Preparation and Bonding Properties of Fabric Veneer Plywood

Abstract

Fabric veneer panels were prepared using ethylene-vinyl acetate copolymer film (EVA) as the intermediate layer and poplar plywood as the substrate. Eight fabrics with different compositions were selected for evaluation to screen out fabric materials suitable for poplar plywood veneer. The fabrics were objectively analyzed by bending and draping, compression, and surface roughness, and subjectively evaluated by establishing seven levels of semantic differences. ESEM, surface adhesive properties, and peel resistance tests were used to characterize the microstructure and physical–mechanical properties of the composites. The results show that cotton and linen fabrics and corduroy fabrics are superior to other fabrics in performance, and they are suitable for decorative materials. Because the fibers of the doupioni silk fabric are too thin, and the fibers of felt fabric are randomly staggered, they are not suitable for the surface decoration materials of man-made panels. The acetate veneer surface gluing performance was 1.31 MPa, and the longitudinal peel resistance was 20.98 N, significantly exceeding that of other fabric veneers. Through the subjective and objective analysis of fabrics and gluing performance tests, it was concluded that, compared with fabrics made of natural fibers, man-made fiber fabrics are more suitable for use as surface finishing materials for wood-based panels. The results of this study provide a theoretical basis and process reference for the development of environmentally friendly decorative panels, which can be expanded and applied to furniture, interior decoration, and other fields.

1. Introduction

Driven by new consumption concepts, consumers’ standards for home space design are continuously upgrading, and whole-house customized furniture has become a new consumption growth point in China’s home furnishing industry [1,2]. Fabrics, with their dual advantages of functional attributes and aesthetic value, have become a core material choice in contemporary interior design [3,4,5]. In the home environment, fabrics are mostly used as carpet, wallboard, seat covers, and other furniture covering products, mainly to achieve user-led personalized expression, but this is not conducive to the standardized production of customized furniture [6,7].

The application of flat-pressing technology to attach fabrics to the surface of artificial board substrates is conducive to the mechanized production of customized furniture [8,9,10]. However, due to the complex orientation of fabric fibers, the penetration path of adhesives during the gluing process with the substrate is complicated, making it extremely prone to problems such as adhesive penetration and uneven gluing. Bai Yumei [11] used cotton fabric as the facing material and solid wood panels as base material, and used soybean-based adhesive to bond the fabric and panels together through hot pressing. The obtained solid wood panels with cotton-fabric facing showed certain adhesive marks and numerous adhesive spots on the surface. To address this issue, kaolin was used as an inorganic filler for the soybean-based adhesive to block the loose pores of the fabric, eliminating the problem of adhesive penetration on the veneer surface. Nevertheless, there are still some problems as the preparation process of the adhesive and facing panel is relatively complicated.

Thermoplastic resin adhesives can be used as the material of the intermediate layer to solve bonding challenges between different materials because of their formaldehyde-free characteristics and more uniform gluing [12,13,14]. Low-cost thermoplastic resin adhesives such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), and ethylene-vinyl acetate (EVA) are widely used [15,16,17,18]. During hot pressing, molten resin penetrates the gaps between fabric fibers, forming mechanical anchoring after cooling and generating intermolecular forces with the fiber surface to achieve high-strength bonding and reduce dependence on additional glue [19,20]. Lv et al. [21] used high-density polyethylene (HDPE) on the surface of wood–plastic substrate as an intermediate layer. Wood fiber/high-density polyethylene (WF/HDPE) wood–plastic boards were used as the base material, and canvas, nylon fabric, and polyester fiber fabric were pasted on the surface. They found that the color of canvas and nylon fabrics changed significantly, while the color of polyester fabrics did not change significantly. The tensile and bending properties of the plywood decreased significantly, and the impact toughness was greatly improved. Zhou Xuelian et al. [22] selected cotton and linen fabric as decorative materials, HDPE powder as an intermediate bonding material, and WF/HDPE wood–plastic boards as substrate. Wood–plastic composites were prepared by the hot-pressing process. The results showed that the surface bonding strength of the WF/HDPE composite substrate reached 3.64 MPa, but the color and brightness of the fabric changed significantly after hot pressing, becoming brighter and less red, and local HDPE overflow appeared on the surface of the fabric veneer panels.

Compared with other thermoplastic resin adhesives, EVA has a lower melting temperature (around 85 °C), reducing fabric color changes caused by high temperatures during the lamination process. Hu Manyu et al. [23] used EVA as an intermediate layer to prepare composite fabrics, where the EVA was tightly bonded with the yarns and fibers of the two fabric layers, and the adhesive layer formed gaps and micro-holes, with a peeling strength of 32.55 N. Zhang Xinhao et al. [24] used EVA film as a flexible reinforcement and adhesive material of Fraxinus mandshurica veneer to prepare EVA film-reinforced Fraxinus mandshurica decorative veneer, and the surface bonding strength of the Fraxinus mandshurica veneer MDF reached 1.17 MPa. Zou et al. [25] selected EVA film as the intermediate layer and polyurethane (PU) leather as the finishing material to prepare leather-finished plywood, finding that the optimal surface bonding strength was 1.89 MPa when using plywood as the base material to prepare PU leather decorative panels.

Based on this, the author proposed to analyze the applicability of eight types of fabrics as facing materials for fabric-faced panels by combining subjective tactile perception with objective mechanical testing. Meanwhile, the fabric, EVA, and substrate were to be bonded together by one-time hot pressing with ethylene-vinyl acetate copolymer (EVA) film as an intermediate layer. The gluing performance of the fabric-faced panel was evaluated by tests such as surface gluing strength and peel resistance, while the bonding force among the fabric, EVA, and substrate was analyzed.

2. Materials and Methods

2.1. Materials

Poplar plywood (Shanghai Xinban Wood Industry Co., Ltd., Shanghai, China) measuring 200 mm × 200 mm × 15 mm in size, 0.56 g/cm³ in density, and 8%–10% in moisture content. EVA film (Fujian Furong New Materials Co., Ltd., Fujian, China) with a thickness of 0.1 mm and a density of 0.91 g/cm³ was used as the intermediate layer, and one layer was used to bond different materials at a time.

Due to significant differences in the inherent properties of different fabrics, to explore the differences in veneer panels prepared from various fabric types, finishing materials were selected based on fabric fiber types. Eight fabrics with different compositions and structures were chosen as experimental subjects, and their structural parameters are shown in

Table 1. Fabric specification parameters.

Name	Composition	Thickness (mm)	Mass per Square Meter (g/m2)	Source
Polyester fiber	95% polyester, 5% spandex	0.62	340	Buermei Textiles Business Department, Hubei, China
Double-sided acetate satin	97% polyester, 3% spandex	0.38	310	Buermei Textiles Business Department, Hubei, China
Cotton fabric	100% cotton	0.40	370	Gufeng Garment Accessories Firm, Hebei, China
Cotton–linen	40% linen, 60% cotton	1.29	460	Gufeng Garment Accessories Firm, Hebei, China
Pure-color linen	100% linen	0.86	185	Yumai Textile Co., Ltd., Zhejiang, China
Corduroy	Nylon and polyester	1.09	350	Yumai Textile Co., Ltd., Zhejiang, China
Doupioni silk	100% mulberry silk	0.19	100	Fengzi Silk Co., Ltd., Zhejiang, China
Felt	Cotton felt, acrylic cotton, space cotton, etc.	0.90	195	Gufeng Garment Accessories Firm, Hebei, China

.

2.2. Preparation of Veneered Plywood

Using fabric as the decorative layer and plywood as the substrate, EVA served as the intermediate layer to bond the decorative layer and the substrate. A series process of hot pressing and cold pressing was adopted, with the hot-pressing temperature, pressure, and time controlled at 110 °C, 1.0 MPa, and 100 s, respectively. After hot pressing, cold pressing at room temperature was performed for shaping, with the cold pressing pressure being 1.0 MPa with a duration of 5 min, as shown in Figure 1.

2.3. Performance Testing and Characterization

2.3.1. Characterization of Fabric Properties

An integrated approach combining objective quantification and subjective evaluation was employed to characterize how the physical properties of fabrics influenced tactile sensation and visual appearance. Surface roughness assesses microscopic geometry and tactile smoothness of fabric surface; compression properties evaluate loftiness, fullness, and resilience through thickness variation and recovery capacity; while bending and draping properties jointly measure a fabric’s resistance to deformation and its ability to form gentle curves under its weight, reflecting softness, stiffness, and natural draping behavior. To correlate instrument-measured data with human sensory perception, the semantic differential method was implemented, where evaluators rated fabrics across tactile dimensions using structured rating scales, thereby comprehensively quantifying the holistic stylistic properties of textiles.

• Roughness Performance. Based on the standard FZ/T 01115-2012 [26] “Test Method for Fabric Surface Roughness Performance” preparation specifications for 100 mm × 100 mm fabric specimens. Surface roughness was evaluated by the arithmetic mean deviation of the profile (Ra). Six specimens were tested at each experimental level, and the results were averaged.
• Compression Performance. Based on the standard GB/T 24442.2-2009 [27] “Determination of Compression Performance of Textiles”. First, the fabric specimen with a specification of 35 mm × 35 mm was prepared. Second, the fabric specimen was spread on the specimen table of the mechanical testing machine and loaded. During the test, the load was increased from 0 N to 1000 N. The changes in the thickness of the loaded specimen were recorded every 0.1 s. The maximum displacement was recorded when the load was 1000 N. Six specimens were selected for testing under each respective test level, and the results were averaged.
• Bending and Drapeability. Specimens were cut into 240 mm × 25 mm rectangles, and the 1/4 and 3/4 positions in the length direction were stitched and fixed. The treated specimens were fixed at the stitching points and vertically hung on a white KT board on the wall. After the specimens stabilized, photos were taken with a camera at the same horizontal level and directly facing the specimens, with all shooting parameters fixed. The photos were then imported into image processing software to extract characteristic parameters using its function to measure distances or lengths. The width and height of the water drop shape formed by the fabric, as well as the horizontal and vertical distances of the side wings sagging, were introduced as evaluation indicators. Three specimens were tested in both warp and weft directions, and the results were averaged [28].
• Semantic Differential Method. A seven-point rating scale was used, and five groups of contrasting perceptual vocabulary were designed for tactile evaluation, as shown in

  Table 2. Tactile evaluation elements.

  Tactile Terms Evaluation Values 1–7	Meaning
  Soft-hard	Difficulty of fabric deformation
  Smooth-rough	Surface friction sensation
  Light-heavy	Perceived weight per unit area
  Elastic-stiff	Recovery ability after compression
  Fluffy-tight	Fiber porosity and airiness
  Smooth-sticky	Resistance during sliding

  . In order to compare the tactile differences, eight samples with the same evaluation factor were scored first, and then the six tactile evaluation factors were scored in turn. Fifteen subjects aged 18–60 were invited to test the fabrics; they could touch for 5–10 s at a time and dictate the scores of each evaluation factor, which were recorded by the experimenters.

2.3.2. Characterization of Veneered Plywood

• Surface Bonding Strength. Based on the standard GB/T 17657–2022 [29], specimens of fabric veneer plywood with specifications of 50 mm × 50 mm were prepared. They were tested with a mechanical testing machine to determine the maximum damage load. Six specimens were selected for testing under each test level, and the results were averaged.
• Peel Resistance. Based on the standard GB/T 17657–2022 [29] “Test Methods of Evaluating the Properties of Wood-Based Panels and Surface Decorated Wood-Based Panels”, preparation specifications for 25 mm × 100 mm fabric veneer plywood specimens. They were tested with a mechanical testing machine to determine the maximum damage load. Six specimens were selected for testing under each test level, and the results were averaged.

2.3.3. Microscopic Morphology of the Gluing Interface

The fabric veneer plywood specimens were cut to a size of 5 mm × 3 mm. After gold spraying of the cross-section, the gluing interface between the decorative fabric, the EVA film interlayer, and the plywood substrate was analyzed via environmental scanning electron microscopy (ESEM).

3. Results

3.1. Analysis of Different Fabric Properties

Objective evaluation was used to quantitatively analyze the physical properties of materials, and the visual aesthetics, fullness, and surface roughness of raw fabrics were analyzed through fabric compressibility and roughness to reflect tactile and aesthetic styles. Sensory evaluation of different fabrics was conducted through direct contact, relying on the human sensory system to perceive and judge various characteristic attributes of the materials. The correlation between subjective and objective evaluations was established to jointly analyze the inherent properties of different fabrics.

3.1.1. Compression Performance

The deformation capacity of materials under low compression loads can partially simulate the tactile sensations obtained by evaluators when touching or pressing the material surface. Generally, a larger deformation indicates better fullness and softness. As shown in Figure 2a, polyester and acetate, two fabrics made of chemical fibers, had relatively low compression deformation and compression deformation rates. Corduroy, a blended fabric with a hairy surface, had the largest compression deformation, but this also resulted in a lower compression deformation rate than felt.

The tangential slope directly reflects the deformation degree of different materials under compressive loads; The bigger the slope, the better softness and fullness. As shown in Figure 2b, with increasing compression load, the fiber structure in the fabric gradually became denser, and the rate of deformation increase slowed down. Cotton–linen, felt, and corduroy had relatively larger slopes among all fabrics, indicating better fullness. Doupioni silk fabric had the lowest slope and relatively poor fullness.

3.1.2. Roughness Performance

Surface roughness of fabric is an important tactile index. Excessive roughness may cause skin friction discomfort, while too low roughness may feel slippery. Tactile roughness also influences users’ judgments of product quality, and moderate roughness may convey visual associations of “naturalness” and “durability,” whereas excessive smoothness may appear cheap. Additionally, the way light reflects off the fabric is affected by roughness. Rough surfaces scatter light, presenting a matte texture; smooth surfaces reflect light more concentratedly, producing a glossy effect. For customized furniture, the fabric’s surface texture is very important, and different surface roughness levels may affect the overall home decoration style, while different fabric fiber compositions determine the differences in surface roughness. As shown in Figure 3b, the contour line of doupioni silk changed tightly, indicating finer fabric fibers, but its surface roughness value Ra was relatively low, meaning its surface was relatively smooth. Cotton–linen and linen fabrics had relatively high surface roughness values (as shown in Figure 3a) because linen fibers have longitudinal grooves and natural transverse nodes on their surfaces, which directly lead to a rough tactile sensation. The crystallinity of cellulose in linen fibers is much higher than that in cotton, with more tightly arranged molecular chains, resulting in high fiber rigidity, poor flexibility, and a stiff, rough touch. Moreover, flax fibers contain a small amount of lignin and pectin, which makes them brittle and hard. The residual colloid on the surface of flax fibers with incomplete degumming further increases roughness. The irregular fluctuations in the contour map confirm the characteristics of linen fibers. Corduroy fabric has a grooved surface structure (Figure 3b), with its contour line corresponding to the alternating arrangement of ribbed strips and grooves. The wavelength period is matched with the spacing of ribbed belts, and the tiny protrusions formed by fiber ends show high-frequency and small-amplitude fluctuations on the contour line. The fibers of felt fabric are randomly interwoven, and their contour lines, likewise, exhibit an irregular and random pattern.

3.1.3. Bending and Drapeability

Good bending performance allows fabrics to conform to the curved surfaces or edges of plywood, avoiding wrinkles or cracks; excellent drapeability ensures that fabrics naturally hang on vertical or inclined surfaces, forming smooth and uniform visual effects. Excessively high bending stiffness or low drapeability in fabrics may result in uneven veneers, edge warping, or poor detail processing, affecting the aesthetics and practicality of veneer panels.

As a direct reflection of fabric aesthetics, the bending and drapeability of the tested fabrics are shown in Figure 4. The drape coefficient, a core indicator for measuring fabric drapeability, reflects the degree of sagging under self-weight. A smaller drape coefficient indicates more natural and smooth sagging and better drapeability, making the fabric more suitable as a finishing material for irregular furniture. As shown in Figure 4a, the warp-direction drape coefficients of all fabrics were slightly higher than those in the weft direction. The differences between warp and weft directions in polyester, cotton–linen, and corduroy were not significant, while doupioni silk had the largest warp-direction drape coefficient (0.78), and acetate had the smallest (0.24), indicating that acetate had the best drapeability among the eight fabrics. Felt, made by processing and bonding cotton felt, acrylic cotton, space cotton, etc., has elasticity but almost no drapeability.

Bending stiffness refers to the ability of a fabric to resist bending deformation under external forces, which reflects the softness or stiffness of fabric. Higher bending stiffness means the fabric is less prone to bending, appearing stiff and structured; conversely, lower bending stiffness indicates softness and easy deformation, suitable for ensuring higher flatness and bending resistance of veneer panels during large-format standardized production of artificial boards. As shown in Figure 4b, when tested only in the warp direction, corduroy had the lowest bending stiffness (12.42), while doupioni silk had the highest (72.79). However, corduroy’s drape coefficient was not lower than acetate’s because corduroy has an obvious texture and a hairy surface, resulting in low bending stiffness but not an extremely low drape coefficient. Acetate fabric had a lower weft-direction bending stiffness (6.92), and combined with its thinner thickness, it can be concluded that it is a relatively soft fabric.

3.1.4. Subjective Evaluation

A total of eight fabrics were tested, each involving six groups of sensory vocabulary, resulting in an 8 × 6 sensory evaluation matrix for fabric tactile perception. The test results were statistically analyzed, and the sensory vocabulary scores corresponding to the six furniture styles were calculated as evaluation values (

Table 3. The score of the emotional vocabulary corresponding to the six kinds of fabric touch evaluation.

Sensory Vocabulary	Polyester	Acetate	Cotton	Cotton-Linen	Linen	Corduroy	Doupioni Silk	Felt
Soft-hard	2.23	1.23	3.31	4.77	4.85	3.08	4.08	5.69
Smooth-rough	1.92	1.31	3.38	5.69	5.54	4.85	2.62	5.62
Light-heavy	1.85	1.46	2.15	4.85	4.69	4.38	2.62	6.62
Elastic-stiff	1.85	2.92	4.77	4.77	5.46	4.46	5.62	7.00
Fluffy-tight	5.38	5.85	5.54	3.62	4.31	3.46	6.77	2.92
Smooth-sticky	2.23	1.23	3.85	5.31	5.38	4.77	2.54	5.92

). Radar maps of haptic evaluations of different fabrics are shown in Figure 5. It can be seen that most people perceived polyester, acetate, cotton fabric, and doupioni silk as soft, smooth, lightweight, but relatively tight. Cotton–linen, linen, and corduroy were more moderate in all aspects, but fluffier. Felt, although fluffy, was perceived as hard, rough, and sticky. Cotton–linen had the lowest score in the “fluffy–tight” sensory word group, indicating it was the fluffiest among the eight fabrics. Similarly, cotton–linen and linen had higher scores in the “smooth–rough” group, suggesting rougher surfaces, which aligned with the objective test results above.

3.2. Analysis of Veneer Performance for Different Fabric Types

To investigate the influence of different fabric types on veneer performance, a one-step hot-pressing process was used to apply various fabrics to plywood surfaces. Their bonding strength and peel resistance were analyzed, while microscopic observation of the bonding interface visually reflected the adhesion among the fabric, EVA, and poplar plywood.

3.2.1. Surface Bonding Strength

The surface bonding strength of poplar plywood veneered with different fabrics via one-step hot pressing is shown in Figure 6a,b, with failure surfaces depicted in Figure 6c. Results showed that seven fabrics achieved bonding strengths above 0.4 MPa, by the standard GB/T 15104–2021 [30], indicating their suitability for veneering artificial boards. Due to the thinness of doupioni silk, part of the EVA penetrated through to the fabric surface during hot pressing (Figure 6d), making it impossible to test its surface bonding strength. Comparatively, acetate exhibited the highest bonding strength (1.31 MPa), likely due to its thin thickness and low mass, allowing uniform EVA penetration into both the fabric and plywood. Cotton fabric, despite a similar thickness to acetate, had partial EVA melting through fiber intersections (Figure 6e), because the fiber arrangement density of cotton cloth is lower than that of acetate cloth. Felt fibers are randomly staggered, with no distinction between warp and weft, and usually have a high density. When pressed, molten EVA completely randomly entered the felt with large and irregular pores, resulting in the phenomenon of no EVA in poplar fibers, which made the bonding strength of felt veneer lower than that of other fabric veneers by only 0.51 MPa (Figure 6f). In addition, the results are also related to the experimental results of fabric roughness, which further reflects the penetration direction of the EVA adhesive layer under melting. Fabrics with high surface roughness, such as linen and cotton and linen fabrics, have thicker fibers, and EVA covers each coarse fiber more completely, while fabrics with smaller fibers will have more uniform and in-depth EVA in the infiltration process. Therefore, when selecting fabrics for veneering, both composition and thickness must be considered: thickness should not be lower than 0.35 mm to ensure a suitable fiber structure.

3.2.2. Peel Resistance

Peel resistance tests for poplar plywood veneered with different fabrics are shown in Figure 7a,b, with failure surfaces in Figure 7c. For acetate fabric, peeling direction significantly affected results: peel force reached 20.98 N along the grain (parallel direction), far exceeding other fabrics. As shown in Figure 7d, EVA penetrated both the fabric and poplar during hot pressing, wrapping fabric fibers and forming a “nail-glue” structure with poplar veneers, creating a cohesive composite. Cross-grain (transverse) peeling force was only 5.64 N. Wood morphology analysis indicates that the parallel “peak-valley” structure along the grain facilitates EVA flow and diffusion, enhancing interfacial adsorption and mechanical interlocking. Exposed cross-sectional surfaces with higher roughness and honeycomb-like pores allow EVA to penetrate deeply, forming a “pinning effect” that strengthens mechanical interlocking, explaining why cross-grain peel resistance was higher than parallel-grain for cotton–linen, linen, and corduroy. Corduroy’s grooved surface increased EVA contact area (Figure 7e), but its cross-grain peel resistance of 8.68 N (compared to parallel grain) indicated minimal impact from the groove structure on bonding.

4. Conclusions

• When selecting fabrics for surface veneering, good drapeability is suitable for irregular furniture, while excellent bendability helps avoid wrinkles or cracks during large-format standardized production. Fabrics with good compression performance and moderate surface roughness are preferred; fluffy fabrics are popular, but excessive roughness affects usability, and overly smooth surfaces compromise aesthetics.
• Although synthetic fiber fabrics seem to be more suitable for veneering, natural fiber fabrics are widely favored in the home environment. For example, although the surface of linen fabrics is rough and its elasticity is low, it provides a natural texture and simple attraction consistent with natural style spaces, catering to different aesthetic preferences.
• Synthetic fiber fabrics have better adhesive properties than natural fiber fabrics, but fabrics with a thickness less than 0.35 mm will have the risk of EVA infiltrating into the surface during hot pressing, resulting in a glue-like film, thus changing the original touch. Using EVA as the intermediate layer to combine fabric with poplar plywood greatly reduces formaldehyde emission and environmental pollution compared with traditional adhesives. However, the study of fabric veneer in the target environment, such as humidity and durability under ultraviolet irradiation, still needs further exploration.