.30 mm or less, and particularly 0.25 mm or less.  
         [0038]      FIG. 3  is a plane view illustrating an apparatus  10  for use in manufacturing the glove  2  shown in  FIG. 1 , and  FIG. 4  is a longitudinal sectional view of the same. This apparatus  10  has a water bath  12 , four ink supplying parts  14  and a stirrer  16 . The water bath  12  is filled with water  18 . As shown in  FIG. 4 , a hand mold  20  is ready above the water bath  12 .  
         [0039]     The ink supplying parts  14  are positioned above the water bath  12 . In the example shown in  FIG. 3 , the ink supplying parts  14  are positioned in the vicinity of the corner of the water bath  12 . The ink supplying part  14  comprises a base stand  22 , an arm  24  extending from this base stand  22 , and a tube  26  disposed and fixed on this arm  24 . According to the example shown in  FIG. 3 , two tubes  26  are disposed on one arm  24 . Only one tube  26  may be disposed on one arm  24 , while three or more tubes  26  may be also disposed.  
         [0040]     An ink  28  is supplied from the tube  26  toward the water bath  12 . This ink  28  is not hydrophilic. Typically, an oil-based ink may be used. This ink  28  has a property to float on the water  18 . By supplying the ink  28 , a thin ink layer  30  is formed on the surface of the water  18 . Preferred ink  28  is a rubber ink. The rubber ink includes fine rubber powder containing a pigment, with the rubber powder being dispersed in a solvent. The rubber ink is excellent in cohesiveness with the base layer  4  and the coat layer  8 . An ink  28  having a different color from that of the ink  28  supplied from one tube  26  may be supplied from another tube  26 .  
         [0041]     The ink supplying parts  14  can be retracted from the water bath  12  by rotation. What is indicated by a chain double-dashed line in  FIG. 3  is the arm  24  and the tube  26  which are in the state of retraction. In  FIG. 3 , position of the retraction of only one ink supplying part  14  is shown, however, all ink supplying parts  14  can be retracted. When the ink  28  is supplied, the ink supplying parts  14  are in the position shown by the solid line. Following completion of supplying the ink  28 , the ink supplying parts  14  are retracted. By the retraction, the area above the water bath  12  is opened.  
         [0042]     The stirrer  16  is positioned approximately at the center of the bottom of the water bath  12 . The stirrer  16  has four blades  32 . The stirrer  16  rotates around the axis  34 . According to this rotation, stirring of the water  18  is executed. This stirring also causes stirring of the ink layer  30 . Because the rotation velocity of the stirrer  16  is so slow, the ink  28  and the water  18  are hardly mixed together. The stirring results in formation of the ink layer  30  having a spiral pattern. In other words, the ink  28  is dispersed in an nonuniform manner on the surface of the water  18 . When two or more inks  28  having a different color with each other are used, a spiral pattern is formed with these colors being present admixed.  
         [0043]      FIG. 5  is a flow chart illustrating one example of a method of manufacturing the glove  2  shown in  FIG. 1 . In this method of manufacturing, the hand mold  20  is first preheated (STEP  1 ). The preheating elevates the temperature of the hand mold  20 . The temperature of the hand mold  20  may be from 50. degree. C. to 80. degree. C. Next, the hand mold  20  is dipped into a coagulant (STEP  2 ). Typical coagulant is an aqueous calcium nitrate solution. The dipping time period may be from 30 seconds to 60 seconds. To the surface of the hand mold  20  picked up from the coagulant is adhered the coagulant. Next, this coagulant is dried (STEP  3 ). The drying is conducted under a circumstance of from 40. degree. C. to 70. degree. C.  
         [0044]     Next, the hand mold  20  is dipped into a transparent rubber latex composition (STEP  4 ). The dipping time period may be from 15 seconds to 30 seconds. In this rubber latex composition are blended a crosslinking agent, a vulcanization accelerator, a crosslinking activator, a surfactant and various kinds of additives in addition to the base rubber. The term “transparent latex composition” means a latex composition that exhibits transparency upon crosslinking or hardening. The transparent latex composition is not required to be transparent in the stage of being a latex. In place of the rubber latex composition, a resin emulsion composition may be also used. In the present invention, exemplary latex composition involves rubber latex compositions and resin emulsion compositions.  
         [0045]     To the surface of the hand mold  20  picked up from the rubber latex composition is adhered the rubber latex composition. Next, this rubber latex composition is dried (STEP  5 ). The drying is conducted under a circumstance of from 40. degree. C. to 70. degree. C. The drying results in formation of the coat layer  8  comprising a crude rubber on the surface of the hand mold  20 .  
         [0046]     Next, the hand mold  20  is dipped into the water  18  filled in the water bath  12  shown in  FIG. 3  and  FIG. 4  (STEP  6 ). As described above, a spiral-patterned ink layer  30  is formed on the surface of the water  18  through ununiform dispersion of the ink  28 . As the hand mold  20  sinks, the ink layer  30  is gradually transferred to the surface of the coat layer  8 . Because the ink  28  is lipophilic, the ink  18  is not detached from the coat layer  8  even though the hand mold  20  is picked up from the water. Accordingly, the decorative layer  6  comprising the ink  18  is formed. Next, the decorative layer  6  is dried (STEP  7 ). While drying, the solvent included in the ink  28  is evaporated. While drying, the water  18  adhered to the coat layer  8  and the decorative layer  6  is also evaporated. A pattern is formed with this decorative layer  6 . The pattern may vary depending on the number of colors and amount of the ink  18  supplied to the water bath  12 , timing of supplying the ink  18 , time period and rotation velocity of stirring, shape and size of the blade  32 , and the like.  
         [0047]     Next, the hand mold  20  is dipped into another rubber latex composition (STEP  8 ). The dipping time period is from 30 seconds to 60 seconds. This rubber latex composition may be either transparent or nontransparent. In this rubber latex composition are blended a crosslinking agent, a vulcanization accelerator, a crosslinking activator, a surfactant, a colorant and various types of additives in addition to the base rubber. In place of the rubber latex composition, a resin emulsion composition may be also used.  
         [0048]     When the hand mold  20  is picked up from the rubber latex composition, the rubber latex composition is adhered to the surface of the decorative layer  6 . Next, this rubber latex composition is dried (STEP  9 ). The drying is conducted under a circumstance of from 50. degree. C. to 80. degree. C. The drying results in formation of the base layer  4  comprising a crude rubber on the surface of the hand mold  20 .  
         [0049]     Next, on the surface of the base layer  4  is coated a surface treatment agent (STEP  10 ). Examples of typical surface treatment agent include modified urethane and acryl-modified butadiene rubber. By coating the surface treatment agent, activity of the surface of the base layer  4  is elevated. By elevating the activity, wearing and taking off of the glove  2  can be readily conducted.  
         [0050]     Next, the hand mold  20  is allowed to stand under a circumstance of 90. degree. C. or greater and 150. degree. C. or less. Thus, a crosslinking reaction of the rubber is caused (STEP  11 ). According to the crosslinking, physical properties are imparted to the coat layer  8  and the base layer  4 . The decorative layer  6  cohesively contacts with the coat layer  8  and the base layer  4 . Accordingly, the glove  2  is obtained.  
         [0051]     Next, the glove  2  is removed from the hand mold  20 . This step is referred to as mold removal (STEP  12 ). Concurrently with the mold removal, the glove  2  is turned inside out. By turning it inside out, the coat layer  8  appears on the obverse face. Because the coat layer  8  is transparent as described above, the decorative layer  6  is visible through the coat layer  8 . Thereafter, the gloves  2  are shipped following steps of drying, treatment with chlorine, cutting, marking and the like as needed.  
         [0052]     This glove  2  has a marble pattern formed with the decorative layer  6 . This glove  2  is excellent in designing performances. This glove  2  has an apparently distinct appearance from that of conventional gloves exhibiting single color. According to this method of manufacture, gloves  2  which achieve wide color variations can be obtained. In addition, the pattern of this glove  2  is yielded incidentally, therefore, patterns of two gloves  2  can not be identical. By way of such gloves  2 , separate use for each application can be readily carried out.  
         [0053]     The gloves according to the present invention are suited for household affairs at general home. The gloves are also suited for occupations at restaurants. In addition, the gloves are also suited for outdoor operations.  
         [0054]     The foregoing description is merely an illustrative example, and various modifications may be made without departing from the principle of the present invention.