Process for Flexibly Manufacturing Wetsuit or Garment by Integrally Forming a Functional Surface Layer on a Rubber Foam Subtrate

Abstract

A process for flexibly making a wetsuit or the like is disclosed by integrally forming a functional surface layer on a rubber foam substrate sheet, thereby rendering the function of the surface layer for the wetsuit or the like.

Claims

1. A process for flexibly manufacturing a wetsuit or the like comprising: Preparing a functional surface layer; Preparing a rubber foam substrate sheet; and Integrally forming said functional surface layer to said rubber foam substrate sheet to obtain a composite sheet, which is subjected for vulcanization foaming to produce a rubber foam composite product; and further processed to be a wetsuit or the like.

2. A process according to claim 1, wherein said functional surface layer is pre-formed as a functional surface-layer sheet member as extruded through a plurality of rollers.

3. A process according to claim 2, wherein said functional surface-layer sheet member is made of a functional surface layer material.

4. A process according to claim 3, wherein said functional surface layer material comprises at least a functional ingredient added into a formula for making the functional surface layer.

5. A process according to claim 4, wherein said formula for making said functional surface layer comprises: a synthetic rubber selected from: CR, EPDM and CSM; calcium carbonate; mica powder; zinc oxide; magnesium oxide; foaming agent; promoter; and at least one said functional ingredient.

6. A process according to claim 4, wherein said functional ingredient is an anti-UV organic or inorganic color pigment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 shows a prior art for making an extruded green rubber foam sheet.

[0012] FIG. 2 is a process flow chart showing the production in accordance with the present invention.

DETAILED DESCRIPTION

[0013] As shown in FIG. 2, a green rubber foam compound blended with carbon black in a two-roll mill 1 is fed into a rubber foam sheet extruder 2 through a hopper 21 to produce a rubber foam substrate sheet S as extruded from a die 22 of the extruder 2. At least a green rubber foam stock dispenser 3 is filled with at least a functional surface layer material therein. A two-roll feeding roller set 4 and four-roll calender 5 are mounted above the rubber foam sheet S from the rubber foam sheet extruder 2. The functional surface layer material may include pigment, ultraviolet absorbers (or anti-UV agent), or any other functional additives or agents as blended with synthetic rubber, such as: Chloroprene Rubber (CR), Ethylene Propylene Diene Monomer rubber (EPDM), and Chlorosulfonated Polyethylene rubber (CSM). The formula will be described in detail hereinafter. The functional surface layer material as filled into foam stock dispenser 3 will be downwardly loaded through the 2-roll feeding roller set 4 to deliver a functional surface-layer sheet into the four-roll calender 5 with pre-set gauge (0.3-3 mm, but not limited) of the functional surface-layer sheet F.

[0014] The additives, agents and functional ingredients of the functional surface layer material comprises: a pigment, an ultraviolet absorber, an ozone resistant additive, a foaming agent, a promoter, mineral fillers, and other ingredients, or their mixtures. The pigment may be referred as a functional ingredient. Naturally, carbon black may serve as a black pigment.

[0015] For example, if it is intended to flexibly make versatile colored rubber foam products, the rollers of calender as shown in FIG. 2 may be respectively fed with different colored rubber compound.

[0016] This is very helpful for a flexible manufacturing of the factory production. For example, customer A, who prefers color A, there only green rubber foam stock dispenser 3 for color A is subjected to the production line. Since each functional surface layer sheet F only requires smaller quantity of material in comparison with the thicker substrate sheet S, which requires much more material. Therefore, it is very flexible and economic for the production management. Otherwise, if for making color A product by using the system as shown in FIG. 1, the raw material R for color A must be fed into the extruder E. When it is intended to change as color B product, a whole set of raw material must then be replaced with color B raw material. If the customer order is merely a small order, it may cause difficulties for the production, management and material control.

[0017] So, this invention discloses a flexible and economic manufacturing process, just by modifying, adjusting, manipulating, and controlling the functional surface layer F, without changing the whole set of the foam rubber product including the substrate sheet S.

[0018] The functional surface-layer sheet F after calendering is then laminated through pressing roller set 6 as shown in FIG. 2, Furthermore, the thickness of the surface-layer sheet F may be further tuned by adjusting each nip between two adjacent rollers of the calender 5.

[0019] Then, the sheet F is driven by the pressing roller set 6 which includes a pair of pressing rollers 61, 62 having the sheet F forwardly driven between the pressing rollers 61, 62. In this step, the pressing roller set 6 may apply pressure and heat in order for thermally bonding the functional surface-layer sheet F with the substrate sheet S which is also driven forwardly by the pressing roller set 6.

[0020] Due to pressure and heat applied to the surface-layer sheet F and the substrate sheet S, the surface-layer sheet F and the substrate sheet S are then firmly bonded together to be a composite sheet stock 7.

[0021] The composite sheet stock 7 is then performed for vulcanization & foaming to produce a rubber foam composite product, which may be continuously fabricated as a wetsuit or the like. For example, a wetsuit or garments for water sports including diving, surfing, triathlon, fishing, river tracing and other water sports.

[0022] The functional surface layer material may contain with or without foaming agent. The ingredients or formula of the functional surface layer material are respectively shown in the following tables:

TABLE-US-00001 TABLE 1 Rubber Foam having foaming functional surface layer Ingredients Weight % Synthetic Rubbers (CR, EPDM, CSM) 45~55 Calcium carbonate 5~30 Mica powder 5~30 Zinc oxide 1~5 Magnesium oxide 1~4 Foaming agent 1~8 Promoter 0.2~0.8 Organic/inorganic pigment, UV absorbers 0.1~25

TABLE-US-00002 TABLE 2 Rubber Foam without foaming on surface layer Ingredients Weight % Synthetic Rubber (CR, EPDM, CSM) 45~55 Calcium carbonate 5~30 Mica powder 5~30 Zinc oxide 1~5 Magnesium oxide 1~4 Promoter 0.2~0.8 Organic/inorganic pigment, UV absorbers 0.1~25 Note: Carbon black may be added therein. The UV absorber may also refer to anti-UV agent.
The finished product of Tables 1 and 2 are respectively tested as follows:

TABLE-US-00003 TABLE 3 Test data of Table 1 Formula This This This invention invention invention Rubber having surface having surface having surface Foam layer of layer layer Test items (Prior Art) 0.5 mm T I.P. % 1 mm T I.P. % 1.5 mm T I.P. % Tear strength 2.5 2.7 7.4 3.32 24.6 3.74 33.1 ASTM D624-C, Kg/cm.sup.2 Tensile strength ASTM 5.5 8.5 35.3 10.11 45.5 12.74 56.8 D412-A, Kg/cm.sup.2 Note: I.P. % is Increased Percent, %. T is thickness.

TABLE-US-00004 TABLE 4 Test data of Table 2 Formula This This This invention invention invention Foam having surface having surface having surface Rubber layer of layer layer Test items (Prior Art) 0.5 mm T I.P. % 1 mm T I.P. % 1.5 mm T I.P. % Tear strength 2.5 3.0 16.6 3.4 26.4 4.1 39 ASTM D624-C, Kg/cm.sup.2 Tensile strength ASTM 5.5 9.02 39 10.48 47.5 13.14 58.1 D412-A, Kg/cm.sup.2 Note: I.P. % is Increased Percent, %. T is thickness.

[0023] The product of the present invention is also subjected for anti-ozone test according to ASTM 1149 as below mentioned:

[0024] The rubber foam specimen is tested in a chamber having ozone concentration of 100 pphm at 40 C. and the specimen is elongated for 30% and tested for 72 hours duration. The tested specimen shows no deformation or corrosion even attacked by ozone, proving this invention to be ozone resistant.

[0025] The present invention has the following advantages: [0026] 1. It may help a flexible manufacturing for the factory production since a versatility of functional surface layers may be optionally chosen. Each functional surface layer may be added therein with a small amount of functional ingredient, such as color pigment. This is especially helpful for customer-oriented manufacturing. [0027] 2. It is more economic for production management and inventory control for saving cost and for preventing waste of materials. [0028] 3. It is environmentally friendly since waste material may be minimized. [0029] 4. Since the surface layer is so thin (0.3 mm-3 mm), it is easily processed, and the molding or printing pattern or surface design can be easily achieved, directly on the surface layer. Once the surface treatment or decoration is finished, the surface layer is then integrally formed with the substrate sheet of rubber foam. It is easily manipulated or operated (before integrally formed with the substrate sheet), just processing the surface layer, rather than the entire rubber foam product with larger thickness.

[0030] The functional surface layer may be incorporated therein with any other suitable ingredients for rendering the expected functions.

[0031] The present invention may be further modified without departing from the spirit and scope of this invention.