## 1 Introduction  
The development of infrastructure and buildings in the last few decades has been very fast, and is directly proportional to the increasing need for paint as a coating. Paint is used as a coating to protect the building from an object and as an interior or exterior decoration. Paint can provide a high aesthetic value to the building, making it a livable building [1; 2; 3]. Paints as coatings can be classified into three main categories: architectural or construction coatings, product or equipment coatings, and coatings with special purposes, such as preventing corrosion. Of the three main categories, emulsion paint is included in the first category [2]. Emission paint is water-based paint that coats the internal and external surfaces of a building. The quality and performance of emulsion paints are highly dependent on their constituent components, such as binders, pigment solvents, and additives [2; 4]. The binder in paint plays an important role in attaching the pigment to the surface of the object being painted and becoming a continuous film. The type and amount of binder used in paint affects performance factors such as durability, stain resistance, adhesion,and crack resistance. In general, the higher the ratio of binder to pigment, the higher the paint quality [4, 6, 7]. Commonly used binders in emulsion paints are water-dispersed binders such as polyvinyl acetate (PVAc) and styrene acrylic, known in the paint industry as synthetic latex [2, 8]. PVAc-based binders are commercial adhesives that are widely used in emulsion paints. PVAc was chosen as the binder considering the nature of the PVAc material, which easily disperses in water, forms thin and colorless films, has good resistance to weathering and biodegradation, good initial adhesion, and low production costs [9, 10]. The use of PVAc in some cases causes allergic reactions due to the formaldehyde content contained in these products [8, 11, 12]. This has attracted several studies to develop binders for emulsion-based paints that are environmentally friendly, non-toxic, have high adhesive properties, and have low cost. One of the potential materials that can replace PVAc is a natural polymer-based binder. Natural polymer-based binders are believed to be a solution to replace synthetic latex, such as PVAc, as emulsion paint binders. Natural polymer-based binders have adhesive physical properties that are quite competitive with PVAc. There are significant differences between natural polymers and PVAc; the film formed by natural polymers is more elastic. Natural polymers have been widely applied to various types of paint, including gum arabic, turpentine, starch, protein, drying oil, beeswax, and natural latex [2, 13, 14]. One of the uses of natural polymers as raw material for emulsion paint binders is gum arabic, produced by Acacia Senegal. Gum arabic is generally used as a binder in watercolors because it is easily soluble in water. The use of gum arabic as a paint binder has the disadvantage of strong hydrocolloid properties, and makes the paint's drying time longer. Therefore, using gum arabic as a paint binder is more effective when mixed with PVAc. This is intended to improve the performance of gum arabic and reduce the use of PVAc as a paint binder with low cost [2, 15, 16]. In addition to gum arabic, natural rubber latex, better known as natural latex, produced by the Hevea brasiliensis plant, has the potential to be used as a binder or coating. This refers to the ability of natural latex to form a flexible film layer, which can coat a surface with a fairly good adhesive that is expected to reduce cracks in the emulsion paint [17]. The use of natural latex has challenges in its application. Natural latex has strong hydrocolloid properties, so it takes longer to dry [8, 18]. Dry time is very important in the paint industry because it is related to the paint's resistance to water, the ability of the paint to adhere to the media, and the ability of the paint to bind to the substrate [8, 14].